Sample records for aberrant motor behavior

  1. Aberrant Hyperconnectivity in the Motor System at Rest Is Linked to Motor Abnormalities in Schizophrenia Spectrum Disorders.

    PubMed

    Walther, Sebastian; Stegmayer, Katharina; Federspiel, Andrea; Bohlhalter, Stephan; Wiest, Roland; Viher, Petra V

    2017-09-01

    Motor abnormalities are frequently observed in schizophrenia and structural alterations of the motor system have been reported. The association of aberrant motor network function, however, has not been tested. We hypothesized that abnormal functional connectivity would be related to the degree of motor abnormalities in schizophrenia. In 90 subjects (46 patients) we obtained resting stated functional magnetic resonance imaging (fMRI) for 8 minutes 40 seconds at 3T. Participants further completed a motor battery on the scanning day. Regions of interest (ROI) were cortical motor areas, basal ganglia, thalamus and motor cerebellum. We computed ROI-to-ROI functional connectivity. Principal component analyses of motor behavioral data produced 4 factors (primary motor, catatonia and dyskinesia, coordination, and spontaneous motor activity). Motor factors were correlated with connectivity values. Schizophrenia was characterized by hyperconnectivity in 3 main areas: motor cortices to thalamus, motor cortices to cerebellum, and prefrontal cortex to the subthalamic nucleus. In patients, thalamocortical hyperconnectivity was linked to catatonia and dyskinesia, whereas aberrant connectivity between rostral anterior cingulate and caudate was linked to the primary motor factor. Likewise, connectivity between motor cortex and cerebellum correlated with spontaneous motor activity. Therefore, altered functional connectivity suggests a specific intrinsic and tonic neural abnormality in the motor system in schizophrenia. Furthermore, altered neural activity at rest was linked to motor abnormalities on the behavioral level. Thus, aberrant resting state connectivity may indicate a system out of balance, which produces characteristic behavioral alterations. © The Author 2017. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  2. Chronic Nicotine Mitigates Aberrant Inhibitory Motor Learning Induced by Motor Experience under Dopamine Deficiency

    PubMed Central

    Krok, Anne C.; Xu, Jian; Contractor, Anis; McGehee, Daniel S.; Zhuang, Xiaoxi

    2016-01-01

    Although dopamine receptor antagonism has long been associated with impairments in motor performance, more recent studies have shown that dopamine D2 receptor (D2R) antagonism, paired with a motor task, not only impairs motor performance concomitant with the pharmacodynamics of the drug, but also impairs future motor performance once antagonism has been relieved. We have termed this phenomenon “aberrant motor learning” and have suggested that it may contribute to motor symptoms in movement disorders such as Parkinson's disease (PD). Here, we show that chronic nicotine (cNIC), but not acute nicotine, treatment mitigates the acquisition of D2R-antagonist-induced aberrant motor learning in mice. Although cNIC mitigates D2R-mediated aberrant motor learning, cNIC has no effect on D1R-mediated motor learning. β2-containing nicotinic receptors in dopamine neurons likely mediate the protective effect of cNIC against aberrant motor learning, because selective deletion of β2 nicotinic subunits in dopamine neurons reduced D2R-mediated aberrant motor learning. Finally, both cNIC treatment and β2 subunit deletion blunted postsynaptic responses to D2R antagonism. These results suggest that a chronic decrease in function or a downregulation of β2-containing nicotinic receptors protects the striatal network against aberrant plasticity and aberrant motor learning induced by motor experience under dopamine deficiency. SIGNIFICANCE STATEMENT Increasingly, aberrant plasticity and aberrant learning are recognized as contributing to the development and progression of movement disorders. Here, we show that chronic nicotine (cNIC) treatment or specific deletion of β2 nicotinic receptor subunits in dopamine neurons mitigates aberrant motor learning induced by dopamine D2 receptor (D2R) blockade in mice. Moreover, both manipulations also reduced striatal dopamine release and blunt postsynaptic responses to D2R antagonists. These results suggest that chronic downregulation of

  3. Rooting Out Aberrant Behavior in Training.

    ERIC Educational Resources Information Center

    Kokalis, Jerry, Jr.; Paquin, Dave

    1989-01-01

    Discusses aberrant, or disruptive, behavior in an industrial/business, classroom-based, instructor-led training setting. Three examples of aberrant behavior are described, typical case studies are provided for each, and preventive (long-term) and corrective (on-the-spot) strategies for dealing with the problems are discussed. (LRW)

  4. Using aberrant behaviors as reinforcers for autistic children.

    PubMed Central

    Charlop, M H; Kurtz, P F; Casey, F G

    1990-01-01

    In a series of experiments, we assessed the efficacy of using autistic children's aberrant behaviors as reinforcers to increase their correct task responding. In Experiment 1, reinforcer conditions of stereotypy, food, and varied (food or stereotypy) were compared. In Experiment 2, the conditions were delayed echolalia, food, and varied (food or delayed echolalia), and in Experiment 3, perseverative behavior was compared with stereotypy and food as potential reinforcers. A multielement design was used for all comparisons, and side-effect measures were recorded during and after teaching sessions as well as at home. Results indicated that, in general, task performance was highest when brief opportunities to engage in aberrant behaviors were provided as reinforcers. Edibles were associated with the lowest performance. Furthermore, no negative side effects (e.g., an increase in aberrant behaviors) occurred. The results are discussed in terms of suggesting a more pragmatic treatment approach by addressing the contingent use of autistic children's aberrant behaviors as reinforcers. PMID:2373653

  5. Persistence of Early Emerging Aberrant Behavior in Children with Developmental Disabilities

    ERIC Educational Resources Information Center

    Green, Vanessa A.; O'Reilly, Mark; Itchon, Jonathan; Sigafoos, Jeff

    2005-01-01

    This study examined the persistence of early emerging aberrant behavior in 13 preschool children with developmental disabilities. The severity of aberrant behavior was assessed every 6 months over a 3-year period. Teachers completed the assessments using the Aberrant Behavior Checklist [Aman, M. G., & Singh, N. N. (1986). "Aberrant…

  6. Effect of Training Different Classes of Verbal Behavior to Decrease Aberrant Verbal Behavior

    PubMed Central

    Vandbakk, Monica; Arntzen, Erik; Gisnaas, Arnt; Antonsen, Vidar; Gundhus, Terje

    2012-01-01

    Inappropriate verbal behavior that is labeled “psychotic” is often described as insensitive to environmental contingencies. The purpose of the current study was to establish different classes of rational or appropriate verbal behavior in a woman with developmental disabilities and evaluate the effects on her psychotic or aberrant vocal verbal behavior. Similar to a previous study (Arntzen, Ro Tonnessen, & Brouwer, 2006), the results of the current study suggested that the procedure helped to establish a repertoire of appropriate functional vocal verbal behavior in the participant. Overall, the results suggested the effectiveness of an intervention based on training various classes of verbal behavior in decreasing aberrant verbal behavior. PMID:22754112

  7. Effect of training different classes of verbal behavior to decrease aberrant verbal behavior.

    PubMed

    Vandbakk, Monica; Arntzen, Erik; Gisnaas, Arnt; Antonsen, Vidar; Gundhus, Terje

    2012-01-01

    Inappropriate verbal behavior that is labeled "psychotic" is often described as insensitive to environmental contingencies. The purpose of the current study was to establish different classes of rational or appropriate verbal behavior in a woman with developmental disabilities and evaluate the effects on her psychotic or aberrant vocal verbal behavior. Similar to a previous study (Arntzen, Ro Tonnessen, & Brouwer, 2006), the results of the current study suggested that the procedure helped to establish a repertoire of appropriate functional vocal verbal behavior in the participant. Overall, the results suggested the effectiveness of an intervention based on training various classes of verbal behavior in decreasing aberrant verbal behavior.

  8. Using Aberrant Behaviors as Reinforcers for Autistic Children.

    ERIC Educational Resources Information Center

    Charlop, Marjorie H.; And Others

    1990-01-01

    Three experiments assessed the efficacy of various reinforcers to increase correct task responding in a total of 10 autistic children, aged 6-9. Of the reinforcers used (stereotypy, delayed echolalia, perseverative behavior, and food), task performance was highest with opportunities to engage in aberrant behaviors, and lowest with edible…

  9. Lack of GPR88 enhances medium spiny neuron activity and alters motor- and cue-dependent behaviors.

    PubMed

    Quintana, Albert; Sanz, Elisenda; Wang, Wengang; Storey, Granville P; Güler, Ali D; Wanat, Matthew J; Roller, Bryan A; La Torre, Anna; Amieux, Paul S; McKnight, G Stanley; Bamford, Nigel S; Palmiter, Richard D

    2012-11-01

    The striatum regulates motor control, reward and learning. Abnormal function of striatal GABAergic medium spiny neurons (MSNs) is believed to contribute to the deficits in these processes that are observed in many neuropsychiatric diseases. The orphan G protein-coupled receptor GPR88 is robustly expressed in MSNs and is regulated by neuropharmacological drugs, but its contribution to MSN physiology and behavior is unclear. We found that, in the absence of GPR88, MSNs showed increased glutamatergic excitation and reduced GABAergic inhibition, which promoted enhanced firing rates in vivo, resulting in hyperactivity, poor motor coordination and impaired cue-based learning in mice. Targeted viral expression of GPR88 in MSNs rescued the molecular and electrophysiological properties and normalized behavior, suggesting that aberrant MSN activation in the absence of GPR88 underlies behavioral deficits and its dysfunction may contribute to behaviors observed in neuropsychiatric disease.

  10. The development of motor behavior

    PubMed Central

    Adolph, Karen E.; Franchak, John M.

    2016-01-01

    This article reviews research on the development of motor behavior from a developmental systems perspective. We focus on infancy when basic action systems are acquired. Posture provides a stable base for locomotion, manual actions, and facial actions. Experience facilitates improvements in motor behavior and infants accumulate immense amounts of experience with all of their basic action systems. At every point in development, perception guides motor behavior by providing feedback about the results of just prior movements and information about what to do next. Reciprocally, the development of motor behavior provides fodder for perception. More generally, motor development brings about new opportunities for acquiring knowledge about the world, and burgeoning motor skills can instigate cascades of developmental changes in perceptual, cognitive, and social domains. PMID:27906517

  11. Effect of Training Different Classes of Verbal Behavior to Decrease Aberrant Verbal Behavior

    ERIC Educational Resources Information Center

    Vandbakk, Monica; Arntzen, Erik; Gisnaas, Arnt; Antonsen, Vidar; Gundhus, Terje

    2012-01-01

    Inappropriate verbal behavior that is labeled "psychotic" is often described as insensitive to environmental contingencies. The purpose of the current study was to establish different classes of rational or appropriate verbal behavior in a woman with developmental disabilities and evaluate the effects on her psychotic or aberrant vocal verbal…

  12. Crash risk and aberrant driving behaviors among bus drivers: the role of personality and attitudes towards traffic safety.

    PubMed

    Mallia, Luca; Lazuras, Lambros; Violani, Cristiano; Lucidi, Fabio

    2015-06-01

    Several studies have shown that personality traits and attitudes toward traffic safety predict aberrant driving behaviors and crash involvement. However, this process has not been adequately investigated in professional drivers, such as bus drivers. The present study used a personality-attitudes model to assess whether personality traits predicted aberrant self-reported driving behaviors (driving violations, lapses, and errors) both directly and indirectly, through the effects of attitudes towards traffic safety in a large sample of bus drivers. Additionally, the relationship between aberrant self-reported driving behaviors and crash risk was also assessed. Three hundred and one bus drivers (mean age=39.1, SD=10.7 years) completed a structured and anonymous questionnaire measuring personality traits, attitudes toward traffic safety, self-reported aberrant driving behaviors (i.e., errors, lapses, and traffic violations), and accident risk in the last 12 months. Structural equation modeling analysis revealed that personality traits were associated to aberrant driving behaviors both directly and indirectly. In particular altruism, excitement seeking, and normlessness directly predicted bus drivers' attitudes toward traffic safety which, in turn, were negatively associated with the three types of self-reported aberrant driving behaviors. Personality traits relevant to emotionality directly predicted bus drivers' aberrant driving behaviors, without any mediation of attitudes. Finally, only self-reported violations were related to bus drivers' accident risk. The present findings suggest that the hypothesized personality-attitudes model accounts for aberrant driving behaviors in bus drivers, and provide the empirical basis for evidence-based road safety interventions in the context of public transport. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. How does environmental enrichment reduce repetitive motor behaviors? Neuronal activation and dendritic morphology in the indirect basal ganglia pathway of a mouse model

    PubMed Central

    Bechard, Allison R.; Cacodcar, Nadia; King, Michael A.; Lewis, Mark H.

    2015-01-01

    Repetitive motor behaviors are observed in many neurodevelopmental and neurological disorders (e.g. autism spectrum disorders, Tourette syndrome, fronto-temporal dementia). Despite their clinical importance, the neurobiology underlying these highly stereotyped, apparently functionless behaviors is poorly understood. Identification of mechanisms that mediate the development of repetitive behaviors will aid in the discovery of new therapeutic targets and treatment development. Using a deer mouse model, we have shown that decreased indirect basal ganglia pathway activity is associated with high levels of repetitive behavior. Environmental enrichment (EE) markedly attenuates the development of such aberrant behaviors in mice, although mechanisms driving this effect are unknown. We hypothesized that EE would reduce repetitive motor behaviors by increasing indirect basal ganglia pathway function. We assessed neuronal activation and dendritic spine density in basal ganglia of adult deer mice reared in EE and standard housing. Significant increases in neuronal activation and dendritic spine densities were observed only in the subthalamic nucleus (STN) and globus pallidus (GP), and only for those mice that exhibited an EE-induced decrease in repetitive motor behavior. As the STN and GP lie within the indirect pathway, these data suggest that EE-induced attenuation of repetitive motor behaviors is associated with increased functional activation of the indirect basal ganglia pathway. These results are consistent with our other findings highlighting the importance of the indirect pathway in mediating repetitive motor behaviors. PMID:26620495

  14. Predicting aberrant drug behavior in patients treated for chronic pain: importance of abuse history.

    PubMed

    Michna, Edward; Ross, Edgar L; Hynes, Wilfred L; Nedeljkovic, Srdjan S; Soumekh, Sharonah; Janfaza, David; Palombi, Diane; Jamison, Robert N

    2004-09-01

    Physicians can encounter problems in prescribing opioids for some patients with chronic pain such as multiple unsanctioned dose escalations, episodes of lost or stolen prescriptions, and positive urine drug screenings for illicit substances. This study explored the usefulness of questions on abuse history in predicting problems with prescribing opioids for patients at a hospital-based pain management program. One hundred forty-five (145) patients who were taking long- and short-acting opioids for their pain were classified as high or low risk on the basis of their responses to interview questions about 1) substance abuse history in their family, 2) past problems with drug or alcohol abuse, and 3) history of legal problems. The treating physicians completed a questionnaire about problems that they had encountered with their patients. Problem behaviors were verified through chart review. No differences in demographic characteristics were found between those classified as high and low risk. Patients who admitted to a family history of substance abuse, a history of legal problems, and drug or alcohol abuse were prone to more aberrant drug-related behaviors, including a higher incidence of lost or stolen prescriptions and the presence of illicit substances in their urine (P < 0.05). Patients classified as high risk also had a significantly higher frequency of reported mental health problems and motor vehicle accidents. More of these patients smoked cigarettes, tended to need a cigarette within the first hour of the day, took higher doses of opioids, and reported fewer adverse effects from the medications than did those without such a history (P < 0.05). This study demonstrates that questions about abuse history and legal problems can be useful in predicting aberrant drug-related behavior with opioid use in persons with chronic noncancer pain.

  15. Aberrant Neuromagnetic Activation in the Motor Cortex in Children with Acute Migraine: A Magnetoencephalography Study

    PubMed Central

    Guo, Xinyao; Xiang, Jing; Wang, Yingying; O’Brien, Hope; Kabbouche, Marielle; Horn, Paul; Powers, Scott W.; Hershey, Andrew D.

    2012-01-01

    Migraine attacks have been shown to interfere with normal function in the brain such as motor or sensory function. However, to date, there has been no clinical neurophysiology study focusing on the motor function in children with migraine during headache attacks. To investigate the motor function in children with migraine, twenty-six children with acute migraine, meeting International Classification of Headache Disorders criteria and age- and gender-matched healthy children were studied using a 275-channel magnetoencephalography system. A finger-tapping paradigm was designed to elicit neuromagnetic activation in the motor cortex. Children with migraine showed significantly prolonged latency of movement-evoked magnetic fields (MEF) during finger movement compared with the controls. The correlation coefficient of MEF latency and age in children with migraine was significantly different from that in healthy controls. The spectral power of high gamma (65–150 Hz) oscillations during finger movement in the primary motor cortex is also significantly higher in children with migraine than in controls. The alteration of responding latency and aberrant high gamma oscillations suggest that the developmental trajectory of motor function in children with migraine is impaired during migraine attacks and/or developmentally delayed. This finding indicates that childhood migraine may affect the development of brain function and result in long-term problems. PMID:23185541

  16. A variation of noncontingent reinforcement in the treatment of aberrant behavior.

    PubMed

    Britton, L N; Carr, J E; Kellum, K K; Dozier, C L; Weil, T M

    2000-01-01

    We examined the effectiveness of a variation of noncontingent reinforcement (NCR) that incorporated a stimulus-delay procedure in the reduction of aberrant behavior maintained by positive reinforcement. Functional analyses for three individuals diagnosed with developmental disabilities indicated that their behaviors were maintained by positive reinforcement: one in the form of access to a tangible item, another by attention, and the third by physical contact. We implemented NCR with the delay procedure with two participants using reversal designs to evaluate effects. We also compared this NCR variation and DRO with the third participant to evaluate reinforcer-delivery rates. The variation of NCR was successful in reducing all aberrant behavior to near-zero levels. A comparison of reinforcer delivery between NCR with the stimulus-delay procedure and DRO demonstrated that the participant accessed more reinforcement with NCR. Results are discussed in the context of enhancing decelerative interventions with emphases on minimizing response effort for caregivers and maximizing access to reinforcement for the individuals.

  17. Cerebellar Influence on Motor Cortex Plasticity: Behavioral Implications for Parkinson’s Disease

    PubMed Central

    Kishore, Asha; Meunier, Sabine; Popa, Traian

    2014-01-01

    Normal motor behavior involves the creation of appropriate activity patterns across motor networks, enabling firing synchrony, synaptic integration, and normal functioning of these networks. Strong topography-specific connections among the basal ganglia, cerebellum, and their projections to overlapping areas in the motor cortices suggest that these networks could influence each other’s plastic responses and functions. The defective striatal signaling in Parkinson’s disease (PD) could therefore lead to abnormal oscillatory activity and aberrant plasticity at multiple levels within the interlinked motor networks. Normal striatal dopaminergic signaling and cerebellar sensory processing functions influence the scaling and topographic specificity of M1 plasticity. Both these functions are abnormal in PD and appear to contribute to the abnormal M1 plasticity. Defective motor map plasticity and topographic specificity within M1 could lead to incorrect muscle synergies, which could manifest as abnormal or undesired movements, and as abnormal motor learning in PD. We propose that the loss of M1 plasticity in PD reflects a loss of co-ordination among the basal ganglia, cerebellar, and cortical inputs which translates to an abnormal plasticity of motor maps within M1 and eventually to some of the motor signs of PD. The initial benefits of dopamine replacement therapy on M1 plasticity and motor signs are lost during the progressive course of disease. Levodopa-induced dyskinesias in patients with advanced PD is linked to a loss of M1 sensorimotor plasticity and the attenuation of dyskinesias by cerebellar inhibitory stimulation is associated with restoration of M1 plasticity. Complimentary interventions should target reestablishing physiological communication between the striatal and cerebellar circuits, and within striato-cerebellar loop. This may facilitate correct motor synergies and reduce abnormal movements in PD. PMID:24834063

  18. Longitudinal Trajectories of Aberrant Behavior in Fragile X Syndrome

    PubMed Central

    Hustyi, Kristin M.; Hall, Scott S.; Jo, Booil; Lightbody, Amy A.; Reiss, Allan L.

    2016-01-01

    The Aberrant Behavior Checklist—Community (ABC-C; Aman, Burrow, & Wolford, 1995) has been increasingly adopted as a primary tool for measuring behavioral change in clinical trials for individuals with fragile X syndrome (FXS). To our knowledge, however, no study has documented the longitudinal trajectory of aberrant behaviors in individuals with FXS using the ABC-C. As part of a larger longitudinal study, we examined scores obtained on the ABC-C subscales for 124 children and adolescents (64 males, 60 females) with FXS who had two or more assessments (average interval between assessments was approximately 4 years). Concomitant changes in age-equivalent scores on the Vineland Adaptive Behavior Scales (VABS) were also examined. As expected for an X-linked genetic disorder, males with FXS obtained significantly higher scores on all subscales of the ABC-C and significantly lower age-equivalent scores on the VABS than females with FXS. In both males and females with FXS, scores on the Irritability/Agitation and Hyperactivity/Noncompliance subscales of the ABC-C decreased significantly with age, with little to no change occurring over time on the Lethargy/Social Withdrawal, Stereotypic Behavior, and Inappropriate Speech subscales. The decrease in scores on the Hyperactivity/Noncompliance domain was significantly greater for males than for females. In both males and females, age-equivalent scores on the VABS increased significantly over this developmental period. These results establish a basis upon which to evaluate long-term outcomes from intervention-based research. However, longitudinal direct observational studies are needed to establish whether the severity of problem behavior actually decreases over time in this population. PMID:25129200

  19. Schizotypal Perceptual Aberrations of Time: Correlation between Score, Behavior and Brain Activity

    PubMed Central

    Arzy, Shahar; Mohr, Christine; Molnar-Szakacs, Istvan; Blanke, Olaf

    2011-01-01

    A fundamental trait of the human self is its continuum experience of space and time. Perceptual aberrations of this spatial and temporal continuity is a major characteristic of schizophrenia spectrum disturbances – including schizophrenia, schizotypal personality disorder and schizotypy. We have previously found the classical Perceptual Aberration Scale (PAS) scores, related to body and space, to be positively correlated with both behavior and temporo-parietal activation in healthy participants performing a task involving self-projection in space. However, not much is known about the relationship between temporal perceptual aberration, behavior and brain activity. To this aim, we composed a temporal Perceptual Aberration Scale (tPAS) similar to the traditional PAS. Testing on 170 participants suggested similar performance for PAS and tPAS. We then correlated tPAS and PAS scores to participants' performance and neural activity in a task of self-projection in time. tPAS scores correlated positively with reaction times across task conditions, as did PAS scores. Evoked potential mapping and electrical neuroimaging showed self-projection in time to recruit a network of brain regions at the left anterior temporal cortex, right temporo-parietal junction, and occipito-temporal cortex, and duration of activation in this network positively correlated with tPAS and PAS scores. These data demonstrate that schizotypal perceptual aberrations of both time and space, as reflected by tPAS and PAS scores, are positively correlated with performance and brain activation during self-projection in time in healthy individuals along the schizophrenia spectrum. PMID:21267456

  20. Motor learning in animal models of Parkinson’s Disease: Aberrant synaptic plasticity in the motor cortex

    PubMed Central

    Xu, Tonghui; Wang, Shaofang; Lalchandani, Rupa R.; Ding, Jun B

    2017-01-01

    In Parkinson’s disease (PD), dopamine depletion causes dramatic changes in the brain resulting in debilitating cognitive and motor deficits. PD neuropathology has been restricted to postmortem examinations, which are limited to only a single time point of PD progression. Models of PD where dopamine tone in the brain are chemically or physically disrupted are valuable tools in understanding the mechanisms of the disease. The basal ganglia have been well studied in the context of PD, and circuit changes in response to dopamine loss have been linked to the motor dysfunctions in PD. However, the etiology of the cognitive dysfunctions that are comorbid in PD patients has remained unclear until now. In this paper, we review recent studies exploring how dopamine depletion affects the motor cortex at the synaptic level. In particular, we highlight our recent findings on abnormal spine dynamics in the motor cortex of PD mouse models through in vivo, time-lapse imaging and motor-skill behavior assays. In combination with previous studies, a role of the motor cortex in skill-learning, and the impairment of this ability with the loss of dopamine, is becoming more apparent. Taken together, we conclude with a discussion on the potential role for the motor cortex in the motor-skill learning and cognitive impairments of PD, with the possibility of targeting the motor cortex for future PD therapeutics. PMID:28343366

  1. Validity of the Aberrant Behavior Checklist in a Clinical Sample of Toddlers

    ERIC Educational Resources Information Center

    Karabekiroglu, Koray; Aman, Michael G.

    2009-01-01

    We investigated the congruent and criterion validity of the Aberrant Behavior Checklist (ABC) in a clinical sample of toddlers seen over 1 year in Turkey. All consecutive patients (N = 93), 14-43 months old (mean, 30.6 mos.), in a child psychiatry outpatient clinic were included. The ABC, Autism Behavior Checklist (AuBC), and Child Behavior…

  2. A Behavior Analytic Approach to Exploratory Motor Behavior: How Can Caregivers Teach EM Behavior to Infants with Down Syndrome?

    ERIC Educational Resources Information Center

    Bauer, Sara M.; Jones, Emily A.

    2014-01-01

    Impairment in exploratory motor (EM) behavior is part of the Down syndrome behavioral phenotype. Exploratory motor behavior may be a pivotal skill for early intervention with infants with Down syndrome. Exploratory motor impairments are often attributed to general delays in motor development in infants with Down syndrome. A behavior analytic…

  3. Motor-Behavioral Episodes in REM Sleep Behavior Disorder and Phasic Events During REM Sleep

    PubMed Central

    Manni, Raffaele; Terzaghi, Michele; Glorioso, Margaret

    2009-01-01

    Study Objectives: To investigate if sudden-onset motor-behavioral episodes in REM sleep behavior disorder (RBD) are associated with phasic events of REM sleep, and to explore the potential meaning of such an association. Design: Observational review analysis. Setting: Tertiary sleep center. Patients: Twelve individuals (11 males; mean age 67.6 ± 7.4 years) affected by idiopathic RBD, displaying a total of 978 motor-behavioral episodes during nocturnal in-laboratory video-PSG. Interventions: N/A Measurements and Results: The motor activity displayed was primitive in 69.1% and purposeful/semi-purposeful in 30.9% of the motor-behavioral episodes recorded. Sleeptalking was significantly more associated with purposeful/semi-purposeful motor activity than crying and/or incomprehensible muttering (71.0% versus 21.4%, P < 0.005). In 58.2% of the motor-behavioral episodes, phasic EEG-EOG events (rapid eye movements [REMs], α bursts, or sawtooth waves [STWs]) occurred simultaneously. Each variable (REMs, STWs, α bursts) was associated more with purposeful/semi-purposeful than with primitive movements (P < 0.05). Conclusions: Motor-behavioral episodes in RBD were significantly more likely to occur in association with phasic than with tonic periods of REM sleep. The presence of REMs, α bursts and STWs was found to be more frequent in more complex episodes. We hypothesize that motor-behavioral episodes in RBD are likely to occur when the brain, during REM sleep, is in a state of increased instability (presence of α bursts) and experiencing stronger stimulation of visual areas (REMs). Citation: Manni R; Terzaghi M; Glorioso M. Motor-behavioral episodes in REM sleep behavior disorder and phasic events during REM sleep. SLEEP 2009;32(2):241–245. PMID:19238811

  4. Aberrant functional connectivity between motor and language networks in rolandic epilepsy.

    PubMed

    Besseling, René M H; Overvliet, Geke M; Jansen, Jacobus F A; van der Kruijs, Sylvie J M; Vles, Johannes S H; Ebus, Saskia C M; Hofman, Paul A M; de Louw, Anton J A; Aldenkamp, Albert P; Backes, Walter H

    2013-12-01

    Rolandic epilepsy (RE) is an idiopathic focal childhood epilepsy with a well-established neuropsychological profile of language impairment. The aim of this study is to provide a functional correlate that links rolandic (sensorimotor) pathology to language problems using functional MRI. Twenty-three children with RE (8-14 years old) and 21 matched controls underwent extensive language assessment (Clinical Evaluation of Language Fundamentals). fMRI was performed at rest and using word generation, reading, and finger tapping paradigms. Since no activation group differences were found, regions of interest (ROIs) were defined at pooled (patients and controls combined) activation maxima and in contralateral homotopic cortex, and used to assess language lateralization as well as for a resting-state connectivity analysis. Furthermore, the association between connection strength and language performance was investigated. Reduced language performance was found in the children with RE. Bilateral activation was found for both language tasks with some predominance of the left hemisphere in both groups. Compared to controls, patient connectivity was decreased between the left sensorimotor area and right inferior frontal gyrus (p<0.01). For this connection, lower connectivity was associated with lower language scores in the patient group (r=0.49, p=0.02), but not in the controls. Language laterality analysis revealed bilateral language representation in the age range under study (8-14 years). As a consequence, the connection of reduced functional connectivity we found represents an impaired interplay between motor and language networks, and aberrant functional connectivity associated with poorer language performance. These findings provide a first neuronal correlate in terms of aberrant resting-state functional connectivity for language impairment in RE. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Lateralized hyperkinetic motor behavior.

    PubMed

    Krishnaiah, Balaji; Acharya, Jayant; Ahmed, Aiesha

    2018-01-01

    Seizures are followed by a post-ictal period, which is characterized by usual slowing of brain activity. This case report describes a 68-year old woman who presented with right-sided rhythmic, non-voluntary, semi-purposeful motor behavior that started 2 days after an episode of generalized seizure. Her initial electroencephalogram (EEG) showed beta activity with no evidence of epileptiform discharges. Computed tomography scan showed hypodensity in the left parieto-occipital region. Magnetic resonance imaging (MRI) showed restricted diffusion/fluid-attenuated inversion recovery hyperintensities in the left precentral and post-central gyrus. Unilateral compulsive motor behavior during the post-ictal state should be considered, and not confused with partial status epilepticus to avoid unnecessary treatment. Abnormal magnetic resonance imaging (MRI) findings, which are reversible, can help with the diagnostic and therapeutic approach.

  6. Optimality, stochasticity, and variability in motor behavior

    PubMed Central

    Guigon, Emmanuel; Baraduc, Pierre; Desmurget, Michel

    2008-01-01

    Recent theories of motor control have proposed that the nervous system acts as a stochastically optimal controller, i.e. it plans and executes motor behaviors taking into account the nature and statistics of noise. Detrimental effects of noise are converted into a principled way of controlling movements. Attractive aspects of such theories are their ability to explain not only characteristic features of single motor acts, but also statistical properties of repeated actions. Here, we present a critical analysis of stochastic optimality in motor control which reveals several difficulties with this hypothesis. We show that stochastic control may not be necessary to explain the stochastic nature of motor behavior, and we propose an alternative framework, based on the action of a deterministic controller coupled with an optimal state estimator, which relieves drawbacks of stochastic optimality and appropriately explains movement variability. PMID:18202922

  7. Perceptual-Motor Behavior and Educational Processes.

    ERIC Educational Resources Information Center

    Cratty, Bryant J.

    Addressed to elementary school and special class teachers, the text presents research-based information on perceptual-motor behavior and education, including movement and the human personality, research guidelines, and movement activities in general education. Special education is considered and perceptual motor abilities are discussed with…

  8. Recruitment of rat diaphragm motor units across motor behaviors with different levels of diaphragm activation.

    PubMed

    Seven, Yasin B; Mantilla, Carlos B; Sieck, Gary C

    2014-12-01

    Phrenic motor neurons are recruited across a range of motor behaviors to generate varying levels of diaphragm muscle (DIAm) force. We hypothesized that DIAm motor units are recruited in a fixed order across a range of motor behaviors of varying force levels, consistent with the Henneman Size Principle. Single motor unit action potentials and compound DIAm EMG activities were recorded in anesthetized, neurally intact rats across different motor behaviors, i.e., eupnea, hypoxia-hypercapnia (10% O2 and 5% CO2), deep breaths, sustained airway occlusion, and sneezing. Central drive [estimated by root-mean-squared (RMS) EMG value 75 ms after the onset of EMG activity (RMS75)], recruitment delay, and onset discharge frequencies were similar during eupnea and hypoxia-hypercapnia. Compared with eupnea, central drive increased (∼25%) during deep breaths, and motor units were recruited ∼12 ms earlier (P < 0.01). During airway occlusion, central drive was ∼3 times greater, motor units were recruited ∼30 ms earlier (P < 0.01), and motor unit onset discharge frequencies were significantly higher (P < 0.01). Recruitment order of motor unit pairs observed during eupnea was maintained for 98%, 87%, and 84% of the same pairs recorded during hypoxia-hypercapnia, deep breaths, and airway occlusion, respectively. Reversals in motor unit recruitment order were observed primarily if motor unit pairs were recruited <20 ms apart. These results are consistent with DIAm motor unit recruitment order being determined primarily by the intrinsic size-dependent electrophysiological properties of phrenic motor neurons. Copyright © 2014 the American Physiological Society.

  9. Recruitment of rat diaphragm motor units across motor behaviors with different levels of diaphragm activation

    PubMed Central

    Seven, Yasin B.; Mantilla, Carlos B.

    2014-01-01

    Phrenic motor neurons are recruited across a range of motor behaviors to generate varying levels of diaphragm muscle (DIAm) force. We hypothesized that DIAm motor units are recruited in a fixed order across a range of motor behaviors of varying force levels, consistent with the Henneman Size Principle. Single motor unit action potentials and compound DIAm EMG activities were recorded in anesthetized, neurally intact rats across different motor behaviors, i.e., eupnea, hypoxia-hypercapnia (10% O2 and 5% CO2), deep breaths, sustained airway occlusion, and sneezing. Central drive [estimated by root-mean-squared (RMS) EMG value 75 ms after the onset of EMG activity (RMS75)], recruitment delay, and onset discharge frequencies were similar during eupnea and hypoxia-hypercapnia. Compared with eupnea, central drive increased (∼25%) during deep breaths, and motor units were recruited ∼12 ms earlier (P < 0.01). During airway occlusion, central drive was ∼3 times greater, motor units were recruited ∼30 ms earlier (P < 0.01), and motor unit onset discharge frequencies were significantly higher (P < 0.01). Recruitment order of motor unit pairs observed during eupnea was maintained for 98%, 87%, and 84% of the same pairs recorded during hypoxia-hypercapnia, deep breaths, and airway occlusion, respectively. Reversals in motor unit recruitment order were observed primarily if motor unit pairs were recruited <20 ms apart. These results are consistent with DIAm motor unit recruitment order being determined primarily by the intrinsic size-dependent electrophysiological properties of phrenic motor neurons. PMID:25257864

  10. Aberrant supplementary motor complex and limbic activity during motor preparation in motor conversion disorder

    PubMed Central

    Voon, V; Brezing, C; Gallea, C; Hallett, M

    2014-01-01

    Background Conversion disorder is characterized by unexplained neurological symptoms presumed related to psychological issues. The main hypotheses to explain conversion paralysis, characterized by a lack of movement, include impairments in either motor intention or disruption of motor execution, and further, that hyperactive self-monitoring, limbic processing or top-down regulation from higher order frontal regions may interfere with motor execution. We have recently shown that conversion disorder with positive abnormal or excessive motor symptoms was associated with greater amygdala activity to arousing stimuli along with greater functional connectivity between the amgydala and supplementary motor area. Here we studied patients with such symptoms focusing on motor initiation. Methods Subjects performed either an internally or externally generated two-button action selection task in a functional MRI study. Results Eleven conversion disorder patients without major depression and 11 age- and gender-matched normal volunteers were assessed. During both internally and externally generated movement, conversion disorder patients relative to normal volunteers had lower left supplementary motor area (SMA) (implicated in motor initiation) and higher right amygdala, left anterior insula and bilateral posterior cingulate activity (implicated in assigning emotional salience). These findings were confirmed in a subgroup analysis of patients with tremor symptoms. During internally versus externally generated action in CD patients, the left SMA had lower functional connectivity with bilateral dorsolateral prefrontal cortices. Conclusion We propose a theory in which previously mapped conversion motor representations may in an arousing context hijack the voluntary action selection system which is both hypoactive and functionally disconnected from prefrontal top-down regulation. PMID:21935985

  11. Aberrant supplementary motor complex and limbic activity during motor preparation in motor conversion disorder.

    PubMed

    Voon, Valerie; Brezing, Christina; Gallea, Cecile; Hallett, Mark

    2011-11-01

    Conversion disorder (CD) is characterized by unexplained neurological symptoms presumed related to psychological issues. The main hypotheses to explain conversion paralysis, characterized by a lack of movement, include impairments in either motor intention or disruption of motor execution, and further, that hyperactive self-monitoring, limbic processing or top-down regulation from higher order frontal regions may interfere with motor execution. We have recently shown that CD with positive abnormal or excessive motor symptoms was associated with greater amygdala activity to arousing stimuli along with greater functional connectivity between the amygdala and supplementary motor area. Here we studied patients with such symptoms focusing on motor initiation. Subjects performed either an internally or externally generated 2-button action selection task in a functional MRI study. Eleven CD patients without major depression and 11 age- and gender-matched normal volunteers were assessed. During both internally and externally generated movement, conversion disorder patients relative to normal volunteers had lower left supplementary motor area (SMA) (implicated in motor initiation) and higher right amygdala, left anterior insula, and bilateral posterior cingulate activity (implicated in assigning emotional salience). These findings were confirmed in a subgroup analysis of patients with tremor symptoms. During internally versus externally generated action in CD patients, the left SMA had lower functional connectivity with bilateral dorsolateral prefrontal cortices. We propose a theory in which previously mapped conversion motor representations may in an arousing context hijack the voluntary action selection system, which is both hypoactive and functionally disconnected from prefrontal top-down regulation. Copyright © 2011 Movement Disorder Society.

  12. Validity of the Aberrant Behavior Checklist in Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Kaat, Aaron J.; Lecavalier, Luc; Aman, Michael G.

    2014-01-01

    The Aberrant Behavior Checklist (ABC) is a widely used measure in autism spectrum disorder (ASD) treatment studies. We conducted confirmatory and exploratory factor analyses of the ABC in 1,893 children evaluated as part of the Autism Treatment Network. The root mean square error of approximation was .086 for the standard item assignment, and in…

  13. Engagement of the Rat Hindlimb Motor Cortex across Natural Locomotor Behaviors.

    PubMed

    DiGiovanna, Jack; Dominici, Nadia; Friedli, Lucia; Rigosa, Jacopo; Duis, Simone; Kreider, Julie; Beauparlant, Janine; van den Brand, Rubia; Schieppati, Marco; Micera, Silvestro; Courtine, Grégoire

    2016-10-05

    Contrary to cats and primates, cortical contribution to hindlimb locomotor movements is not critical in rats. However, the importance of the motor cortex to regain locomotion after neurological disorders in rats suggests that cortical engagement in hindlimb motor control may depend on the behavioral context. To investigate this possibility, we recorded whole-body kinematics, muscle synergies, and hindlimb motor cortex modulation in freely moving rats performing a range of natural locomotor procedures. We found that the activation of hindlimb motor cortex preceded gait initiation. During overground locomotion, the motor cortex exhibited consistent neuronal population responses that were synchronized with the spatiotemporal activation of hindlimb motoneurons. Behaviors requiring enhanced muscle activity or skilled paw placement correlated with substantial adjustment in neuronal population responses. In contrast, all rats exhibited a reduction of cortical activity during more automated behavior, such as stepping on a treadmill. Despite the facultative role of the motor cortex in the production of locomotion in rats, these results show that the encoding of hindlimb features in motor cortex dynamics is comparable in rats and cats. However, the extent of motor cortex modulations appears linked to the degree of volitional engagement and complexity of the task, reemphasizing the importance of goal-directed behaviors for motor control studies, rehabilitation, and neuroprosthetics. We mapped the neuronal population responses in the hindlimb motor cortex to hindlimb kinematics and hindlimb muscle synergies across a spectrum of natural locomotion behaviors. Robust task-specific neuronal population responses revealed that the rat motor cortex displays similar modulation as other mammals during locomotion. However, the reduced motor cortex activity during more automated behaviors suggests a relationship between the degree of engagement and task complexity. This relationship

  14. Children with behavioral problems and motor problems have a worse neurological condition than children with behavioral problems only.

    PubMed

    Peters, Lieke H J; Maathuis, Carel G B; Hadders-Algra, Mijna

    2014-12-01

    Some evidence suggests that children with specific behavioral problems are at risk for motor problems. It is unclear whether neurological condition plays a role in the propensity of children with behavioral problems to develop motor problems. To examine the relation between behavioral problems, motor performance and neurological condition in school-aged children. Cross-sectional study. 174 children (95 boys) receiving mainstream education and 106 children (82 boys) receiving special education aged 6 to 13 years (mean 9 y 7 m, SD 1 y 10 m). Behavior was assessed with questionnaires: the parental Child Behavior Checklist (CBCL) and Teacher's Report Form (TRF). Motor performance was assessed with the Movement Assessment Battery for Children (MABC). MABC-scores ≥5th percentile were considered as age-adequate and scores <5th percentile indicated definite motor problems. Neurological condition was assessed in terms of Minor Neurological Dysfunction (MND). The majority of specific behavioral problems were associated with definite motor problems, except somatic complaints and rule breaking behavior. Children with externalizing problems, according to the CBCL or TRF, and motor problems had more often MND than children with externalizing problems only. The same holds true for internalizing problems according to the CBCL. The present study demonstrated that various forms of behavioral problems were associated with motor problems. Especially children with motor and behavioral problems showed MND. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Obsessive-compulsive disorder: a disorder of pessimal (non-functional) motor behavior.

    PubMed

    Zor, R; Keren, H; Hermesh, H; Szechtman, H; Mort, J; Eilam, D

    2009-10-01

    To determine whether in addition to repetitiveness, the motor rituals of patients with obsessive-compulsive disorder (OCD) involve reduced functionality due to numerous and measurable acts that are irrelevant and unnecessary for task completion. Comparing motor rituals of OCD patients with behavior of non-patient control individuals who were instructed to perform the same motor task. Obsessive-compulsive disorder behavior comprises abundant acts that were not performed by the controls. These acts seem unnecessary or even irrelevant for the task that the patients were performing, and therefore are termed 'non-functional'. Non-functional acts comprise some 60% of OCD motor behavior. Moreover, OCD behavior consists of short chains of functional acts bounded by long chains of non-functional acts. The abundance of irrelevant or unnecessary acts in OCD motor rituals represents reduced functionality in terms of task completion, typifying OCD rituals as pessimal behavior (antonym of optimal behavior).

  16. Factor Analysis of the Aberrant Behavior Checklist in Individuals with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Brinkley, Jason; Nations, Laura; Abramson, Ruth K.; Hall, Alicia; Wright, Harry H.; Gabriels, Robin; Gilbert, John R.; Pericak-Vance, Margaret A. O.; Cuccaro, Michael L.

    2007-01-01

    Exploratory factor analysis (varimax and promax rotations) of the aberrant behavior checklist-community version (ABC) in 275 individuals with Autism spectrum disorder (ASD) identified four- and five-factor solutions which accounted for greater than 70% of the variance. Confirmatory factor analysis (Lisrel 8.7) revealed indices of moderate fit for…

  17. Neonatal stroke causes poor midline motor behaviors and poor fine and gross motor skills during early infancy.

    PubMed

    Chen, Chao-Ying; Lo, Warren D; Heathcock, Jill C

    2013-03-01

    Upper extremity movements, midline behaviors, fine, and gross motor skills are frequently impaired in hemiparesis and cerebral palsy. We investigated midline toy exploration and fine and gross motor skills in infants at risk for hemiplegic cerebral palsy. Eight infants with neonatal stroke (NS) and thirteen infants with typical development (TD) were assessed from 2 to 7 months of age. The following variables were analyzed: percentage of time in midline and fine and gross motor scores on the Bayley Scales of Infant Development (BSID-III). Infants with neonatal stroke demonstrated poor performance in midline behaviors and fine and gross motor scores on the BSID-III. These results suggest that infants with NS have poor midline behaviors and motor skill development early in infancy. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Motor neuronal activity varies least among individuals when it matters most for behavior

    PubMed Central

    Cullins, Miranda J.; Shaw, Kendrick M.; Gill, Jeffrey P.

    2014-01-01

    How does motor neuronal variability affect behavior? To explore this question, we quantified activity of multiple individual identified motor neurons mediating biting and swallowing in intact, behaving Aplysia californica by recording from the protractor muscle and the three nerves containing the majority of motor neurons controlling the feeding musculature. We measured multiple motor components: duration of the activity of identified motor neurons as well as their relative timing. At the same time, we measured behavioral efficacy: amplitude of grasping movement during biting and amplitude of net inward food movement during swallowing. We observed that the total duration of the behaviors varied: Within animals, biting duration shortened from the first to the second and third bites; between animals, biting and swallowing durations varied. To study other sources of variation, motor components were divided by behavior duration (i.e., normalized). Even after normalization, distributions of motor component durations could distinguish animals as unique individuals. However, the degree to which a motor component varied among individuals depended on the role of that motor component in a behavior. Motor neuronal activity that was essential for the expression of biting or swallowing was similar among animals, whereas motor neuronal activity that was not essential for that behavior varied more from individual to individual. These results suggest that motor neuronal activity that matters most for the expression of a particular behavior may vary least from individual to individual. Shaping individual variability to ensure behavioral efficacy may be a general principle for the operation of motor systems. PMID:25411463

  19. Links between motor control and classroom behaviors: Moderation by low birth weight

    PubMed Central

    Razza, Rachel A.; Martin, Anne; Brooks-Gunn, Jeanne

    2016-01-01

    It is unclear from past research on effortful control whether one of its components, motor control, independently contributes to adaptive classroom behaviors. The goal of this study was to identify associations between early motor control, measured by the walk-a-line task at age 3, and teacher-reported learning-related behaviors (approaches to learning and attention problems) and behavior problems in kindergarten classrooms. Models tested whether children who were vulnerable to poorer learning behaviors and more behavior problems due to having been born low birth weight benefited more, less, or the same as other children from better motor control. Data were drawn from the national Fragile Families and Child-Wellbeing Study (n = 751). Regression models indicated that motor control was significantly associated with better approaches to learning and fewer behavior problems. Children who were low birth weight benefitted more than normal birth weight children from better motor control with respect to their approaches to learning, but equally with respect to behavior problems. Additionally, for low but not normal birth weight children, better motor control predicted fewer attention problems. These findings suggest that motor control follows a compensatory model of development for low birth weight children and classroom behaviors. PMID:27594776

  20. Effect of the home environment on motor and cognitive behavior of infants.

    PubMed

    Miquelote, Audrei F; Santos, Denise C C; Caçola, Priscila M; Montebelo, Maria Imaculada de L; Gabbard, Carl

    2012-06-01

    Although information is sparse, research suggests that affordances in the home provide essential resources that promote motor and cognitive skills in young children. The present study assessed over time, the association between motor affordances in the home and infant motor and cognitive behavior. Thirty-two (32) infants were assessed for characteristics of their home using the Affordances in the Home Environment for Motor Development--Infant Scale and motor and cognitive behavior with the Bayley Scales of Infant and Toddler Development--III. Infant's home and motor behavior were assessed at age 9 months and 6 months later with the inclusion of cognitive ability. Results for motor ability indicated that there was an overall improvement in performance from the 1st to the 2nd assessment. We found significant positive correlations between the dimensions of the home (daily activities and play materials) and global motor performance (1st assessment) and fine-motor performance on the 2nd assessment. In regard to cognitive performance (2nd assessment), results indicated a positive association with fine-motor performance. Our results suggest that motor affordances can have a positive impact on future motor ability and speculatively, later cognitive behavior in infants. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Training adaptations in the behavior of human motor units.

    PubMed

    Duchateau, Jacques; Semmler, John G; Enoka, Roger M

    2006-12-01

    The purpose of this brief review is to examine the neural adaptations associated with training, by focusing on the behavior of single motor units. The review synthesizes current understanding on motor unit recruitment and rate coding during voluntary contractions, briefly describes the techniques used to record motor unit activity, and then evaluates the adaptations that have been observed in motor unit activity during maximal and submaximal contractions. Relatively few studies have directly compared motor unit behavior before and after training. Although some studies suggest that the voluntary activation of muscle can increase slightly with strength training, it is not known how the discharge of motor units changes to produce this increase in activation. The evidence indicates that the increase is not attributable to changes in motor unit synchronization. It has been demonstrated, however, that training can increase both the rate of torque development and the discharge rate of motor units. Furthermore, both strength training and practice of a force-matching task can evoke adaptations in the discharge characteristics of motor units. Because the variability in discharge rate has a significant influence on the fluctuations in force during submaximal contractions, the changes produced with training can influence motor performance during activities of daily living. Little is known, however, about the relative contributions of the descending drive, afferent feedback, spinal circuitry, and motor neuron properties to the observed adaptations in motor unit activity.

  2. Cross-species assessments of Motor and Exploratory Behavior related to Bipolar Disorder

    PubMed Central

    Henry, Brook L.; Minassian, Arpi; Young, Jared W.; Paulus, Martin P.; Geyer, Mark A.; Perry, William

    2010-01-01

    Alterations in exploratory behavior are a fundamental feature of bipolar mania, typically characterized as motor hyperactivity and increased goal-directed behavior in response to environmental cues. In contrast, abnormal exploration associated with schizophrenia and depression can manifest as prominent withdrawal, limited motor activity, and inattention to the environment. While motor abnormalities are cited frequently as clinical manifestations of these disorders, relatively few empirical studies have quantified human exploratory behavior. This article reviews the literature characterizing motor and exploratory behavior associated with bipolar disorder and genetic and pharmacological animal models of the illness. Despite sophisticated assessment of exploratory behavior in rodents, objective quantification of human motor activity has been limited primarily to actigraphy studies with poor cross-species translational value. Furthermore, symptoms that reflect the cardinal features of bipolar disorder have proven difficult to establish in putative animal models of this illness. Recently, however, novel tools such as the Human Behavioral Pattern Monitor provide multivariate translational measures of motor and exploratory activity, enabling improved understanding of the neurobiology underlying psychiatric disorders. PMID:20398694

  3. Cross-species assessments of motor and exploratory behavior related to bipolar disorder.

    PubMed

    Henry, Brook L; Minassian, Arpi; Young, Jared W; Paulus, Martin P; Geyer, Mark A; Perry, William

    2010-07-01

    Alterations in exploratory behavior are a fundamental feature of bipolar mania, typically characterized as motor hyperactivity and increased goal-directed behavior in response to environmental cues. In contrast, abnormal exploration associated with schizophrenia and depression can manifest as prominent withdrawal, limited motor activity, and inattention to the environment. While motor abnormalities are cited frequently as clinical manifestations of these disorders, relatively few empirical studies have quantified human exploratory behavior. This article reviews the literature characterizing motor and exploratory behavior associated with bipolar disorder and genetic and pharmacological animal models of the illness. Despite sophisticated assessment of exploratory behavior in rodents, objective quantification of human motor activity has been limited primarily to actigraphy studies with poor cross-species translational value. Furthermore, symptoms that reflect the cardinal features of bipolar disorder have proven difficult to establish in putative animal models of this illness. Recently, however, novel tools such as the human behavioral pattern monitor provide multivariate translational measures of motor and exploratory activity, enabling improved understanding of the neurobiology underlying psychiatric disorders.

  4. A framework to describe, analyze and generate interactive motor behaviors.

    PubMed

    Jarrassé, Nathanaël; Charalambous, Themistoklis; Burdet, Etienne

    2012-01-01

    While motor interaction between a robot and a human, or between humans, has important implications for society as well as promising applications, little research has been devoted to its investigation. In particular, it is important to understand the different ways two agents can interact and generate suitable interactive behaviors. Towards this end, this paper introduces a framework for the description and implementation of interactive behaviors of two agents performing a joint motor task. A taxonomy of interactive behaviors is introduced, which can classify tasks and cost functions that represent the way each agent interacts. The role of an agent interacting during a motor task can be directly explained from the cost function this agent is minimizing and the task constraints. The novel framework is used to interpret and classify previous works on human-robot motor interaction. Its implementation power is demonstrated by simulating representative interactions of two humans. It also enables us to interpret and explain the role distribution and switching between roles when performing joint motor tasks.

  5. A Framework to Describe, Analyze and Generate Interactive Motor Behaviors

    PubMed Central

    Jarrassé, Nathanaël; Charalambous, Themistoklis; Burdet, Etienne

    2012-01-01

    While motor interaction between a robot and a human, or between humans, has important implications for society as well as promising applications, little research has been devoted to its investigation. In particular, it is important to understand the different ways two agents can interact and generate suitable interactive behaviors. Towards this end, this paper introduces a framework for the description and implementation of interactive behaviors of two agents performing a joint motor task. A taxonomy of interactive behaviors is introduced, which can classify tasks and cost functions that represent the way each agent interacts. The role of an agent interacting during a motor task can be directly explained from the cost function this agent is minimizing and the task constraints. The novel framework is used to interpret and classify previous works on human-robot motor interaction. Its implementation power is demonstrated by simulating representative interactions of two humans. It also enables us to interpret and explain the role distribution and switching between roles when performing joint motor tasks. PMID:23226231

  6. The compensatory interaction between motor unit firing behavior and muscle force during fatigue

    PubMed Central

    De Luca, Carlo J.; Kline, Joshua C.

    2016-01-01

    Throughout the literature, different observations of motor unit firing behavior during muscle fatigue have been reported and explained with varieties of conjectures. The disagreement amongst previous studies has resulted, in part, from the limited number of available motor units and from the misleading practice of grouping motor unit data across different subjects, contractions, and force levels. To establish a more clear understanding of motor unit control during fatigue, we investigated the firing behavior of motor units from the vastus lateralis muscle of individual subjects during a fatigue protocol of repeated voluntary constant force isometric contractions. Surface electromyographic decomposition technology provided the firings of 1,890 motor unit firing trains. These data revealed that to sustain the contraction force as the muscle fatigued, the following occurred: 1) motor unit firing rates increased; 2) new motor units were recruited; and 3) motor unit recruitment thresholds decreased. Although the degree of these adaptations was subject specific, the behavior was consistent in all subjects. When we compared our empirical observations with those obtained from simulation, we found that the fatigue-induced changes in motor unit firing behavior can be explained by increasing excitation to the motoneuron pool that compensates for the fatigue-induced decrease in muscle force twitch reported in empirical studies. Yet, the fundamental motor unit control scheme remains invariant throughout the development of fatigue. These findings indicate that the central nervous system regulates motor unit firing behavior by adjusting the operating point of the excitation to the motoneuron pool to sustain the contraction force as the muscle fatigues. PMID:27385798

  7. The compensatory interaction between motor unit firing behavior and muscle force during fatigue.

    PubMed

    Contessa, Paola; De Luca, Carlo J; Kline, Joshua C

    2016-10-01

    Throughout the literature, different observations of motor unit firing behavior during muscle fatigue have been reported and explained with varieties of conjectures. The disagreement amongst previous studies has resulted, in part, from the limited number of available motor units and from the misleading practice of grouping motor unit data across different subjects, contractions, and force levels. To establish a more clear understanding of motor unit control during fatigue, we investigated the firing behavior of motor units from the vastus lateralis muscle of individual subjects during a fatigue protocol of repeated voluntary constant force isometric contractions. Surface electromyographic decomposition technology provided the firings of 1,890 motor unit firing trains. These data revealed that to sustain the contraction force as the muscle fatigued, the following occurred: 1) motor unit firing rates increased; 2) new motor units were recruited; and 3) motor unit recruitment thresholds decreased. Although the degree of these adaptations was subject specific, the behavior was consistent in all subjects. When we compared our empirical observations with those obtained from simulation, we found that the fatigue-induced changes in motor unit firing behavior can be explained by increasing excitation to the motoneuron pool that compensates for the fatigue-induced decrease in muscle force twitch reported in empirical studies. Yet, the fundamental motor unit control scheme remains invariant throughout the development of fatigue. These findings indicate that the central nervous system regulates motor unit firing behavior by adjusting the operating point of the excitation to the motoneuron pool to sustain the contraction force as the muscle fatigues. Copyright © 2016 the American Physiological Society.

  8. Changes in Motor Vehicle Buyer Attitudes and Market Behavior

    DOT National Transportation Integrated Search

    1980-12-01

    An analysis is made of the impact of fuel-efficient motor vehicle design changes on the attitudes and market behavior of buyers of new motor vehicles. Car buyer profiles for selected makes of automobiles describe demographic characteristics, owner sa...

  9. Oxidative Stress, Motor Abilities, and Behavioral Adjustment in Children Treated for Acute Lymphoblastic Leukemia.

    PubMed

    Hockenberry, Marilyn J; Krull, Kevin R; Insel, Kathleen C; Harris, Lynnette L; Gundy, Patricia M; Adkins, Kristin B; Pasvogel, Alice E; Taylor, Olga A; Koerner, Kari M; Montgomery, David W; Ross, Adam K; Hill, Adam; Moore, Ida M

    2015-09-01

    To examine associations among oxidative stress, fine and visual-motor abilities, and behavioral adjustment in children receiving chemotherapy for acute lymphoblastic leukemia (ALL)
. A prospective, repeated-measures design
. Two pediatric oncology settings in the southwestern United States. 89 children with ALL were followed from diagnosis to the end of chemotherapy. Serial cerebrospinal fluid samples were collected during scheduled lumbar punctures and analyzed for oxidative stress biomarkers. Children completed fine motor dexterity, visual processing speed, and visual-motor integration measures at three time points. Parents completed child behavior ratings at the same times. Oxidative stress, fine motor dexterity, visual processing, visual-motor integration, and behavioral adjustment
. Children with ALL had below-average fine motor dexterity, visual processing speed, and visual-motor integration following the induction phase of ALL therapy. By end of therapy, visual processing speed normalized, and fine motor dexterity and visual-motor integration remained below average. Oxidative stress measures correlated with fine motor dexterity and visual-motor integration. Decreased motor functioning was associated with increased hyperactivity and anxiety
. Oxidative stress occurs following chemo-therapy for childhood ALL and is related to impaired fine motor skills and visual symptoms
. Early intervention should be considered to prevent fine motor and visual-spatial deficits, as well as behavioral problems.

  10. Cerebellar Plasticity and Motor Learning Deficits in a Copy Number Variation Mouse Model of Autism

    PubMed Central

    Piochon, Claire; Kloth, Alexander D; Grasselli, Giorgio; Titley, Heather K; Nakayama, Hisako; Hashimoto, Kouichi; Wan, Vivian; Simmons, Dana H; Eissa, Tahra; Nakatani, Jin; Cherskov, Adriana; Miyazaki, Taisuke; Watanabe, Masahiko; Takumi, Toru; Kano, Masanobu; Wang, Samuel S-H; Hansel, Christian

    2014-01-01

    A common feature of autism spectrum disorder (ASD) is the impairment of motor control and learning, occurring in a majority of children with autism, consistent with perturbation in cerebellar function. Here we report alterations in motor behavior and cerebellar synaptic plasticity in a mouse model (patDp/+) for the human 15q11-13 duplication, one of the most frequently observed genetic aberrations in autism. These mice show ASD-resembling social behavior deficits. We find that in patDp/+ mice delay eyeblink conditioning—a form of cerebellum-dependent motor learning—is impaired, and observe deregulation of a putative cellular mechanism for motor learning, long-term depression (LTD) at parallel fiber-Purkinje cell synapses. Moreover, developmental elimination of surplus climbing fibers—a model for activity-dependent synaptic pruning—is impaired. These findings point to deficits in synaptic plasticity and pruning as potential causes for motor problems and abnormal circuit development in autism. PMID:25418414

  11. Validity and Reliability of the "Behavior Problems Inventory," the "Aberrant Behavior Checklist," and the "Repetitive Behavior Scale--Revised" among Infants and Toddlers at Risk for Intellectual or Developmental Disabilities: A Multi-Method Assessment Approach

    ERIC Educational Resources Information Center

    Rojahn, Johannes; Schroeder, Stephen R.; Mayo-Ortega, Liliana; Oyama-Ganiko, Rosao; LeBlanc, Judith; Marquis, Janet; Berke, Elizabeth

    2013-01-01

    Reliable and valid assessment of aberrant behaviors is essential in empirically verifying prevention and intervention for individuals with intellectual or developmental disabilities (IDD). Few instruments exist which assess behavior problems in infants. The current longitudinal study examined the performance of three behavior-rating scales for…

  12. Amelioration of Behavioral Abnormalities in BH4-deficient Mice by Dietary Supplementation of Tyrosine

    PubMed Central

    Kwak, Sang Su; Jeong, Mikyoung; Choi, Ji Hye; Kim, Daesoo; Min, Hyesun; Yoon, Yoosik; Hwang, Onyou; Meadows, Gary G.; Joe, Cheol O.

    2013-01-01

    This study reports an amelioration of abnormal motor behaviors in tetrahydrobiopterin (BH4)-deficient Spr −/− mice by the dietary supplementation of tyrosine. Since BH4 is an essential cofactor for the conversion of phenylalanine into tyrosine as well as the synthesis of dopamine neurotransmitter within the central nervous system, the levels of tyrosine and dopamine were severely reduced in brains of BH4-deficient Spr −/− mice. We found that Spr −/− mice display variable ‘open-field’ behaviors, impaired motor functions on the ‘rotating rod’, and dystonic ‘hind-limb clasping’. In this study, we report that these aberrant motor deficits displayed by Spr −/− mice were ameliorated by the therapeutic tyrosine diet for 10 days. This study also suggests that dopamine deficiency in brains of Spr −/− mice may not be the biological feature of aberrant motor behaviors associated with BH4 deficiency. Brain levels of dopamine (DA) and its metabolites in Spr −/− mice were not substantially increased by the dietary tyrosine therapy. However, we found that mTORC1 activity severely suppressed in brains of Spr −/− mice fed a normal diet was restored 10 days after feeding the mice the tyrosine diet. The present study proposes that brain mTORC1 signaling pathway is one of the potential targets in understanding abnormal motor behaviors associated with BH4-deficiency. PMID:23577163

  13. Nodal aberration theory applied to freeform surfaces

    NASA Astrophysics Data System (ADS)

    Fuerschbach, Kyle; Rolland, Jannick P.; Thompson, Kevin P.

    2014-12-01

    When new three-dimensional packages are developed for imaging optical systems, the rotational symmetry of the optical system is often broken, changing its imaging behavior and making the optical performance worse. A method to restore the performance is to use freeform optical surfaces that compensate directly the aberrations introduced from tilting and decentering the optical surfaces. In order to effectively optimize the shape of a freeform surface to restore optical functionality, it is helpful to understand the aberration effect the surface may induce. Using nodal aberration theory the aberration fields induced by a freeform surface in an optical system are explored. These theoretical predications are experimentally validated with the design and implementation of an aberration generating telescope.

  14. Aberrant meiotic behavior in Agave tequilana Weber var. azul

    PubMed Central

    Ruvalcaba-Ruiz, Domingo; Rodríguez-Garay, Benjamin

    2002-01-01

    Background Agave tequilana Weber var. azul, is the only one variety permitted by federal law in México to be used for tequila production which is the most popular contemporary alcoholic beverage made from agave and recognized worldwide. Despite the economic, genetic, and ornamental value of the plant, it has not been subjected to detailed cytogenetic research, which could lead to a better understanding of its reproduction for future genetic improvement. The objective of this work was to study the meiotic behavior in pollen mother cells and its implications on the pollen viability in Agave tequilana Weber var. azul. Results The analysis of Pollen Mother Cells in anaphase I (A-I) showed 82.56% of cells with a normal anaphase and, 17.44% with an irregular anaphase. In which 5.28% corresponded to cells with side arm bridges (SAB); 3.68% cells with one bridge and one fragment; 2.58% of irregular anaphase showed cells with one or two lagging chromosomes and 2.95% showed one acentric fragment; cells with two bridges and cells with two bridges and one acentric fragment were observed in frequencies of 1.60% and 1.35% respectively. In anaphase II some cells showed bridges and fragments too. Aberrant A-I cells had many shrunken or empty pollen grains (42.00%) and 58.00 % viable pollen. Conclusion The observed meiotic irregularities suggest that structural chromosome aberrations have occurred, such as heterozygous inversions, sister chromatid exchanges, deletions and duplications which in turn are reflected in a low pollen viability. PMID:12396234

  15. Aberrant meiotic behavior in Agave tequilana Weber var. azul.

    PubMed

    Ruvalcaba-Ruiz, Domingo; Rodríguez-Garay, Benjamin

    2002-10-23

    Agave tequilana Weber var. azul, is the only one variety permitted by federal law in México to be used for tequila production which is the most popular contemporary alcoholic beverage made from agave and recognized worldwide. Despite the economic, genetic, and ornamental value of the plant, it has not been subjected to detailed cytogenetic research, which could lead to a better understanding of its reproduction for future genetic improvement. The objective of this work was to study the meiotic behavior in pollen mother cells and its implications on the pollen viability in Agave tequilana Weber var. azul. The analysis of Pollen Mother Cells in anaphase I (A-I) showed 82.56% of cells with a normal anaphase and, 17.44% with an irregular anaphase. In which 5.28% corresponded to cells with side arm bridges (SAB); 3.68% cells with one bridge and one fragment; 2.58% of irregular anaphase showed cells with one or two lagging chromosomes and 2.95% showed one acentric fragment; cells with two bridges and cells with two bridges and one acentric fragment were observed in frequencies of 1.60% and 1.35% respectively. In anaphase II some cells showed bridges and fragments too. Aberrant A-I cells had many shrunken or empty pollen grains (42.00%) and 58.00 % viable pollen. The observed meiotic irregularities suggest that structural chromosome aberrations have occurred, such as heterozygous inversions, sister chromatid exchanges, deletions and duplications which in turn are reflected in a low pollen viability.

  16. Transgenerational effects of environmental enrichment on repetitive motor behavior development.

    PubMed

    Bechard, Allison R; Lewis, Mark H

    2016-07-01

    The favorable consequences of environmental enrichment (EE) on brain and behavior development are well documented. Much less is known, however, about transgenerational benefits of EE on non-enriched offspring. We explored whether transgenerational effects of EE might extend to the development of repetitive motor behaviors in deer mice. Repetitive motor behaviors are invariant patterns of movement that, across species, can be reduced by EE. We found that EE not only attenuated the development of repetitive behavior in dams, but also in their non-enriched offspring. Moreover, maternal behavior did not seem to mediate the transgenerational effect we found, although repetitive behavior was affected by reproductive experience. These data support a beneficial transgenerational effect of EE on repetitive behavior development and suggest a novel benefit of reproductive experience. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Neuromodulation during motor development and behavior.

    PubMed

    Pflüger, H J

    1999-12-01

    Important recent advances have been made in understanding the role of aminergic modulation during the maturation of Xenopus larvae swimming rhythms, including effects on particular ion channel types of component neurons, and the role of peptidergic modulation during development of adult central patterns generators in the stomatogastric ganglion of crustaceans. By recording from octopaminergic neuromodulatory neurons during ongoing motor behavior in the locust, new insights into the role of this peripheral neuromodulatory mechanism have been gained. In particular, it is now clear that the octopaminergic neuromodulatory system is automatically activated in parallel to the motor systems, and that both excitation and inhibition play important functional roles.

  18. Telephone Administration of the Aberrant Behavior Checklist: A Pilot Study of Feasibility in Children with Intellectual Disability and Autism

    ERIC Educational Resources Information Center

    Siegel, Matthew; Milligan, Briana; Stein, Hannah; Teer, Olivia; Smith, Kahsi A.

    2013-01-01

    To advance clinical care and research in children with intellectual disability and autism there is a growing need for efficient means to measure behavioral severity and response to treatment. The objective of this study was to assess the feasibility of telephone administration of the Aberrant Behavior Checklist-Irritability Subscale (ABC-I). The…

  19. A θ-γ oscillation code for neuronal coordination during motor behavior.

    PubMed

    Igarashi, Jun; Isomura, Yoshikazu; Arai, Kensuke; Harukuni, Rie; Fukai, Tomoki

    2013-11-20

    Sequential motor behavior requires a progression of discrete preparation and execution states. However, the organization of state-dependent activity in neuronal ensembles of motor cortex is poorly understood. Here, we recorded neuronal spiking and local field potential activity from rat motor cortex during reward-motivated movement and observed robust behavioral state-dependent coordination between neuronal spiking, γ oscillations, and θ oscillations. Slow and fast γ oscillations appeared during distinct movement states and entrained neuronal firing. γ oscillations, in turn, were coupled to θ oscillations, and neurons encoding different behavioral states fired at distinct phases of θ in a highly layer-dependent manner. These findings indicate that θ and nested dual band γ oscillations serve as the temporal structure for the selection of a conserved set of functional channels in motor cortical layer activity during animal movement. Furthermore, these results also suggest that cross-frequency couplings between oscillatory neuronal ensemble activities are part of the general coding mechanism in cortex.

  20. Using motor behavior during an early critical period to restore skilled limb movement after damage to the corticospinal motor system during development

    PubMed Central

    Friel, KM; Chakrabarty, S; H-C, Kuo; Martin, JH

    2012-01-01

    This study investigated requirements for restoring motor function after corticospinal (CS) system damage during early postnatal development. Activity-dependent competition between the CS tracts (CST) of the two hemispheres is imperative for normal development. Blocking primary motor cortex (M1) activity unilaterally during a critical period (postnatal weeks-PW-5–7) produces permanent contralateral motor skill impairments, loss of M1 motor map, aberrant CS terminations, and decreases in CST presynaptic sites and spinal cholinergic interneuron numbers. To repair these motor systems impairments and restore function, we manipulated motor experience in three groups of cats after this CST injury produced by inactivation. One group wore a jacket restraining the limb ipsilateral to inactivation, forcing use of the contralateral, impaired, limb, for the month following M1 inactivation (PW8–13; “Restraint Alone”). A second group wore the restraint during PW8–13, and was also trained for 1 h/day in a reaching task with the contralateral forelimb (“Early Training”). To test the efficacy of intervention during adolescence, a third group wore the restraint and received reach training during PW20–24 (“Delayed Training”). Early training restored CST connections and the M1 motor map; increased cholinergic spinal interneurons numbers on the contralateral, relative to ipsilateral, side; and abrogated limb control impairments. Delayed training restored CST connectivity and the M1 motor map, but not contralateral spinal cholinergic cell counts or motor performance. Restraint alone only restored CST connectivity. Our findings stress the need to reestablish the integrated functions of the CS system at multiple hierarchical levels in restoring skilled motor function after developmental injury. PMID:22764234

  1. Transformation of Context-dependent Sensory Dynamics into Motor Behavior

    PubMed Central

    Latorre, Roberto; Levi, Rafael; Varona, Pablo

    2013-01-01

    The intrinsic dynamics of sensory networks play an important role in the sensory-motor transformation. In this paper we use conductance based models and electrophysiological recordings to address the study of the dual role of a sensory network to organize two behavioral context-dependent motor programs in the mollusk Clione limacina. We show that: (i) a winner take-all dynamics in the gravimetric sensory network model drives the typical repetitive rhythm in the wing central pattern generator (CPG) during routine swimming; (ii) the winnerless competition dynamics of the same sensory network organizes the irregular pattern observed in the wing CPG during hunting behavior. Our model also shows that although the timing of the activity is irregular, the sequence of the switching among the sensory cells is preserved whenever the same set of neurons are activated in a given time window. These activation phase locks in the sensory signals are transformed into specific events in the motor activity. The activation phase locks can play an important role in motor coordination driven by the intrinsic dynamics of a multifunctional sensory organ. PMID:23459114

  2. Adult-onset stereotypical motor behaviors.

    PubMed

    Maltête, D

    Stereotypies have been defined as non-goal-directed movement patterns repeated continuously for a period of time in the same form and on multiple occasions, and which are typically distractible. Stereotypical motor behaviors are a common clinical feature of a variety of neurological conditions that affect cortical and subcortical functions, including autism, tardive dyskinesia, excessive dopaminergic treatment of Parkinson's disease and frontotemporal dementia. The main differential diagnosis of stereotypies includes tic disorders, motor mannerisms, compulsion and habit. The pathophysiology of stereotypies may involve the corticostriatal pathways, especially the orbitofrontal and anterior cingulated cortices. Because antipsychotics have long been used to manage stereotypical behaviours in mental retardation, stereotypies that present in isolation tend not to warrant pharmacological intervention, as the benefit-to-risk ratio is not great enough. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  3. Dopamine-Dependent Compensation Maintains Motor Behavior in Mice with Developmental Ablation of Dopaminergic Neurons

    PubMed Central

    DeMaro, Joseph A.; Knoten, Amanda; Hoshi, Masato; Pehek, Elizabeth; Johnson, Eugene M.; Gereau, Robert W.

    2013-01-01

    The loss of dopaminergic neurons in the substantia nigra pars compacta (SNc) and consequent depletion of striatal dopamine are known to underlie the motor deficits observed in Parkinson's disease (PD). Adaptive changes in dopaminergic terminals and in postsynaptic striatal neurons can compensate for significant losses of striatal dopamine, resulting in preservation of motor behavior. In addition, compensatory changes independent of striatal dopamine have been proposed based on PD therapies that modulate nondopaminergic circuits within the basal ganglia. We used a genetic strategy to selectively destroy dopaminergic neurons in mice during development to determine the necessity of these neurons for the maintenance of normal motor behavior in adult and aged mice. We find that loss of 90% of SNc dopaminergic neurons and consequent depletion of >95% of striatal dopamine does not result in changes in motor behavior in young-adult or aged mice as evaluated by an extensive array of motor behavior tests. Treatment of aged mutant mice with the dopamine receptor antagonist haloperidol precipitated motor behavior deficits in aged mutant mice, indicating that <5% of striatal dopamine is sufficient to maintain motor function in these mice. We also found that mutant mice exhibit an exaggerated response to l-DOPA compared with control mice, suggesting that preservation of motor function involves sensitization of striatal dopamine receptors. Our results indicate that congenital loss of dopaminergic neurons induces remarkable adaptions in the nigrostriatal system where limited amounts of dopamine in the dorsal striatum can maintain normal motor function. PMID:24155314

  4. Further characterization of repetitive behavior in C58 mice: developmental trajectory and effects of environmental enrichment.

    PubMed

    Muehlmann, A M; Edington, G; Mihalik, A C; Buchwald, Z; Koppuzha, D; Korah, M; Lewis, M H

    2012-12-01

    Aberrant repetitive behaviors are commonly observed in a variety of neurodevelopmental, neurological, and neuropsychiatric disorders. Little is known about the specific neurobiological mechanisms that underlie such behaviors, however, and effective treatments are lacking. Valid animal models can aid substantially in identifying pathophysiological factors mediating aberrant repetitive behavior and aid in treatment development. The C58 inbred mouse strain is a particularly promising model, and we have further characterized its repetitive behavior phenotype. Compared to C57BL/6 mice, C58 mice exhibit high rates of spontaneous hindlimb jumping and backward somersaulting reaching adult frequencies by 5 weeks post-weaning and adult temporal organization by 2 weeks post-weaning. The development of repetitive behavior in C58 mice was markedly attenuated by rearing these mice in larger, more complex environments. In addition to characterizing repetitive motor behavior, we also assessed related forms of inflexible behavior that reflect restricted and perseverative responding. Contrary to our hypothesis, C58 mice did not exhibit increased marble burying nor did they display reduced exploratory behavior in the holeboard task. The C58 strain appears to be a very useful model for the repetitive motor behavior characteristic of a number of clinical disorders. As an inbred mouse strain, studies using the C58 model can take full advantage of the tool kit of modern genetics and molecular neuroscience. This technical advantage makes the model a compelling choice for use in studies designed to elucidate the etiology and pathophysiology of aberrant repetitive behavior. Such findings should, in turn, translate into effective new treatments. Published by Elsevier B.V.

  5. Cerebellum in Levodopa-Induced Dyskinesias: The Unusual Suspect in the Motor Network

    PubMed Central

    Kishore, Asha; Popa, Traian

    2014-01-01

    information from the environment during motor performance. We propose that in dyskinesias, M1 neurons have lost the ability to depotentiate an activated synapse when exposed to acute pulsatile, non-physiological, dopaminergic surges and become abnormally receptive to unfiltered, aberrant, and non-salient afferent inputs from the environment. The motor program selection in response to such non-salient and behaviorally irrelevant afferent inputs would be abnormal and involuntary. The motor responses are worsened by the lack of normal subcortico–cortical inputs from cerebellum and basal ganglia, because of the aberrant plasticity at their own synapses. Artificial cerebellar stimulation might help re-establish the cerebellar and basal ganglia control over the non-salient inputs to the motor areas during synaptic dopaminergic surges. PMID:25183959

  6. Psychometric Study of the Aberrant Behavior Checklist in Fragile X Syndrome and Implications for Targeted Treatment

    ERIC Educational Resources Information Center

    Sansone, Stephanie M.; Widaman, Keith F.; Hall, Scott S.; Reiss, Allan L.; Lightbody, Amy; Kaufmann, Walter E.; Berry-Kravis, Elizabeth; Lachiewicz, Ave; Brown, Elaine C.; Hessl, David

    2012-01-01

    Animal studies elucidating the neurobiology of fragile X syndrome (FXS) have led to multiple controlled trials in humans, with the Aberrant Behavior Checklist-Community (ABC-C) commonly adopted as a primary outcome measure. A multi-site collaboration examined the psychometric properties of the ABC-C in 630 individuals (ages 3-25) with FXS using…

  7. Trained, Generalized, and Collateral Behavior Changes of Preschool Children Receiving Gross-Motor Skills Training.

    ERIC Educational Resources Information Center

    Kirby, Kimberly C.; Holborn, Stephen W.

    1986-01-01

    Three preschool children participated in a behavioral training program to improve their gross-motor skills. Results indicated that the program improved the 10 targeted gross-motor skills and that improvements sometimes generalized to other settings. The program did not produce changes in fine-motor skills or social behaviors. Implications are…

  8. Development of oral motor behavior related to the skill assisted spoon feeding.

    PubMed

    van den Engel-Hoek, Lenie; van Hulst, Karen C M; van Gerven, Marjo H J C; van Haaften, Leenke; de Groot, Sandra A F

    2014-05-01

    Milestones in the typical development of eating skills are considered to be nippling (breast or bottle), eating from a spoon, drinking from a cup, biting and chewing. The purpose of this research was to study the development and consolidation of oral motor behavior related to the skill assisted spoon feeding in young infants. The present study longitudinally investigated the development of this skill in 39 healthy children from the start of spoon feeding until the skill was acquired. The Observation List Spoon Feeding with 7 observation items for oral motor behavior and 6 items for abnormal behavior was used. Results showed that infants between 4 and 8 months of age needed 5.7 weeks (SD 2.1), with a range of 8 weeks (from 2 to 10 weeks) to acquire this skill. No significant correlation (p=.109) between age at start spoon feeding and weeks needed to develop the skill was found. During this period oral motor behavior consolidated and abnormal behavior diminished. With this study it is shown that the period in weeks needed to acquire the oral motor behavior for the skill assisted spoon feeding is important in case of feeding problems. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Validity and reliability of the Behavior Problems Inventory, the Aberrant Behavior Checklist, and the Repetitive Behavior Scale-Revised among infants and toddlers at risk for intellectual or developmental disabilities: a multi-method assessment approach.

    PubMed

    Rojahn, Johannes; Schroeder, Stephen R; Mayo-Ortega, Liliana; Oyama-Ganiko, Rosao; LeBlanc, Judith; Marquis, Janet; Berke, Elizabeth

    2013-05-01

    Reliable and valid assessment of aberrant behaviors is essential in empirically verifying prevention and intervention for individuals with intellectual or developmental disabilities (IDD). Few instruments exist which assess behavior problems in infants. The current longitudinal study examined the performance of three behavior-rating scales for individuals with IDD that have been proven psychometrically sound in older populations: the Aberrant Behavior Checklist (ABC), the Behavior Problems Inventory (BPI-01), and the Repetitive Behavior Scale - Revised (RBS-R). Data were analyzed for 180 between six and 36 months old children at risk for IDD. Internal consistency (Cronbach's α) across the subscales of the three instruments was variable. Test-retest reliability of the three BPI-01 subscales ranged from .68 to .77 for frequency ratings and from .65 to .80 for severity ratings (intraclass correlation coefficients). Using a multitrait-multimethod matrix approach high levels of convergent and discriminant validity across the three instruments was found. As anticipated, there was considerable overlap in the information produced by the three instruments; however, each behavior-rating instrument also contributed unique information. Our findings support using all three scales in conjunction if possible. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Video analysis of motor events in REM sleep behavior disorder.

    PubMed

    Frauscher, Birgit; Gschliesser, Viola; Brandauer, Elisabeth; Ulmer, Hanno; Peralta, Cecilia M; Müller, Jörg; Poewe, Werner; Högl, Birgit

    2007-07-30

    In REM sleep behavior disorder (RBD), several studies focused on electromyographic characterization of motor activity, whereas video analysis has remained more general. The aim of this study was to undertake a detailed and systematic video analysis. Nine polysomnographic records from 5 Parkinson patients with RBD were analyzed and compared with sex- and age-matched controls. Each motor event in the video during REM sleep was classified according to duration, type of movement, and topographical distribution. In RBD, a mean of 54 +/- 23.2 events/10 minutes of REM sleep (total 1392) were identified and visually analyzed. Seventy-five percent of all motor events lasted <2 seconds. Of these events, 1,155 (83.0%) were classified as elementary, 188 (13.5%) as complex behaviors, 50 (3.6%) as violent, and 146 (10.5%) as vocalizations. In the control group, 3.6 +/- 2.3 events/10 minutes (total 264) of predominantly elementary simple character (n = 240, 90.9%) were identified. Number and types of motor events differed significantly between patients and controls (P < 0.05). This study shows a very high number and great variety of motor events during REM sleep in symptomatic RBD. However, most motor events are minor, and violent episodes represent only a small fraction. Copyright 2007 Movement Disorder Society

  11. Aberrant learning in Parkinson's disease: A neurocomputational study on bradykinesia.

    PubMed

    Ursino, Mauro; Baston, Chiara

    2018-05-22

    Parkinson's disease (PD) is a neurodegenerative disorder characterized by a progressive decline in motor functions, such as bradykinesia, caused by the pathological denervation of nigrostriatal dopaminergic neurons within the basal ganglia (BG). It is acknowledged that dopamine (DA) directly affects the modulatory role of BG towards the cortex. However, a growing body of literature is suggesting that DA-induced aberrant synaptic plasticity could play a role in the core symptoms of PD, thus recalling for a "reconceptualization" of the pathophysiology. The aim of this work was to investigate DA-driven aberrant learning as a concurrent cause of bradykinesia, using a comprehensive, biologically inspired neurocomputational model of action selection in the BG. The model includes the three main pathways operating in the BG circuitry, that is the direct, indirect and hyperdirect pathways, and use a two-term Hebb rule to train synapses in the striatum, based on previous history of rewards and punishments. Levodopa pharmacodynamics is also incorporated. Through model simulations of the Alternate Finger Tapping motor task, we assessed the role of aberrant learning on bradykinesia. The results show that training under drug medication (levodopa) provides not only immediate but also delayed benefit lasting in time. Conversely, if performed in conditions of vanishing levodopa efficacy, training may result in dysfunctional corticostriatal synaptic plasticity, further worsening motor performances in PD subjects. This suggests that bradykinesia may result from the concurrent effects of low DA levels and dysfunctional plasticity and that training can be exploited in medicated subjects to improve levodopa treatment. © 2018 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  12. Influence of coma aberration on aperture averaged scintillations in oceanic turbulence

    NASA Astrophysics Data System (ADS)

    Luo, Yujuan; Ji, Xiaoling; Yu, Hong

    2018-01-01

    The influence of coma aberration on aperture averaged scintillations in oceanic turbulence is studied in detail by using the numerical simulation method. In general, in weak oceanic turbulence, the aperture averaged scintillation can be effectively suppressed by means of the coma aberration, and the aperture averaged scintillation decreases as the coma aberration coefficient increases. However, in moderate and strong oceanic turbulence the influence of coma aberration on aperture averaged scintillations can be ignored. In addition, the aperture averaged scintillation dominated by salinity-induced turbulence is larger than that dominated by temperature-induced turbulence. In particular, it is shown that for coma-aberrated Gaussian beams, the behavior of aperture averaged scintillation index is quite different from the behavior of point scintillation index, and the aperture averaged scintillation index is more suitable for characterizing scintillations in practice.

  13. Neonatal Stroke Causes Poor Midline Motor Behaviors and Poor Fine and Gross Motor Skills during Early Infancy

    ERIC Educational Resources Information Center

    Chen, Chao-Ying; Lo, Warren D.; Heathcock, Jill C.

    2013-01-01

    Upper extremity movements, midline behaviors, fine, and gross motor skills are frequently impaired in hemiparesis and cerebral palsy. We investigated midline toy exploration and fine and gross motor skills in infants at risk for hemiplegic cerebral palsy. Eight infants with neonatal stroke (NS) and thirteen infants with typical development (TD)…

  14. Differentiated Effects of Sensory Activities as Abolishing Operations via Non-Contingent Reinforcement on Academic and Aberrant Behavior

    ERIC Educational Resources Information Center

    Mancil, G. Richmond; Haydon, Todd; Boman, Marty

    2016-01-01

    The purpose of the study was to evaluate the effectiveness of sensory activities used as antecedent interventions on the percentage correct on academic tasks and rate of aberrant behavior in three elementary aged children with Autism Spectrum Disorders (ASD). Study activities were conducted in an after school program for children with ASD where…

  15. Does Speech Emerge from Earlier Appearing Oral Motor Behaviors?.

    ERIC Educational Resources Information Center

    Moore, Christopher A.; Ruark, Jacki L.

    1996-01-01

    This study of the oral motor behaviors of seven toddlers (age 15 months) may be interpreted to indicate that: (1) mandibular coordination follows a developmental continuum from earlier emerging behaviors, such as chewing and sucking, through babbling, to speech, or (2) unique task demands give rise to distinct mandibular coordinative constraints…

  16. Nodal aberration theory for wild-filed asymmetric optical systems

    NASA Astrophysics Data System (ADS)

    Chen, Yang; Cheng, Xuemin; Hao, Qun

    2016-10-01

    Nodal Aberration Theory (NAT) was used to calculate the zero field position in Full Field Display (FFD) for the given aberration term. Aiming at wide-filed non-rotational symmetric decentered optical systems, we have presented the nodal geography behavior of the family of third-order and fifth-order aberrations. Meanwhile, we have calculated the wavefront aberration expressions when one optical element in the system is tilted, which was not at the entrance pupil. By using a three-piece-cellphone lens example in optical design software CodeV, the nodal geography is testified under several situations; and the wavefront aberrations are calculated when the optical element is tilted. The properties of the nodal aberrations are analyzed by using Fringe Zernike coefficients, which are directly related with the wavefront aberration terms and usually obtained by real ray trace and wavefront surface fitting.

  17. The Effects of Sensory Manipulations on Motor Behavior: From Basic Science to Clinical Rehabilitation.

    PubMed

    Sugiyama, Taisei; Liew, Sook-Lei

    2017-01-01

    Modifying sensory aspects of the learning environment can influence motor behavior. Although the effects of sensory manipulations on motor behavior have been widely studied, there still remains a great deal of variability across the field in terms of how sensory information has been manipulated or applied. Here, the authors briefly review and integrate the literature from each sensory modality to gain a better understanding of how sensory manipulations can best be used to enhance motor behavior. Then, they discuss 2 emerging themes from this literature that are important for translating sensory manipulation research into effective interventions. Finally, the authors provide future research directions that may lead to enhanced efficacy of sensory manipulations for motor learning and rehabilitation.

  18. The development of behavioral abnormalities in the motor neuron degeneration (mnd) mouse.

    PubMed

    Bolivar, Valerie J; Scott Ganus, J; Messer, Anne

    2002-05-24

    The motor neuron degeneration (mnd) mouse, which has widespread abnormal accumulating lipoprotein and neuronal degeneration, has a mutation in CLN8, the gene for human progressive epilepsy with mental retardation (EPMR). EPMR is one of the neuronal ceroid lipofuscinoses (NCLs), a group of neurological disorders characterized by autofluorescent lipopigment accumulation, blindness, seizures, motor deterioration, and dementia. The human phenotype of EPMR suggests that, in addition to the motor symptoms previously categorized, various types of progressive behavioral abnormalities would be expected in mnd mice. We have therefore examined exploratory behavior, fear conditioning, and aggression in 2-3 month and 4-5 month old male mnd mice and age-matched C57BL/6 (B6) controls. The mnd mice displayed increased activity with decreased habituation in the activity monitor, poor contextual and cued memory, and heightened aggression relative to B6 controls. These behavioral deficits were most prominent at 4-5 months of age, which is prior to the onset of gross motor symptoms at 6 months. Our results provide a link from the mutation via pathology to a quantifiable multidimensional behavioral phenotype of this naturally occurring mouse model of NCL.

  19. Physiological markers of motor inhibition during human behavior

    PubMed Central

    Duque, Julie; Greenhouse, Ian; Labruna, Ludovica; Ivry, Richard B.

    2017-01-01

    Transcranial magnetic stimulation (TMS) studies in humans have shown that many behaviors engage processes that suppress excitability within the corticospinal tract. Inhibition of the motor output pathway has been extensively studied in the context of action stopping, where a planned movement needs to be abruptly aborted. Recent TMS work has also revealed markers of motor inhibition during the preparation of movement. Here, we review the evidence for motor inhibition during action stopping and action preparation, focusing on studies that have used TMS to monitor changes in the excitability of the corticospinal pathway. We discuss how these physiological results have motivated theoretical models of how the brain selects actions, regulates movement initiation and execution, and switches from one state to another. PMID:28341235

  20. The relationship between the behavior problems and motor skills of students with intellectual disability.

    PubMed

    Lee, Yangchool; Jeoung, Bogja

    2016-12-01

    The purpose of this study was to determine the relationship between the motor skills and the behavior problems of students with intellectual disabilities. The study participants were 117 students with intellectual disabilities who were between 7 and 25 years old (male, n=79; female, n=38) and attending special education schools in South Korea. Motor skill abilities were assessed by using the second version of the Bruininks-Oseretsky test of motor proficiency, which includes subtests in fine motor control, manual coordination, body coordination, strength, and agility. Data were analyzed with SPSS IBM 21 by using correlation and regression analyses, and the significance level was set at P <0.05. The results showed that fine motor precision and integration had a statistically significant influence on aggressive behavior. Manual dexterity showed a statistically significant influence on somatic complaint and anxiety/depression, and bilateral coordination had a statistically significant influence on social problems, attention problem, and aggressive behavior. Our results showed that balance had a statistically significant influence on social problems and aggressive behavior, and speed and agility had a statistically significant influence on social problems and aggressive behavior. Upper limb coordination and strength had a statistically significant influence on social problems.

  1. BEHAVIORAL AND LEARNING DISABILITIES ASSOCIATED WITH COGNITIVE-MOTOR DYSFUNCTION. INTERIM REPORT.

    ERIC Educational Resources Information Center

    BRAUN, JEAN S.; RUBIN, ELI Z.

    THIS REPORT EXAMINES THE RELATIONSHIP BETWEEN BEHAVIORAL AND ACADEMIC DISABILITIES AND COGNITIVE-MOTOR DYSFUNCTION AS REVEALED BY DATA ON 400 ELEMENTARY SCHOOL CHILDREN. THE BEHAVIOR CHECKLIST WAS USED AS A BASIS FOR SAMPLE SELECTION. BEHAVIOR CLUSTERS REFLECTING BOTH ANTI-SOCIAL TENDENCIES AND UNASSERTIVE, WITHDRAWN BEHAVIOR WERE IDENTIFIED. A…

  2. Motor Behavior: From Telegraph Keys and Twins to Linear Slides and Stepping

    ERIC Educational Resources Information Center

    Thomas, Jerry R.

    2006-01-01

    Motor behavior is a significant area of scholarship with 64 Fellows from the American Academy of Kinesiology and Physical Education engaged in that work since 1930. This paper provides a brief overview of the history of research in motor development and motor control/learning, particularly noting the contributions to scholarship of Academy…

  3. MOVEMENT BEHAVIOR AND MOTOR LEARNING. SECOND EDITION.

    ERIC Educational Resources Information Center

    CRATTY, BRYANT J.

    TO BRING TOGETHER DATA RELEVANT TO THE UNDERSTANDING OF HUMAN MOVEMENT WITH PARTICULAR REFERENCE TO LEARNING, THE TEXT SURVEYS THE CONCERN OF SEVERAL DISCIPLINES WITH MOTOR BEHAVIOR AND LEARNING. WORDS AND DEFINITIONS ARE ESTABLISHED, AND THE EVOLUTION OF THE HUMAN ACTION SYSTEM IS DISCUSSED. A CONSIDERATION OF PERCEPTION TREATS THE PROCESS OF…

  4. Anxiety, attention problems, hyperactivity, and the Aberrant Behavior Checklist in fragile X syndrome.

    PubMed

    Wheeler, Anne; Raspa, Melissa; Bann, Carla; Bishop, Ellen; Hessl, David; Sacco, Pat; Bailey, Donald B

    2014-01-01

    Behavior problems are a common challenge for individuals with fragile X syndrome (FXS) and constitute the primary clinical outcome domain in trials testing new FXS medications. However, little is known about the relationship between caregiver-reported behavior problems and co-occurring conditions such as anxiety and attention problems. In this study, 350 caregivers, each with at least one son or daughter with full-mutation FXS, rated one of their children with FXS using the Aberrant Behavior Checklist-Community Version (ABC-C); the Anxiety subscale of the Anxiety, Depression, and Mood Scale; and the Attention/Hyperactivity Items from the Symptom Inventories. In addition to examining family consequences of these behaviors, this study also sought to replicate psychometric findings for the ABC-C in FXS, to provide greater confidence for its use in clinical trials with this population. Psychometric properties and baseline ratings of problem behavior were consistent with other recent studies, further establishing the profile of problem behavior in FXS. Cross-sectional analyses suggest that selected dimensions of problem behavior, anxiety, and hyperactivity are age related; thus, age should serve as an important control in any studies of problem behavior in FXS. Measures of anxiety, attention, and hyperactivity were highly associated with behavior problems, suggesting that these factors at least coincide with problem behavior. However, these problems generally did not add substantially to variance in caregiver burden predicted by elevated behavior problems. The results provide further evidence of the incidence of problem behaviors and co-occurring conditions in FXS and the impact of these behaviors on the family. © 2013 Wiley Periodicals, Inc.

  5. Response inhibition in motor conversion disorder.

    PubMed

    Voon, Valerie; Ekanayake, Vindhya; Wiggs, Edythe; Kranick, Sarah; Ameli, Rezvan; Harrison, Neil A; Hallett, Mark

    2013-05-01

    Conversion disorders (CDs) are unexplained neurological symptoms presumed to be related to a psychological issue. Studies focusing on conversion paralysis have suggested potential impairments in motor initiation or execution. Here we studied CD patients with aberrant or excessive motor movements and focused on motor response inhibition. We also assessed cognitive measures in multiple domains. We compared 30 CD patients and 30 age-, sex-, and education-matched healthy volunteers on a motor response inhibition task (go/no go), along with verbal motor response inhibition (color-word interference) and measures of attention, sustained attention, processing speed, language, memory, visuospatial processing, and executive function including planning and verbal fluency. CD patients had greater impairments in commission errors on the go/no go task (P < .001) compared with healthy volunteers, which remained significant after Bonferroni correction for multiple comparisons and after controlling for attention, sustained attention, depression, and anxiety. There were no significant differences in other cognitive measures. We highlight a specific deficit in motor response inhibition that may play a role in impaired inhibition of unwanted movement such as the excessive and aberrant movements seen in motor conversion. Patients with nonepileptic seizures, a different form of conversion disorder, are commonly reported to have lower IQ and multiple cognitive deficits. Our results point toward potential differences between conversion disorder subgroups. © 2013 Movement Disorder Society. Copyright © 2013 Movement Disorder Society.

  6. Theory of aberration fields for general optical systems with freeform surfaces.

    PubMed

    Fuerschbach, Kyle; Rolland, Jannick P; Thompson, Kevin P

    2014-11-03

    This paper utilizes the framework of nodal aberration theory to describe the aberration field behavior that emerges in optical systems with freeform optical surfaces, particularly φ-polynomial surfaces, including Zernike polynomial surfaces, that lie anywhere in the optical system. If the freeform surface is located at the stop or pupil, the net aberration contribution of the freeform surface is field constant. As the freeform optical surface is displaced longitudinally away from the stop or pupil of the optical system, the net aberration contribution becomes field dependent. It is demonstrated that there are no new aberration types when describing the aberration fields that arise with the introduction of freeform optical surfaces. Significantly it is shown that the aberration fields that emerge with the inclusion of freeform surfaces in an optical system are exactly those that have been described by nodal aberration theory for tilted and decentered optical systems. The key contribution here lies in establishing the field dependence and nodal behavior of each freeform term that is essential knowledge for effective application to optical system design. With this development, the nodes that are distributed throughout the field of view for each aberration type can be anticipated and targeted during optimization for the correction or control of the aberrations in an optical system with freeform surfaces. This work does not place any symmetry constraints on the optical system, which could be packaged in a fully three dimensional geometry, without fold mirrors.

  7. Structural centrosome aberrations promote non-cell-autonomous invasiveness.

    PubMed

    Ganier, Olivier; Schnerch, Dominik; Oertle, Philipp; Lim, Roderick Yh; Plodinec, Marija; Nigg, Erich A

    2018-05-02

    Centrosomes are the main microtubule-organizing centers of animal cells. Although centrosome aberrations are common in tumors, their consequences remain subject to debate. Here, we studied the impact of structural centrosome aberrations, induced by deregulated expression of ninein-like protein (NLP), on epithelial spheres grown in Matrigel matrices. We demonstrate that NLP-induced structural centrosome aberrations trigger the escape ("budding") of living cells from epithelia. Remarkably, all cells disseminating into the matrix were undergoing mitosis. This invasive behavior reflects a novel mechanism that depends on the acquisition of two distinct properties. First, NLP-induced centrosome aberrations trigger a re-organization of the cytoskeleton, which stabilizes microtubules and weakens E-cadherin junctions during mitosis. Second, atomic force microscopy reveals that cells harboring these centrosome aberrations display increased stiffness. As a consequence, mitotic cells are pushed out of mosaic epithelia, particularly if they lack centrosome aberrations. We conclude that centrosome aberrations can trigger cell dissemination through a novel, non-cell-autonomous mechanism, raising the prospect that centrosome aberrations contribute to the dissemination of metastatic cells harboring normal centrosomes. © 2018 The Authors. Published under the terms of the CC BY NC ND 4.0 license.

  8. Motor Behavior Activates Bergmann Glial Networks

    PubMed Central

    Nimmerjahn, Axel; Mukamel, Eran A.; Schnitzer, Mark J.

    2010-01-01

    SUMMARY Although it is firmly established neuronal activity is a prime determinant of animal behavior, relationships between astrocytic excitation and animal behavior have remained opaque. Cerebellar Bergmann glia are radial astrocytes that are implicated in motor behavior and exhibit Ca2+-excitation. However, Ca2+-excitation in these cells has not previously been studied in behaving animals. Using two-photon microscopy we found that Bergmann glia exhibit three forms of Ca2+-excitation in awake behaving mice. Two of these are ongoing within the cerebellar vermis. During locomotor performance concerted Ca2+-excitation arises in networks of at least hundreds of Bergmann glia extending across several hundred microns or more. Concerted Ca2+-excitation was abolished by anesthesia or blockade of either neural activity or glutamatergic transmission. Thus, large networks of Bergmann glia can be activated by specific animal behaviors and undergo excitation of sufficient magnitude to potentially initiate macroscopic changes in brain dynamics or blood flow. PMID:19447095

  9. Physiological Markers of Motor Inhibition during Human Behavior.

    PubMed

    Duque, Julie; Greenhouse, Ian; Labruna, Ludovica; Ivry, Richard B

    2017-04-01

    Transcranial magnetic stimulation (TMS) studies in humans have shown that many behaviors engage processes that suppress excitability within the corticospinal tract. Inhibition of the motor output pathway has been extensively studied in the context of action stopping, where a planned movement needs to be abruptly aborted. Recent TMS work has also revealed markers of motor inhibition during the preparation of movement. Here, we review the evidence for motor inhibition during action stopping and action preparation, focusing on studies that have used TMS to monitor changes in the excitability of the corticospinal pathway. We discuss how these physiological results have motivated theoretical models of how the brain selects actions, regulates movement initiation and execution, and switches from one state to another. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Detecting Aberrant Response Patterns in the Rasch Model. Rapport 87-3.

    ERIC Educational Resources Information Center

    Kogut, Jan

    In this paper, the detection of response patterns aberrant from the Rasch model is considered. For this purpose, a new person fit index, recently developed by I. W. Molenaar (1987) and an iterative estimation procedure are used in a simulation study of Rasch model data mixed with aberrant data. Three kinds of aberrant response behavior are…

  11. Natural descriptions of motor behavior: examples from E. coli and C. elegans.

    NASA Astrophysics Data System (ADS)

    Ryu, William

    2007-03-01

    E. coli has a natural behavioral variable - the direction of rotation of its flagellar rotorary motor. Monitoring this one-dimensional behavioral response in reaction to chemical perturbation has been instrumental in the understanding of how E. coli performs chemotaxis at the genetic, physiological, and computational level. Here we apply this experimental strategy to the study of bacterial thermotaxis - a sensory mode that is less well understood. We investigate bacterial thermosensation by studying the motor response of single cells subjected to impulses of heat produced by an IR laser. A simple temperature dependent modification to an existing chemotaxis model can explain the observed temperature response. Higher organisms may have a more complicated behavioral response due to the simple fact that their motions have more degrees of freedom. Here we provide a principled analysis of motor behavior of such an organism -- the roundworm C. elegans. Using tracking video-microscopy we capture a worm's image and extract the skeleton of the shape as a head-to-tail ordered collection of tangent angles sampled along the curve. Applying principal components analysis we show that the space of shapes is remarkably low dimensional, with four dimensions accounting for > 95% of the shape variance. We also show that these dimensions align with behaviorally relevant states. As an application of this analysis we study the thermal response of worms stimulated by laser heating. Our quantitative description of C. elegans movement should prove useful in a wide variety of contexts, from the linking of motor output with neural circuitry to the genetic basis of adaptive behavior.

  12. Odor-identity dependent motor programs underlie behavioral responses to odors

    PubMed Central

    Jung, Seung-Hye; Hueston, Catherine; Bhandawat, Vikas

    2015-01-01

    All animals use olfactory information to perform tasks essential to their survival. Odors typically activate multiple olfactory receptor neuron (ORN) classes and are therefore represented by the patterns of active ORNs. How the patterns of active ORN classes are decoded to drive behavior is under intense investigation. In this study, using Drosophila as a model system, we investigate the logic by which odors modulate locomotion. We designed a novel behavioral arena in which we could examine a fly’s locomotion under precisely controlled stimulus condition. In this arena, in response to similarly attractive odors, flies modulate their locomotion differently implying that odors have a more diverse effect on locomotion than was anticipated. Three features underlie odor-guided locomotion: First, in response to odors, flies modulate a surprisingly large number of motor parameters. Second, similarly attractive odors elicit changes in different motor programs. Third, different ORN classes modulate different subset of motor parameters. DOI: http://dx.doi.org/10.7554/eLife.11092.001 PMID:26439011

  13. Early communicative behaviors and their relationship to motor skills in extremely preterm infants.

    PubMed

    Benassi, Erika; Savini, Silvia; Iverson, Jana M; Guarini, Annalisa; Caselli, Maria Cristina; Alessandroni, Rosina; Faldella, Giacomo; Sansavini, Alessandra

    2016-01-01

    Despite the predictive value of early spontaneous communication for identifying risk for later language concerns, very little research has focused on these behaviors in extremely low-gestational-age infants (ELGA<28 weeks) or on their relationship with motor development. In this study, communicative behaviors (gestures, vocal utterances and their coordination) were evaluated during mother-infant play interactions in 20 ELGA infants and 20 full-term infants (FT) at 12 months (corrected age for ELGA infants). Relationships between gestures and motor skills, evaluated using the Bayley-III Scales were also examined. ELGA infants, compared with FT infants, showed less advanced communicative, motor, and cognitive skills. Giving and representational gestures were produced at a lower rate by ELGA infants. In addition, pointing gestures and words were produced by a lower percentage of ELGA infants. Significant positive correlations between gestures (pointing and representational gestures) and fine motor skills were found in the ELGA group. We discuss the relevance of examining spontaneous communicative behaviors and motor skills as potential indices of early development that may be useful for clinical assessment and intervention with ELGA infants. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. [Cognitive, linguistic, motoric, and social deficits in schoolstarters with behavioral disorders].

    PubMed

    Korsch, Franziska; Petermann, Ulrike; Schmidt, Sören; Petermann, Franz

    2013-01-01

    Studies show that ADHD, conduct disorders, and anxiety disorders are clinical disorders mostly diagnosed in schoolstarters. The preschool medical examination in Bremen was therefore extended by behavioral screenings. Based on their screening results from the SEU (health examination for school entry) 2011 in Bremen, 67 preschoolers were tested for behavioral disorders. Subsequently, children with behavioral or emotional symptoms (N = 56) were compared to symptomfree controls (N = 52) for their cognitive, motoric, linguistic, and social-emotional development. Psychosocial health was obtained through external assessment by the parents and kindergarten teachers. Results of the WPPSI-III, M-ABC-2, and ET 6-6 were included in the analysis. 32 children met the criteria for behavioral disorders. Children with behavioral or emotional symptoms showed significant lower scores on tests measuring cognitive, motoric, linguistic and emotional development compared to controls. Results suggest that there is necessity to screen all preschoolers for behavioral disorders before entering school. Because children with clinical or subclinical behavioral disorders showed major developmental deficits compared to children without behavioral symptoms, it is essential to conduct a multiple assessment on children with suspected behavioral disorders to ensure early developmental support and adequate interventional programs.

  15. Aberrant Behaviors and Road Accidents among Iranian Truck Drivers, 2010.

    PubMed

    Ketabi, Damon; Barkhordari, Abalfazl; Mirmohammadi, Seyyed Jalil; Mehrparvar, Amir Houshang

    2011-01-01

    Road accidents are a social phenomenon in different communities that its infra-structural dimensions of which as well as technologic failures such as road quality, and tech-nical faults of automobiles, need to be assessed in detail. Iran has the first order in the world for deadly road accidents. This study was designed to assess the association between aberrant behaviors of truck drivers and the incidence of road accidents in Yazd, center of Iran, in 2010. This cross-sectional descriptive-analytic study was conducted on 300 truck drivers in Yazd. We used 3 questionnaires, including one for demographic data, Driver Behavior Questionnaire (DBQ), and one for drivers' self-evaluation of the of their driving. Five types of the behavior had the highest frequency: Misjudge speed of oncoming vehicle when overtaking.; Deliberately disregard the speed limits late at night or very early in the morning.; Ignore 'give way' signs, and narrowly avoid colliding with traffic having right of way.; Stuck behind a slow-moving vehicle on a two-lane highway, you are driven by frustration to try to overtake in risky circumstances.; Drive with only 'half-an-eye' on the road while looking at a map, changing a cassette or radio channel, etc. The more the driver's driv-ing was influenced by emotional and mental states the more deliberate violations and slips. Among truck drivers, safety has not developed sufficiently, and because of the dangers of road accidents both for the drivers and other people and its economic losses, the importance of the presenting some solutions is completely obvious.

  16. Fast social-like learning of complex behaviors based on motor motifs.

    PubMed

    Calvo Tapia, Carlos; Tyukin, Ivan Y; Makarov, Valeri A

    2018-05-01

    Social learning is widely observed in many species. Less experienced agents copy successful behaviors exhibited by more experienced individuals. Nevertheless, the dynamical mechanisms behind this process remain largely unknown. Here we assume that a complex behavior can be decomposed into a sequence of n motor motifs. Then a neural network capable of activating motor motifs in a given sequence can drive an agent. To account for (n-1)! possible sequences of motifs in a neural network, we employ the winnerless competition approach. We then consider a teacher-learner situation: one agent exhibits a complex movement, while another one aims at mimicking the teacher's behavior. Despite the huge variety of possible motif sequences we show that the learner, equipped with the provided learning model, can rewire "on the fly" its synaptic couplings in no more than (n-1) learning cycles and converge exponentially to the durations of the teacher's motifs. We validate the learning model on mobile robots. Experimental results show that the learner is indeed capable of copying the teacher's behavior composed of six motor motifs in a few learning cycles. The reported mechanism of learning is general and can be used for replicating different functions, including, for example, sound patterns or speech.

  17. Fast social-like learning of complex behaviors based on motor motifs

    NASA Astrophysics Data System (ADS)

    Calvo Tapia, Carlos; Tyukin, Ivan Y.; Makarov, Valeri A.

    2018-05-01

    Social learning is widely observed in many species. Less experienced agents copy successful behaviors exhibited by more experienced individuals. Nevertheless, the dynamical mechanisms behind this process remain largely unknown. Here we assume that a complex behavior can be decomposed into a sequence of n motor motifs. Then a neural network capable of activating motor motifs in a given sequence can drive an agent. To account for (n -1 )! possible sequences of motifs in a neural network, we employ the winnerless competition approach. We then consider a teacher-learner situation: one agent exhibits a complex movement, while another one aims at mimicking the teacher's behavior. Despite the huge variety of possible motif sequences we show that the learner, equipped with the provided learning model, can rewire "on the fly" its synaptic couplings in no more than (n -1 ) learning cycles and converge exponentially to the durations of the teacher's motifs. We validate the learning model on mobile robots. Experimental results show that the learner is indeed capable of copying the teacher's behavior composed of six motor motifs in a few learning cycles. The reported mechanism of learning is general and can be used for replicating different functions, including, for example, sound patterns or speech.

  18. Phrenic Motor Unit Recruitment during Ventilatory and Non-Ventilatory Behaviors

    PubMed Central

    Mantilla, Carlos B.; Sieck, Gary C.

    2011-01-01

    Phrenic motoneurons are located in the cervical spinal cord and innervate the diaphragm muscle, the main inspiratory muscle in mammals. Similar to other skeletal muscles, phrenic motoneurons and diaphragm muscle fibers form motor units which are the final element of neuromotor control. In addition to their role in sustaining ventilation, phrenic motor units are active in other non-ventilatory behaviors important for airway clearance such as coughing or sneezing. Diaphragm muscle fibers comprise all fiber types and are commonly classified based on expression of contractile proteins including myosin heavy chain isoforms. Although there are differences in contractile and fatigue properties across motor units, there is a matching of properties for the motor neuron and muscle fibers within a motor unit. Motor units are generally recruited in order such that fatigue-resistant motor units are recruited earlier and more often than more fatigable motor units. Thus, in sustaining ventilation, fatigue-resistant motor units are likely required. Based on a series of studies in cats, hamsters and rats, an orderly model of motor unit recruitment was proposed that takes into consideration the maximum forces generated by single type-identified diaphragm muscle fibers as well as the proportion of the different motor unit types. Using this model, eupnea can be accomplished by activation of only slow-twitch diaphragm motor units and only a subset of fast-twitch, fatigue-resistant units. Activation of fast-twitch fatigable motor units only becomes necessary when accomplishing tasks that require greater force generation by the diaphragm muscle, e.g., sneezing and coughing. PMID:21763470

  19. Phrenic motor unit recruitment during ventilatory and non-ventilatory behaviors.

    PubMed

    Mantilla, Carlos B; Sieck, Gary C

    2011-10-15

    Phrenic motoneurons are located in the cervical spinal cord and innervate the diaphragm muscle, the main inspiratory muscle in mammals. Similar to other skeletal muscles, phrenic motoneurons and diaphragm muscle fibers form motor units which are the final element of neuromotor control. In addition to their role in sustaining ventilation, phrenic motor units are active in other non-ventilatory behaviors important for airway clearance such as coughing or sneezing. Diaphragm muscle fibers comprise all fiber types and are commonly classified based on expression of contractile proteins including myosin heavy chain isoforms. Although there are differences in contractile and fatigue properties across motor units, there is a matching of properties for the motor neuron and muscle fibers within a motor unit. Motor units are generally recruited in order such that fatigue-resistant motor units are recruited earlier and more often than more fatigable motor units. Thus, in sustaining ventilation, fatigue-resistant motor units are likely required. Based on a series of studies in cats, hamsters and rats, an orderly model of motor unit recruitment was proposed that takes into consideration the maximum forces generated by single type-identified diaphragm muscle fibers as well as the proportion of the different motor unit types. Using this model, eupnea can be accomplished by activation of only slow-twitch diaphragm motor units and only a subset of fast-twitch, fatigue-resistant units. Activation of fast-twitch fatigable motor units only becomes necessary when accomplishing tasks that require greater force generation by the diaphragm muscle, e.g., sneezing and coughing. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Sema4D/CD100 deficiency leads to superior performance in mouse motor behavior.

    PubMed

    Yukawa, Kazunori; Tanaka, Tetsuji; Takeuchi, Noriko; Iso, Hiroyuki; Li, Li; Kohsaka, Akira; Waki, Hidefumi; Miyajima, Masayasu; Maeda, Masanobu; Kikutani, Hitoshi; Kumanogoh, Atsushi

    2009-05-01

    Sema4D/CD100 is a type of class 4 semaphorin, exhibiting crucial roles in growth cone guidance in developing neurons. Sema4D is widely expressed throughout the central nervous system in embryonic mouse brain, and is selectively localized to oligodendrocytes and myelin in the postnatal brain. However, direct evidence of the actual involvement of Sema4D in the neuronal network development crucial for neurobehavioral performance is still lacking. The present study therefore examined whether Sema4D deficiency leads to abnormal behavioral development. Both wild-type and Sema4D-deficient mice were subjected to behavioral analyses including open-field, adhesive tape removal, rotarod tests and a water maze task. Open-field tests revealed increased locomotor activity in Sema4D-deficient mice with less percentage of time spent in the center of the field. In both the adhesive tape removal and rotarod tests, which examine motor coordination and balance, Sema4D-deficient mice showed significantly superior performance, suggesting facilitated motor behavior. Both Sema4D-deficient and wild-type mice successfully learnt the water maze task, locating a hidden escape platform, and also showed precise memory for the platform position in probe tests. However, the swimming speed of Sema4D-deficient mice was significantly faster than that of wild-type mice, providing further evidence of their accelerated motor behavior. Our mouse behavioral analyses revealed enhanced motor activity in Sema4D-deficient mice, suggesting the crucial involvement of Sema4D in the neurodevelopmental processes of the central structures mediating motor behavior in mice.

  1. What Behavioral and Psychological Symptoms of Dementia Affect Caregiver Burnout?

    PubMed

    Hiyoshi-Taniguchi, Kazuko; Becker, Carl B; Kinoshita, Ayae

    2018-01-01

    Patients' irritability and aggression have been linked to caregiver depression, but the behaviors that most burden caregivers are not yet definitively identified. This study examines the connection between behavioral and psychological symptoms of dementia (BPSD) and the burnout of caregivers caring for home-dwelling elders with dementia symptoms in Japan. 80 Japanese rural and urban family caregivers completed detailed questionnaires about their experiences in caring for demented family members. We statistically analyzed the results for correlations between types of dementia, Pines Burnout, and Caregiver Distress. BPSD symptom severity significantly correlated with caregiver distress. The dementia symptoms most strongly correlated with caregiver burnout were: aggression, irritability, abnormal motor behavior, and hallucinations. Among the commonest symptoms, apathy, anxiety, and depression did not seriously aggravate caregiver burnout. Caregivers displayed higher burnout facing agitation/aggression, irritability, aberrant motor behavior, and hallucinations. Caregivers' reported distress was surprisingly dissimilar to their burnout scores; patients' delusions and anxiety led to higher distress reporting but not to burnout. Advance diagnosis of BPSD symptoms should be helpful to support nurses and caregivers of dementia patients. Particular support should be considered for caregivers and nurses of patients expressing aggression, irritability, abnormal motor behavior, and hallucination.

  2. [Non-motor symptoms in Parkinson's disease: cognition and behavior].

    PubMed

    Bonnet, Anne Marie; Czernecki, Virginie

    2013-09-01

    Although the diagnosis of Parkinson disease is based on motor symptoms, it is now well known that non-motor symptoms are an integral part of this pathology, involving in fact multiple systems. These non-motor symptoms affect large population of patients and can appear sometimes before the motor disorders. The non-motor symptoms include mainly neuropsychological difficulties, neuropsychiatric symptoms, and autonomic disorders, but involve also pain and sleep disturbances for example. Depression may occur at any stage of the disease, and consists in major depressive disorder, minor depressive disorder, and dysthymia. During the course of the disease, 50% of patients experience anxiety. Apathy is present in up to 30-40% of patients, due to loss of motivation, appearing in emotional, intellectual and behavioral domains. Dopamine dysregulation syndrome and impulse control disorders are not rare, and in relation with dopaminergic therapies. Impulse control disorders include pathological gambling, hyper sexuality, compulsive shopping, and eating disorder. Visual hallucinations can occur in 30% of patients, mostly induced by dopaminergic therapies. Often, they have deeper impact on the quality of life than the motor symptoms themselves, which stay the focus of attention during consulting. Identifying those can help in providing better care with a positive impact on the quality of life of the patients.

  3. Effects of diet and behavior therapy on social and motor behavior of retarded phenylketonuric adults: an experimental analysis.

    PubMed

    Marholin, D; Pohl, R E; Stewart, R M; Touchette, P E; Townsend, N M; Kolodny, E H

    1978-03-01

    The effects of a low phenylalanine diet on six retarded phenylketonuric adults were assessed. An ABA individual-subject design was used in experiment I to assess the effects of a low phenylalanine diet on social and motor behavior. Following a baseline during which the subjects ingested a normal phenylalanine diet (phase A), a low phenylalanine diet (phase B) was administered in a double blind fashion. Finally, the baseline condition (phase A) was reinstated (normal diet). The low phenylalanine diet resulted in few significant behavioral changes for those subjects with which proper methodologic controls were employed. However, for two of six subjects motor behavior, including stereotypy and tremor, seem to have ameliorated. In experiment II, applied behavior analysis techniques, including differential reinforcement of other behavior and time out, were combined to radically reduce the frequency of stereotypy and self-abuse exhibited by one of the six subjects of experiment I.

  4. Associations of Gross Motor Delay, Behavior, and Quality of Life in Young Children With Autism Spectrum Disorder.

    PubMed

    Hedgecock, James B; Dannemiller, Lisa A; Shui, Amy M; Rapport, Mary Jane; Katz, Terry

    2018-04-01

    Young children with autism spectrum disorder (ASD) often have gross motor delays that may accentuate problem daytime behavior and health-related quality of life (QoL). The objective of this study was to describe the degree of gross motor delays in young children with ASD and associations of gross motor delays with problem daytime behavior and QoL. The primary hypothesis was that Gross motor delays significantly modifies the associations between internalizing or externalizing problem daytime behavior and QoL. This study used a cross-sectional, retrospective analysis. Data from 3253 children who were 2 to 6 years old and who had ASD were obtained from the Autism Speaks Autism Treatment Network and analyzed using unadjusted and adjusted linear regression. Measures included the Vineland Adaptive Behavior Scales, 2nd edition, gross motor v-scale score (VABS-GM) (for Gross motor delays), the Child Behavior Checklist (CBCL) (for Problem daytime behavior), and the Pediatric Quality of Life Inventory (PedsQL) (for QoL). The mean VABS-GM was 12.12 (SD = 2.2), representing performance at or below the 16th percentile. After adjustment for covariates, the internalizing CBCL t score decreased with increasing VABS-GM (β = - 0.64 SE = 0.12). Total and subscale PedsQL scores increased with increasing VABS-GM (for total score: β = 1.79 SE = 0.17; for subscale score: β = 0.9-2.66 SE = 0.17-0.25). CBCL internalizing and externalizing t scores decreased with increasing PedsQL total score (β = - 0.39 SE = 0.01; β = - 0.36 SE = 0.01). The associations between CBCL internalizing or externalizing t scores and PedsQL were significantly modified by VABSGM (β = - 0.026 SE = 0.005]; β = - 0.019 SE = 0.007). The study lacked ethnic and socioeconomic diversity. Measures were collected via parent report without accompanying clinical assessment. Cross motor delay was independently associated with Problem daytime behavior and QoL in children with ASD. Gross

  5. Behavioral evidence for left-hemisphere specialization of motor planning

    PubMed Central

    Meulenbroek, Ruud G. J.; Steenbergen, Bert

    2010-01-01

    Recent studies suggest that the left hemisphere is dominant for the planning of motor actions. This left-hemisphere specialization hypothesis was proposed in various lines of research, including patient studies, motor imagery studies, and studies involving neurophysiological techniques. However, most of these studies are primarily based on experiments involving right-hand-dominant participants. Here, we present the results of a behavioral study with left-hand-dominant participants, which follows up previous work in right-hand-dominant participants. In our experiment, participants grasped CD casings and replaced them in a different, pre-cued orientation. Task performance was measured by the end-state comfort effect, i.e., the anticipated degree of physical comfort associated with the posture that is planned to be adopted at movement completion. Both left- and right-handed participants showed stronger end-state comfort effects for their right hand compared to their left hand. These results lend behavioral support to the left-hemisphere-dominance motion-planning hypothesis. PMID:21184219

  6. Deprivation and Recovery of Sleep in Succession Enhances Reflexive Motor Behavior

    PubMed Central

    Sprenger, Andreas; Weber, Frederik D.; Machner, Bjoern; Talamo, Silke; Scheffelmeier, Sabine; Bethke, Judith; Helmchen, Christoph; Gais, Steffen; Kimmig, Hubert; Born, Jan

    2015-01-01

    Sleep deprivation impairs inhibitory control over reflexive behavior, and this impairment is commonly assumed to dissipate after recovery sleep. Contrary to this belief, here we show that fast reflexive behaviors, when practiced during sleep deprivation, is consolidated across recovery sleep and, thereby, becomes preserved. As a model for the study of sleep effects on prefrontal cortex-mediated inhibitory control in humans, we examined reflexive saccadic eye movements (express saccades), as well as speeded 2-choice finger motor responses. Different groups of subjects were trained on a standard prosaccade gap paradigm before periods of nocturnal sleep and sleep deprivation. Saccade performance was retested in the next morning and again 24 h later. The rate of express saccades was not affected by sleep after training, but slightly increased after sleep deprivation. Surprisingly, this increase augmented even further after recovery sleep and was still present 4 weeks later. Additional experiments revealed that the short testing after sleep deprivation was sufficient to increase express saccades across recovery sleep. An increase in speeded responses across recovery sleep was likewise found for finger motor responses. Our findings indicate that recovery sleep can consolidate motor disinhibition for behaviors practiced during prior sleep deprivation, thereby persistently enhancing response automatization. PMID:26048955

  7. Deprivation and Recovery of Sleep in Succession Enhances Reflexive Motor Behavior.

    PubMed

    Sprenger, Andreas; Weber, Frederik D; Machner, Bjoern; Talamo, Silke; Scheffelmeier, Sabine; Bethke, Judith; Helmchen, Christoph; Gais, Steffen; Kimmig, Hubert; Born, Jan

    2015-11-01

    Sleep deprivation impairs inhibitory control over reflexive behavior, and this impairment is commonly assumed to dissipate after recovery sleep. Contrary to this belief, here we show that fast reflexive behaviors, when practiced during sleep deprivation, is consolidated across recovery sleep and, thereby, becomes preserved. As a model for the study of sleep effects on prefrontal cortex-mediated inhibitory control in humans, we examined reflexive saccadic eye movements (express saccades), as well as speeded 2-choice finger motor responses. Different groups of subjects were trained on a standard prosaccade gap paradigm before periods of nocturnal sleep and sleep deprivation. Saccade performance was retested in the next morning and again 24 h later. The rate of express saccades was not affected by sleep after training, but slightly increased after sleep deprivation. Surprisingly, this increase augmented even further after recovery sleep and was still present 4 weeks later. Additional experiments revealed that the short testing after sleep deprivation was sufficient to increase express saccades across recovery sleep. An increase in speeded responses across recovery sleep was likewise found for finger motor responses. Our findings indicate that recovery sleep can consolidate motor disinhibition for behaviors practiced during prior sleep deprivation, thereby persistently enhancing response automatization. © The Author 2015. Published by Oxford University Press.

  8. Expression of ALS/FTD-linked mutant CCNF in zebrafish leads to increased cell death in the spinal cord and an aberrant motor phenotype.

    PubMed

    Hogan, Alison L; Don, Emily K; Rayner, Stephanie L; Lee, Albert; Laird, Angela S; Watchon, Maxinne; Winnick, Claire; Tarr, Ingrid S; Morsch, Marco; Fifita, Jennifer A; Gwee, Serene S L; Formella, Isabel; Hortle, Elinor; Yuan, Kristy C; Molloy, Mark P; Williams, Kelly L; Nicholson, Garth A; Chung, Roger S; Blair, Ian P; Cole, Nicholas J

    2017-07-15

    Amyotrophic lateral sclerosis (ALS) is a rapidly progressive, fatal neurodegenerative disease characterised by the death of upper and lower motor neurons. Approximately 10% of cases have a known family history of ALS and disease-linked mutations in multiple genes have been identified. ALS-linked mutations in CCNF were recently reported, however the pathogenic mechanisms associated with these mutations are yet to be established. To investigate possible disease mechanisms, we developed in vitro and in vivo models based on an ALS-linked missense mutation in CCNF. Proteomic analysis of the in vitro models identified the disruption of several cellular pathways in the mutant model, including caspase-3 mediated cell death. Transient overexpression of human CCNF in zebrafish embryos supported this finding, with fish expressing the mutant protein found to have increased levels of cleaved (activated) caspase-3 and increased cell death in the spinal cord. The mutant CCNF fish also developed a motor neuron axonopathy consisting of shortened primary motor axons and increased frequency of aberrant axonal branching. Importantly, we demonstrated a significant correlation between the severity of the CCNF-induced axonopathy and a reduced motor response to a light stimulus (photomotor response). This is the first report of an ALS-linked CCNF mutation in vivo and taken together with the in vitro model identifies the disruption of cell death pathways as a significant consequence of this mutation. Additionally, this study presents a valuable new tool for use in ongoing studies investigating the pathobiology of ALS-linked CCNF mutations. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Effect of Aging on Motor Inhibition during Action Preparation under Sensory Conflict.

    PubMed

    Duque, Julie; Petitjean, Charlotte; Swinnen, Stephan P

    2016-01-01

    Motor behaviors often require refraining from selecting options that may be part of the repertoire of natural response tendencies but that are in conflict with ongoing goals. The presence of sensory conflict has a behavioral cost but the latter can be attenuated in contexts where control processes are recruited because conflict is expected in advance, producing a behavioral gain compared to contexts where conflict occurs in a less predictable way. In the present study, we investigated the corticospinal correlates of these behavioral effects (both conflict-driven cost and context-related gain). To do so, we measured motor-evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) over the primary motor cortex (M1) of young and healthy older adults performing the Eriksen Flanker Task. Subjects performed button-presses according to a central arrow, flanked by irrelevant arrows pointing in the same (congruent trial) or opposite direction (incongruent trial). Conflict expectation was manipulated by changing the probability of congruent and incongruent trials in a given block. It was either high (mostly incongruent blocks, MIB, 80% incongruent trials) or low (mostly congruent blocks, MCB, 80% congruent). The MEP data indicate that the conflict-driven behavioral cost is associated with a strong increase in inappropriate motor activity regardless of the age of individuals, as revealed by larger MEPs in the non-responding muscle in incongruent than in congruent trials. However, this aberrant facilitation disappeared in both groups of subjects when conflict could be anticipated (i.e., in the MIBs) compared to when it occurred in a less predictably way (MCBs), probably allowing the behavioral gain observed in both the young and the older individuals. Hence, the ability to overcome and anticipate conflict was surprisingly preserved in the older adults. Nevertheless, some control processes are likely to evolve with age because the behavioral gain observed in

  10. Effect of Aging on Motor Inhibition during Action Preparation under Sensory Conflict

    PubMed Central

    Duque, Julie; Petitjean, Charlotte; Swinnen, Stephan P.

    2016-01-01

    Motor behaviors often require refraining from selecting options that may be part of the repertoire of natural response tendencies but that are in conflict with ongoing goals. The presence of sensory conflict has a behavioral cost but the latter can be attenuated in contexts where control processes are recruited because conflict is expected in advance, producing a behavioral gain compared to contexts where conflict occurs in a less predictable way. In the present study, we investigated the corticospinal correlates of these behavioral effects (both conflict-driven cost and context-related gain). To do so, we measured motor-evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) over the primary motor cortex (M1) of young and healthy older adults performing the Eriksen Flanker Task. Subjects performed button-presses according to a central arrow, flanked by irrelevant arrows pointing in the same (congruent trial) or opposite direction (incongruent trial). Conflict expectation was manipulated by changing the probability of congruent and incongruent trials in a given block. It was either high (mostly incongruent blocks, MIB, 80% incongruent trials) or low (mostly congruent blocks, MCB, 80% congruent). The MEP data indicate that the conflict-driven behavioral cost is associated with a strong increase in inappropriate motor activity regardless of the age of individuals, as revealed by larger MEPs in the non-responding muscle in incongruent than in congruent trials. However, this aberrant facilitation disappeared in both groups of subjects when conflict could be anticipated (i.e., in the MIBs) compared to when it occurred in a less predictably way (MCBs), probably allowing the behavioral gain observed in both the young and the older individuals. Hence, the ability to overcome and anticipate conflict was surprisingly preserved in the older adults. Nevertheless, some control processes are likely to evolve with age because the behavioral gain observed in

  11. Cellular mechanisms underlying behavioral state-dependent bidirectional modulation of motor cortex output.

    PubMed

    Schiemann, Julia; Puggioni, Paolo; Dacre, Joshua; Pelko, Miha; Domanski, Aleksander; van Rossum, Mark C W; Duguid, Ian

    2015-05-26

    Neuronal activity in primary motor cortex (M1) correlates with behavioral state, but the cellular mechanisms underpinning behavioral state-dependent modulation of M1 output remain largely unresolved. Here, we performed in vivo patch-clamp recordings from layer 5B (L5B) pyramidal neurons in awake mice during quiet wakefulness and self-paced, voluntary movement. We show that L5B output neurons display bidirectional (i.e., enhanced or suppressed) firing rate changes during movement, mediated via two opposing subthreshold mechanisms: (1) a global decrease in membrane potential variability that reduced L5B firing rates (L5Bsuppressed neurons), and (2) a coincident noradrenaline-mediated increase in excitatory drive to a subpopulation of L5B neurons (L5Benhanced neurons) that elevated firing rates. Blocking noradrenergic receptors in forelimb M1 abolished the bidirectional modulation of M1 output during movement and selectively impaired contralateral forelimb motor coordination. Together, our results provide a mechanism for how noradrenergic neuromodulation and network-driven input changes bidirectionally modulate M1 output during motor behavior. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  12. A Model for the Transfer of Perceptual-Motor Skill Learning in Human Behaviors

    ERIC Educational Resources Information Center

    Rosalie, Simon M.; Muller, Sean

    2012-01-01

    This paper presents a preliminary model that outlines the mechanisms underlying the transfer of perceptual-motor skill learning in sport and everyday tasks. Perceptual-motor behavior is motivated by performance demands and evolves over time to increase the probability of success through adaptation. Performance demands at the time of an event…

  13. Motor characteristics determine the rheological behavior of a suspension of microswimmers

    NASA Astrophysics Data System (ADS)

    Karmakar, Richa; Gulvady, Ranjit; Tirumkudulu, Mahesh S.; Venkatesh, K. V.

    2014-07-01

    A suspension of motile cells exhibits complex rheological properties due to their collective motion. We measure the shear viscosity of a suspension of Escherichia coli strains varying in motor characteristics such as duration of run and tumble. At low cell densities, all strains irrespective of their motor characteristics exhibit a linear increase in viscosity with cell density suggesting that the cells behave as a suspension of passive rods with an effective aspect ratio set by the motor characteristics of the bacteria. As the cell density is increased beyond a critical value, the viscosity drops sharply signaling the presence of strongly coordinated motion among bacteria. The critical density depends not only on the magnitude of shear but also the motor characteristics of individual cells. High shear rate disrupts the coordinated motion reducing its behavior, once again, to a suspension of inactive particles.

  14. Interindividual differences in motor network connectivity and behavioral response to iTBS in stroke patients.

    PubMed

    Diekhoff-Krebs, Svenja; Pool, Eva-Maria; Sarfeld, Anna-Sophia; Rehme, Anne K; Eickhoff, Simon B; Fink, Gereon R; Grefkes, Christian

    2017-01-01

    Cerebral plasticity-inducing approaches like repetitive transcranial magnetic stimulation (rTMS) are of high interest in situations where reorganization of neural networks can be observed, e.g., after stroke. However, an increasing number of studies suggest that improvements in motor performance of the stroke-affected hand following modulation of primary motor cortex (M1) excitability by rTMS shows a high interindividual variability. We here tested the hypothesis that in stroke patients the interindividual variability of behavioral response to excitatory rTMS is related to interindividual differences in network connectivity of the stimulated region. Chronic stroke patients ( n  = 14) and healthy controls ( n  = 12) were scanned with functional magnetic resonance imaging (fMRI) while performing a simple hand motor task. Dynamic causal modeling (DCM) was used to investigate effective connectivity of key motor regions. On two different days after the fMRI experiment, patients received either intermittent theta-burst stimulation (iTBS) over ipsilesional M1 or control stimulation over the parieto-occipital cortex. Motor performance and TMS parameters of cortical excitability were measured before and after iTBS. Our results revealed that patients with better motor performance of the affected hand showed stronger endogenous coupling between supplemental motor area (SMA) and M1 before starting the iTBS intervention. Applying iTBS to ipsilesional M1 significantly increased ipsilesional M1 excitability and decreased contralesional M1 excitability as compared to control stimulation. Individual behavioral improvements following iTBS specifically correlated with neural coupling strengths in the stimulated hemisphere prior to stimulation, especially for connections targeting the stimulated M1. Combining endogenous connectivity and behavioral parameters explained 82% of the variance in hand motor performance observed after iTBS. In conclusion, the data suggest that the

  15. FGF-2 induces behavioral recovery after early adolescent injury to the motor cortex of rats.

    PubMed

    Nemati, Farshad; Kolb, Bryan

    2011-11-20

    Motor cortex injuries in adulthood lead to poor performance in behavioral tasks sensitive to limb movements in the rat. We have shown previously that motor cortex injury on day 10 or day 55 allow significant spontaneous recovery but not injury in early adolescence (postnatal day 35 "P35"). Previous studies have indicated that injection of basic fibroblast growth factor (FGF-2) enhances behavioral recovery after neonatal cortical injury but such effect has not been studied following motor cortex lesions in early adolescence. The present study undertook to investigate the possibility of such behavioral recovery. Rats with unilateral motor cortex lesions were assigned to two groups in which they received FGF-2 or bovine serum albumin (BSA) and were tested in a number of behavioral tests (postural asymmetry, skilled reaching, sunflower seed manipulation, forepaw inhibition in swimming). Golgi-Cox analysis was used to examine the dendritic structure of pyramidal cells in the animals' parietal (layer III) and forelimb (layer V) area of the cortex. The results indicated that rats injected with FGF-2 (but not BSA) showed significant behavioral recovery that was associated with increased dendritic length and spine density. The present study suggests a role for FGF-2 in the recovery of function following injury during early adolescence. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Motor behaviors in the sheep evoked by electrical stimulation of the subthalamic nucleus.

    PubMed

    Lentz, Linnea; Zhao, Yan; Kelly, Matthew T; Schindeldecker, William; Goetz, Steven; Nelson, Dwight E; Raike, Robert S

    2015-11-01

    Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is used to treat movement disorders, including advanced Parkinson's disease (PD). The pathogenesis of PD and the therapeutic mechanisms of DBS are not well understood. Large animal models are essential for investigating the mechanisms of PD and DBS. The purpose of this study was to develop a novel sheep model of STN DBS and quantify the stimulation-evoked motor behaviors. To do so, a large sample of animals was chronically-implanted with commercial DBS systems. Neuroimaging and histology revealed that the DBS leads were implanted accurately relative to the neurosurgical plan and also precisely relative to the STN. It was also possible to repeatedly conduct controlled evaluations of stimulation-evoked motor behavior in the awake-state. The evoked motor responses depended on the neuroanatomical location of the electrode contact selected for stimulation, as contacts proximal to the STN evoked movements at significantly lower voltages. Tissue stimulation modeling demonstrated that selecting any of the contacts stimulated the STN, whereas selecting the relatively distal contacts often also stimulated thalamus but only the distal-most contact stimulated internal capsule. The types of evoked motor behaviors were specific to the stimulation frequency, as low but not high frequencies consistently evoked movements resembling human tremor or dyskinesia. Electromyography confirmed that the muscle activity underlying the tremor-like movements in the sheep was consistent with human tremor. Overall, this work establishes that the sheep is a viable a large-animal platform for controlled testing of STN DBS with objective motor outcomes. Moreover, the results support the hypothesis that exaggerated low-frequency activity within individual nodes of the motor network can drive symptoms of human movement disorders, including tremor and dyskinesia. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Identifying corals displaying aberrant behavior in Fiji’s Lau Archipelago

    PubMed Central

    Chen, Chii-Shiarng; Dempsey, Alexandra C.

    2017-01-01

    Abstract Given the numerous threats against Earth’s coral reefs, there is an urgent need to develop means of assessing reef coral health on a proactive timescale. Molecular biomarkers may prove useful in this endeavor because their expression should theoretically undergo changes prior to visible signs of health decline, such as the breakdown of the coral-dinoflagellate (genus Symbiodinium) endosymbiosis. Herein 13 molecular- and physiological-scale biomarkers spanning both eukaryotic compartments of the anthozoan-Symbiodinium mutualism were assessed across 70 pocilloporid coral colonies sampled from reefs of Fiji’s easternmost province, Lau. Eleven colonies were identified as outliers upon employment of a detection method based partially on the Mahalanobis distance; these corals were hypothesized to have been displaying aberrant sub-cellular behavior with respect to their gene expression signatures, as they were characterized not only by lower Symbiodinium densities, but also by higher levels of expression of several stress-targeted genes. Although these findings could suggest that the sampled colonies were physiologically compromised at the time of sampling, further studies are warranted to state conclusively whether these 11 scleractinian coral colonies are more stress-prone than nearby conspecifics that demonstrated statistically normal phenotypes. PMID:28542245

  18. The Feldenkrais Method: A Dynamic Approach to Changing Motor Behavior.

    ERIC Educational Resources Information Center

    Buchanan, Patricia A.; Ulrich, Beverly D.

    2001-01-01

    Describes the Feldenkrais Method of somatic education, noting parallels with a dynamic systems theory (DST) approach to motor behavior. Feldenkrais uses movement and perception to foster individualized improvement in function. DST explains that a human-environment system continually adapts to changing conditions and assembles behaviors…

  19. Differential genetic regulation of motor activity and anxiety-related behaviors in mice using an automated home cage task.

    PubMed

    Kas, Martien J H; de Mooij-van Malsen, Annetrude J G; Olivier, Berend; Spruijt, Berry M; van Ree, Jan M

    2008-08-01

    Traditional behavioral tests, such as the open field test, measure an animal's responsiveness to a novel environment. However, it is generally difficult to assess whether the behavioral response obtained from these tests relates to the expression level of motor activity and/or to avoidance of anxiogenic areas. Here, an automated home cage environment for mice was designed to obtain independent measures of motor activity levels and of sheltered feeding preference during three consecutive days. Chronic treatment with the anxiolytic drug chlordiazepoxide (5 and 10 mg/kg/day) in C57BL/6J mice reduced sheltered feeding preference without altering motor activity levels. Furthermore, two distinct chromosome substitution strains, derived from C57BL/6J (host strain) and A/J (donor strain) inbred strains, expressed either increased sheltering preference in females (chromosome 15) or reduced motor activity levels in females and males (chromosome 1) when compared to C57BL/6J. Longitudinal behavioral monitoring revealed that these phenotypic differences maintained after adaptation to the home cage. Thus, by using new automated behavioral phenotyping approaches, behavior can be dissociated into distinct behavioral domains (e.g., anxiety-related and motor activity domains) with different underlying genetic origin and pharmacological responsiveness.

  20. Causal Role of Motor Simulation in Turn-Taking Behavior.

    PubMed

    Hadley, Lauren V; Novembre, Giacomo; Keller, Peter E; Pickering, Martin J

    2015-12-16

    Overlap between sensory and motor representations has been documented for a range of human actions, from grasping (Rizzolatti et al., 1996b) to playing a musical instrument (Novembre and Keller, 2014). Such overlap suggests that individuals use motor simulation to predict the outcome of observed actions (Wolpert, 1997). Here we investigate motor simulation as a basis of human communication. Using a musical turn-taking task, we show that pianists call on motor representations of their partner's part to predict when to come in for their own turn. Pianists played alternating solos with a videoed partner, and double-pulse transcranial magnetic stimulation was applied around the turn-switch to temporarily disrupt processing in two cortical regions implicated previously in different forms of motor simulation: (1) the dorsal premotor cortex (dPMC), associated with automatic motor resonance during passive observation of hand actions, especially when the actions are familiar (Lahav et al., 2007); and (2) the supplementary motor area (SMA), involved in active motor imagery, especially when the actions are familiar (Baumann et al., 2007). Stimulation of the right dPMC decreased the temporal accuracy of pianists' (right-hand) entries relative to sham when the partner's (left-hand) part had been rehearsed previously. This effect did not occur for dPMC stimulation without rehearsal or for SMA stimulation. These findings support the role of the dPMC in predicting the time course of observed actions via resonance-based motor simulation during turn-taking. Because turn-taking spans multiple modes of human interaction, we suggest that simulation is a foundational mechanism underlying the temporal dynamics of joint action. Even during passive observation, seeing or hearing somebody execute an action from within our repertoire activates motor cortices of our brain. But what is the functional relevance of such "motor simulation"? By combining a musical duet task with a real

  1. Caregiver burden associated with behavioral and psychological symptoms of dementia in elderly people in the local community.

    PubMed

    Matsumoto, Naomi; Ikeda, Manabu; Fukuhara, Ryuji; Shinagawa, Shunichiro; Ishikawa, Tomohisa; Mori, Takaaki; Toyota, Yasutaka; Matsumoto, Teruhisa; Adachi, Hiroyoshi; Hirono, Nobutsugu; Tanabe, Hirotaka

    2007-01-01

    Despite many studies about the association between caregiver burden and behavioral and psychological symptoms of dementia (BPSD), there have been no population-based studies to evaluate caregiver burden associated with each BPSD. To evaluate caregiver burden associated with the individual BPSD in elderly people living in the community. The subjects were 67 participants with dementia living with their caregivers (diagnosed in the third Nakayama study): 51 Alzheimer's disease, 5 vascular dementia and 11 other. The Neuropsychiatric Inventory (NPI) and NPI Caregiver Distress Scale (NPI-D) were used to assess subjects' BPSD and related caregiver distress, respectively. In the subjects exhibiting BPSD, aberrant motor behavior had the highest mean NPI score, and depression/dysphoria had the lowest. Agitation/aggression had the highest mean NPI-D score, and euphoria/elation had the lowest. Delusion, agitation/aggression, apathy/indifference, irritability/lability and aberrant motor behavior showed a correlation between the NPI and NPI-D scores. The burden associated with BPSD is different for each symptom and does not always depend on frequency and severity of BPSD. These findings suggest that some symptoms, such as agitation/aggression and irritability/lability, may affect the caregivers significantly, although their frequency and severity are low. Copyright (c) 2007 S. Karger AG, Basel.

  2. Concurrent silent strokes impair motor function by limiting behavioral compensation.

    PubMed

    Faraji, Jamshid; Kurio, Kristyn; Metz, Gerlinde A

    2012-08-01

    Silent strokes occur more frequently than classic strokes; however, symptoms may go unreported in spite of lasting tissue damage. A silent stroke may indicate elevated susceptibility to recurrent stroke, which may eventually result in apparent and lasting impairments. Here we investigated if multiple silent strokes to the motor system challenge the compensatory capacity of the brain to cumulatively result in permanent functional deficits. Adult male rats with focal ischemia received single focal ischemic mini-lesions in the sensorimotor cortex (SMC) or the dorsolateral striatum (DLS), or multiple lesions affecting both SMC and DLS. The time course and outcome of motor compensation and recovery were determined by quantitative and qualitative assessment of skilled reaching and skilled walking. Rats with SMC or DLS lesion alone did not show behavioral deficits in either task. However, the combination of focal ischemic lesions in SMC and DLS perturbed skilled reaching accuracy and disrupted forelimb placement in the ladder rung walking task. These observations suggest that multiple focal infarcts, each resembling a silent stroke, gradually compromise the plastic capacity of the motor system to cause permanent motor deficits. Moreover, these findings support the notion that cortical and subcortical motor systems cooperate when adopting beneficial compensatory movement strategies. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Magnetothermal genetic deep brain stimulation of motor behaviors in awake, freely moving mice

    PubMed Central

    Zhang, Qian; Castellanos Rubio, Idoia; del Pino, Pablo

    2017-01-01

    Establishing how neurocircuit activation causes particular behaviors requires modulating the activity of specific neurons. Here, we demonstrate that magnetothermal genetic stimulation provides tetherless deep brain activation sufficient to evoke motor behavior in awake mice. The approach uses alternating magnetic fields to heat superparamagnetic nanoparticles on the neuronal membrane. Neurons, heat-sensitized by expressing TRPV1 are activated with magnetic field application. Magnetothermal genetic stimulation in the motor cortex evoked ambulation, deep brain stimulation in the striatum caused rotation around the body-axis, and stimulation near the ridge between ventral and dorsal striatum caused freezing-of-gait. The duration of the behavior correlated tightly with field application. This approach provides genetically and spatially targetable, repeatable and temporarily precise activation of deep-brain circuits without the need for surgical implantation of any device. PMID:28826470

  4. Investigation of the Association Between Motor Stereotypy Behavior With Fundamental Movement Skills, Adaptive Functioning, and Autistic Spectrum Disorder Symptomology in Children With Intellectual Disabilities.

    PubMed

    Powell, Joanne L; Pringle, Lydia; Greig, Matt

    2017-02-01

    Motor stereotypy behaviors are patterned, coordinated, repetitive behaviors that are particularly evident in those with an autistic spectrum disorder and intellectual disabilities. The extent to which motor stereotypy behavior severity is associated with motor skills and maladaptive behavior, measures of adaptive functioning, along with fundamental movement skills and degree of autistic spectrum disorder symptomology is assessed in this preliminary report. Twelve participants, aged 7 to 16 years, with a reported motor stereotypy behavior and either mild or severe intellectual disability comprising developmental or global delay took part in the study. Spearman rho correlational analysis showed that severity of motor stereotypy behavior was significantly positively correlated with autistic spectrum disorder symptomology ( P = .008) and maladaptive behavior ( P = .008) but not fundamental movement skills ( P > .05). An increase in fundamental movement skills score was associated with a decrease in autistic spectrum disorder symptomology ( P = .01) and an increase in motor skills ( P = .002). This study provides evidence showing a significant relationship between motor stereotypy behavior severity with degree of autistic spectrum disorder symptomology and maladaptive behavior.

  5. Distinct motor impairments of dopamine D1 and D2 receptor knockout mice revealed by three types of motor behavior.

    PubMed

    Nakamura, Toru; Sato, Asako; Kitsukawa, Takashi; Momiyama, Toshihiko; Yamamori, Tetsuo; Sasaoka, Toshikuni

    2014-01-01

    Both D1R and D2R knock out (KO) mice of the major dopamine receptors show significant motor impairments. However, there are some discrepant reports, which may be due to the differences in genetic background and experimental procedures. In addition, only few studies directly compared the motor performance of D1R and D2R KO mice. In this paper, we examined the behavioral difference among N10 congenic D1R and D2R KO, and wild type (WT) mice. First, we examined spontaneous motor activity in the home cage environment for consecutive 5 days. Second, we examined motor performance using the rota-rod task, a standard motor task in rodents. Third, we examined motor ability with the Step-Wheel task in which mice were trained to run in a motor-driven turning wheel adjusting their steps on foothold pegs to drink water. The results showed clear differences among the mice of three genotypes in three different types of behavior. In monitoring spontaneous motor activities, D1R and D2R KO mice showed higher and lower 24 h activities, respectively, than WT mice. In the rota-rod tasks, at a low speed, D1R KO mice showed poor performance but later improved, whereas D2R KO mice showed a good performance at early days without further improvement. When first subjected to a high speed task, the D2R KO mice showed poorer rota-rod performance at a low speed than the D1R KO mice. In the Step-Wheel task, across daily sessions, D2R KO mice increased the duration that mice run sufficiently close to the spout to drink water, and decreased time to touch the floor due to missing the peg steps and number of times the wheel was stopped, which performance was much better than that of D1R KO mice. These incongruent results between the two tasks for D1R and D2R KO mice may be due to the differences in the motivation for the rota-rod and Step-Wheel tasks, aversion- and reward-driven, respectively. The Step-Wheel system may become a useful tool for assessing the motor ability of WT and mutant mice.

  6. Determination of aberration center of Ronchigram for automated aberration correctors in scanning transmission electron microscopy.

    PubMed

    Sannomiya, Takumi; Sawada, Hidetaka; Nakamichi, Tomohiro; Hosokawa, Fumio; Nakamura, Yoshio; Tanishiro, Yasumasa; Takayanagi, Kunio

    2013-12-01

    A generic method to determine the aberration center is established, which can be utilized for aberration calculation and axis alignment for aberration corrected electron microscopes. In this method, decentering induced secondary aberrations from inherent primary aberrations are minimized to find the appropriate axis center. The fitness function to find the optimal decentering vector for the axis was defined as a sum of decentering induced secondary aberrations with properly distributed weight values according to the aberration order. Since the appropriate decentering vector is determined from the aberration values calculated at an arbitrary center axis, only one aberration measurement is in principle required to find the center, resulting in /very fast center search. This approach was tested for the Ronchigram based aberration calculation method for aberration corrected scanning transmission electron microscopy. Both in simulation and in experiments, the center search was confirmed to work well although the convergence to find the best axis becomes slower with larger primary aberrations. Such aberration center determination is expected to fully automatize the aberration correction procedures, which used to require pre-alignment of experienced users. This approach is also applicable to automated aperture positioning. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Investigation of Perceptual-Motor Behavior Across the Expert Athlete to Disabled Patient Skill Continuum can Advance Theory and Practical Application.

    PubMed

    Müller, Sean; Vallence, Ann-Maree; Winstein, Carolee

    2017-12-14

    A framework is presented of how theoretical predictions can be tested across the expert athlete to disabled patient skill continuum. Common-coding theory is used as the exemplar to discuss sensory and motor system contributions to perceptual-motor behavior. Behavioral and neural studies investigating expert athletes and patients recovering from cerebral stroke are reviewed. They provide evidence of bi-directional contributions of visual and motor systems to perceptual-motor behavior. Majority of this research is focused on perceptual-motor performance or learning, with less on transfer. The field is ripe for research designed to test theoretical predictions across the expert athlete to disabled patient skill continuum. Our view has implications for theory and practice in sports science, physical education, and rehabilitation.

  8. Risky behaviors associated with pediatric pedestrians and bicyclists struck by motor vehicles.

    PubMed

    Glass, Nina E; Frangos, Spiros G; Simon, Ronald J; Bholat, Omar S; Todd, S Rob; Wilson, Chad; Jacko, Sally; Slaughter, Dekeya; Foltin, George; Levine, Deborah A

    2014-06-01

    Road safety constitutes a crisis with important health and economic impacts. In 2010, 11,000 pedestrians and 3500 bicyclists were injured by motor vehicles in New York City (NYC). Motor vehicle injuries represent the second leading cause of injury-related deaths in NYC children aged 5 to 14 years. To better target injury prevention strategies, we evaluated demographics, behaviors, environmental factors, injuries, and outcomes of pediatric pedestrians and bicyclists struck by motor vehicles in NYC. Pediatric data were extracted from a prospectively collected database of pedestrians and bicyclists struck by motor vehicles and treated at a level I regional trauma center between December 2008 and June 2011. Patients, guardians, and first responders were interviewed and medical records were reviewed. Institutional review board approval was granted and verbal consent was obtained. Of the 1457 patients, 168 (12%) were younger than 18 years. Compared with injured adults, children were more likely to be in male sex (69% vs 53%), to have minor injuries (83% vs 73% for injury severity scores of <9), and to be discharged without admission (69% vs 67%). Midblock crossings were more common in children pedestrians than in adults (37% vs 19%), often despite supervision (48%). Electronic device use among teenagers aged 13 to 17 years was nearly 3 times that of adults (28% vs 11%). Risky behaviors are common among pediatric pedestrians and bicyclists injured by motor vehicles. Road safety education and prevention strategies must stress compliance with traffic laws, readdress the importance of supervision, and reinforce avoidance of common distractors including electronic devices.

  9. The relationship of motor skills and adaptive behavior skills in young children with autism spectrum disorders.

    PubMed

    MacDonald, Megan; Lord, Catherine; Ulrich, Dale

    2013-11-01

    To determine the relationship of motor skills and the core behaviors of young children with autism, social affective skills and repetitive behaviors, as indicated through the calibrated autism severity scores. The univariate GLM tested the relationship of gross and fine motor skills measured by the gross motor scale and the fine motor scale of the MSEL with autism symptomology as measured by calibrated autism severity scores. Majority of the data collected took place in an autism clinic. A cohort of 159 young children with ASD (n=110), PDD-NOS (n=26) and non-ASD (developmental delay, n=23) between the ages of 12-33 months were recruited from early intervention studies and clinical referrals. Children with non-ASD (developmental delay) were included in this study to provide a range of scores indicted through calibrated autism severity. Not applicable. The primary outcome measures in this study were calibrated autism severity scores. Fine motor skills and gross motor skills significantly predicted calibrated autism severity (p < 0.01). Children with weaker motor skills displayed higher levels of calibrated autism severity. The fine and gross motor skills are significantly related to autism symptomology. There is more to focus on and new avenues to explore in the realm of discovering how to implement early intervention and rehabilitation for young children with autism and motor skills need to be a part of the discussion.

  10. Aberration compensation in a Skew parametric-resonance ionization cooling channel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sy, Amy V.; Derbenev, Yaroslav S.; Morozov, Vasiliy

    Skew Parametric-resonance Ionization Cooling (Skew PIC) represents a novel method for focusing of highly divergent particle beams, as in the final 6D cooling stage of a high-luminosity muon collider. In the muon collider concept, the resultant equilibrium transverse emittances from cooling with Skew PIC are an order of magnitude smaller than in conventional ionization cooling. The concept makes use of coupling of the transverse dynamic behavior, and the linear dynamics are well-behaved with good agreement between analytic solutions and simulation results. Compared to the uncoupled system, coupling of the transverse dynamic behavior purports to reduce the number of multipoles requiredmore » for aberration compensation while also avoiding unwanted resonances. Aberration compensation is more complicated in the coupled case, especially in the high-luminosity muon collider application where equilibrium angular spreads in the cooling channel are on the order of 200 mrad. We present recent progress on aberration compensation for control of highly divergent muon beams in the coupled correlated optics channel, and a simple cooling model to test the transverse acceptance of the channel.« less

  11. Relations of Preschoolers’ Visual Motor and Object Manipulation Skills with Executive Function and Social Behavior

    PubMed Central

    MacDonald, Megan; Lipscomb, Shannon; McClelland, Megan M.; Duncan, Rob; Becker, Derek; Anderson, Kim; Kile, Molly

    2017-01-01

    Purpose The purpose was to examine specific linkages between early visual-motor integration skills and executive function, as well as between early object manipulation skills and social behaviors in the classroom over the preschool year. Method 92 children between the ages of 3–5 years old (mean age 4.31 years) were recruited to participate. Comprehensive measures of visual motor integration skills, object manipulation skills, executive function and social behaviors were administered in the fall and spring of the preschool year. Results Our findings indicated that children who had better visual-motor integration skills in the fall had better executive function scores, (B = .47 [.20], p < .05, β = .27) in the spring of the preschool year after controlling for age, gender, Head-Start status, and site location, but not after controlling for children’s baseline levels of executive function. In addition, children who demonstrated better object-manipulation skills in the fall showed significantly stronger social behavior in their classrooms (as rated by teachers) in the spring, including more self-control, (B −.03 [.00], p < .05, β = .40), more cooperation, (B = .02 [.01], p < .05, β = .28), and less externalizing/hyperactivity, (B = −.02 [.01], p < .05, β = −.28) after controlling for social behavior in the fall and other covariates. Conclusion Children’s visual motor integration and object manipulation skills in the fall have modest to moderate relations with executive function and social behaviors later in the preschool year. These findings have implications for early learning initiatives and school readiness. PMID:27732149

  12. Low-order aberration sensitivity of eighth-order coronagraph masks

    NASA Technical Reports Server (NTRS)

    Shaklan, Stuart B.; Green, Joseph J.

    2005-01-01

    In a recent paper, Kuchner, Crepp, and Ge describe new image-plane coronagraph mask designs that reject to eighth order the leakage of starlight caused by image motion at the mask, resulting in a substantial relaxation of image centroiding requirements compared to previous fourth-order and second-order masks. They also suggest that the new masks are effective at rejecting leakage caused by low-order aberrations (e.g., focus, coma, and astigmatism). In this paper, we derive the sensitivity of eighth-order masks to aberrations of any order and provide simulations of coronagraph behavior in the presence of optical aberrations.We find that the masks leak light as the fourth power of focus, astigmatism, coma, and trefoil. This has tremendous performance advantages for the Terrestrial Planet Finder Coronagraph.

  13. Behavioral Prescription Guide. Manual IIb: Motor. Parent/Child Home Stimulation 'The Marshalltown Project.'

    ERIC Educational Resources Information Center

    Keiser, Arlene F.; And Others

    Presented is the Marshalltown Behavioral Prescription Guide for motor development which consists of incremental behavioral objectives and strategies to aid parents in the prescriptive teaching of handicapped and culturally deprived infants and preschool children. The guide is intended for use prior to a weekly home visit resulting in a weekly…

  14. Distinct motor impairments of dopamine D1 and D2 receptor knockout mice revealed by three types of motor behavior

    PubMed Central

    Nakamura, Toru; Sato, Asako; Kitsukawa, Takashi; Momiyama, Toshihiko; Yamamori, Tetsuo; Sasaoka, Toshikuni

    2014-01-01

    Both D1R and D2R knock out (KO) mice of the major dopamine receptors show significant motor impairments. However, there are some discrepant reports, which may be due to the differences in genetic background and experimental procedures. In addition, only few studies directly compared the motor performance of D1R and D2R KO mice. In this paper, we examined the behavioral difference among N10 congenic D1R and D2R KO, and wild type (WT) mice. First, we examined spontaneous motor activity in the home cage environment for consecutive 5 days. Second, we examined motor performance using the rota-rod task, a standard motor task in rodents. Third, we examined motor ability with the Step-Wheel task in which mice were trained to run in a motor-driven turning wheel adjusting their steps on foothold pegs to drink water. The results showed clear differences among the mice of three genotypes in three different types of behavior. In monitoring spontaneous motor activities, D1R and D2R KO mice showed higher and lower 24 h activities, respectively, than WT mice. In the rota-rod tasks, at a low speed, D1R KO mice showed poor performance but later improved, whereas D2R KO mice showed a good performance at early days without further improvement. When first subjected to a high speed task, the D2R KO mice showed poorer rota-rod performance at a low speed than the D1R KO mice. In the Step-Wheel task, across daily sessions, D2R KO mice increased the duration that mice run sufficiently close to the spout to drink water, and decreased time to touch the floor due to missing the peg steps and number of times the wheel was stopped, which performance was much better than that of D1R KO mice. These incongruent results between the two tasks for D1R and D2R KO mice may be due to the differences in the motivation for the rota-rod and Step-Wheel tasks, aversion- and reward-driven, respectively. The Step-Wheel system may become a useful tool for assessing the motor ability of WT and mutant mice. PMID

  15. Motor nerve transplantation.

    PubMed

    Gray, W P; Keohane, C; Kirwan, W O

    1997-10-01

    The motor nerve transplantation (MNT) technique is used to transfer an intact nerve into a denervated muscle by harvesting a neurovascular pedicle of muscle containing motor endplates from the motor endplate zone of a donor muscle and implanting it into a denervated muscle. Thirty-six adult New Zealand White rabbits underwent reinnervation of the left long peroneal (LP) muscle (fast twitch) with a motor nerve graft from the soleus muscle (slow twitch). The right LP muscle served as a control. Reinnervation was assessed using microstimulatory single-fiber electromyography (SFEMG), alterations in muscle fiber typing and grouping, and isometric response curves. Neurofilament antibody was used for axon staining. The neurofilament studies provided direct evidence of nerve growth from the motor nerve graft into the adjacent denervated muscle. Median motor endplate jitter was 13 microsec preoperatively, and 26 microsec at 2 months, 29.5 microsec at 4 months, and 14 microsec at 6 months postoperatively (p < 0.001). Isometric tetanic tension studies showed a progressive functional recovery in the reinnervated muscle over 6 months. There was no histological evidence of aberrant reinnervation from any source outside the nerve pedicle. Isometric twitch responses and adenosine triphosphatase studies confirmed the conversion of the reinnervated LP muscle to a slow-type muscle. Acetylcholinesterase studies confirmed the presence of functioning motor endplates beneath the insertion of the motor nerve graft. It is concluded that the MNT technique achieves motor reinnervation by growth of new nerve fibers across the pedicle graft into the recipient muscle.

  16. Self-reported risk-taking behaviors and hospitalization for motor vehicle injury among active duty army personnel.

    PubMed

    Bell, N S; Amoroso, P J; Yore, M M; Smith, G S; Jones, B H

    2000-04-01

    Motor vehicle crashes are a leading cause of injury in the Army. Behaviors increasing risk for motor vehicle crashes are also prevalent, but research has not linked these behaviors directly to injury outcomes (e.g., hospitalizations). To evaluate the relationship between behavior and motor vehicle crash injuries, 99, 981 Army personnel who completed Health Risk Appraisal surveys in 1992 were followed for up to 6 years. Cox proportional hazards modeling was used to evaluate speeding, seat belt use, drinking patterns, and demographics. A total of 429 soldiers were hospitalized for motor vehicle injury. Unadjusted analyses revealed that heavy drinking, drinking and driving, speeding, low seat belt use, younger age, minority race/ethnicity, and enlisted rank were significantly associated with motor vehicle injury, but neither smoking nor gender was. Multivariate models showed a significant trend of increasing injury risk with younger ages. Soldiers under age 21 were injured almost five times more often than those over age 40 (HR 4.89, 2.56-9.33). Also associated with risk for hospitalizations were minority race (HR 1.78, 1.46-2.18), heaviest drinkers versus abstainers (HR 1.81, 1.11-2.94), and seat belt use of 50% or less versus 100% (HR 1.40, 1.07-1.85). Although nonsignificant, there was evidence of an age-drinking interaction where the difference in injury risk between those older and those younger than 21 was greatest at low alcohol consumption levels. Modifiable risk factors associated with motor vehicle injuries include heavy drinking and low seat belt use. Programs targeting these behaviors that meet the needs of young and minority soldiers are needed. The high density of young, at-risk soldiers residing in base housing may provide a unique opportunity for a residential intervention program.

  17. The relationship of motor skills and adaptive behavior skills in young children with autism spectrum disorders

    PubMed Central

    MacDonald, Megan; Lord, Catherine; Ulrich, Dale

    2015-01-01

    Objective To determine the relationship of motor skills and the core behaviors of young children with autism, social affective skills and repetitive behaviors, as indicated through the calibrated autism severity scores. Design The univariate GLM tested the relationship of gross and fine motor skills measured by the gross motor scale and the fine motor scale of the MSEL with autism symptomology as measured by calibrated autism severity scores. Setting Majority of the data collected took place in an autism clinic. Participants A cohort of 159 young children with ASD (n=110), PDD-NOS (n=26) and non-ASD (developmental delay, n=23) between the ages of 12–33 months were recruited from early intervention studies and clinical referrals. Children with non-ASD (developmental delay) were included in this study to provide a range of scores indicted through calibrated autism severity. Interventions Not applicable. Main Outcome Measures The primary outcome measures in this study were calibrated autism severity scores. Results Fine motor skills and gross motor skills significantly predicted calibrated autism severity (p < 0.01). Children with weaker motor skills displayed higher levels of calibrated autism severity. Conclusions The fine and gross motor skills are significantly related to autism symptomology. There is more to focus on and new avenues to explore in the realm of discovering how to implement early intervention and rehabilitation for young children with autism and motor skills need to be a part of the discussion. PMID:25774214

  18. Influence of alignment errors of a telescope system on its aberration field

    NASA Astrophysics Data System (ADS)

    Shack, R. V.; Thompson, K.

    1980-01-01

    The study of aberrations in a system is considered. It is pointed out that a system in which the elements are tilted and decentered has no axial symmetry, and in fact no symmetry at all if the tilts, and decentrations are not coplanar. It is customary in such a case to give up on an aberration-theoretic treatment and simply trace enough rays to produce a set of spot diagrams for various points in the field. However, in connection with the lack of symmetry, it is necessary to select a relatively large number of points. The considered investigation is concerned with an aberration-theoretic approach which can be applied to such systems. This approach provides insight into the field behavior of the aberrations with great economy in the calculation. It is based on a concept suggested by Buchroeder (1976). In the given case, this concept considers for the component fields corresponding to the various surfaces centers of symmetry which do not coincide. Attention is given to the procedure for locating the centers of symmetry, aberrations fields, spherical aberration, and various types of astigmatism.

  19. Item response theory and the measurement of motor behavior.

    PubMed

    Safrit, M J; Cohen, A S; Costa, M G

    1989-12-01

    Item response theory (IRT) has been the focus of intense research and development activity in educational and psychological measurement during the past decade. Because this theory can provide more precise information about test items than other theories usually used in measuring motor behavior, the application of IRT in physical education and exercise science merits investigation. In IRT, the difficulty level of each item (e.g., trial or task) can be estimated and placed on the same scale as the ability of the examinee. Using this information, the test developer can determine the ability levels at which the test functions best. Equating the scores of individuals on two or more items or tests can be handled efficiently by applying IRT. The precision of the identification of performance standards in a mastery test context can be enhanced, as can adaptive testing procedures. In this tutorial, several potential benefits of applying IRT to the measurement of motor behavior were described. An example is provided using bowling data and applying the graded-response form of the Rasch IRT model. The data were calibrated and the goodness of fit was examined. This analysis is described in a step-by-step approach. Limitations to using an IRT model with a test consisting of repeated measures were noted.

  20. Relations of Preschoolers' Visual-Motor and Object Manipulation Skills With Executive Function and Social Behavior.

    PubMed

    MacDonald, Megan; Lipscomb, Shannon; McClelland, Megan M; Duncan, Rob; Becker, Derek; Anderson, Kim; Kile, Molly

    2016-12-01

    The purpose of this article was to examine specific linkages between early visual-motor integration skills and executive function, as well as between early object manipulation skills and social behaviors in the classroom during the preschool year. Ninety-two children aged 3 to 5 years old (M age  = 4.31 years) were recruited to participate. Comprehensive measures of visual-motor integration skills, object manipulation skills, executive function, and social behaviors were administered in the fall and spring of the preschool year. Our findings indicated that children who had better visual-motor integration skills in the fall had better executive function scores (B = 0.47 [0.20], p < .05, β = .27) in the spring of the preschool year after controlling for age, gender, Head Start status, and site location, but not after controlling for children's baseline levels of executive function. In addition, children who demonstrated better object manipulation skills in the fall showed significantly stronger social behavior in their classrooms (as rated by teachers) in the spring, including more self-control (B - 0.03 [0.00], p < .05, β = .40), more cooperation (B = 0.02 [0.01], p < .05, β = .28), and less externalizing/hyperactivity (B = - 0.02 [0.01], p < .05, β = - .28) after controlling for social behavior in the fall and other covariates. Children's visual-motor integration and object manipulation skills in the fall have modest to moderate relations with executive function and social behaviors later in the preschool year. These findings have implications for early learning initiatives and school readiness.

  1. Efficacy of parent-delivered behavioral therapy for primary complex motor stereotypies.

    PubMed

    Specht, Matthew W; Mahone, E Mark; Kline, Tina; Waranch, Richard; Brabson, Laurel; Thompson, Carol B; Singer, Harvey S

    2017-02-01

    Primary complex motor stereotypies (CMS) are persistent, patterned, repetitive, rhythmic movements in young people with typical development. This study evaluated the efficacy of an instructional DVD as a home-based, parent-administered, behavioral therapy for primary CMS. Eighty-one children with primary CMS were enrolled. Primary outcome measures included the Stereotypy Severity Scale (SSS) - Motor and Impairment scores, and Stereotypy Linear Analog Scale (SLAS). Mean CMS onset was 13.4 months (SD 13.1). Eligibility required observed CMS. Psychiatric disorders were not exclusionary and a stable medication regimen was required. Intellectual disability, neurological disorder, autism spectrum disorder, and tics were exclusionary. Initial assessments were completed via REDCap before receipt of the DVD. Fifty-four of the 81 children (34 male, 20 female; mean age 8y 2mo, SD 1.42, range 7-14y) completed assessments at 1, 2, or 3 months after receiving the DVD. Reductions (baseline to last assessment) in SSS Motor, SSS Impairment, and SLAS scores (all p<0.001) represented change ratios of -15%, -24%, and a -20% respectively. Greatest relative treatment benefit was observed by younger children (ages 7-8y), and by 1 month after receipt of DVD, while a parent global assessment scale showed progressive improvement throughout the study. An instructional DVD for parent-delivered behavioral therapy was a safe, effective intervention for primary CMS. © 2016 Mac Keith Press.

  2. Interpreting Chromosome Aberration Spectra

    NASA Technical Reports Server (NTRS)

    Levy, Dan; Reeder, Christopher; Loucas, Bradford; Hlatky, Lynn; Chen, Allen; Cornforth, Michael; Sachs, Rainer

    2007-01-01

    Ionizing radiation can damage cells by breaking both strands of DNA in multiple locations, essentially cutting chromosomes into pieces. The cell has enzymatic mechanisms to repair such breaks; however, these mechanisms are imperfect and, in an exchange process, may produce a large-scale rearrangement of the genome, called a chromosome aberration. Chromosome aberrations are important in killing cells, during carcinogenesis, in characterizing repair/misrepair pathways, in retrospective radiation biodosimetry, and in a number of other ways. DNA staining techniques such as mFISH ( multicolor fluorescent in situ hybridization) provide a means for analyzing aberration spectra by examining observed final patterns. Unfortunately, an mFISH observed final pattern often does not uniquely determine the underlying exchange process. Further, resolution limitations in the painting protocol sometimes lead to apparently incomplete final patterns. We here describe an algorithm for systematically finding exchange processes consistent with any observed final pattern. This algorithm uses aberration multigraphs, a mathematical formalism that links the various aspects of aberration formation. By applying a measure to the space of consistent multigraphs, we will show how to generate model-specific distributions of aberration processes from mFISH experimental data. The approach is implemented by software freely available over the internet. As a sample application, we apply these algorithms to an aberration data set, obtaining a distribution of exchange cycle sizes, which serves to measure aberration complexity. Estimating complexity, in turn, helps indicate how damaging the aberrations are and may facilitate identification of radiation type in retrospective biodosimetry.

  3. Distributed effects of biological sex define sex-typical motor behavior in Caenorhabditis elegans.

    PubMed

    Mowrey, William R; Bennett, Jessica R; Portman, Douglas S

    2014-01-29

    Sex differences in shared behaviors (for example, locomotion and feeding) are a nearly universal feature of animal biology. Though these behaviors may share underlying neural programs, their kinematics can exhibit robust differences between males and females. The neural underpinnings of these differences are poorly understood because of the often-untested assumption that they are determined by sex-specific body morphology. Here, we address this issue in the nematode Caenorhabditis elegans, which features two sexes with distinct body morphologies but similar locomotor circuitry and body muscle. Quantitative behavioral analysis shows that C. elegans and related nematodes exhibit significant sex differences in the dynamics and geometry of locomotor body waves, such that the male is generally faster. Using a recently proposed model of locomotor wave propagation, we show that sex differences in both body mechanics and the intrinsic dynamics of the motor system can contribute to kinematic differences in distinct mechanical contexts. By genetically sex-reversing the properties of specific tissues and cells, however, we find that sex-specific locomotor frequency in C. elegans is determined primarily by the functional modification of shared sensory neurons. Further, we find that sexual modification of body wall muscle together with the nervous system is required to alter body wave speed. Thus, rather than relying on a single focus of modification, sex differences in motor dynamics require independent modifications to multiple tissue types. Our results suggest shared motor behaviors may be sex-specifically optimized though distributed modifications to several aspects of morphology and physiology.

  4. Distributed Effects of Biological Sex Define Sex-Typical Motor Behavior in Caenorhabditis elegans

    PubMed Central

    Mowrey, William R.; Bennett, Jessica R.

    2014-01-01

    Sex differences in shared behaviors (for example, locomotion and feeding) are a nearly universal feature of animal biology. Though these behaviors may share underlying neural programs, their kinematics can exhibit robust differences between males and females. The neural underpinnings of these differences are poorly understood because of the often-untested assumption that they are determined by sex-specific body morphology. Here, we address this issue in the nematode Caenorhabditis elegans, which features two sexes with distinct body morphologies but similar locomotor circuitry and body muscle. Quantitative behavioral analysis shows that C. elegans and related nematodes exhibit significant sex differences in the dynamics and geometry of locomotor body waves, such that the male is generally faster. Using a recently proposed model of locomotor wave propagation, we show that sex differences in both body mechanics and the intrinsic dynamics of the motor system can contribute to kinematic differences in distinct mechanical contexts. By genetically sex-reversing the properties of specific tissues and cells, however, we find that sex-specific locomotor frequency in C. elegans is determined primarily by the functional modification of shared sensory neurons. Further, we find that sexual modification of body wall muscle together with the nervous system is required to alter body wave speed. Thus, rather than relying on a single focus of modification, sex differences in motor dynamics require independent modifications to multiple tissue types. Our results suggest shared motor behaviors may be sex-specifically optimized though distributed modifications to several aspects of morphology and physiology. PMID:24478342

  5. Light Treatment for Neuropsychiatric Behaviors in Alzheimer’s Disease

    PubMed Central

    Dowling, Glenna A.; Graf, Carla; Hubbard, Erin M.; Luxenberg, Jay S.

    2008-01-01

    Neuropsychiatric behaviors are common in people with Alzheimer’s disease (AD) and make both professional and lay caregiving difficult. Light therapy has been somewhat successful in ameliorating disruptive behaviors. This randomized trial tested the effects of morning or afternoon bright light exposure compared with usual indoor light on the presence, frequency, severity, and occupational disruptiveness of neuropsychiatric behaviors in nursing home residents with AD. Light was administered for 1 hr daily (Monday–Friday) for 10 weeks. The Neuropsychiatric Inventory–Nursing Home was used to assess behavior at baseline and end of the intervention. Analyses revealed statistically significant differences between groups on agitation/aggression, depression/dysphoria, aberrant motor behavior, and appetite/eating disorders. The magnitude of change was small and may not represent clinically significant findings. Agitation/aggression and nighttime behaviors commonly occurred and were highly correlated with occupational disruptiveness. Interventions that decrease the presence and/or severity of neuropsychiatric behaviors have the potential to significantly decrease caregiver burden. PMID:17596638

  6. Examination of Poststroke Alteration in Motor Unit Firing Behavior Using High-Density Surface EMG Decomposition.

    PubMed

    Li, Xiaoyan; Holobar, Ales; Gazzoni, Marco; Merletti, Roberto; Rymer, William Zev; Zhou, Ping

    2015-05-01

    Recent advances in high-density surface electromyogram (EMG) decomposition have made it a feasible task to discriminate single motor unit activity from surface EMG interference patterns, thus providing a noninvasive approach for examination of motor unit control properties. In the current study, we applied high-density surface EMG recording and decomposition techniques to assess motor unit firing behavior alterations poststroke. Surface EMG signals were collected using a 64-channel 2-D electrode array from the paretic and contralateral first dorsal interosseous (FDI) muscles of nine hemiparetic stroke subjects at different isometric discrete contraction levels between 2 to 10 N with a 2 N increment step. Motor unit firing rates were extracted through decomposition of the high-density surface EMG signals and compared between paretic and contralateral muscles. Across the nine tested subjects, paretic FDI muscles showed decreased motor unit firing rates compared with contralateral muscles at different contraction levels. Regression analysis indicated a linear relation between the mean motor unit firing rate and the muscle contraction level for both paretic and contralateral muscles (p < 0.001), with the former demonstrating a lower increment rate (0.32 pulses per second (pps)/N) compared with the latter (0.67 pps/N). The coefficient of variation (averaged over the contraction levels) of the motor unit firing rates for the paretic muscles (0.21 ± 0.012) was significantly higher than for the contralateral muscles (0.17 ± 0.014) (p < 0.05). This study provides direct evidence of motor unit firing behavior alterations poststroke using surface EMG, which can be an important factor contributing to hemiparetic muscle weakness.

  7. Change the Collective Behaviors of Colloidal Motors by Tuning Electrohydrodynamic Flow at the Subparticle Level.

    PubMed

    Yang, Xingfu; Wu, Ning

    2018-01-23

    As demonstrated in biological systems, breaking the symmetry of surrounding hydrodynamic flow is the key to achieve autonomous locomotion of microscopic objects. In recent years, a variety of synthetic motors have been developed based on different propulsion mechanisms. Most work, however, focuses on the propulsion of individual motors. Here, we study the collective behaviors of colloidal dimers actuated by a perpendicularly applied AC electric field, which controls the electrohydrodynamic flow at subparticle levels. Although these motors experience strong dipolar repulsion from each other and are highly active, surprisingly, they assemble into a family of stable planar clusters with handedness. We show that this type of unusual structure arises from the contractile hydrodynamic flow around small lobes but extensile flow around the large lobes. We further reveal that the collective behavior, assembled structure, and assembly dynamics of these motors all depend on the specific directions of electrohydrodynamic flow surrounding each lobe of the dimers. By fine-tuning the surface charge asymmetry on particles and salt concentration in solution, we demonstrate the ability to control their collective behaviors on demand. This novel type of active assembly via hydrodynamic interactions has the potential to grow monodisperse clusters in a self-limiting fashion. The underlying concept revealed in this work should also apply to other types of active and asymmetric particles.

  8. Improvement in motor and exploratory behavior in Rett syndrome mice with restricted ketogenic and standard diets.

    PubMed

    Mantis, John G; Fritz, Christie L; Marsh, Jeremy; Heinrichs, Stephen C; Seyfried, Thomas N

    2009-06-01

    Rett syndrome (RTT) is a rare X-linked autistic-spectrum neurological disorder associated with impaired energy metabolism, seizure susceptibility, progressive social behavioral regression, and motor impairment primarily in young girls. The objective of this study was to examine the influence of restricted diets, including a ketogenic diet (KD) and a standard rodent chow diet (SD), on behavior in male Mecp2(308/y) mice, a model of RTT. The KD is a high-fat, low-carbohydrate diet that has anticonvulsant efficacy in children with intractable epilepsy and may be therapeutic in children with RTT. Following an 11-day pretrial period, adult wild-type and mutant Rett mice were separated into groups that were fed either an SD in unrestricted or restricted amounts or a ketogenic diet (KetoCal) in restricted amounts for a total of 30 days. The restricted diets were administered to reduce mouse body weight by 20-23% compared to the body weight of each mouse before the initiation of the diet. All mice were subjected to a battery of behavioral tests to determine the influence of the diet on the RTT phenotype. We found that performance in tests of motor behavior and anxiety was significantly worse in male RTT mice compared to wild-type mice and that restriction of either the KD or the SD improved motor behavior and reduced anxiety. We conclude that although both restricted diets increased the tendency of Rett mice to explore a novel environment, the beneficial effects of the KD were due more to calorie restriction than to the composition of the diet. Our findings suggest that calorically restricted diets could be effective in reducing the anxiety and in improving motor behavior in girls with RTT.

  9. Gestational exposure to perfluorooctanoic acid (PFOA): alterations in motor related behaviors

    PubMed Central

    Goulding, David R.; White, Sally S.; McBride, Sandra J.; Fenton, Suzanne E.; Harry, G. Jean

    2016-01-01

    Perfluoroalkyl and polyfluoroalkyl substances are used in commercial applications and developmental exposure has been implicated in alterations in neurobehavioral functioning. While associations between developmental perfluorooctanoic acid (PFOA) exposure and human outcomes have been inconsistent, studies in experimental animals suggest alterations in motor related behaviors. To examine a dose-response pattern of neurobehavioral effects following gestational exposure to PFOA, pregnant CD-1 mice received PFOA (0, 0.1, 0.3, 1.0 mg/kg/day) via oral gavage from gestational day 1–17 and the male offspring examined. Motor activity assessments on postnatal day (PND)18, 19, and 20 indicated a shift in the developmental pattern with an elevated activity level observed in the 1.0 mg/kg/day dose group on PND18. In the adult, no alterations were observed in body weights, activity levels, diurnal pattern of running wheel activity, startle response, or pre-pulse startle inhibition. In response to a subcutaneous injection of saline or nicotine (80 µg/kg), all animals displayed a transient increase in activity likely associated with handling with no differences observed across dose groups. Inhibition of motor activity over 18 days of 400µg/kg nicotine injection was not significantly different across dose groups. Hyperactivity induced by 2mg/kg (+)-methamphetamine hydrochloride intraperitoneal injection was significantly lower in the 1.0 mg/kg/day PFOA dose group as compared to controls. Taken together, these data suggest that the effects on motor-related behaviors with gestational PFOA exposure do not mimic those reported for acute postnatal exposure. Changes were not observed at dose level under 1.0 mg/kg/day PFOA. Further examination of pathways associated with methamphetamine-induced activity is warranted. PMID:27888120

  10. Why New Spinal Cord Plasticity Does Not Disrupt Old Motor Behaviors.

    PubMed

    Chen, Yi; Chen, Lu; Wang, Yu; Chen, Xiang Yang; Wolpaw, Jonathan R

    2017-08-23

    When new motor learning changes the spinal cord, old behaviors are not impaired; their key features are preserved by additional compensatory plasticity. To explore the mechanisms responsible for this compensatory plasticity, we transected the spinal dorsal ascending tract before or after female rats acquired a new behavior-operantly conditioned increase or decrease in the right soleus H-reflex-and examined an old behavior-locomotion. Neither spinal dorsal ascending tract transection nor H-reflex conditioning alone impaired locomotion. Nevertheless, when spinal dorsal ascending tract transection and H-reflex conditioning were combined, the rats developed a limp and a tilted posture that correlated in direction and magnitude with the H-reflex change. When the right H-reflex was increased by conditioning, the right step lasted longer than the left and the right hip was higher than the left; when the right H-reflex was decreased by conditioning, the opposite occurred. These results indicate that ascending sensory input guides the compensatory plasticity that normally prevents the plasticity underlying H-reflex change from impairing locomotion. They support the concept of the state of the spinal cord as a negotiated equilibrium that reflects the concurrent influences of all the behaviors in an individual's repertoire; and they support the new therapeutic strategies this concept introduces. SIGNIFICANCE STATEMENT The spinal cord provides a reliable final common pathway for motor behaviors throughout life. Until recently, its reliability was explained by the assumption that it is hardwired; but it is now clear that the spinal cord changes continually as new behaviors are acquired. Nevertheless, old behaviors are preserved. This study shows that their preservation depends on sensory feedback from the spinal cord to the brain: if feedback is removed, the acquisition of a new behavior may disrupt an old behavior. In sum, when a new behavior changes the spinal cord, sensory

  11. The effect of spherical aberration on the phase singularities of focused dark-hollow Gaussian beams

    NASA Astrophysics Data System (ADS)

    Luo, Yamei; Lü, Baida

    2009-06-01

    The phase singularities of focused dark-hollow Gaussian beams in the presence of spherical aberration are studied. It is shown that the evolution behavior of phase singularities of focused dark-hollow Gaussian beams in the focal region depends not only on the truncation parameter and beam order, but also on the spherical aberration. The spherical aberration leads to an asymmetric spatial distribution of singularities outside the focal plane and to a shift of singularities near the focal plane. The reorganization process of singularities and spatial distribution of singularities are additionally dependent on the sign of the spherical aberration. The results are illustrated by numerical examples.

  12. Efficacy of parent-delivered behavioral therapy for primary complex motor stereotypies

    PubMed Central

    Specht, Matthew W; Mahone, E Mark; Kline, Tina; Waranch, Richard; Brabson, Laurel; Thompson, Carol B; Singer, Harvey S

    2016-01-01

    Aim ‘Primary’ complex motor stereotypies (CMS) are persistent, patterned, repetitive, rhythmic movements in young people with typical development. This study evaluated the efficacy of an instructional DVD as a home-based, parent-administered, behavioral therapy for primary CMS. Method Eighty-one children with primary CMS were enrolled. Primary outcome measures included the Stereotypy Severity Scale (SSS) – Motor and Impairment scores, and Stereotypy Linear Analog Scale (SLAS). Mean CMS onset was 13.4 months (SD 13.1). Eligibility required observed CMS. Psychiatric disorders were not exclusionary and a stable medication regimen was required. Intellectual disability, neurological disorder, autism spectrum disorder, and tics were exclusionary. Initial assessments were completed via REDCap before receipt of the DVD. Fifty-four of the 81 children (34 male, 20 female; mean age 8y 2mo, SD 1.42, range 7–14y) completed assessments at 1, 2, or 3 months after receiving the DVD. Results Reductions (baseline to last assessment) in SSS Motor, SSS Impairment, and SLAS scores (all p<0.001) represented change ratios of –15%, –24%, and a –20%, respectively. Greatest relative treatment benefit was observed by younger children (ages 7–8y), and by one month after receipt of DVD, while a parent global assessment scale showed progressive improvement throughout the study. Interpretation An instructional DVD for parent-delivered behavioral therapy was a safe, effective intervention for primary CMS. PMID:27259464

  13. Inducible Nitric Oxide Inhibitors Block NMDA Antagonist-Stimulated Motoric Behaviors and Medial Prefrontal Cortical Glutamate Efflux

    PubMed Central

    Bergstrom, Hadley C.; Darvesh, Altaf S.; Berger, S. P.

    2015-01-01

    Nitric oxide (NO) plays a critical role in the motoric and glutamate releasing action of N-methyl-D-aspartate (NMDA)-antagonist stimulants. Earlier studies utilized neuronal nitric oxide synthase inhibitors (nNOS) for studying the neurobehavioral effects of non-competitive NMDA-antagonist stimulants such as dizocilpine (MK-801) and phencyclidine (PCP). This study explores the role of the inducible nitric oxide synthase inhibitors (iNOS) aminoguanidine (AG) and (-)-epigallocatechin-3-gallate (EGCG) in NMDA-antagonist induced motoric behavior and prefrontal cortical glutamate efflux. Adult male rats were administered a dose range of AG, EGCG, or vehicle prior to receiving NMDA antagonists MK-801, PCP, or a conventional psychostimulant (cocaine) and tested for motoric behavior in an open arena. Glutamate in the medial prefrontal cortex (mPFC) was measured using in vivo microdialysis after a combination of AG or EGCG prior to MK-801. Acute administration of AG or EGCG dose-dependently attenuated the locomotor and ataxic properties of MK-801 and PCP. Both AG and EGCG were unable to block the motoric effects of cocaine, indicating the acute pharmacologic action of AG and EGCG is specific to NMDA antagonism and not generalizable to all stimulant class drugs. AG and EGCG normalized MK-801-stimulated mPFC glutamate efflux. These data demonstrate that AG and EGCG attenuates NMDA antagonist-stimulated motoric behavior and cortical glutamate efflux. Our results suggest that EGCG-like polyphenol nutraceuticals (contained in “green tea” and chocolate) may be clinically useful in protecting against the adverse behavioral dissociative and cortical glutamate stimulating effects of NMDA antagonists. Medications that interfere with NMDA antagonists such as MK-801 and PCP have been proposed as treatments for schizophrenia. PMID:26696891

  14. Effects of Interventions Based in Behavior Analysis on Motor Skill Acquisition: A Meta-Analysis

    ERIC Educational Resources Information Center

    Alstot, Andrew E.; Kang, Minsoo; Alstot, Crystal D.

    2013-01-01

    Techniques based in applied behavior analysis (ABA) have been shown to be useful across a variety of settings to improve numerous behaviors. Specifically within physical activity settings, several studies have examined the effect of interventions based in ABA on a variety of motor skills, but the overall effects of these interventions are unknown.…

  15. SPEEDY babies: A putative new behavioral syndrome of unbalanced motor-speech development

    PubMed Central

    Haapanen, Marja-Leena; Aro, Tuomo; Isotalo, Elina

    2008-01-01

    Even though difficulties in motor development in children with speech and language disorders are widely known, hardly any attention is paid to the association between atypically rapidly occurring unassisted walking and delayed speech development. The four children described here presented with a developmental behavioral triad: 1) atypically speedy motor development, 2) impaired expressive speech, and 3) tongue carriage dysfunction resulting in related misarticulations. Those characteristics might be phenotypically or genetically clustered. These children didn’t have impaired cognition, neurological or mental disease, defective sense organs, craniofacial dysmorphology or susceptibility to upper respiratory infections, particularly recurrent otitis media. Attention should be paid on discordant and unbalanced achievement of developmental milestones. Present children are termed SPEEDY babies, where SPEEDY refers to rapid independent walking, SPEE and DY to dyspractic or dysfunctional speech development and lingual dysfunction resulting in linguoalveolar misarticulations. SPEEDY babies require health care that recognizes and respects their motor skills and supports their needs for motor activities and on the other hand include treatment for impaired speech. The parents may need advice and support with these children. PMID:19337462

  16. COMMUNICATION: On variability and use of rat primary motor cortex responses in behavioral task discrimination

    NASA Astrophysics Data System (ADS)

    Jensen, Winnie; Rousche, Patrick J.

    2006-03-01

    The success of a cortical motor neuroprosthetic system will rely on the system's ability to effectively execute complex motor tasks in a changing environment. Invasive, intra-cortical electrodes have been successfully used to predict joint movement and grip force of a robotic arm/hand with a non-human primate (Chapin J K, Moxon K A, Markowitz R S and Nicolelis M A L 1999 Real-time control of a robotic arm using simultaneously recorded neurons in the motor cortex Nat. Neurosci. 2 664-70). It is well known that cortical encoding occurs with a high degree of cortical plasticity and depends on both the functional and behavioral context. Questions on the expected robustness of future motor prosthesis systems therefore still remain. The objective of the present work was to study the effect of minor changes in functional movement strategies on the M1 encoding. We compared the M1 encoding in freely moving, non-constrained animals that performed two similar behavioral tasks with the same end-goal, and investigated if these behavioral tasks could be discriminated based on the M1 recordings. The rats depressed a response paddle either with a set of restrictive bars ('WB') or without the bars ('WOB') placed in front of the paddle. The WB task required changes in the motor strategy to complete the paddle press and resulted in highly stereotyped movements, whereas in the WOB task the movement strategy was not restricted. Neural population activity was recorded from 16-channel micro-wire arrays and data up to 200 ms before a paddle hit were analyzed off-line. The analysis showed a significant neural firing difference between the two similar WB and WOB tasks, and using principal component analysis it was possible to distinguish between the two tasks with a best classification at 76.6%. While the results are dependent upon a small, randomly sampled neural population, they indicate that information about similar behavioral tasks may be extracted from M1 based on relatively few

  17. Stimulation of subterritories of the subthalamic nucleus reveals its role in the integration of the emotional and motor aspects of behavior

    PubMed Central

    Mallet, Luc; Schüpbach, Michael; N'Diaye, Karim; Remy, Philippe; Bardinet, Eric; Czernecki, Virginie; Welter, Marie-Laure; Pelissolo, Antoine; Ruberg, Merle; Agid, Yves; Yelnik, Jérôme

    2007-01-01

    Two parkinsonian patients who experienced transient hypomanic states when the subthalamic nucleus (STN) was stimulated during postoperative adjustment of the electrical parameters for antiparkinsonian therapy agreed to have the mood disorder reproduced, in conjunction with motor, cognitive, and behavioral evaluations and concomitant functional neuroimaging. During the experiment, STN stimulation again induced a hypomanic state concomitant with activation of cortical and thalamic regions known to process limbic and associative information. This observation suggests that the STN plays a role in the control of a complex behavior that includes emotional as well as cognitive and motor components. The localization of the four contacts of the quadripolar electrode was determined precisely with an interactive brain atlas. The results showed that (i) the hypomanic state was caused only by stimulation through one contact localized in the anteromedial STN; (ii) both this contact and the contact immediately dorsal to it improved the parkinsonian motor state; (iii) the most dorsal and ventral contacts, located at the boundaries of the STN, neither induced the behavioral disorder nor improved motor performance. Detailed analysis of these data led us to consider a model in which the three functional modalities, emotional, cognitive, and motor, are not processed in a segregated manner but can be subtly combined in the small volume of the STN. This nucleus would thus serve as a nexus that integrates the motor, cognitive, and emotional components of behavior and might consequently be an effective target for the treatment of behavioral disorders that combine emotional, cognitive, and motor impairment. PMID:17556546

  18. Early Brain Damage and the Development of Motor Behavior in Children: Clues for Therapeutic Intervention?

    PubMed Central

    Hadders-Algra, Mijna

    2001-01-01

    The Neuronal Group Selection Theory (NGST) could offer new insights into the mechanisms directing motor disorders, such as cerebral palsy and developmental coordination disorder. According to NGST, normal motor development is characterized by two phases of variability. Variation is not at random but determined by criteria set by genetic information. Development starts with the phase of primary variability,during which variation in motor behavior is not geared to external conditions. At function-specific ages secondary variability starts, during which motor performance can be adapted to specific situations. In both forms, of variability, selection on the basis of afferent information plays a significant role. From the NGST point of view, children with pre- or perinatally acquired brain damage, such as children with cerebral palsy and part of the children with developmental coordination disorder, suffer from stereotyped motor behavior, produced by a limited repertoire or primary (sub)cortical neuronal networks. These children also have roblems in selecting the most efficient neuronal activity, due to deficits in the processing of sensory information. Therefore, NGST suggests that intervention in these children at early age should aim at an enlargement of the primary neuronal networks. With increasing age, the emphasis of intervention could shift to the provision of ample opportunities for active practice, which might form a compensation for the impaired selection. PMID:11530887

  19. Ketogenic diet restores aberrant cortical motor maps and excitation-to-inhibition imbalance in the BTBR mouse model of autism spectrum disorder.

    PubMed

    Smith, Jacklyn; Rho, Jong M; Teskey, G Campbell

    2016-05-01

    Autism spectrum disorder (ASD) is an increasingly prevalent neurodevelopmental disorder characterized by deficits in sociability and communication, and restricted and/or repetitive motor behaviors. Amongst the diverse hypotheses regarding the pathophysiology of ASD, one possibility is that there is increased neuronal excitation, leading to alterations in sensory processing, functional integration and behavior. Meanwhile, the high-fat, low-carbohydrate ketogenic diet (KD), traditionally used in the treatment of medically intractable epilepsy, has already been shown to reduce autistic behaviors in both humans and in rodent models of ASD. While the mechanisms underlying these effects remain unclear, we hypothesized that this dietary approach might shift the balance of excitation and inhibition towards more normal levels of inhibition. Using high-resolution intracortical microstimulation, we investigated basal sensorimotor excitation/inhibition in the BTBR T+Itpr(tf)/J (BTBR) mouse model of ASD and tested whether the KD restores the balance of excitation/inhibition. We found that BTBR mice had lower movement thresholds and larger motor maps indicative of higher excitation/inhibition compared to C57BL/6J (B6) controls, and that the KD reversed both these abnormalities. Collectively, our results afford a greater understanding of cortical excitation/inhibition balance in ASD and may help expedite the development of therapeutic approaches aimed at improving functional outcomes in this disorder. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Graphonomics and its contribution to the field of motor behavior: A position statement.

    PubMed

    Van Gemmert, Arend W A; Contreras-Vidal, Jose L

    2015-10-01

    The term graphonomics was conceived in the early 1980s; it defined a multidisciplinary emerging field focused on handwriting and drawing movements. Researchers in the field of graphonomics have made important contribution to the field of motor behavior by developing models aimed to conceptualize the production of fine motor movements using graphical tools. Although skeptics have argued that recent technological advancements would reduce the impact of graphonomic research, a shift of focus within in the field of graphonomics into fine motor tasks in general proves the resilience of the field. Moreover, it has been suggested that the use of fine motor movements due to technological advances has increased in importance in everyday life. It is concluded that the International Graphonomics Society can have a leading role in fostering collaborative multidisciplinary efforts and can help with the dissemination of findings contributing to the field of human movement sciences to a larger public. Copyright © 2015. Published by Elsevier B.V.

  1. Transitionality in addiction: A "temporal continuum" hypotheses involving the aberrant motivation, the hedonic dysregulation, and the aberrant learning.

    PubMed

    Patrono, Enrico; Gasbarri, Antonella; Tomaz, Carlos; Nishijo, Hisao

    2016-08-01

    Addiction is a chronic compulsion and relapsing disorder. It involves several brain areas and circuits, which encode vary functions such as reward, motivation, and memory. Drug addiction is defined as a "pathological pattern of use of a substance", characterized by the loss of control on drug-taking-related behaviors, the pursuance of those behaviors even in the presence of negative consequences, and a strong motivated activity to assume substances. Three different theories guide experimental research on drug addiction. Each of these theories consider singles features, such as an aberrant motivation, a hedonic dysregulation, and an aberrant habit learning as the main actor to explain the entire process of the addictive behaviors. The major goal of this study is to present a new hypotheses of transitionality from a controlled use to abuse of addictive substances trough the overview of the three different theories, considering all the single features of each single theory together on the same "temporal continuum" from use to abuse of addictive substances. Recently, it has been suggested that common neural systems may be activated by natural and pharmacological stimuli, raising the hypotheses that binge-eating disorders could be considered as addictive behaviors. The second goal of this study is to present evidences in order to highlight a possible psycho-bio-physiological superimposition between drug and "food addiction". Finally, interesting questions are brought up starting from last findings about a theoretical/psycho-bio-physiological superimposition between drug and "food addiction" and their possibly same transitionality along the same "temporal continuum" from use to abuse of addictive substances in order to investigate new therapeutic strategies based on new therapeutic strategies based on the individual moments characterizing the transition from the voluntary intake of substances to the maladaptive addictive behavior. Copyright © 2016. Published by Elsevier

  2. Automatic low-order aberration compensator for solid-state slab lasers

    NASA Astrophysics Data System (ADS)

    Yu, Xin; Dong, Lizhi; Lai, Boheng; Yang, Ping; Kong, Qingfeng; Yang, Kangjian; Liu, Yong; Tang, Guomao; Xu, Bing

    2016-09-01

    Slab geometry is a promising architecture for power scaling of solid-state lasers. By propagating the laser beams along zigzag path in the gain medium, the thermal effects can be well compensated. However, in the non-zigzag direction, the thermal effects are not compensated. Among the overall aberrations in the slab lasers, the major contributors are two low-order aberrations: astigmatism and defocus, which can range up to over 100 microns (peak to valley), leading to detracted beam quality. Another problem with slab lasers is that the output beams are generally in a rectangular aperture with high aspect ratio (normally 1:10), where square beams are favorable for many applications. In order to solve these problems, we propose an automatic low-order aberration compensation system. This system is composed of three lenses fixed on a motorized rail, one is a spherical lens and the others are cylindrical lenses. Astigmatism and defocus can be compensated by merely adjusting the distances between the lenses. Two wave-front sensors are employed in this compensation system, one is used for detecting the initial parameters of the beams, and the other one is used for detecting the remaining aberrations after correction. The adjustments of the three lenses are directly calculated based on beam parameters using ray tracing method. The initial size of the beam is 3.2mm by 26mm, and peak to valley(PV) value of the wave-front is 33.07λ(λ=1064nm). After correction, the dimension becomes 40mm by 40mm, and peak to valley (PV) value of the wave-front is less than 2 microns.

  3. A high performance sensorimotor beta rhythm-based brain computer interface associated with human natural motor behavior

    NASA Astrophysics Data System (ADS)

    Bai, Ou; Lin, Peter; Vorbach, Sherry; Floeter, Mary Kay; Hattori, Noriaki; Hallett, Mark

    2008-03-01

    To explore the reliability of a high performance brain-computer interface (BCI) using non-invasive EEG signals associated with human natural motor behavior does not require extensive training. We propose a new BCI method, where users perform either sustaining or stopping a motor task with time locking to a predefined time window. Nine healthy volunteers, one stroke survivor with right-sided hemiparesis and one patient with amyotrophic lateral sclerosis (ALS) participated in this study. Subjects did not receive BCI training before participating in this study. We investigated tasks of both physical movement and motor imagery. The surface Laplacian derivation was used for enhancing EEG spatial resolution. A model-free threshold setting method was used for the classification of motor intentions. The performance of the proposed BCI was validated by an online sequential binary-cursor-control game for two-dimensional cursor movement. Event-related desynchronization and synchronization were observed when subjects sustained or stopped either motor execution or motor imagery. Feature analysis showed that EEG beta band activity over sensorimotor area provided the largest discrimination. With simple model-free classification of beta band EEG activity from a single electrode (with surface Laplacian derivation), the online classifications of the EEG activity with motor execution/motor imagery were: >90%/~80% for six healthy volunteers, >80%/~80% for the stroke patient and ~90%/~80% for the ALS patient. The EEG activities of the other three healthy volunteers were not classifiable. The sensorimotor beta rhythm of EEG associated with human natural motor behavior can be used for a reliable and high performance BCI for both healthy subjects and patients with neurological disorders. Significance: The proposed new non-invasive BCI method highlights a practical BCI for clinical applications, where the user does not require extensive training.

  4. Modules in the brain stem and spinal cord underlying motor behaviors

    PubMed Central

    Cheung, Vincent C. K.; Bizzi, Emilio

    2011-01-01

    Previous studies using intact and spinalized animals have suggested that coordinated movements can be generated by appropriate combinations of muscle synergies controlled by the central nervous system (CNS). However, which CNS regions are responsible for expressing muscle synergies remains an open question. We address whether the brain stem and spinal cord are involved in expressing muscle synergies used for executing a range of natural movements. We analyzed the electromyographic (EMG) data recorded from frog leg muscles before and after transection at different levels of the neuraxis—rostral midbrain (brain stem preparations), rostral medulla (medullary preparations), and the spinal-medullary junction (spinal preparations). Brain stem frogs could jump, swim, kick, and step, while medullary frogs could perform only a partial repertoire of movements. In spinal frogs, cutaneous reflexes could be elicited. Systematic EMG analysis found two different synergy types: 1) synergies shared between pre- and posttransection states and 2) synergies specific to individual states. Almost all synergies found in natural movements persisted after transection at rostral midbrain or medulla but not at the spinal-medullary junction for swim and step. Some pretransection- and posttransection-specific synergies for a certain behavior appeared as shared synergies for other motor behaviors of the same animal. These results suggest that the medulla and spinal cord are sufficient for the expression of most muscle synergies in frog behaviors. Overall, this study provides further evidence supporting the idea that motor behaviors may be constructed by muscle synergies organized within the brain stem and spinal cord and activated by descending commands from supraspinal areas. PMID:21653716

  5. Housing conditions influence motor functions and exploratory behavior following focal damage of the rat brain.

    PubMed

    Gornicka-Pawlak, Elzbieta; Jabłońska, Anna; Chyliński, Andrzej; Domańska-Janik, Krystyna

    2009-01-01

    The present study investigated influence of housing conditions on motor functions recovery and exploratory behavior following ouabain focal brain lesion in the rat. During 30 days post-surgery period rats were housed individually in standard cages (IS) or in groups in enriched environment (EE) and behaviorally tested. The EE lesioned rats showed enhanced recovery from motor impairments in walking beam task, comparing with IS animals. Contrarily, in the open field IS rats (both lesioned and control) traveled a longer distance, showed less habituation and spent less time resting at the home base than the EE animals. Unlike the EE lesioned animals, the lesioned IS rats, presented a tendency to hyperactivity in postinjury period. Turning tendency was significantly affected by unilateral brain lesion only in the EE rats. We can conclude that housing conditions distinctly affected the rat's behavior in classical laboratory tests.

  6. Tio2-dopamine complex implanted unilaterally in the caudate nucleus improves motor activity and behavior function of rats with induced hemiparkinsonism.

    PubMed

    Vergara-Aragón, Patricia; Domínguez-Marrufo, Leonardo Eduardo; Ibarra-Guerrero, Patricia; Hernandez-Ramírez, Heidi; Hernández-Téllez, Beatriz; López-Martínez, Irma Elena; Sánchez-Cervantes, Ivonne; Santiago-Jacinto, Patricia; García-Macedo, Jorge Alberto; Valverde-Aguilar, Guadalupe; Santiago, Julio

    2011-01-01

    Parkinson's disease (PD) is characterized by malfunction of dopaminergic systems, and the current symptomatic treatment is to replace lost dopamine. For investigating mechanisms of pathogenesis and alternative treatments to compensate lack of dopamine (DA) activity in PD, the 6-hydroxydopamine (6-OHDA)-lesioned rat model of PD has been useful, these animals display apomorphine-induced contralateral rotational behavior, when they are examined after lesion. The purpose of this study was to assess Titania-dopamine (TiO2-DA) complexes implanted on the caudate nucleus for diminishing motor behavior alterations of the 6-OHDA rat model. Rats with 6-OHDA unilateral lesions received TiO2 alone or TiO2-DA implants, and were tested for open field (OF) gross motor crossing and rearing behaviors, and apomorphine-induced rotation (G) behavior. TiO2 complex have no effects on rearing OF and G behaviors, and a significant reducing effect on crossing motor behavior of normal rats compared to control non-treated rats throughout 56 days of observation. Interestingly, TiO2-DA treatment significant recovered motor crossing and rearing behaviors in 6-OHDA-lesioned rats, and diminished the G behaviors during 56 days of examination. Additionally, in the 6-OHDA-lesioned rats TiO2 treatment had a moderate recovering effect only on crossing behavior compared to lesioned non treated rats. Our results suggest that continuous release of dopamine in the caudate nucleus from TiO2-DA complex is capable of reversing gross motor deficits observed in the 6-OHDA-lesioned rat model of PD. Thistype of delivery system of DA represents a promising therapy for PD in humans.

  7. Examination of Post-stroke Alteration in Motor Unit Firing Behavior Using High Density Surface EMG Decomposition

    PubMed Central

    Li, Xiaoyan; Holobar, Aleš; Gazzoni, Marco; Merletti, Roberto; Rymer, William Z.; Zhou, Ping

    2014-01-01

    Recent advances in high density surface electromyogram (EMG) decomposition have made it a feasible task to discriminate single motor unit activity from surface EMG interference patterns, thus providing a noninvasive approach for examination of motor unit control properties. In the current study we applied high density surface EMG recording and decomposition techniques to assess motor unit firing behavior alterations post-stroke. Surface EMG signals were collected using a 64-channel 2-dimensional electrode array from the paretic and contralateral first dorsal interosseous (FDI) muscles of nine hemiparetic stroke subjects at different isometric discrete contraction levels between 2 N to 10 N with a 2 N increment step. Motor unit firing rates were extracted through decomposition of the high density surface EMG signals, and compared between paretic and contralateral muscles. Across the nine tested subjects, paretic FDI muscles showed decreased motor unit firing rates compared with contralateral muscles at different contraction levels. Regression analysis indicated a linear relation between the mean motor unit firing rate and the muscle contraction level for both paretic and contralateral muscles (p < 0.001), with the former demonstrating a lower increment rate (0.32 pulses per second (pps)/N) compared with the latter (0.67 pps/N). The coefficient of variation (CoV, averaged over the contraction levels) of the motor unit firing rates for the paretic muscles (0.21 ± 0.012) was significantly higher than for the contralateral muscles (0.17 ± 0.014) (p < 0.05). This study provides direct evidence of motor unit firing behavior alterations post-stroke using surface EMG, which can be an important factor contributing to hemiparetic muscle weakness. PMID:25389239

  8. Interaction of reinforcement schedules, a behavioral prosthesis, and work-related behavior in adults with mental retardation.

    PubMed

    Saunders, Richard R; McEntee, Julie E; Saunders, Muriel D

    2005-01-01

    The effects of variable-interval (VI) and fixed-ratio (FR) schedules of reinforcement for work-related behavior and an organizer for the work materials (behavioral prosthesis) were evaluated with 3 adults with severe or profound mental retardation. The participants had been recommended for study because of high rates of off-task and aberrant behavior in their daily vocational training programs. For 2 participants, VI and FR schedules resulted in the same outcome: more aberrant behavior than on-task and off-task behavior combined. The FR schedule nearly eliminated emission of aberrant and off-task behavior by the 3rd participant. Combining the behavioral prosthesis with FR reinforcement (FR+O) increased the proportion of time spent in on-task behavior by all participants under certain FR schedule parameters. Second-by-second analyses of the observation records revealed that FR schedules reduced off-task and aberrant behavior during work sequences (i.e., ratio runs), and FR+O led to a further reduction of these behaviors during postreinforcement pauses. Overall, the results show how organizer and schedule parameters can be adjusted to produce an optimized balance between productivity and reinforcement while undesirable behavior is minimized.

  9. Acute ethanol ingestion produces dose-dependent effects on motor behavior in the honey bee (Apis mellifera).

    PubMed

    Maze, Ian S; Wright, Geraldine A; Mustard, Julie A

    2006-01-01

    Ethanol consumption produces characteristic behavioral states in animals that include sedation, disorientation, and disruption of motor function. Using individual honey bees, we assessed the effects of ethanol ingestion on motor function via continuous observations of their behavior. Consumption of 1 M sucrose solutions containing a range of ethanol doses led to hemolymph ethanol levels of approximately 40-100 mM. Using ethanol doses in this range, we observed time and dose-dependent effects of ethanol on the percent of time our subjects spent walking, stopped, or upside down, and on the duration and frequency of bouts of behavior. The effects on grooming and flying behavior were more complex. Behavioral recovery from ethanol treatment was both time and ethanol dose dependent, occurring between 12 and 24 h post-ingestion for low doses and at 24-48 h for higher doses. Furthermore, the amount of ethanol measured in honey bee hemolymph appeared to correlate with recovery. We predict that the honey bee will prove to be an excellent model system for studying the influence of ethanol on the neural mechanisms underlying behavior.

  10. Stepper motor

    NASA Technical Reports Server (NTRS)

    Dekramer, Cornelis

    1994-01-01

    The purpose of this document is to describe the more commonly used permanent magnet stepper motors for spaceflight. It will discuss the mechanical and electrical aspects of the devices, their torque behavior, those parameters which need to be controlled and measured, and test methods to be employed. It will also discuss torque margins, compare these to the existing margin requirements, and determine the applicability of these requirements. Finally it will attempt to generate a set of requirements which will be used in any stepper motor procurement and will fully characterize the stepper motor behavior in a consistent and repeatable fashion.

  11. Fixational eye movement: a negligible source of dynamic aberration.

    PubMed

    Mecê, Pedro; Jarosz, Jessica; Conan, Jean-Marc; Petit, Cyril; Grieve, Kate; Paques, Michel; Meimon, Serge

    2018-02-01

    To evaluate the contribution of fixational eye movements to dynamic aberration, 50 healthy eyes were examined with an original custom-built Shack-Hartmann aberrometer, running at a temporal frequency of 236Hz, with 22 lenslets across a 5mm pupil, synchronized with a 236Hz pupil tracker. A comparison of the dynamic behavior of the first 21 Zernike modes (starting from defocus) with and without digital pupil stabilization, on a 3.4s sequence between blinks, showed that the contribution of fixational eye movements to dynamic aberration is negligible. Therefore we highlighted the fact that a pupil tracker coupled to an Adaptive Optics Ophthalmoscope is not essential to achieve diffraction-limited resolution.

  12. Marginal estimator for the aberrations of a space telescope by phase diversity

    NASA Astrophysics Data System (ADS)

    Blanc, Amandine; Mugnier, Laurent; Idier, Jérôme

    2017-11-01

    In this communication, we propose a novel method for estimating the aberrations of a space telescope from phase diversity data. The images recorded by such a telescope can be degraded by optical aberrations due to design, fabrication or misalignments. Phase diversity is a technique that allows the estimation of aberrations. The only estimator found in the relevant literature is based on a joint estimation of the aberrated phase and the observed object. We recall this approach and study the behavior of this joint estimator by means of simulations. We propose a novel marginal estimator of the sole phase. it is obtained by integrating the observed object out of the problem; indeed, this object is a nuisance parameter in our problem. This reduces drastically the number of unknown and provides better asymptotic properties. This estimator is implemented and its properties are validated by simulation. its performance is equal or even better than that of the joint estimator for the same computing cost.

  13. Assessment Position Affects Problem-Solving Behaviors in a Child With Motor Impairments.

    PubMed

    OʼGrady, Michael G; Dusing, Stacey C

    2016-01-01

    The purpose of this report was to examine problem-solving behaviors of a child with significant motor impairments in positions she could maintain independently, in supine and prone positions, as well as a position that required support, sitting. The child was a 22-month-old girl who could not sit independently and had limited independent mobility. Her problem-solving behaviors were assessed using the Early Problem Solving Indicator, while she was placed in supine or prone position, and again in manually supported sitting position. In manually supported sitting position, the subject demonstrated a higher frequency of problem-solving behaviors and her most developmentally advanced problem-solving behavior. Because a child's position may affect cognitive test results, position should be documented at the time of testing.

  14. Bimanual coupling paradigm as an effective tool to investigate productive behaviors in motor and body awareness impairments.

    PubMed

    Garbarini, Francesca; Pia, Lorenzo

    2013-11-05

    When humans move simultaneously both hands strong coupling effects arise and neither of the two hands is able to perform independent actions. It has been suggested that such motor constraints are tightly linked to action representation rather than to movement execution. Hence, bimanual tasks can represent an ideal experimental tool to investigate internal motor representations in those neurological conditions in which the movement of one hand is impaired. Indeed, any effect on the "moving" (healthy) hand would be caused by the constraints imposed by the ongoing motor program of the 'impaired' hand. Here, we review recent studies that successfully utilized the above-mentioned paradigms to investigate some types of productive motor behaviors in stroke patients. Specifically, bimanual tasks have been employed in left hemiplegic patients who report illusory movements of their contralesional limbs (anosognosia for hemiplegia). They have also been administered to patients affected by a specific monothematic delusion of body ownership, namely the belief that another person's arm and his/her voluntary action belong to them. In summary, the reviewed studies show that bimanual tasks are a simple and valuable experimental method apt to reveal information about the motor programs of a paralyzed limb. Therefore, it can be used to objectively examine the cognitive processes underpinning motor programming in patients with different delusions of motor behavior. Additionally, it also sheds light on the mechanisms subserving bimanual coordination in the intact brain suggesting that action representation might be sufficient to produce these effects.

  15. Brain–Computer Interface Training after Stroke Affects Patterns of Brain–Behavior Relationships in Corticospinal Motor Fibers

    PubMed Central

    Young, Brittany M.; Stamm, Julie M.; Song, Jie; Remsik, Alexander B.; Nair, Veena A.; Tyler, Mitchell E.; Edwards, Dorothy F.; Caldera, Kristin; Sattin, Justin A.; Williams, Justin C.; Prabhakaran, Vivek

    2016-01-01

    Background: Brain–computer interface (BCI) devices are being investigated for their application in stroke rehabilitation, but little is known about how structural changes in the motor system relate to behavioral measures with the use of these systems. Objective: This study examined relationships among diffusion tensor imaging (DTI)-derived metrics and with behavioral changes in stroke patients with and without BCI training. Methods: Stroke patients (n = 19) with upper extremity motor impairment were assessed using Stroke Impact Scale (SIS), Action Research Arm Test (ARAT), Nine-Hole Peg Test (9-HPT), and DTI scans. Ten subjects completed four assessments over a control period during which no training was administered. Seventeen subjects, including eight who completed the control period, completed four assessments over an experimental period during which subjects received interventional BCI training. Fractional anisotropy (FA) values were extracted from each corticospinal tract (CST) and transcallosal motor fibers for each scan. Results: No significant group by time interactions were identified at the group level in DTI or behavioral measures. During the control period, increases in contralesional CST FA and in asymmetric FA (aFA) correlated with poorer scores on SIS and 9-HPT. During the experimental period (with BCI training), increases in contralesional CST FA were correlated with improvements in 9-HPT while increases in aFA correlated with improvements in ARAT but with worsening 9-HPT performance; changes in transcallosal motor fibers positively correlated with those in the contralesional CST. All correlations p < 0.05 corrected. Conclusion: These findings suggest that the integrity of the contralesional CST may be used to track individual behavioral changes observed with BCI training after stroke. PMID:27695404

  16. Mask-induced aberration in EUV lithography

    NASA Astrophysics Data System (ADS)

    Nakajima, Yumi; Sato, Takashi; Inanami, Ryoichi; Nakasugi, Tetsuro; Higashiki, Tatsuhiko

    2009-04-01

    We estimated aberrations using Zernike sensitivity analysis. We found the difference of the tolerated aberration with line direction for illumination. The tolerated aberration of perpendicular line for illumination is much smaller than that of parallel line. We consider this difference to be attributable to the mask 3D effect. We call it mask-induced aberration. In the case of the perpendicular line for illumination, there was a difference in CD between right line and left line without aberration. In this report, we discuss the possibility of pattern formation in NA 0.25 generation EUV lithography tool. In perpendicular pattern for EUV light, the dominant part of aberration is mask-induced aberration. In EUV lithography, pattern correction based on the mask topography effect will be more important.

  17. A model for the transfer of perceptual-motor skill learning in human behaviors.

    PubMed

    Rosalie, Simon M; Müller, Sean

    2012-09-01

    This paper presents a preliminary model that outlines the mechanisms underlying the transfer of perceptual-motor skill learning in sport and everyday tasks. Perceptual-motor behavior is motivated by performance demands and evolves over time to increase the probability of success through adaptation. Performance demands at the time of an event create a unique transfer domain that specifies a range of potentially successful actions. Transfer comprises anticipatory subconscious and conscious mechanisms. The model also outlines how transfer occurs across a continuum, which depends on the individual's expertise and contextual variables occurring at the incidence of transfer

  18. Toll-like receptor 9 deficiency impacts sensory and motor behaviors.

    PubMed

    Khariv, Veronika; Pang, Kevin; Servatius, Richard J; David, Brian T; Goodus, Matthew T; Beck, Kevin D; Heary, Robert F; Elkabes, Stella

    2013-08-01

    Toll-like receptors (TLRs) mediate the induction of the innate immune system in response to pathogens, injury and disease. However, they also play non-immune roles and are expressed in the central nervous system (CNS) during prenatal and postnatal stages including adulthood. Little is known about their roles in the CNS in the absence of pathology. Several members of the TLR family have been implicated in the development of neural and cognitive function although the contribution of TLR9 to these processes has not been well defined. The current studies were undertaken to determine whether developmental TLR9 deficiency affects motor, sensory or cognitive functions. We report that TLR9 deficient (TLR9(-/-)) mice show a hyper-responsive sensory and motor phenotype compared to wild type (TLR9(+/+)) controls. This is indicated by hypersensitivity to thermal stimuli in the hot plate paw withdrawal test, enhanced motor-responsivity under anxious conditions in the open field test and greater sensorimotor reactivity in the acoustic startle response. Prepulse inhibition (PPI) of the acoustic startle response was also enhanced, which indicates abnormal sensorimotor gating. In addition, subtle, but significant, gait abnormalities were noted in the TLR9(-/-) mice on the horizontal balance beam test with higher foot slip numbers than TLR9(+/+) controls. In contrast, spatial learning and memory, assessed by the Morris water maze, was similar in the TLR9(-/-) and TLR9(+/+) mice. These findings support the notion that TLR9 is important for the appropriate development of sensory and motor behaviors. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Transport behaviors of locally fractional coupled Brownian motors with fluctuating interactions

    NASA Astrophysics Data System (ADS)

    Wang, Huiqi; Ni, Feixiang; Lin, Lifeng; Lv, Wangyong; Zhu, Hongqiang

    2018-09-01

    In some complex viscoelastic mediums, it is ubiquitous that absorbing and desorbing surrounding Brownian particles randomly occur in coupled systems. The conventional method is to model a variable-mass system driven by both multiplicative and additive noises. In this paper, an improved mathematical model is created based on generalized Langevin equations (GLE) to characterize the random interaction with locally fluctuating number of coupled particles in the elastically coupled factional Brownian motors (FBM). By the numerical simulations, the effect of fluctuating interactions on collective transport behaviors is investigated, and some abnormal phenomena, such as cooperative behaviors, stochastic resonance (SR) and anomalous transport, are observed in the regime of sub-diffusion.

  20. Psychiatric history and psychologic adjustment as risk factors for aberrant drug-related behavior among patients with chronic pain.

    PubMed

    Wasan, Ajay D; Butler, Stephen F; Budman, Simon H; Benoit, Christine; Fernandez, Kathrine; Jamison, Robert N

    2007-05-01

    To investigate the role of psychiatric history and psychologic adjustment on aberrant drug-related behavior among patients prescribed opioids for noncancer pain. Two hundred twenty-eight patients prescribed opioids for chronic pain were classified as either high or low on psychiatric morbidity on the basis of their responses on the psychiatric subscale of the Prescription Drug Use Questionnaire (PDUQ). They also completed the Brief Pain Inventory (BPI), Screener and Opioid Assessment for Pain Patients (SOAPP), and the Current Medication Misuse Measure (COMM). Patients were followed for 5 months and submitted a urine toxicology screen, and their treating physician completed the Prescription Opioid Therapy Questionnaire (POTQ). On the basis of the results from the SOAPP, COMM, POTQ, and urine screens, patients were classified as positive or negative on the Drug Misuse Index (DMI). One hundred and three (N=103) of the patients (45%) were classified in the low psychiatric group (Low Psych) whereas 55% (N=125) were classified in the high psychiatric morbidity group (High Psych). High Psych patients were significantly younger than Low Psych patients and had been taking opioids longer (P<0.05). The High Psych group showed significantly higher SOAPP and COMM scores than the Low Psych patients (P<0.001), had a greater frequency of abnormal urine toxicology screens (P<0.01), and significantly higher scores on the DMI (P<0.001). A consistent association was found between psychiatric morbidity and prescription opioid misuse in chronic pain patients. Psychiatric factors, such as a history of mood disorder, psychologic problems, and psychosocial stressors, may place patients at risk for misuse of prescription opioids. Future studies to elucidate the risk of medication misuse and aberrant drug behavior among this patient population are needed.

  1. Vibrissa motor cortex activity suppresses contralateral whisking behavior.

    PubMed

    Ebbesen, Christian Laut; Doron, Guy; Lenschow, Constanze; Brecht, Michael

    2017-01-01

    Anatomical, stimulation and lesion data implicate vibrissa motor cortex in whisker motor control. Work on motor cortex has focused on movement generation, but correlations between vibrissa motor cortex activity and whisking are weak. The exact role of vibrissa motor cortex remains unknown. We recorded vibrissa motor cortex neurons during various forms of vibrissal touch, which were invariably associated with whisker protraction and movement. Free whisking, object palpation and social touch all resulted in decreased cortical activity. To understand this activity decrease, we performed juxtacellular recordings, nanostimulation and in vivo whole-cell recordings. Social touch resulted in decreased spiking activity, decreased cell excitability and membrane hyperpolarization. Activation of vibrissa motor cortex by intracortical microstimulation elicited whisker retraction, as if to abort vibrissal touch. Various vibrissa motor cortex inactivation protocols resulted in contralateral protraction and increased whisker movements. These data collectively point to movement suppression as a prime function of vibrissa motor cortex activity.

  2. Co-occurring motor, language and emotional-behavioral problems in children 3-6 years of age.

    PubMed

    King-Dowling, Sara; Missiuna, Cheryl; Rodriguez, M Christine; Greenway, Matt; Cairney, John

    2015-02-01

    Developmental Coordination Disorder (DCD) has been shown to co-occur with behavioral and language problems in school-aged children, but little is known as to when these problems begin to emerge, or if they are inherent in children with DCD. The purpose of this study was to determine if deficits in language and emotional-behavioral problems are apparent in preschool-aged children with movement difficulties. Two hundred and fourteen children (mean age 4years 11months, SD 9.8months, 103 male) performed the Movement Assessment Battery for Children 2nd Edition (MABC-2). Children falling at or below the 16th percentile were classified as being at risk for movement difficulties (MD risk). Auditory comprehension and expressive communication were examined using the Preschool Language Scales 4th Edition (PLS-4). Parent-reported emotional and behavioral problems were assessed using the Child Behavior Checklist (CBCL). Preschool children with diminished motor coordination (n=37) were found to have lower language scores, higher externalizing behaviors in the form of increased aggression, as well as increased withdrawn and other behavior symptoms compared with their typically developing peers. Motor coordination, language and emotional-behavioral difficulties tend to co-occur in young children aged 3-6years. These results highlight the need for early intervention. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Camera processing with chromatic aberration.

    PubMed

    Korneliussen, Jan Tore; Hirakawa, Keigo

    2014-10-01

    Since the refractive index of materials commonly used for lens depends on the wavelengths of light, practical camera optics fail to converge light to a single point on an image plane. Known as chromatic aberration, this phenomenon distorts image details by introducing magnification error, defocus blur, and color fringes. Though achromatic and apochromatic lens designs reduce chromatic aberration to a degree, they are complex and expensive and they do not offer a perfect correction. In this paper, we propose a new postcapture processing scheme designed to overcome these problems computationally. Specifically, the proposed solution is comprised of chromatic aberration-tolerant demosaicking algorithm and post-demosaicking chromatic aberration correction. Experiments with simulated and real sensor data verify that the chromatic aberration is effectively corrected.

  4. Acute ethanol ingestion produces dose-dependent effects on motor behavior in the honey bee (Apis mellifera)

    PubMed Central

    Maze, Ian S.; Wright, Geraldine A.; Mustard, Julie A.

    2006-01-01

    Ethanol consumption produces characteristic behavioral states in animals that include sedation, disorientation, and disruption of motor function. Using individual honey bees, we assessed the effects of ethanol ingestion on motor function via continuous observations of their behavior. Consumption of 1 M sucrose solutions containing a range of ethanol doses lead to hemolymph ethanol levels of approximately 40 to 100 mM. Using ethanol doses in this range, we observed time and dose-dependent effects of ethanol on the percent of time our subjects spent walking, stopped, or upside down, and on the duration and frequency of bouts of behavior. The effects on grooming and flying behavior were more complex. Behavioral recovery from ethanol treatment was both time and ethanol dose dependent, occurring between 12 and 24 hr post-ingestion for low doses and at 24 to 48 hours for higher doses. Furthermore, the amount of ethanol measured in honey bee hemolymph appeared to correlate with recovery. We predict that the honey bee will prove to be an excellent model system for studying the influence of ethanol on the neural mechanisms underlying behavior. PMID:17070538

  5. Psychometric Properties of the "Aberrant Behavior Checklist," the "Anxiety, Depression and Mood Scale," the "Assessment of Dual Diagnosis" and the "Social Performance Survey Schedule" in Adults with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Rojahn, Johannes; Rowe, Ellen W.; Kasdan, Shana; Moore, Linda; van Ingen, Daniel J.

    2011-01-01

    Progress in clinical research and in empirically supported interventions in the area of psychopathology in intellectual disabilities (ID) depends on high-quality assessment instruments. To this end, psychometric properties of four instruments were examined: the "Aberrant Behavior Checklist" (ABC), the "Assessment of Dual…

  6. Polyphasic Temporal Behavior of Finger-Tapping Performance: A Measure of Motor Skills and Fatigue.

    PubMed

    Aydin, Leyla; Kiziltan, Erhan; Gundogan, Nimet Unay

    2016-01-01

    Successive voluntary motor movement involves a number of physiological mechanisms and may reflect motor skill development and neuromuscular fatigue. In this study, the temporal behavior of finger tapping was investigated in relation to motor skills and fatigue by using a long-term computer-based test. The finger-tapping performances of 29 healthy male volunteers were analyzed using linear and nonlinear regression models established for inter-tapping interval. The results suggest that finger-tapping performance exhibits a polyphasic nature, and has several characteristic time points, which may be directly related to muscle dynamics and energy consumption. In conclusion, we believe that future studies evaluating the polyphasic nature of the maximal voluntary movement will lead to the definition of objective scales that can be used in the follow up of some neuromuscular diseases, as well as, the determination of motor skills, individual ability, and peripheral fatigue through the use of a low cost, easy-to-use computer-based finger-tapping test.

  7. Passive or simulated displacement of one arm (but not its mirror reflection) modulates the involuntary motor behavior of the other arm.

    PubMed

    Brun, C; Metral, M; Chancel, M; Kavounoudias, A; Luyat, M; Guerraz, M

    2015-01-29

    Recent studies of both healthy and patient populations have cast doubt on the mirror paradigm's beneficial effect on motor behavior. Indeed, the voluntary arm displacement that accompanies reflection in the mirror may be the determining factor in terms of the motor behavior of the contralateral arm. The objective of the present study was to assess the respective effects of mirror reflection and arm displacement (whether real or simulated) on involuntary motor behavior of the contralateral arm following sustained, isometric contraction (Kohnstamm phenomenon). Our results revealed that (i) passive displacement of one arm (displacement of the left arm via a motorized manipulandum moving at 4°/s) influenced the velocity of the Kohnstamm phenomenon (forearm flexion occurring shortly after the cessation of muscle contraction) in the contralateral arm and (ii) mirror vision had no effect. Indeed, the velocity of the Kohnstamm phenomenon tended to be adjusted to match the velocity of the passive displacement of the other arm. In a second experiment, arm displacement was simulated by vibrating the triceps at 25, 50 or 75 Hz. Results showed that the velocity of the Kohnstamm phenomenon in one arm increased with the vibration frequency applied to the other arm. Our results revealed the occurrence of bimanual coupling because involuntary displacement of one arm was regulated by muscle-related information generated by the actual or simulated displacement of the other arm. In line with the literature data on voluntary motor behavior, our study failed to evidence an additional impact of mirror vision on involuntary motor behavior. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

  8. An Item Response Analysis of the Motor and Behavioral Subscales of the Unified Huntington's Disease Rating Scale in Huntington Disease Gene Expansion Carriers

    PubMed Central

    Vaccarino, Anthony L.; Anderson, Karen; Borowsky, Beth; Duff, Kevin; Giuliano, Joseph; Guttman, Mark; Ho, Aileen K.; Orth, Michael; Paulsen, Jane S.; Sills, Terrence; van Kammen, Daniel P.; Evans, Kenneth R.

    2011-01-01

    Although the Unified Huntington's Disease Rating Scale (UHDRS) is widely used in the assessment of Huntington disease (HD), the ability of individual items to discriminate individual differences in motor or behavioral manifestations has not been extensively studied in HD gene expansion carriers without a motor-defined clinical diagnosis (i.e., prodromal-HD or prHD). To elucidate the relationship between scores on individual motor and behavioral UHDRS items and total score for each subscale, a non-parametric item response analysis was performed on retrospective data from two multicentre, longitudinal studies. Motor and Behavioral assessments were supplied for 737 prHD individuals with data from 2114 visits (PREDICT-HD) and 686 HD individuals with data from 1482 visits (REGISTRY). Option characteristic curves were generated for UHDRS subscale items in relation to their subscale score. In prHD, overall severity of motor signs was low and participants had scores of 2 or above on very few items. In HD, motor items that assessed ocular pursuit, saccade initiation, finger tapping, tandem walking, and to a lesser extent saccade velocity, dysarthia, tongue protrusion, pronation/supination, Luria, bradykinesia, choreas, gait and balance on the retropulsion test were found to discriminate individual differences across a broad range of motor severity. In prHD, depressed mood, anxiety, and irritable behavior demonstrated good discriminative properties. In HD, depressed mood demonstrated a good relationship with the overall behavioral score. These data suggest that at least some UHDRS items appear to have utility across a broad range of severity, although many items demonstrate problematic features. PMID:21370269

  9. An item response analysis of the motor and behavioral subscales of the unified Huntington's disease rating scale in huntington disease gene expansion carriers.

    PubMed

    Vaccarino, Anthony L; Anderson, Karen; Borowsky, Beth; Duff, Kevin; Giuliano, Joseph; Guttman, Mark; Ho, Aileen K; Orth, Michael; Paulsen, Jane S; Sills, Terrence; van Kammen, Daniel P; Evans, Kenneth R

    2011-04-01

    Although the Unified Huntington's Disease Rating Scale (UHDRS) is widely used in the assessment of Huntington disease (HD), the ability of individual items to discriminate individual differences in motor or behavioral manifestations has not been extensively studied in HD gene expansion carriers without a motor-defined clinical diagnosis (ie, prodromal-HD or prHD). To elucidate the relationship between scores on individual motor and behavioral UHDRS items and total score for each subscale, a nonparametric item response analysis was performed on retrospective data from 2 multicenter longitudinal studies. Motor and behavioral assessments were supplied for 737 prHD individuals with data from 2114 visits (PREDICT-HD) and 686 HD individuals with data from 1482 visits (REGISTRY). Option characteristic curves were generated for UHDRS subscale items in relation to their subscale score. In prHD, overall severity of motor signs was low, and participants had scores of 2 or above on very few items. In HD, motor items that assessed ocular pursuit, saccade initiation, finger tapping, tandem walking, and to a lesser extent, saccade velocity, dysarthria, tongue protrusion, pronation/supination, Luria, bradykinesia, choreas, gait, and balance on the retropulsion test were found to discriminate individual differences across a broad range of motor severity. In prHD, depressed mood, anxiety, and irritable behavior demonstrated good discriminative properties. In HD, depressed mood demonstrated a good relationship with the overall behavioral score. These data suggest that at least some UHDRS items appear to have utility across a broad range of severity, although many items demonstrate problematic features. Copyright © 2011 Movement Disorder Society.

  10. Adaptive optics full-field OCT: a resolution almost insensitive to aberrations (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Xiao, Peng; Fink, Mathias; Boccara, A. Claude

    2016-03-01

    A Full-Field OCT (FFOCT) setup coupled to a compact transmissive liquid crystal spatial light modulator (LCSLM) is used to induce or correct aberrations and simulate eye examinations. To reduce the system complexity, strict pupil conjugation was abandoned. During our work on quantifying the effect of geometrical aberrations on FFOCT images, we found that the image resolution is almost insensitive to aberrations. Indeed if the object channel PSF is distorted, its interference with the reference channel conserves the main feature of an unperturbed PSF with only a reduction of the signal level. This unique behavior is specific to the use of a spatially incoherent illumination. Based on this, the FFOCT image intensity was used as the metric for our wavefront sensorless correction. Aberration correction was first conducted on an USAF resolution target with the LSCLM as both aberration generator and corrector. A random aberration mask was induced, and the low-order Zernike Modes were corrected sequentially according to the intensity metric function optimization. A Ficus leaf and a fixed mouse brain tissue slice were also imaged to demonstrate the correction of sample self-induced wavefront distortions. After optimization, more structured information appears for the leaf imaging. And the high-signal fiber-like myelin fiber structures were resolved much more clearly after the whole correction process for mouse brain imaging. Our experiment shows the potential of this compact AO-FFOCT system for aberration correction imaging. This preliminary approach that simulates eyes aberrations correction also opens the path to a simple implementation of FFOCT adaptive optics for retinal examinations.

  11. Differentiating children with attention-deficit/hyperactivity disorder, conduct disorder, learning disabilities and autistic spectrum disorders by means of their motor behavior characteristics.

    PubMed

    Efstratopoulou, Maria; Janssen, Rianne; Simons, Johan

    2012-01-01

    The study was designed to investigate the discriminant validity of the Motor Behavior Checklist (MBC) for distinguishing four group of children independently classified with Attention-Deficit/Hyperactivity Disorder, (ADHD; N=22), Conduct Disorder (CD; N=17), Learning Disabilities (LD; N=24) and Autistic Spectrum Disorders (ASD; N=20). Physical education teachers used the MBC for children to rate their pupils based on their motor related behaviors. A multivariate analysis revealed significant differences among the groups on different problem scales. The results indicated that the MBC for children may be effective in discriminating children with similar disruptive behaviors (e.g., ADHD, CD) and autistic disorders, based on their motor behavior characteristics, but not children with Learning Disabilities (LD), when used by physical education teachers in school settings. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Behavioral and neural effects of congruency of visual feedback during short-term motor learning.

    PubMed

    Ossmy, Ori; Mukamel, Roy

    2018-05-15

    Visual feedback can facilitate or interfere with movement execution. Here, we describe behavioral and neural mechanisms by which the congruency of visual feedback during physical practice of a motor skill modulates subsequent performance gains. 18 healthy subjects learned to execute rapid sequences of right hand finger movements during fMRI scans either with or without visual feedback. Feedback consisted of a real-time, movement-based display of virtual hands that was either congruent (right virtual hand movement), or incongruent (left virtual hand movement yoked to the executing right hand). At the group level, right hand performance gains following training with congruent visual feedback were significantly higher relative to training without visual feedback. Conversely, performance gains following training with incongruent visual feedback were significantly lower. Interestingly, across individual subjects these opposite effects correlated. Activation in the Supplementary Motor Area (SMA) during training corresponded to individual differences in subsequent performance gains. Furthermore, functional coupling of SMA with visual cortices predicted individual differences in behavior. Our results demonstrate that some individuals are more sensitive than others to congruency of visual feedback during short-term motor learning and that neural activation in SMA correlates with such inter-individual differences. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Tris (2-butoxyethyl) phosphate affects motor behavior and axonal growth in zebrafish (Danio rerio) larvae.

    PubMed

    Jiang, Fan; Liu, Jue; Zeng, Xinyue; Yu, Liqin; Liu, Chunsheng; Wang, Jianghua

    2018-05-01

    Tris (2-butoxyethyl) phosphate (TBOEP) is an environmental contaminant that poses serious risks to aquatic organisms and their associated ecosystem. Recently, the reproductive and developmental toxicology of TBOEP has been reported. However, fewer studies have assessed the neurotoxic effects in zebrafish (Danio rerio) larvae. In this study, zebrafish embryos were subjected to waterborne exposure of TBOEP at 0, 50, 500, 1500 and 2500 μg/L from 2 to 144-h post-fertilization (hpf). Behavioral measurements showed that TBOEP exposure reduced embryonic spontaneous movement and decreased swimming speed of larvae in response to dark stimulation. In accordance with these motor effects, TBOEP treatment reduced neuron-specific GFP expression in transgenic Tg (HuC-GFP) zebrafish larvae and inhibited the growth of secondary motoneurons, as well as decreased expression of marker genes related to central nervous system development in TBOEP treated group. Furthermore, increased concentrations of reactive oxygen species (ROS) and malondialdehyde (MDA), as well as reduction of SOD activity were detected in TBOEP exposure group. The present results showed that the alteration in motor neuron and oxidative stress could together lead to the motor behavior alterations induced by TBOEP. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. [Motor behavior of human fetuses during the second trimester of gestation: a longitudinal ultrasound study].

    PubMed

    Reynoso, C; Crespo-Eguílaz, N; Alcázar, J L; Narbona, J

    2015-03-01

    The aim of this research is to contribute to knowledge of the normal spontaneous motor behavior of the human fetus during the second trimester of pregnancy. This study focuses on five patterns of spontaneous fetal movement: startle (S), axo-rhizomelic rhythmia (ARR), axial stretching (AS), general movement (GM), and diaphragmatic contraction (DC). A cohort of 13 subjects was followed up using 2D obstetrical ultrasound images at 12, 16, 20, and 24 weeks of gestation. As inclusion criteria, neonatal neurological examination and general movements after eutocic delivery at term were normal in all of the subjects, and their neuromotor and cognitive development until the end of pre-school age were also normal. All these five motor patterns are present at the beginning of the 2(nd) gestational trimester, but their quantitative and qualitative traits are diverse according to gestational ages. The phasic, isolated or rhythmically repeated movements, S and ARR, are prominent at 12 and 16 weeks of gestation, and then their presence gradually diminishes. By contrast, tonic and complex AS and GM movements increase their presence and quality at 20 and 24 weeks. RAR constitute a particular periodic motor pattern not described in previous literature. Moreover, the incidence of DC is progressive throughout the trimester, in clusters of 2-6 arrhythmic and irregular beats. Fetal heart rate increases during fetal motor active periods. All five normal behavioral patterns observed in the ultrasounds reflect the progressive tuning of motor generators in human nervous system during mid-pregnancy. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

  15. Enduring effects of post-weaning rearing condition on depressive- and anxiety-like behaviors and motor activity in male rats.

    PubMed

    Mosaferi, Belal; Babri, Shirin; Ebrahimi, Hadi; Mohaddes, Gisou

    2015-04-01

    Environmental manipulation at early critical periods could have long-lasting effects. In spite of the great interest in the biological effects of the environmental condition so far, its long-lasting effects are less documented. This study looks at the enduring effects of rearing condition on tasks that measure affective responses and exploratory behavior in male Wistar rats. The animals were reared from weaning to adulthood in an enriched environment, standard laboratory condition, or isolated condition. Then, all rats were housed in standard laboratory cages to provide a common environment, and successively exposed to different tests between 0 and 11 weeks post-manipulation. The open field test indicated a more efficient exploratory behavior in the enriched group, and an enhanced spontaneous motor activity in both standard and isolated groups. In addition, rats reared in standard condition showed heightened motor activity in forced swimming test and elevated plus maze. Forced swimming test showed an antidepressive-like effect in the enriched environment group by increased climbing behavior. In respect to the anxiety behavior, environmental enrichment improved threat detection ability. It is concluded that rearing condition from weaning to adulthood has important and long-lasting effects on depressive- and anxiety-like and exploratory behaviors as well as motor activity. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. The Small GTP-Binding Protein Rhes Influences Nigrostriatal-Dependent Motor Behavior During Aging.

    PubMed

    Pinna, Annalisa; Napolitano, Francesco; Pelosi, Barbara; Di Maio, Anna; Wardas, Jadwiga; Casu, Maria Antonietta; Costa, Giulia; Migliarini, Sara; Calabresi, Paolo; Pasqualetti, Massimo; Morelli, Micaela; Usiello, Alessandro

    2016-04-01

    Here we aimed to evaluate: (1) Rhes mRNA expression in mouse midbrain, (2) the effect of Rhes deletion on the number of dopamine neurons, (3) nigrostriatal-sensitive behavior during aging in knockout mice. Radioactive in situ hybridization was assessed in adult mice. The beam-walking test was executed in 3-, 6- and 12-month-old mice. Immunohistochemistry of midbrain tyrosine hydroxylase (TH)-positive neurons was performed in 6- and 12-month-old mice. Rhes mRNA is expressed in TH-positive neurons of SNpc and the ventral tegmental area. Moreover, lack of Rhes leads to roughly a 20% loss of nigral TH-positive neurons in both 6- and 12-month-old mutants, when compared with their age-matched controls. Finally, lack of Rhes triggers subtle alterations in motor performance and coordination during aging. Our findings indicate a fine-tuning role of Rhes in regulating the number of TH-positive neurons of the substantia nigra and nigrostriatal-sensitive motor behavior during aging. © 2016 International Parkinson and Movement Disorder Society.

  17. Motor control is decision-making.

    PubMed

    Wolpert, Daniel M; Landy, Michael S

    2012-12-01

    Motor behavior may be viewed as a problem of maximizing the utility of movement outcome in the face of sensory, motor and task uncertainty. Viewed in this way, and allowing for the availability of prior knowledge in the form of a probability distribution over possible states of the world, the choice of a movement plan and strategy for motor control becomes an application of statistical decision theory. This point of view has proven successful in recent years in accounting for movement under risk, inferring the loss function used in motor tasks, and explaining motor behavior in a wide variety of circumstances. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Proteostasis and Diseases of the Motor Unit.

    PubMed

    Rinaldi, Carlo; Mäger, Imre; Wood, Matthew J

    2016-01-01

    The accumulation in neurons of aberrant protein species, the pathological hallmark of many neurodegenerative diseases, results from a global impairment of key cellular processes governing protein synthesis/degradation and repair mechanisms, also known as the proteostasis network (PN). The growing number of connections between dysfunction of this intricate network of pathways and diseases of the motor unit, where both motor neurons and muscle are primarily affected, has provided momentum to investigate the muscle- and motor neuron-specific response to physiological and pathological stressors and to explore the therapeutic opportunities that manipulation of this process may offer. Furthermore, these diseases offer an unparalleled opportunity to deepen our understanding of the molecular mechanisms behind the intertissue communication and transfer of signals of proteostasis. The most compelling aspect of these investigations is their immediate potential for therapeutic impact: targeting muscle to stem degeneration of the motor unit would represent a dramatic paradigm therapeutic shift for treating these devastating diseases. Here we will review the current state of the art of the research on the alterations of the PN in diseases of the motor unit and its potential to result in effective treatments for these devastating neuromuscular disorders.

  19. Comparison of psychopathological dimensions between major depressive disorder and schizophrenia spectrum disorders focusing on language, affectivity and motor behavior.

    PubMed

    Steinau, Sarah; Stegmayer, Katharina; Lang, Fabian U; Jäger, Markus; Strik, Werner; Walther, Sebastian

    2017-04-01

    This study tested whether patients with major depressive disorder (MDD) and schizophrenia spectrum disorders would differ in three dimensions of psychopathology (language, affectivity and motor behavior) as assessed by the Bern Psychopathology Scale (BPS) in a cohort of 58 patients with MDD and 146 patients with schizophrenia spectrum disorders. The overall estimation of severity of each of the three dimensions was rated on a seven-point Likert scale from severely inhibited to severely disinhibited. Here, more than half of the patients endorsed ratings that showed normal or mildly (dis-)inhibited behavior. At group level more pronounced negative ratings of affect were seen in MDD. Group comparisons of the severity ratings on language or motor behavior yielded no differences between schizophrenia spectrum disorders and MDD. At the individuals' levels, extreme ratings in the language and motor dimensions were more frequent in schizophrenia spectrum disorders and in the affectivity dimension more frequent in MDD. Shared psychopathological features could be seen across diagnoses, supporting a dimensional approach to psychopathology in endogenous psychoses. However, the groups differ in the severity of affect ratings as well as in the distribution of language, affectivity and motor ratings with more variance among the group of schizophrenia spectrum disorders. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  20. Correlations between corneal and total wavefront aberrations

    NASA Astrophysics Data System (ADS)

    Mrochen, Michael; Jankov, Mirko; Bueeler, Michael; Seiler, Theo

    2002-06-01

    Purpose: Corneal topography data expressed as corneal aberrations are frequently used to report corneal laser surgery results. However, the optical image quality at the retina depends on all optical elements of the eye such as the human lens. Thus, the aim of this study was to investigate the correlations between the corneal and total wavefront aberrations and to discuss the importance of corneal aberrations for representing corneal laser surgery results. Methods: Thirty three eyes of 22 myopic subjects were measured with a corneal topography system and a Tschernig-type wavefront analyzer after the pupils were dilated to at least 6 mm in diameter. All measurements were centered with respect to the line of sight. Corneal and total wavefront aberrations were calculated up to the 6th Zernike order in the same reference plane. Results: Statistically significant correlations (p < 0.05) between the corneal and total wavefront aberrations were found for the astigmatism (C3,C5) and all 3rd Zernike order coefficients such as coma (C7,C8). No statistically significant correlations were found for all 4th to 6th order Zernike coefficients except for the 5th order horizontal coma C18 (p equals 0.003). On average, all Zernike coefficients for the corneal aberrations were found to be larger compared to Zernike coefficients for the total wavefront aberrations. Conclusions: Corneal aberrations are only of limited use for representing the optical quality of the human eye after corneal laser surgery. This is due to the lack of correlation between corneal and total wavefront aberrations in most of the higher order aberrations. Besides this, the data present in this study yield towards an aberration balancing between corneal aberrations and the optical elements within the eye that reduces the aberration from the cornea by a certain degree. Consequently, ideal customized ablations have to take both, corneal and total wavefront aberrations, into consideration.

  1. Monkey motor stimulation and altered social behavior during chronic methadone administration.

    PubMed

    Crowley, T J; Hydinger, M; Stynes, A J; Feiger, A

    1975-08-21

    To assess the effects of chronic methadone administration on locomotor, social, and eating behavior od drug-native individuals under circumstances approximating those of methadone "maintenance" clinics, we gave single, daily oral doses of methadone to 5 Macaca radiata monkeys living in a social group. We obtained motor activity counts automatically during 6 weeks of baseline, 10 weeks of drug administration, and 3 weeks of post-drug abstinence. Social behaviors of association, dominance, submission, and sexuality were counted 5 days per week, and animal weights, food eaten and food-reinforced work were recorded. Plasma methadone levels were near those achieved in mechadone clincs. Methadone produced mixed stimulation and sedation in the daytime, with stimulation predominating for 4 hrs following administration. At night the subjects moved less while taking the drug. Associative behaviors were reduced by methadone, but dominance, submission, and sexual behaviors were not altered. The monkeys ate less while taking the drug, losing weight and working less for food. In these primates methadone had significant stimulant properties, impaired important social behaviors, and reduced the potency of food as a reinforcer of work. The results are compared with methadone's effects upon humans.

  2. A SMN-Dependent U12 Splicing Event Essential for Motor Circuit Function

    PubMed Central

    Lotti, Francesco; Imlach, Wendy L.; Saieva, Luciano; Beck, Erin S.; Hao, Le T.; Li, Darrick K.; Jiao, Wei; Mentis, George Z.; Beattie, Christine E.; McCabe, Brian D.; Pellizzoni, Livio

    2012-01-01

    SUMMARY Spinal muscular atrophy (SMA) is a motor neuron disease caused by deficiency of the ubiquitous survival motor neuron (SMN) protein. To define the mechanisms of selective neuronal dysfunction in SMA, we investigated the role of SMN-dependent U12 splicing events in the regulation of motor circuit activity. We show that SMN deficiency perturbs splicing and decreases the expression of a subset of U12 intron-containing genes in mammalian cells and Drosophila larvae. Analysis of these SMN target genes identifies Stasimon as a novel protein required for motor circuit function. Restoration of Stasimon expression in the motor circuit corrects defects in neuromuscular junction transmission and muscle growth in Drosophila SMN mutants and aberrant motor neuron development in SMN-deficient zebrafish. These findings directly link defective splicing of critical neuronal genes induced by SMN deficiency to motor circuit dysfunction, establishing a molecular framework for the selective pathology of SMA. PMID:23063131

  3. Motor cortex inhibition

    PubMed Central

    Isaacs, K.M.; Augusta, M.; MacNeil, L.K.; Mostofsky, S.H.

    2011-01-01

    Objective: Attention-deficit/hyperactivity disorder (ADHD) is a childhood-onset behavioral diagnosis in which children often fail to meet age norms in development of motor control, particularly timed repetitive and sequential movements, motor overflow, and balance. The neural substrate of this motor delay may include mechanisms of synaptic inhibition in or adjacent to the motor cortex. The primary objective of this study was to determine whether transcranial magnetic stimulation (TMS)–evoked measures, particularly short interval cortical inhibition (SICI), in motor cortex correlate with the presence and severity of ADHD in childhood as well as with commonly observed delays in motor control. Methods: In this case-control study, behavioral ratings, motor skills, and motor cortex physiology were evaluated in 49 children with ADHD (mean age 10.6 years, 30 boys) and 49 typically developing children (mean age 10.5 years, 30 boys), all right-handed, aged 8–12 years. Motor skills were evaluated with the Physical and Neurological Examination for Subtle Signs (PANESS) and the Motor Assessment Battery for Children version 2. SICI and other physiologic measures were obtained using TMS in the left motor cortex. Results: In children with ADHD, mean SICI was reduced by 40% (p < 0.0001) and less SICI correlated with higher ADHD severity (r = −0.52; p = 0.002). Mean PANESS motor development scores were 59% worse in children with ADHD (p < 0.0001). Worse PANESS scores correlated modestly with less SICI (r = −.30; p = 0.01). Conclusion: Reduced TMS-evoked SICI correlates with ADHD diagnosis and symptom severity and also reflects motor skill development in children. PMID:21321335

  4. Walking in School-Aged Children in a Dual-Task Paradigm Is Related to Age But Not to Cognition, Motor Behavior, Injuries, or Psychosocial Functioning

    PubMed Central

    Hagmann-von Arx, Priska; Manicolo, Olivia; Lemola, Sakari; Grob, Alexander

    2016-01-01

    Age-dependent gait characteristics and associations with cognition, motor behavior, injuries, and psychosocial functioning were investigated in 138 typically developing children aged 6.7–13.2 years (M = 10.0 years). Gait velocity, normalized velocity, and variability were measured using the walkway system GAITRite without an additional task (single task) and while performing a motor or cognitive task (dual task). Assessment of children’s cognition included tests for intelligence and executive functions; parents reported on their child’s motor behavior, injuries, and psychosocial functioning. Gait variability (an index of gait regularity) decreased with increasing age in both single- and dual-task walking. Dual-task gait decrements were stronger when children walked in the motor compared to the cognitive dual-task condition and decreased with increasing age in both dual-task conditions. Gait alterations from single- to dual-task conditions were not related to children’s cognition, motor behavior, injuries, or psychosocial functioning. PMID:27014158

  5. Global dysrhythmia of cerebro-basal ganglia-cerebellar networks underlies motor tics following striatal disinhibition.

    PubMed

    McCairn, Kevin W; Iriki, Atsushi; Isoda, Masaki

    2013-01-09

    Motor tics, a cardinal symptom of Tourette syndrome (TS), are hypothesized to arise from abnormalities within cerebro-basal ganglia circuits. Yet noninvasive neuroimaging of TS has previously identified robust activation in the cerebellum. To date, electrophysiological properties of cerebellar activation and its role in basal ganglia-mediated tic expression remain unknown. We performed multisite, multielectrode recordings of single-unit activity and local field potentials from the cerebellum, basal ganglia, and primary motor cortex using a pharmacologic monkey model of motor tics/TS. Following microinjections of bicuculline into the sensorimotor putamen, periodic tics occurred predominantly in the orofacial region, and a sizable number of cerebellar neurons showed phasic changes in activity associated with tic episodes. Specifically, 64% of the recorded cerebellar cortex neurons exhibited increases in activity, and 85% of the dentate nucleus neurons displayed excitatory, inhibitory, or multiphasic responses. Critically, abnormal discharges of cerebellar cortex neurons and excitatory-type dentate neurons mostly preceded behavioral tic onset, indicating their central origins. Latencies of pathological activity in the cerebellum and primary motor cortex substantially overlapped, suggesting that aberrant signals may be traveling along divergent pathways to these structures from the basal ganglia. Furthermore, the occurrence of tic movement was most closely associated with local field potential spikes in the cerebellum and primary motor cortex, implying that these structures may function as a gate to release overt tic movements. These findings indicate that tic-generating networks in basal ganglia mediated tic disorders extend beyond classical cerebro-basal ganglia circuits, leading to global network dysrhythmia including cerebellar circuits.

  6. OF TRYPANOSOMATIDS. ENDOTRANSFORMATIONS AND ABERRATIONS].

    PubMed

    Frolov, A O; Malysheva, M N; Kostygov, A Yu

    2016-01-01

    Endotransformations and aberrations of the life cycle in the evolutionary history of trypanosomatids (Kinetoplastea: Trypanosomatidae) are analyzed. We treat the term "endotransformations" as evolutionarily fixed changes of phases and/or developmental stages of parasites. By contrast, we treat aberrations as evolutionary unstable, periodically arising deformations of developmental phases of trypanosomatids, never leading to life cycle changes. Various examples of life cycle endotransformations and aberrations in representatives of the family Trypanosomatidae are discussed.

  7. Triphasic behavioral response of motor units to submaximal fatiguing exercise.

    PubMed

    Dorfman, L J; Howard, J E; McGill, K C

    1990-07-01

    We have measured the firing rate and amplitude of 4551 motor unit action potentials (MUAPs) recorded with concentric needle electrodes from the brachial biceps muscles of 10 healthy young adults before, during, and after 45 minutes of intermittent isometric exercise at 20% of maximum voluntary contraction (MVC), using an automatic method for decomposition of electromyographic activity (ADEMG). During and after exercise, MUAPs derived from contractions of 30% MVC showed progressive increase in mean firing rate (P less than or equal to .01) and amplitude (P less than or equal to .05). The firing rate increase preceded the rise in mean amplitude, and was evident prior to the development of fatigue, defined as reduction of MVC. Analysis of individual potentials revealed that the increase in firing rate and in amplitude reflected different MUAP subpopulations. A short-term (less than 1 minute) reduction in MUAP firing rates (P less than or equal to .05) was also observed at the onset of each test contraction. These findings suggest that motor units exhibit a triphasic behavioral response to prolonged submaximal exercise: (1) short-term decline and stabilization of onset firing rates, followed by (2) gradual and progressive increase in firing rates and firing variability, and then by (3) recruitment of additional (larger) motor units. The (2) and (3) components presumably compensate for loss of force-generating capacity in the exercising muscle, and give rise jointly to the well-known increase in total surface EMG which accompanies muscle fatigue.

  8. Altered synaptic phospholipid signaling in PRG-1 deficient mice induces exploratory behavior and motor hyperactivity resembling psychiatric disorders.

    PubMed

    Schneider, Patrick; Petzold, Sandra; Sommer, Angela; Nitsch, Robert; Schwegler, Herbert; Vogt, Johannes; Roskoden, Thomas

    2018-01-15

    Plasticity related gene 1 (PRG-1) is a neuron specific membrane protein located at the postsynaptic density of glutamatergic synapses. PRG-1 modulates signaling pathways of phosphorylated lipid substrates such as lysophosphatidic acid (LPA). Deletion of PRG-1 increases presynaptic glutamate release probability leading to neuronal over-excitation. However, due to its cortical expression, PRG-1 deficiency leading to increased glutamatergic transmission is supposed to also affect motor pathways. We therefore analyzed the effects of PRG-1 function on exploratory and motor behavior using homozygous PRG-1 knockout (PRG-1 -/- ) mice and PRG-1/LPA 2 -receptor double knockout (PRG-1 -/- /LPA 2 -/- ) mice in two open field settings of different size and assessing motor behavior in the Rota Rod test. PRG-1 -/- mice displayed significantly longer path lengths and higher running speed in both open field conditions. In addition, PRG-1 -/- mice spent significantly longer time in the larger open field and displayed rearing and self-grooming behavior. Furthermore PRG-1 -/- mice displayed stereotypical behavior resembling phenotypes of psychiatric disorders in the smaller sized open field arena. Altogether, this behavior is similar to the stereotypical behavior observed in animal models for psychiatric disease of autistic spectrum disorders which reflects a disrupted balance between glutamatergic and GABAergic synapses. These differences indicate an altered excitation/inhibition balance in neuronal circuits in PRG-1 -/- mice as recently shown in the somatosensory cortex [38]. In contrast, PRG-1 -/- /LPA 2 -/- did not show significant changes in behavior in the open field suggesting that these specific alterations were abolished when the LPA 2 -receptor was lacking. Our findings indicate that PRG-1 deficiency led to over-excitability caused by an altered LPA/LPA 2 -R signaling inducing a behavioral phenotype typically observed in animal models for psychiatric disorders. Copyright

  9. Adolescent Balloon Analog Risk Task and Behaviors that Influence Risk of Motor Vehicle Crash Injury

    PubMed Central

    Vaca, Federico E.; Walthall, Jessica M.; Ryan, Sheryl; Moriarty-Daley, Alison; Riera, Antonio; Crowley, Michael J.; Mayes, Linda C.

    2013-01-01

    Risk-taking propensity is a pivotal facet of motor vehicle crash involvement and subsequent traumatic injury in adolescents. Clinical encounters are important opportunities to identify teens with high risk-taking propensity who may later experience serious injury. Our objective was to compare self-reports of health risk behavior with performance on the Balloon Analog Risk Task (BART), a validated metric of risk-taking propensity, in adolescents during a clinical encounter. 100 adolescent patients from a hospital emergency department and adolescent health clinic completed a computer-based survey of self-reported risk behaviors including substance use behaviors and behaviors that influence crash involvement. They then completed the BART, a validated laboratory-based risk task in which participants earn points by pumping up a computer-generated balloon with greater pumps leading to increased chance of balloon explosion. 20 trials were undertaken. Mean number of pumps on the BART showed a correlation of .243 (p=.015) with self-reported driver/passenger behaviors and attitudes towards driving that influence risk of crash injury. Regression analyses showed that self-reports of substance use and mean number of pumps on the BART uniquely predict self-reports of behaviors influencing the risk of crash injury. The BART is a promising correlate of real-world risk-taking behavior related to traffic safety. It remains a valid predictor of behaviors influencing risk of crash injury when using just 10 trials, suggesting its utility as a quick and effective screening measure for use in busy clinical environments. This tool may be an important link to prevention interventions for those most at-risk for future motor vehicle crash involvement and injury. PMID:24406948

  10. Distinct alterations in motor & reward seeking behavior are dependent on the gestational age of exposure to LPS-induced maternal immune activation.

    PubMed

    Straley, Megan E; Van Oeffelen, Wesley; Theze, Sarah; Sullivan, Aideen M; O'Mahony, Siobhain M; Cryan, John F; O'Keeffe, Gerard W

    2017-07-01

    The dopaminergic system is involved in motivation, reward and the associated motor activities. Mesodiencephalic dopaminergic neurons in the ventral tegmental area (VTA) regulate motivation and reward, whereas those in the substantia nigra (SN) are essential for motor control. Defective VTA dopaminergic transmission has been implicated in schizophrenia, drug addiction and depression whereas dopaminergic neurons in the SN are lost in Parkinson's disease. Maternal immune activation (MIA) leading to in utero inflammation has been proposed to be a risk factor for these disorders, yet it is unclear how this stimulus can lead to the diverse disturbances in dopaminergic-driven behaviors that emerge at different stages of life in affected offspring. Here we report that gestational age is a critical determinant of the subsequent alterations in dopaminergic-driven behavior in rat offspring exposed to lipopolysaccharide (LPS)-induced MIA. Behavioral analysis revealed that MIA on gestational day 16 but not gestational day 12 resulted in biphasic impairments in motor behavior. Specifically, motor impairments were evident in early life, which were resolved by adolescence, but subsequently re-emerged in adulthood. In contrast, reward seeking behaviors were altered in offspring exposed MIA on gestational day 12. These changes were not due to a loss of dopaminergic neurons per se in the postnatal period, suggesting that they reflect functional changes in dopaminergic systems. This highlights that gestational age may be a key determinant of how MIA leads to distinct alterations in dopaminergic-driven behavior across the lifespan of affected offspring. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Effect of Implicit Perceptual-Motor Training on Decision-Making Skills and Underpinning Gaze Behavior in Combat Athletes.

    PubMed

    Milazzo, Nicolas; Farrow, Damian; Fournier, Jean F

    2016-08-01

    This study investigated the effect of a 12-session, implicit perceptual-motor training program on decision-making skills and visual search behavior of highly skilled junior female karate fighters (M age = 15.7 years, SD = 1.2). Eighteen participants were required to make (physical or verbal) reaction decisions to various attacks within different fighting scenarios. Fighters' performance and eye movements were assessed before and after the intervention, and during acquisition through the use of video-based and on-mat decision-making tests. The video-based test revealed that following training, only the implicit perceptual-motor group (n = 6) improved their decision-making accuracy significantly compared to a matched motor training (placebo, n = 6) group and a control group (n = 6). Further, the implicit training group significantly changed their visual search behavior by focusing on fewer locations for longer durations. In addition, the session-by-session analysis showed no significant improvement in decision accuracy between training session 1 and all the other sessions, except the last one. Coaches should devote more practice time to implicit learning approaches during perceptual-motor training program to achieve significant decision-making improvements and more efficient visual search strategy with elite athletes. © The Author(s) 2016.

  12. Monochromatic ocular wave aberrations in young monkeys

    PubMed Central

    Ramamirtham, Ramkumar; Kee, Chea-su; Hung, Li-Fang; Qiao-Grider, Ying; Roorda, Austin; Smith, Earl L.

    2006-01-01

    High-order monochromatic aberrations could potentially influence vision-dependent refractive development in a variety of ways. As a first step in understanding the effects of wave aberration on refractive development, we characterized the maturational changes that take place in the high-order aberrations of infant rhesus monkey eyes. Specifically, we compared the monochromatic wave aberrations of infant and adolescent animals and measured the longitudinal changes in the high-order aberrations of infant monkeys during the early period when emmetropization takes place. Our main findings were that (1) adolescent monkey eyes have excellent optical quality, exhibiting total RMS errors that were slightly better than those for adult human eyes that have the same numerical aperture and (2) shortly after birth, infant rhesus monkeys exhibited relatively larger magnitudes of high-order aberrations predominately spherical aberration, coma, and trefoil, which decreased rapidly to assume adolescent values by about 200 days of age. The results demonstrate that rhesus monkey eyes are a good model for studying the contribution of individual ocular components to the eye’s overall aberration structure, the mechanisms responsible for the improvements in optical quality that occur during early ocular development, and the effects of high-order aberrations on ocular growth and emmetropization. PMID:16750549

  13. Use of electric field sensors for recording respiration, heart rate, and stereotyped motor behaviors in the rodent home cage.

    PubMed

    Noble, Donald J; MacDowell, Camden J; McKinnon, Michael L; Neblett, Tamra I; Goolsby, William N; Hochman, Shawn

    2017-02-01

    Numerous environmental and genetic factors can contribute significantly to behavioral and cardiorespiratory variability observed experimentally. Affordable technologies that allow for noninvasive home cage capture of physio-behavioral variables should enhance understanding of inter-animal variability including after experimental interventions. We assessed whether EPIC electric field sensors (Plessey Semiconductors) embedded within or attached externally to a rodent's home cage could accurately record respiration, heart rate, and motor behaviors. Current systems for quantification of behavioral variables require expensive specialty equipment, while measures of respiratory and heart rate are often provided by surgically implanted or chronically affixed devices. Sensors accurately encoded imposed sinusoidal changes in electric field tested at frequencies ranging from 0.5-100Hz. Mini-metronome arm movements were easily detected, but response magnitude was highly distance dependent. Sensors accurately reported respiration during whole-body plethysmography. In anesthetized rodents, PVC tube-embedded sensors provided accurate mechanical detection of both respiratory and heart rate. Comparable success was seen in naturally behaving animals at rest or sleeping when sensors were attached externally. Video-verified motor behaviors (sniffing, grooming, chewing, and rearing) were detectable and largely separable by their characteristic voltage fluctuations. Larger movement-related events had comparably larger voltage dynamics that easily allowed for a broad approximation of overall motor activity. Spectrograms were used to quickly depict characteristic frequencies in long-lasting recordings, while filtering and thresholding software allowed for detection and quantification of movement-related physio-behavioral events. EPIC electric field sensors provide a means for affordable non-contact home cage detection of physio-behavioral variables. Copyright © 2016 Elsevier B.V. All

  14. Dominance of the Unaffected Hemisphere Motor Network and Its Role in the Behavior of Chronic Stroke Survivors

    PubMed Central

    Bajaj, Sahil; Housley, Stephen N.; Wu, David; Dhamala, Mukesh; James, G. A.; Butler, Andrew J.

    2016-01-01

    Balance of motor network activity between the two brain hemispheres after stroke is crucial for functional recovery. Several studies have extensively studied the role of the affected brain hemisphere to better understand changes in motor network activity following stroke. Very few studies have examined the role of the unaffected brain hemisphere and confirmed the test–retest reliability of connectivity measures on unaffected hemisphere. We recorded blood oxygenation level dependent functional magnetic resonance imaging (fMRI) signals from nine stroke survivors with hemiparesis of the left or right hand. Participants performed a motor execution task with affected hand, unaffected hand, and both hands simultaneously. Participants returned for a repeat fMRI scan 1 week later. Using dynamic causal modeling (DCM), we evaluated effective connectivity among three motor areas: the primary motor area (M1), the premotor cortex (PMC) and the supplementary motor area for the affected and unaffected hemispheres separately. Five participants’ manual motor ability was assessed by Fugl-Meyer Motor Assessment scores and root-mean square error of participants’ tracking ability during a robot-assisted game. We found (i) that the task performance with the affected hand resulted in strengthening of the connectivity pattern for unaffected hemisphere, (ii) an identical network of the unaffected hemisphere when participants performed the task with their unaffected hand, and (iii) the pattern of directional connectivity observed in the affected hemisphere was identical for tasks using the affected hand only or both hands. Furthermore, paired t-test comparison found no significant differences in connectivity strength for any path when compared with one-week follow-up. Brain-behavior linear correlation analysis showed that the connectivity patterns in the unaffected hemisphere more accurately reflected the behavioral conditions than the connectivity patterns in the affected hemisphere

  15. Iteration of ultrasound aberration correction methods

    NASA Astrophysics Data System (ADS)

    Maasoey, Svein-Erik; Angelsen, Bjoern; Varslot, Trond

    2004-05-01

    Aberration in ultrasound medical imaging is usually modeled by time-delay and amplitude variations concentrated on the transmitting/receiving array. This filter process is here denoted a TDA filter. The TDA filter is an approximation to the physical aberration process, which occurs over an extended part of the human body wall. Estimation of the TDA filter, and performing correction on transmit and receive, has proven difficult. It has yet to be shown that this method works adequately for severe aberration. Estimation of the TDA filter can be iterated by retransmitting a corrected signal and re-estimate until a convergence criterion is fulfilled (adaptive imaging). Two methods for estimating time-delay and amplitude variations in receive signals from random scatterers have been developed. One method correlates each element signal with a reference signal. The other method use eigenvalue decomposition of the receive cross-spectrum matrix, based upon a receive energy-maximizing criterion. Simulations of iterating aberration correction with a TDA filter have been investigated to study its convergence properties. A weak and strong human-body wall model generated aberration. Both emulated the human abdominal wall. Results after iteration improve aberration correction substantially, and both estimation methods converge, even for the case of strong aberration.

  16. Murine motor and behavior functional evaluations for acute 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxication.

    PubMed

    Hutter-Saunders, Jessica A L; Gendelman, Howard E; Mosley, R Lee

    2012-03-01

    Acute intoxication with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induces nigrostriatal neurodegeneration that reflects Parkinson's disease (PD) pathobiology. The model is commonly used for rodent studies of PD pathogenesis and diagnostics and for developmental therapeutics. However, tests of motor function in MPTP-intoxicated mice have yielded mixed results. This unmet need reflects, in part, lesion severity, animal variability, and the overall test sensitivity and specificity. In attempts to standardize rodent motor function and behavioral tests, mice were trained on the rotarod or habituated in an open field test chamber, and baseline performance measurements were collected prior to MPTP intoxication. One week following MPTP intoxication, motor function and behavior were assessed and baseline measurements applied to post-MPTP measurements with normalization to PBS controls. Rotarod and open field tests assessed in this manner demonstrated significant differences between MPTP- and saline-treated mice, while tests of neuromuscular strength and endurance did not. We conclude that the rotarod and open field tests provide reliable measures of motor function for MPTP-intoxicated mice.

  17. Perceptual and Motor Development in Infants and Children. Second Edition.

    ERIC Educational Resources Information Center

    Cratty, Bryant J.

    Motor behavior, motor performance, and motor learning are discussed at length within the context of infant and child development. Individual chapters focus on the following: the sensory-motor behavior of infants; analysis of selected perceptual-motor programs; beginnings of movement in infants; gross motor attributes in early childhood; visual…

  18. Regression rate behaviors of HTPB-based propellant combinations for hybrid rocket motor

    NASA Astrophysics Data System (ADS)

    Sun, Xingliang; Tian, Hui; Li, Yuelong; Yu, Nanjia; Cai, Guobiao

    2016-02-01

    The purpose of this paper is to characterize the regression rate behavior of hybrid rocket motor propellant combinations, using hydrogen peroxide (HP), gaseous oxygen (GOX), nitrous oxide (N2O) as the oxidizer and hydroxyl-terminated poly-butadiene (HTPB) as the based fuel. In order to complete this research by experiment and simulation, a hybrid rocket motor test system and a numerical simulation model are established. Series of hybrid rocket motor firing tests are conducted burning different propellant combinations, and several of those are used as references for numerical simulations. The numerical simulation model is developed by combining the Navies-Stokes equations with the turbulence model, one-step global reaction model, and solid-gas coupling model. The distribution of regression rate along the axis is determined by applying simulation mode to predict the combustion process and heat transfer inside the hybrid rocket motor. The time-space averaged regression rate has a good agreement between the numerical value and experimental data. The results indicate that the N2O/HTPB and GOX/HTPB propellant combinations have a higher regression rate, since the enhancement effect of latter is significant due to its higher flame temperature. Furthermore, the containing of aluminum (Al) and/or ammonium perchlorate(AP) in the grain does enhance the regression rate, mainly due to the more energy released inside the chamber and heat feedback to the grain surface by the aluminum combustion.

  19. Aberrant cerebellar connectivity in motor and association networks in schizophrenia

    PubMed Central

    Shinn, Ann K.; Baker, Justin T.; Lewandowski, Kathryn E.; Öngür, Dost; Cohen, Bruce M.

    2015-01-01

    Schizophrenia is a devastating illness characterized by disturbances in multiple domains. The cerebellum is involved in both motor and non-motor functions, and the “cognitive dysmetria” and “dysmetria of thought” models propose that abnormalities of the cerebellum may contribute to schizophrenia signs and symptoms. The cerebellum and cerebral cortex are reciprocally connected via a modular, closed-loop network architecture, but few schizophrenia neuroimaging studies have taken into account the topographical and functional heterogeneity of the cerebellum. In this study, using a previously defined 17-network cerebral cortical parcellation system as the basis for our functional connectivity seeds, we systematically investigated connectivity abnormalities within the cerebellum of 44 schizophrenia patients and 28 healthy control participants. We found selective alterations in cerebro-cerebellar functional connectivity. Specifically, schizophrenia patients showed decreased cerebro-cerebellar functional connectivity in higher level association networks (ventral attention, salience, control, and default mode networks) relative to healthy control participants. Schizophrenia patients also showed increased cerebro-cerebellar connectivity in somatomotor and default mode networks, with the latter showing no overlap with the regions found to be hypoconnected within the same default mode network. Finally, we found evidence to suggest that somatomotor and default mode networks may be inappropriately linked in schizophrenia. The relationship of these dysconnectivities to schizophrenia symptoms, such as neurological soft signs and altered sense of agency, is discussed. We conclude that the cerebellum ought to be considered for analysis in all future studies of network abnormalities in SZ, and further suggest the cerebellum as a potential target for further elucidation, and possibly treatment, of the underlying mechanisms and network abnormalities producing symptoms of

  20. Neural correlates of the age-related changes in motor sequence learning and motor adaptation in older adults

    PubMed Central

    King, Bradley R.; Fogel, Stuart M.; Albouy, Geneviève; Doyon, Julien

    2013-01-01

    As the world's population ages, a deeper understanding of the relationship between aging and motor learning will become increasingly relevant in basic research and applied settings. In this context, this review aims to address the effects of age on motor sequence learning (MSL) and motor adaptation (MA) with respect to behavioral, neurological, and neuroimaging findings. Previous behavioral research investigating the influence of aging on motor learning has consistently reported the following results. First, the initial acquisition of motor sequences is not altered, except under conditions of increased task complexity. Second, older adults demonstrate deficits in motor sequence memory consolidation. And, third, although older adults demonstrate deficits during the exposure phase of MA paradigms, the aftereffects following removal of the sensorimotor perturbation are similar to young adults, suggesting that the adaptive ability of older adults is relatively intact. This paper will review the potential neural underpinnings of these behavioral results, with a particular emphasis on the influence of age-related dysfunctions in the cortico-striatal system on motor learning. PMID:23616757

  1. [Monochromatic aberration in accommodation. Dynamic wavefront analysis].

    PubMed

    Fritzsch, M; Dawczynski, J; Jurkutat, S; Vollandt, R; Strobel, J

    2011-06-01

    Monochromatic aberrations may influence the visual acuity of the eye. They are not stable and can be affected by different factors. The subject of the following paper is the dynamic investigation of the changes in wavefront aberration with accommodation. Dynamic measurement of higher and lower order aberrations was performed with a WASCA Wavefront Analyzer (Carl-Zeiss-Meditec) and a specially constructed target device for aligning objects in far and near distances on 25 subjects aged from 15 to 27 years old. Wavefront aberrations showed some significant changes in accommodation. In addition to the characteristic sphere reaction accompanying miosis and changes in horizontal prism (Z(1) (1)) in the sense of a convergence movement of the eyeball also occurred. Furthermore defocus rose (Z(2) (0)) and astigmatism (Z(2) (-2)) changed. In higher-order aberrations a decrease in coma-like Zernike polynomials (Z(3) (-1), Z(3) (1)) was found. The most obvious change appeared in spherical aberration (Z(4) (0)) which increased and changed from positive to negative. In addition the secondary astigmatism (Z(4) (-2)) and quadrafoil (Z(4) (4)) rise also increased. The total root mean square (RMS), as well as the higher-order aberrations (RMS-HO) significantly increased in accommodation which is associated with a theoretical reduction of visual acuity. An analysis of the influence of pupil size on aberrations showed significant increases in defocus, spherical aberration, quadrafoil, RMS and RMS HO by increasing pupil diameter. By accommodation-associated miosis, the growing aberrations are partially compensated by focusing on near objects. Temporal analysis of the accommodation process with dynamic wavefront analysis revealed significant delays in pupil response and changing of prism in relation to the sphere reaction. In accommodation to near objects a discrete time ahead of third order aberrations in relation to the sphere response was found. Using dynamic wavefront measurement

  2. Wavefront aberrations of x-ray dynamical diffraction beams.

    PubMed

    Liao, Keliang; Hong, Youli; Sheng, Weifan

    2014-10-01

    The effects of dynamical diffraction in x-ray diffractive optics with large numerical aperture render the wavefront aberrations difficult to describe using the aberration polynomials, yet knowledge of them plays an important role in a vast variety of scientific problems ranging from optical testing to adaptive optics. Although the diffraction theory of optical aberrations was established decades ago, its application in the area of x-ray dynamical diffraction theory (DDT) is still lacking. Here, we conduct a theoretical study on the aberration properties of x-ray dynamical diffraction beams. By treating the modulus of the complex envelope as the amplitude weight function in the orthogonalization procedure, we generalize the nonrecursive matrix method for the determination of orthonormal aberration polynomials, wherein Zernike DDT and Legendre DDT polynomials are proposed. As an example, we investigate the aberration evolution inside a tilted multilayer Laue lens. The corresponding Legendre DDT polynomials are obtained numerically, which represent balanced aberrations yielding minimum variance of the classical aberrations of an anamorphic optical system. The balancing of classical aberrations and their standard deviations are discussed. We also present the Strehl ratio of the primary and secondary balanced aberrations.

  3. Characterizing Sexual Behavior in Frontotemporal Dementia.

    PubMed

    Ahmed, Rebekah M; Kaizik, Cassandra; Irish, Muireann; Mioshi, Eneida; Dermody, Nadene; Kiernan, Matthew C; Piguet, Olivier; Hodges, John R

    2015-01-01

    Frontotemporal dementia (FTD) is characterized by a number of prominent behavioral changes. While FTD has been associated with the presence of aberrant or unusual sexual behaviors in a proportion of patients, few studies have formally investigated changes in sexual function in this disease. We aimed to systematically quantify changes in sexual behavior, including current symptoms and changes from prior diagnoses, in behavioral-variant (bvFTD) and semantic dementia (SD), compared to Alzheimer's disease (AD). Carers of 49 dementia patients (21 bvFTD, 11 SD, 17 AD) were interviewed using the Sexual Behavior and Intimacy Questionnaire (SIQ), a survey designed to assess changes in sexual function across multiple domains including initiating, level of affection, and aberrant or unusual sexual behavior. BvFTD patients show prominent hyposexual behavior including decreased affection, initiation, and response to advances by partners, and decreased frequency of sexual relations, compared to AD and to SD patients. The greatest changes in sexual behavior compared to pre-diagnoses were found in the bvFTD group with a 90-100% decrease in initiation, response, and frequency of sexual relations. Notably, aberrant or unusual sexual behavior was reported in a minority of bvFTD and SD patients and occurred in patients who also showed hyposexual behavior toward their partner. Overall loss of affection, reduced initiation of sexual activity, and responsiveness is an overwhelming feature of bvFTD. In contrast, aberrant or unusual sexual behavior is observed in the minority of bvFTD patients. The underlying pathophysiology of these changes likely reflects structural and functional changes in frontoinsular and limbic regions including the hypothalamus.

  4. Automated Detection of Repetitive Motor Behaviors as an Outcome Measurement in Intellectual and Developmental Disabilities

    ERIC Educational Resources Information Center

    Gilchrist, Kristin H.; Hegarty-Craver, Meghan; Christian, Robert B.; Grego, Sonia; Kies, Ashley C.; Wheeler, Anne C.

    2018-01-01

    Repetitive sensory motor behaviors are a direct target for clinical treatment and a potential treatment endpoint for individuals with intellectual or developmental disabilities. By removing the burden associated with video annotation or direct observation, automated detection of stereotypy would allow for longer term monitoring in ecologic…

  5. On the Definition of Aberration

    NASA Astrophysics Data System (ADS)

    Xu, Minghui; Wang, Guangli

    2014-12-01

    There was a groundbreaking step in the history of astronomy in 1728 when the effect of aberration was discovered by James Bradley (1693-1762). Recently, the solar acceleration, due to the variations in the aberrational effect of extragalactic sources caused by it, has been determined from VLBI observations with an uncertainty of about 0.5 mm{\\cdot}{s^{-1}}{\\cdot}{yr^{-1}} level. As a basic concept in astrometry with a nearly 300-year history, the definition of aberration, however, is still equivocal and discordant in the literature. It has been under continuing debate whether it depends on the relative motion between the observer and the observed source or only on the motion of the observer with respect to the frame of reference. In this paper, we will review the debate and the inconsistency in the definition of the aberration since the last century, and then discuss its definition in detail, which involves the discussions on the planetary aberration, the stellar aberration, the proper motion of an object during the travel time of light from the object to the observer, and the way of selecting the reference frame to express and distinguish the motions of the source and the observer. The aberration is essentially caused by the transformation between coordinate systems, and consequently quantified by the velocity of the observer with respect to the selected reference frame, independent of the motion of the source. Obviously, this nature is totally different from that of the definition given by the IAU WG NFA (Capitaine, 2007) in 2006, which is stated as, ``the apparent angular displacement of the observed position of a celestial object from its geometric position, caused by the finite velocity of light in combination with the motions of the observer and of the observed object.''

  6. Treadmill exercise delays the onset of non-motor behaviors and striatal pathology in the CAG140 knock-in mouse model of Huntington's disease.

    PubMed

    Stefanko, D P; Shah, V D; Yamasaki, W K; Petzinger, G M; Jakowec, M W

    2017-09-01

    Depression, cognitive impairments, and other neuropsychiatric disturbances are common during the prodromal phase of Huntington's disease (HD) well before the onset of classical motor symptoms of this degenerative disorder. The purpose of this study was to examine the potential impact of physical activity in the form of exercise on a motorized treadmill on non-motor behavioral features including depression-like behavior and cognition in the CAG 140 knock-in (KI) mouse model of HD. The CAG 140 KI mouse model has a long lifespan compared to other HD rodent models with HD motor deficits emerging after 12months of age and thus provides the opportunity to investigate early life interventions such as exercise on disease progression. Motorized treadmill running was initiated at 4weeks of age (1h per session, 3 times per week) and continued for 6months. Non-motor behaviors were assessed up to 6months of age and included analysis of depression-like behavior (using the tail-suspension and forced-swim tests) and cognition (using the T-maze and object recognition tests). At both 4 and 6months of age, CAG 140 KI mice displayed significant depression-like behavior in the forced swim and tail suspension tests and cognitive impairment by deficits in reversal relearning in the T-maze test. These deficits were not evident in mice engaged in treadmill running. In addition, exercise restored striatal dopamine D2 receptor expression and dopamine neurotransmitter levels both reduced in sedentary HD mice. Finally, we examined the pattern of striatal expression of mutant huntingtin (mHTT) protein and showed that the number and intensity of immunohistochemical staining patterns of intranuclear aggregates were significantly reduced with exercise. Altogether these findings begin to address the potential impact of lifestyle and early intervention such as exercise on modifying HD progression. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. A New Type of Motor: Pneumatic Step Motor

    PubMed Central

    Stoianovici, Dan; Patriciu, Alexandru; Petrisor, Doru; Mazilu, Dumitru; Kavoussi, Louis

    2011-01-01

    This paper presents a new type of pneumatic motor, a pneumatic step motor (PneuStep). Directional rotary motion of discrete displacement is achieved by sequentially pressurizing the three ports of the motor. Pulsed pressure waves are generated by a remote pneumatic distributor. The motor assembly includes a motor, gearhead, and incremental position encoder in a compact, central bore construction. A special electronic driver is used to control the new motor with electric stepper indexers and standard motion control cards. The motor accepts open-loop step operation as well as closed-loop control with position feedback from the enclosed sensor. A special control feature is implemented to adapt classic control algorithms to the new motor, and is experimentally validated. The speed performance of the motor degrades with the length of the pneumatic hoses between the distributor and motor. Experimental results are presented to reveal this behavior and set the expectation level. Nevertheless, the stepper achieves easily controllable precise motion unlike other pneumatic motors. The motor was designed to be compatible with magnetic resonance medical imaging equipment, for actuating an image-guided intervention robot, for medical applications. For this reason, the motors were entirely made of nonmagnetic and dielectric materials such as plastics, ceramics, and rubbers. Encoding was performed with fiber optics, so that the motors are electricity free, exclusively using pressure and light. PneuStep is readily applicable to other pneumatic or hydraulic precision-motion applications. PMID:21528106

  8. Effect of monochromatic aberrations on photorefractive patterns

    NASA Astrophysics Data System (ADS)

    Campbell, Melanie C. W.; Bobier, W. R.; Roorda, A.

    1995-08-01

    Photorefractive methods have become popular in the measurement of refractive and accommodative states of infants and children owing to their photographic nature and rapid speed of measurement. As in the case of any method that measures the refractive state of the human eye, monochromatic aberrations will reduce the accuracy of the measurement. Monochromatic aberrations cannot be as easily predicted or controlled as chromatic aberrations during the measurement, and accordingly they will introduce measurement errors. This study defines this error or uncertainty by extending the existing paraxial optical analyses of coaxial and eccentric photorefraction. This new optical analysis predicts that, for the amounts of spherical aberration (SA) reported for the human eye, there will be a significant degree of measurement uncertainty introduced for all photorefractive methods. The dioptric amount of this uncertainty may exceed the maximum amount of SA present in the eye. The calculated effects on photorefractive measurement of a real eye with a mixture of spherical aberration and coma are shown to be significant. The ability, developed here, to predict photorefractive patterns corresponding to different amounts and types of monochromatic aberration may in the future lead to an extension of photorefractive methods to the dual measurement of refractive states and aberrations of individual eyes. aberration, retinal image quality,

  9. Reducing the Stress of Intensive Care: Effects on Motor and State Behavior. Conference Summary.

    ERIC Educational Resources Information Center

    Becker, Patricia T.

    This report presents outcome data on infant motor activity and behavioral state. Subjects were 45 infants who had birth weight of less than 1,501 grams, were appropriate for gestational age, and were free of major complications. A total of 21 infants were studied during a preintervention (control period), and 24 were studied in a posttraining…

  10. Motor stereotypy disorders.

    PubMed

    Muthugovindan, Deivasumathy; Singer, Harvey

    2009-04-01

    This review highlights recent advances in understanding the clinical features, prevalence, and outcomes of motor stereotypy disorders in typically developing children. Longitudinal data indicate that stereotypies in children with normal intelligence show an early age of onset, chronicity, and high prevalence of comorbid difficulties, including tics, obsessive-compulsive behaviors, and attention deficit hyperactivity disorder. The underlying abnormality remains unknown, but there is increasing evidence for Mendelian inheritance and a neurobiological mechanism. Primary motor stereotypies are relatively common in childhood and can be subdivided into three groups (common, head nodding, and complex motor). Movements are similar to those seen in children with autistic spectrum disorders, mental retardation, and sensory deprivation. The role of pharmacotherapy is not established and behavioral therapy can be beneficial.

  11. Behavioral Problems in Children with Motor and Intellectual Disabilities: Prevalence and Associations with Maladaptive Personality and Marital Relationship

    ERIC Educational Resources Information Center

    Vrijmoeth, Cis; Monbaliu, Elegast; Lagast, Emmy; Prinzie, Peter

    2012-01-01

    Prevalence rates of behavioral problems in children with motor disabilities are commonly based on questionnaires developed for a general population (e.g., Child Behavior CheckList). These questionnaires do not take into account lower levels of intellectual functioning. The first aim of this study was to examine the prevalence of parent-reported…

  12. IGF-1 delivery to CNS attenuates motor neuron cell death but does not improve motor function in type III SMA mice.

    PubMed

    Tsai, Li-Kai; Chen, Yi-Chun; Cheng, Wei-Cheng; Ting, Chen-Hung; Dodge, James C; Hwu, Wuh-Liang; Cheng, Seng H; Passini, Marco A

    2012-01-01

    The efficacy of administering a recombinant adeno-associated virus (AAV) vector encoding human IGF-1 (AAV2/1-hIGF-1) into the deep cerebellar nucleus (DCN) of a type III SMA mouse model was evaluated. High levels of IGF-1 transcripts and protein were detected in the spinal cord at 2 months post-injection demonstrating that axonal connections between the cerebellum and spinal cord were able to act as conduits for the viral vector and protein to the spinal cord. Mice treated with AAV2/1-hIGF-1 and analyzed 8 months later showed changes in endogenous Bax and Bcl-xl levels in spinal cord motor neurons that were consistent with IGF-1-mediated anti-apoptotic effects on motor neurons. However, although AAV2/1-hIGF-1 treatment reduced the extent of motor neuron cell death, the majority of rescued motor neurons were non-functional, as they lacked axons that innervated the muscles. Furthermore, treated SMA mice exhibited abnormal muscle fibers, aberrant neuromuscular junction structure, and impaired performance on motor function tests. These data indicate that although CNS-directed expression of IGF-1 could reduce motor neuron cell death, this did not translate to improvements in motor function in an adult mouse model of type III SMA. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Pomegranate Supplementation Improves Affective and Motor Behavior in Mice after Radiation Exposure

    PubMed Central

    Dulcich, Melissa S.; Hartman, Richard E.

    2013-01-01

    Currently, NASA has plans for extended space travel, and previous research indicates that space radiation can have negative effects on cognitive skills as well as physical and mental health. With long-term space travel, astronauts will be exposed to greater radiation levels. Research shows that an antioxidant-enriched diet may offer some protection against the cellular effects of radiation and may provide significant neuroprotection from the effects of radiation-induced cognitive and behavioral skill deficits. Ninety-six C57BL/6 mice (48 pomegranate fed and 48 control) were irradiated with proton radiation (2 Gy), and two-month postradiation behaviors were assessed using a battery of behavioral tests to measure cognitive and motor functions. Proton irradiation was associated with depression-like behaviors in the tail suspension test, but this effect was ameliorated by the pomegranate diet. Males, in general, displayed worse coordination and balance than females on the rotarod task, and the pomegranate diet ameliorated this effect. Overall, it appears that proton irradiation, which may be encountered in space, may induce a different pattern of behavioral deficits in males than females and that a pomegranate diet may confer protection against some of those effects. PMID:23662154

  14. Variations in Static Force Control and Motor Unit Behavior with Error Amplification Feedback in the Elderly.

    PubMed

    Chen, Yi-Ching; Lin, Linda L; Lin, Yen-Ting; Hu, Chia-Ling; Hwang, Ing-Shiou

    2017-01-01

    Error amplification (EA) feedback is a promising approach to advance visuomotor skill. As error detection and visuomotor processing at short time scales decline with age, this study examined whether older adults could benefit from EA feedback that included higher-frequency information to guide a force-tracking task. Fourteen young and 14 older adults performed low-level static isometric force-tracking with visual guidance of typical visual feedback and EA feedback containing augmented high-frequency errors. Stabilogram diffusion analysis was used to characterize force fluctuation dynamics. Also, the discharge behaviors of motor units and pooled motor unit coherence were assessed following the decomposition of multi-channel surface electromyography (EMG). EA produced different behavioral and neurophysiological impacts on young and older adults. Older adults exhibited inferior task accuracy with EA feedback than with typical visual feedback, but not young adults. Although stabilogram diffusion analysis revealed that EA led to a significant decrease in critical time points for both groups, EA potentiated the critical point of force fluctuations [Formula: see text], short-term effective diffusion coefficients (Ds), and short-term exponent scaling only for the older adults. Moreover, in older adults, EA added to the size of discharge variability of motor units and discharge regularity of cumulative discharge rate, but suppressed the pooled motor unit coherence in the 13-35 Hz band. Virtual EA alters the strategic balance between open-loop and closed-loop controls for force-tracking. Contrary to expectations, the prevailing use of closed-loop control with EA that contained high-frequency error information enhanced the motor unit discharge variability and undermined the force steadiness in the older group, concerning declines in physiological complexity in the neurobehavioral system and the common drive to the motoneuronal pool against force destabilization.

  15. Variations in Static Force Control and Motor Unit Behavior with Error Amplification Feedback in the Elderly

    PubMed Central

    Chen, Yi-Ching; Lin, Linda L.; Lin, Yen-Ting; Hu, Chia-Ling; Hwang, Ing-Shiou

    2017-01-01

    Error amplification (EA) feedback is a promising approach to advance visuomotor skill. As error detection and visuomotor processing at short time scales decline with age, this study examined whether older adults could benefit from EA feedback that included higher-frequency information to guide a force-tracking task. Fourteen young and 14 older adults performed low-level static isometric force-tracking with visual guidance of typical visual feedback and EA feedback containing augmented high-frequency errors. Stabilogram diffusion analysis was used to characterize force fluctuation dynamics. Also, the discharge behaviors of motor units and pooled motor unit coherence were assessed following the decomposition of multi-channel surface electromyography (EMG). EA produced different behavioral and neurophysiological impacts on young and older adults. Older adults exhibited inferior task accuracy with EA feedback than with typical visual feedback, but not young adults. Although stabilogram diffusion analysis revealed that EA led to a significant decrease in critical time points for both groups, EA potentiated the critical point of force fluctuations <ΔFc2>, short-term effective diffusion coefficients (Ds), and short-term exponent scaling only for the older adults. Moreover, in older adults, EA added to the size of discharge variability of motor units and discharge regularity of cumulative discharge rate, but suppressed the pooled motor unit coherence in the 13–35 Hz band. Virtual EA alters the strategic balance between open-loop and closed-loop controls for force-tracking. Contrary to expectations, the prevailing use of closed-loop control with EA that contained high-frequency error information enhanced the motor unit discharge variability and undermined the force steadiness in the older group, concerning declines in physiological complexity in the neurobehavioral system and the common drive to the motoneuronal pool against force destabilization. PMID:29167637

  16. Imaging characteristics of Zernike and annular polynomial aberrations.

    PubMed

    Mahajan, Virendra N; Díaz, José Antonio

    2013-04-01

    The general equations for the point-spread function (PSF) and optical transfer function (OTF) are given for any pupil shape, and they are applied to optical imaging systems with circular and annular pupils. The symmetry properties of the PSF, the real and imaginary parts of the OTF, and the modulation transfer function (MTF) of a system with a circular pupil aberrated by a Zernike circle polynomial aberration are derived. The interferograms and PSFs are illustrated for some typical polynomial aberrations with a sigma value of one wave, and 3D PSFs and MTFs are shown for 0.1 wave. The Strehl ratio is also calculated for polynomial aberrations with a sigma value of 0.1 wave, and shown to be well estimated from the sigma value. The numerical results are compared with the corresponding results in the literature. Because of the same angular dependence of the corresponding annular and circle polynomial aberrations, the symmetry properties of systems with annular pupils aberrated by an annular polynomial aberration are the same as those for a circular pupil aberrated by a corresponding circle polynomial aberration. They are also illustrated with numerical examples.

  17. Corneal spherical aberration in Saudi population

    PubMed Central

    Al-Sayyari, Tarfah M.; Fawzy, Samah M.; Al-Saleh, Ahmed A.

    2014-01-01

    Purpose To find out the mean corneal spherical aberration and its changes with age in Saudi population. Setting AlHokama Eye Specialist Center, Riyadh, Saudi Arabia. Methods Three hundred (300) eyes of 185 Saudi subjects (97 men and 88 women), whose age ranged from 15 to 85 years old, with matched refractive errors, were divided into three groups according to their age, 100 for each. All the subjects were included in measuring the spherical aberration (SA) using pentacam HR (OCULUS, Germany) at the 6-mm optical zone. Results The mean corneal spherical aberration (CSA) of the fourth order (Z40) of the whole groups was 0.252 ± 0.1154 μm. Patients from 15 to 35 years old have root mean square (RMS) of CSA of 0.2068 ± 0.07151 μm, 0.2370 ± 0.08023 μm was the RMS of CSA of the patients from 35 to 50 years old, while those from 50 to 85 years old have a CSA-RMS of 0.31511 ± 0.1503 μm (P < 0.0001). A positive correlation was found between the spherical aberration (Z40) and the progress of age (r = 0.3429, P < 0.0001). The high order aberration (HOA) presented 28.1% of the total corneal aberrations. While the fourth order corneal spherical aberration constituted 57% of the HOA and 16% of the total aberration. The pupil diameter shows a negative correlation with the increase in age (P = 0.0012). Conclusion Our results showed a CSA (Z40) that is varied among the population, comparable to other studies, and significantly correlates to the progress of age. PMID:25278799

  18. Manganese-Enhanced Magnetic Resonance Imaging and Studies of Rat Behavior: Transient Motor Deficit in Skilled Reaching, Rears, and Activity in Rats After a Single Dose of MnCl2.

    PubMed

    Alaverdashvili, Mariam; Lapointe, Valerie; Whishaw, Ian Q; Cross, Albert R

    2017-01-01

    Manganese-enhanced magnetic resonance imaging (MEMRI) has been suggested to be a useful tool to visualize and map behavior-relevant neural populations at large scale in freely behaving rodents. A primary concern in MEMRI applications is Mn 2+ toxicity. Although a few studies have specifically examined toxicity on gross motor behavior, Mn 2+ toxicity on skilled motor behavior was not explored. Thus, the objective of this study was to combine manganese as a functional contrast agent with comprehensive behavior evaluation. We evaluated Mn 2+ effect on skilled reach-to-eat action, locomotion, and balance using a single pellet reaching task, activity cage, and cylinder test, respectively. The tests used are sensitive to the pathophysiology of many neurological and neurodegenerative disorders of the motor system. The behavioral testing was done in combination with a moderate dose of manganese. Behavior was studied before and after a single, intravenous infusion of MnCl 2 (48 mg/kg). The rats were imaged at 1, 3, 5, 7, and 14 days following infusion. The results show that MnCl 2 infusion resulted in detectable abnormalities in skilled reaching, locomotion, and balance that recovered within 3 days compared with the infusion of saline. Because some tests and behavioral measures could not detect motor abnormalities of skilled movements, comprehensive evaluation of motor behavior is critical in assessing the effects of MnCl 2 . The relaxation mapping results suggest that the transport of Mn 2+ into the brain is through the choroid plexus-cerebrospinal fluid system with the primary entry point and highest relaxation rates found in the pituitary gland. Relaxation rates in the pituitary gland correlated with measures of motor skill, suggesting that altered motor ability is related to the level of Mn circulating in the brain. Thus, combined MEMRI and behavioral studies that both achieve adequate image enhancement and are also free of motor skills deficits are difficult to achieve

  19. Isoflurane anesthesia has long-term consequences on motor and behavioral development in infant rhesus macaques

    PubMed Central

    Coleman, Kristine; Robertson, Nicola D.; Dissen, Gregory A.; Neuringer, Martha D.; Martin, L. Drew; Cuzon Carlson, Verginia C.; Kroenke, Christopher; Fair, Damien; Brambrink, Ansgar

    2016-01-01

    Background Experimental evidence correlates anesthetic exposure during early development with neuronal and glial injury and death as well as behavioral and cognitive impairments in young animals. Several, although not all, retrospective human studies of neurocognitive and behavioral disorders following childhood exposure to anesthesia suggest a similar association. Few studies have specifically investigated the effects of infant anesthesia exposure on subsequent neurobehavioral development. Using a highly translational nonhuman primate model, we investigated the potential dose-dependent effects of anesthesia across the first year of development. Methods We examined effects of single or multiple early postnatal isoflurane exposures on subsequent behavioral development in 24 socially reared rhesus macaques. Infants were exposed to 5-h of isoflurane anesthesia either once, three times, or not at all (control). We assessed reflex development and anxiety using standardized tests. At approximately one year, infants (n=23) were weaned and housed indoors with 5-6 other subjects. We recorded their response to this move and re-assessed anxiety. Results Compared to controls, animals exposed to repeated isoflurane (ISO-3) presented with motor reflex deficits at 1 month (median, range: ISO-3= 2 [1–5] versus control= 5 [3–7], p<0.005) and responded to their new social environment with increased anxiety (median, range: ISO-3=0.4 bouts/minute [0.2–0.6]; control= 0.25 [0.1–0.3], p,0.05) and affiliative/appeasement behavior (median, range: ISO-3=0.1 bouts/min [0–0.2]; control= 0 [0–0.1], p<0.01) at 12 months. There were no statistically significant behavioral alterations after single isoflurane exposure. Conclusions Neonatal exposure to isoflurane, particularly when repeated, has long-term behavioral consequences affecting both motor and socio-emotional aspects of behavior. PMID:27749311

  20. Transcranial phase aberration correction using beam simulations and MR-ARFI

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vyas, Urvi, E-mail: urvi.vyas@gmail.com; Kaye, Elena; Pauly, Kim Butts

    2014-03-15

    Purpose: Transcranial magnetic resonance-guided focused ultrasound surgery is a noninvasive technique for causing selective tissue necrosis. Variations in density, thickness, and shape of the skull cause aberrations in the location and shape of the focal zone. In this paper, the authors propose a hybrid simulation-MR-ARFI technique to achieve aberration correction for transcranial MR-guided focused ultrasound surgery. The technique uses ultrasound beam propagation simulations with MR Acoustic Radiation Force Imaging (MR-ARFI) to correct skull-caused phase aberrations. Methods: Skull-based numerical aberrations were obtained from a MR-guided focused ultrasound patient treatment and were added to all elements of the InSightec conformal bone focusedmore » ultrasound surgery transducer during transmission. In the first experiment, the 1024 aberrations derived from a human skull were condensed into 16 aberrations by averaging over the transducer area of 64 elements. In the second experiment, all 1024 aberrations were applied to the transducer. The aberrated MR-ARFI images were used in the hybrid simulation-MR-ARFI technique to find 16 estimated aberrations. These estimated aberrations were subtracted from the original aberrations to result in the corrected images. Each aberration experiment (16-aberration and 1024-aberration) was repeated three times. Results: The corrected MR-ARFI image was compared to the aberrated image and the ideal image (image with zero aberrations) for each experiment. The hybrid simulation-MR-ARFI technique resulted in an average increase in focal MR-ARFI phase of 44% for the 16-aberration case and 52% for the 1024-aberration case, and recovered 83% and 39% of the ideal MR-ARFI phase for the 16-aberrations and 1024-aberration case, respectively. Conclusions: Using one MR-ARFI image and noa priori information about the applied phase aberrations, the hybrid simulation-MR-ARFI technique improved the maximum MR-ARFI phase of the beam's focus.« less

  1. The effects of yoga practice in school physical education on children's motor abilities and social behavior.

    PubMed

    Folleto, Júlia C; Pereira, Keila Rg; Valentini, Nadia Cristina

    2016-01-01

    In recent years, yoga programs in childhood have been implemented in schools, to promote the development for children. To investigate the effects of yoga program in physical education classes on the motor abilities and social behavior parameters of 6-8-year-old children. The study included 16 children from the 1(st) grade of a public elementary school in the South of Brazil. The children participated in a 12-week intervention, twice weekly, with 45 min each session. To assess children's performance, we used the Bruininks-Oseretsky Test of Motor Proficiency - Second Edition, the flexibility test (sit and reach - Eurofit, 1988), the Pictorial Scale of Perceived Competence and Social Acceptance for Young Children and semi-structured interviews with children, parents, and classroom' teacher. Data were analyzed with Wilcoxon test and level of significance was 5%. The yoga program was well accepted by children, children also demonstrated significant and positive changes in overall motor abilities scores (balance, strength, and flexibility). In addition, the interviews reported changing in social behavior and the use of the knowledge learned in the program in contexts outside of school. These findings suggest that the implementation of yoga practice in physical education lessons contributed to children's development.

  2. The effects of yoga practice in school physical education on children's motor abilities and social behavior

    PubMed Central

    Folleto, Júlia C; Pereira, Keila RG; Valentini, Nadia Cristina

    2016-01-01

    Background: In recent years, yoga programs in childhood have been implemented in schools, to promote the development for children. Aim: To investigate the effects of yoga program in physical education classes on the motor abilities and social behavior parameters of 6–8-year-old children. Methods: The study included 16 children from the 1st grade of a public elementary school in the South of Brazil. The children participated in a 12-week intervention, twice weekly, with 45 min each session. To assess children's performance, we used the Bruininks-Oseretsky Test of Motor Proficiency - Second Edition, the flexibility test (sit and reach – Eurofit, 1988), the Pictorial Scale of Perceived Competence and Social Acceptance for Young Children and semi-structured interviews with children, parents, and classroom’ teacher. Data were analyzed with Wilcoxon test and level of significance was 5%. Results: The yoga program was well accepted by children, children also demonstrated significant and positive changes in overall motor abilities scores (balance, strength, and flexibility). In addition, the interviews reported changing in social behavior and the use of the knowledge learned in the program in contexts outside of school. Conclusion: These findings suggest that the implementation of yoga practice in physical education lessons contributed to children's development. PMID:27512323

  3. Anti-forensics of chromatic aberration

    NASA Astrophysics Data System (ADS)

    Mayer, Owen; Stamm, Matthew C.

    2015-03-01

    Over the past decade, a number of information forensic techniques have been developed to identify digital image manipulation and falsification. Recent research has shown, however, that an intelligent forger can use anti-forensic countermeasures to disguise their forgeries. In this paper, an anti-forensic technique is proposed to falsify the lateral chromatic aberration present in a digital image. Lateral chromatic aberration corresponds to the relative contraction or expansion between an image's color channels that occurs due to a lens's inability to focus all wavelengths of light on the same point. Previous work has used localized inconsistencies in an image's chromatic aberration to expose cut-and-paste image forgeries. The anti-forensic technique presented in this paper operates by estimating the expected lateral chromatic aberration at an image location, then removing deviations from this estimate caused by tampering or falsification. Experimental results are presented that demonstrate that our anti-forensic technique can be used to effectively disguise evidence of an image forgery.

  4. A Evaluation of Optical Aberrations in Underwater Hologrammetry

    NASA Astrophysics Data System (ADS)

    Kilpatrick, J. M.

    Available from UMI in association with The British Library. An iterative ray-trace procedure is developed in conjunction with semi-analytic expressions for spherical aberration, coma, and astigmatism in the reconstructed holographic images of underwater objects. An exact expression for the astigmatic difference is obtained, based on the geometry of the caustic for refraction. The geometrical characteristics of the aberrated images associated with axial and non-axial field positions are represented by ray intersection diagrams. A third order expression for the wavefront aberration introduced at a planar air/water boundary is given. The associated third order aberration coefficients are used to obtain analytic expressions for the aberrations observed in underwater hologrammetry. The results of the third order treatment are shown to give good agreement with the results obtained by geometrical ray tracing and by direct measurement on the reconstructed real image. The third order aberration coefficients are employed to estimate the limit of resolution in the presence of the aberrations associated with reconstruction in air. In concurrence with practical observations it is found that the estimated resolution is primarily limited by astigmatism. The limitations of the planar window in underwater imaging applications are outlined and various schemes are considered to effect a reduction in the extent of aberration. The analogous problems encountered in underwater photography are examined in order to establish the grounds for a common solution based on a conventional optical corrector. The performance of one such system, the Ivanoff Corrector, is investigated. The spherical aberration associated with axial image formation is evaluated. The equivalence of the third order wavefront aberration introduced at a planar air/water boundary to that introduced upon reconstruction by an appropriate wavelength change is shown to provide a basis for the compensation of aberrations in

  5. Driving Human Motor Cortical Oscillations Leads to Behaviorally Relevant Changes in Local GABAA Inhibition: A tACS-TMS Study

    PubMed Central

    van Ede, Freek

    2017-01-01

    Beta and gamma oscillations are the dominant oscillatory activity in the human motor cortex (M1). However, their physiological basis and precise functional significance remain poorly understood. Here, we used transcranial magnetic stimulation (TMS) to examine the physiological basis and behavioral relevance of driving beta and gamma oscillatory activity in the human M1 using transcranial alternating current stimulation (tACS). tACS was applied using a sham-controlled crossover design at individualized intensity for 20 min and TMS was performed at rest (before, during, and after tACS) and during movement preparation (before and after tACS). We demonstrated that driving gamma frequency oscillations using tACS led to a significant, duration-dependent decrease in local resting-state GABAA inhibition, as quantified by short interval intracortical inhibition. The magnitude of this effect was positively correlated with the magnitude of GABAA decrease during movement preparation, when gamma activity in motor circuitry is known to increase. In addition, gamma tACS-induced change in GABAA inhibition was closely related to performance in a motor learning task such that subjects who demonstrated a greater increase in GABAA inhibition also showed faster short-term learning. The findings presented here contribute to our understanding of the neurophysiological basis of motor rhythms and suggest that tACS may have similar physiological effects to endogenously driven local oscillatory activity. Moreover, the ability to modulate local interneuronal circuits by tACS in a behaviorally relevant manner provides a basis for tACS as a putative therapeutic intervention. SIGNIFICANCE STATEMENT Gamma oscillations have a vital role in motor control. Using a combined tACS-TMS approach, we demonstrate that driving gamma frequency oscillations modulates GABAA inhibition in the human motor cortex. Moreover, there is a clear relationship between the change in magnitude of GABAA inhibition induced

  6. Driving Human Motor Cortical Oscillations Leads to Behaviorally Relevant Changes in Local GABAA Inhibition: A tACS-TMS Study.

    PubMed

    Nowak, Magdalena; Hinson, Emily; van Ede, Freek; Pogosyan, Alek; Guerra, Andrea; Quinn, Andrew; Brown, Peter; Stagg, Charlotte J

    2017-04-26

    Beta and gamma oscillations are the dominant oscillatory activity in the human motor cortex (M1). However, their physiological basis and precise functional significance remain poorly understood. Here, we used transcranial magnetic stimulation (TMS) to examine the physiological basis and behavioral relevance of driving beta and gamma oscillatory activity in the human M1 using transcranial alternating current stimulation (tACS). tACS was applied using a sham-controlled crossover design at individualized intensity for 20 min and TMS was performed at rest (before, during, and after tACS) and during movement preparation (before and after tACS). We demonstrated that driving gamma frequency oscillations using tACS led to a significant, duration-dependent decrease in local resting-state GABA A inhibition, as quantified by short interval intracortical inhibition. The magnitude of this effect was positively correlated with the magnitude of GABA A decrease during movement preparation, when gamma activity in motor circuitry is known to increase. In addition, gamma tACS-induced change in GABA A inhibition was closely related to performance in a motor learning task such that subjects who demonstrated a greater increase in GABA A inhibition also showed faster short-term learning. The findings presented here contribute to our understanding of the neurophysiological basis of motor rhythms and suggest that tACS may have similar physiological effects to endogenously driven local oscillatory activity. Moreover, the ability to modulate local interneuronal circuits by tACS in a behaviorally relevant manner provides a basis for tACS as a putative therapeutic intervention. SIGNIFICANCE STATEMENT Gamma oscillations have a vital role in motor control. Using a combined tACS-TMS approach, we demonstrate that driving gamma frequency oscillations modulates GABA A inhibition in the human motor cortex. Moreover, there is a clear relationship between the change in magnitude of GABA A inhibition

  7. Attenuation of the Type IV Pilus Retraction Motor Influences Neisseria gonorrhoeae Social and Infection Behavior.

    PubMed

    Hockenberry, Alyson M; Hutchens, Danielle M; Agellon, Al; So, Magdalene

    2016-12-06

    Retraction of the type IV pilus (Tfp) mediates DNA uptake, motility, and social and infection behavior in a wide variety of prokaryotes. To date, investigations into Tfp retraction-dependent activities have used a mutant deleted of PilT, the ATPase motor protein that causes the pilus fiber to retract. ΔpilT cells are nontransformable, nonmotile, and cannot aggregate into microcolonies. We tested the hypothesis that these retraction-dependent activities are sensitive to the strength of PilT enzymatic activity by using the pathogen Neisseria gonorrhoeae as a model. We constructed an N. gonorrhoeae mutant with an amino acid substitution in the PilT Walker B box (a substitution of cysteine for leucine at position 201, encoded by pilT L201C ). Purified PilT L201C forms a native hexamer, but mutant hexamers hydrolyze ATP at half the maximal rate. N. gonorrhoeae pilT L201C cells produce Tfp fibers, crawl at the same speed as the wild-type (wt) parent, and are equally transformable. However, the social behavior of pilT L201C cells is intermediate between the behaviors of wt and ΔpilT cells. The infection behavior of pilT L201C is also defective, due to its failure to activate the epidermal growth factor receptor (EGFR)-heparin-binding EGF-like growth factor (HB-EGF) pathway. Our study indicates that pilus retraction, per se, is not sufficient for N. gonorrhoeae microcolony formation or infectivity; rather, these activities are sensitive to the strength of PilT enzymatic activity. We discuss the implications of these findings for Neisseria pathogenesis in the context of mechanobiology. Type IV pili are fibers expressed on the surface of many bacteria. Neisseria gonorrhoeae cells crawl, take up DNA, and communicate with each other and with human cells by retracting these fibers. Here, we show that an N. gonorrhoeae mutant expressing an enzymatically weakened type IV pilus retraction motor still crawls and takes up DNA normally. However, mutant cells exhibit abnormal

  8. Administration of Lactobacillus helveticus NS8 improves behavioral, cognitive, and biochemical aberrations caused by chronic restraint stress.

    PubMed

    Liang, S; Wang, T; Hu, X; Luo, J; Li, W; Wu, X; Duan, Y; Jin, F

    2015-12-03

    Increasing numbers of studies have suggested that the gut microbiota is involved in the pathophysiology of stress-related disorders. Chronic stress can cause behavioral, cognitive, biochemical, and gut microbiota aberrations. Gut bacteria can communicate with the host through the microbiota-gut-brain axis (which mainly includes the immune, neuroendocrine, and neural pathways) to influence brain and behavior. It is hypothesized that administration of probiotics can improve chronic-stress-induced depression. In order to examine this hypothesis, the chronic restraint stress depression model was established in this study. Adult specific pathogen free (SPF) Sprague-Dawley rats were subjected to 21 days of restraint stress followed by behavioral testing (including the sucrose preference test (SPT), elevated-plus maze test, open-field test (OFT), object recognition test (ORT), and object placement test (OPT)) and biochemical analysis. Supplemental Lactobacillus helveticus NS8 was provided every day during stress until the end of experiment, and selective serotonin reuptake inhibitor (SSRI) citalopram (CIT) served as a positive control. Results showed that L. helveticus NS8 improved chronic restraint stress-induced behavioral (anxiety and depression) and cognitive dysfunction, showing an effect similar to and better than that of CIT. L. helveticus NS8 also resulted in lower plasma corticosterone (CORT) and adrenocorticotropic hormone (ACTH) levels, higher plasma interleukin-10 (IL-10) levels, restored hippocampal serotonin (5-HT) and norepinephrine (NE) levels, and more hippocampal brain-derived neurotrophic factor (BDNF) mRNA expression than in chronic stress rats. Taken together, these results indicate an anti-depressant effect of L. helveticus NS8 in rats subjected to chronic restraint stress depression and that this effect could be due to the microbiota-gut-brain axis. They also suggest the therapeutic potential of L. helveticus NS8 in stress-related and possibly other

  9. Unknown Pseudocholinesterase Deficiency in a Patient Undergoing TIVA with Planned Motor Evoked Potential Monitoring: A Case Report.

    PubMed

    Binkley, Candace

    2016-06-01

    Pseudocholinesterase abnormalities are a genetic cause of aberrant metabolism of the depolarizing muscle relaxant succinylcholine. This article examines a case where succinylcholine was chosen to facilitate intubation due to its ultra short duration and the request of the surgeon to monitor motor evoked potentials. Following succinylcholine administration the neurophysiologist was unable to obtain motor evoked potentials. This case study highlights the intraoperative and postoperative management of an elderly patient with an unknown pseudocholinesterase deficiency.

  10. Design of space-borne imager with wide field of view based on freeform aberration theory

    NASA Astrophysics Data System (ADS)

    Shi, Haodong; Zhang, Jizhen; Wang, Lingjie; Zhang, Xin; Jiang, Huilin

    2016-10-01

    Freeform surfaces have advantages on balancing asymmetric aberration of the unobscured push-broom imager. However, since the conventional paraxial aberration theory is no longer appropriate for the freeform system design, designers are lack of insights on the imaging quality from the freeform aberration distribution. In order to design the freeform optical system efficiently, the contribution and nodal behavior of coma and astigmatism introduced by Standard Zernike polynomial surface are discussed in detail. An unobscured three-mirror optical system with 850 mm effective focal length, 20°× 2° field of view (FOV) is designed. The coma and astigmatism nodal positions are moved into the real-FOV by selecting and optimizing the Zernike terms pointedly, which has balanced the off-axis asymmetric aberration. The results show that the modulation transfer function (MTF) is close to diffraction limit, and the distortion throughout full-FOV is less than 0.25%. At last, a computer-generated hologram (CGH) for freeform surface testing is designed. The CGH design error RMS is lower than λ/1000 at 632.8 nm, which meets the requirements for measurement.

  11. Lower- and higher-order aberrations predicted by an optomechanical model of arcuate keratotomy for astigmatism.

    PubMed

    Navarro, Rafael; Palos, Fernando; Lanchares, Elena; Calvo, Begoña; Cristóbal, José A

    2009-01-01

    To develop a realistic model of the optomechanical behavior of the cornea after curved relaxing incisions to simulate the induced astigmatic change and predict the optical aberrations produced by the incisions. ICMA Consejo Superior de Investigaciones Científicas and Universidad de Zaragoza, Zaragoza, Spain. A 3-dimensional finite element model of the anterior hemisphere of the ocular surface was used. The corneal tissue was modeled as a quasi-incompressible, anisotropic hyperelastic constitutive behavior strongly dependent on the physiological collagen fibril distribution. Similar behaviors were assigned to the limbus and sclera. With this model, some corneal incisions were computer simulated after the Lindstrom nomogram. The resulting geometry of the biomechanical simulation was analyzed in the optical zone, and finite ray tracing was performed to compute refractive power and higher-order aberrations (HOAs). The finite-element simulation provided new geometry of the corneal surfaces, from which elevation topographies were obtained. The surgically induced astigmatism (SIA) of the simulated incisions according to the Lindstrom nomogram was computed by finite ray tracing. However, paraxial computations would yield slightly different results (undercorrection of astigmatism). In addition, arcuate incisions would induce significant amounts of HOAs. Finite-element models, together with finite ray-tracing computations, yielded realistic simulations of the biomechanical and optical changes induced by relaxing incisions. The model reproduced the SIA indicated by the Lindstrom nomogram for the simulated incisions and predicted a significant increase in optical aberrations induced by arcuate keratotomy.

  12. Monoaminergic Modulation of Motor Cortex Function

    PubMed Central

    Vitrac, Clément; Benoit-Marand, Marianne

    2017-01-01

    Elaboration of appropriate responses to behavioral situations rests on the ability of selecting appropriate motor outcomes in accordance to specific environmental inputs. To this end, the primary motor cortex (M1) is a key structure for the control of voluntary movements and motor skills learning. Subcortical loops regulate the activity of the motor cortex and thus contribute to the selection of appropriate motor plans. Monoamines are key mediators of arousal, attention and motivation. Their firing pattern enables a direct encoding of different states thus promoting or repressing the selection of actions adapted to the behavioral context. Monoaminergic modulation of motor systems has been extensively studied in subcortical circuits. Despite evidence of converging projections of multiple neurotransmitters systems in the motor cortex pointing to a direct modulation of local circuits, their contribution to the execution and learning of motor skills is still poorly understood. Monoaminergic dysregulation leads to impaired plasticity and motor function in several neurological and psychiatric conditions, thus it is critical to better understand how monoamines modulate neural activity in the motor cortex. This review aims to provide an update of our current understanding on the monoaminergic modulation of the motor cortex with an emphasis on motor skill learning and execution under physiological conditions. PMID:29062274

  13. Peripheral and central changes combine to induce motor behavioral deficits in a moderate repetition task.

    PubMed

    Coq, Jacques-Olivier; Barr, Ann E; Strata, Fabrizio; Russier, Michael; Kietrys, David M; Merzenich, Michael M; Byl, Nancy N; Barbe, Mary F

    2009-12-01

    Repetitive motion disorders, such as carpal tunnel syndrome and focal hand dystonia, can be associated with tasks that require prolonged, repetitive behaviors. Previous studies using animal models of repetitive motion have correlated cortical neuroplastic changes or peripheral tissue inflammation with fine motor performance. However, the possibility that both peripheral and central mechanisms coexist with altered motor performance has not been studied. In this study, we investigated the relationship between motor behavior changes associated with repetitive behaviors and both peripheral tissue inflammation and cortical neuroplasticity. A rat model of reaching and grasping involving moderate repetitive reaching with negligible force (MRNF) was used. Rats performed the MRNF task for 2 h/day, 3 days/week for 8 weeks. Reach performance was monitored by measuring reach rate/success, daily exposure, reach movement reversals/patterns, reach/grasp phase times, grip strength and grooming function. With cumulative task exposure, reach performance, grip strength and agility declined while an inefficient food retrieval pattern increased. In S1 of MRNF rats, a dramatic disorganization of the topographic forepaw representation was observed, including the emergence of large receptive fields located on both the wrist/forearm and forepaw with alterations of neuronal properties. In M1, there was a drastic enlargement of the overall forepaw map area, and of the cortex devoted to digit, arm-digits and elbow-wrist responses. In addition, unusually low current amplitude evoked digit movements. IL-1 beta and TNF-alpha increased in forearm flexor muscles and tendons of MRNF animals. The increases in IL-1 beta and TNF-alpha negatively correlated with grip strength and amount of current needed to evoke forelimb movements. This study provides strong evidence that both peripheral inflammation and cortical neuroplasticity jointly contribute to the development of chronic repetitive motion

  14. Aberrated laser beams in terms of Zernike polynomials

    NASA Astrophysics Data System (ADS)

    Alda, Javier; Alonso, Jose; Bernabeu, Eusebio

    1996-11-01

    The characterization of light beams has devoted a lot of attention in the past decade. Several formalisms have been presented to treat the problem of parameter invariance and characterization in the propagation of light beam along ideal, ABCD, optical systems. The hard and soft apertured optical systems have been treated too. Also some aberrations have been analyzed, but it has not appeared a formalism able to treat the problem as a whole. In this contribution we use a classical approach to describe the problem of aberrated, and therefore apertured, light beams. The wavefront aberration is included in a pure phase term expanded in terms of the Zernike polynomials. Then, we can use the relation between the lower order Zernike polynomia and the Seidel or third order aberrations. We analyze the astigmatism, the spherical aberration and the coma, and we show how higher order aberrations can be taken into account. We have calculated the divergence, and the radius of curvature of such aberrated beams and the influence of these aberrations in the quality of the light beam. Some numerical simulations have been done to illustrate the method.

  15. Delta-9-tetrahydrocannabinol (THC) affects forelimb motor map expression but has little effect on skilled and unskilled behavior.

    PubMed

    Scullion, K; Guy, A R; Singleton, A; Spanswick, S C; Hill, M N; Teskey, G C

    2016-04-05

    It has previously been shown in rats that acute administration of delta-9-tetrahydrocannabinol (THC) exerts a dose-dependent effect on simple locomotor activity, with low doses of THC causing hyper-locomotion and high doses causing hypo-locomotion. However the effect of acute THC administration on cortical movement representations (motor maps) and skilled learned movements is completely unknown. It is important to determine the effects of THC on motor maps and skilled learned behaviors because behaviors like driving place people at a heightened risk. Three doses of THC were used in the current study: 0.2mg/kg, 1.0mg/kg and 2.5mg/kg representing the approximate range of the low to high levels of available THC one would consume from recreational use of cannabis. Acute peripheral administration of THC to drug naïve rats resulted in dose-dependent alterations in motor map expression using high resolution short duration intracortical microstimulation (SD-ICMS). THC at 0.2mg/kg decreased movement thresholds and increased motor map size, while 1.0mg/kg had the opposite effect, and 2.5mg/kg had an even more dramatic effect. Deriving complex movement maps using long duration (LD)-ICMS at 1.0mg/kg resulted in fewer complex movements. Dosages of 1.0mg/kg and 2.5mg/kg THC reduced the number of reach attempts but did not affect percentage of success or the kinetics of reaching on the single pellet skilled reaching task. Rats that received 2.5mg/kg THC did show an increase in latency of forelimb removal on the bar task, while dose-dependent effects of THC on unskilled locomotor activity using the rotorod and horizontal ladder tasks were not observed. Rats may be employing compensatory strategies after receiving THC, which may account for the robust changes in motor map expression but moderate effects on behavior. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  16. Whole eye wavefront aberrations in Mexican male subjects.

    PubMed

    Cantú, Roberto; Rosales, Marco A; Tepichín, Eduardo; Curioca, Andrée; Montes, Victor; Bonilla, Julio

    2004-01-01

    To analyze the characteristics, incidence, and appearance of wavefront aberrations in undilated, normal, unoperated eyes. Eighty-eight eyes of 44 healthy male Mexican subjects (mean age 25.32 years, range 18 to 36 yr) were divided into three groups based on uncorrected visual acuity of greater than or equal to 20/20, 20/30, or 20/40. UCVA measurements were obtained using an Acuity Max computer screen chart. Wavefront aberrations were measured with the Nidek OPD-Scan ARK 10000, Ver. 1.11b. All measurements were carried out at the same center by the same technician during a single session, following manufacturer instructions. Background illumination was 3 Lux. Wavefront aberration measurements for each group were statistically analyzed using StatView; an average eye was characterized and the resulting aberrations were simulated using MATLAB. We obtained wavefront aberration maps for the 20/20 undilated normal unoperated eyes for total, low, and high order aberration coefficients. Wavefront maps for right eyes were practically the same as those for left eyes. Higher aberrations did not contribute substantially to total wavefront analysis. Average aberrations of this "normal eye" will be used as criteria to decide the necessity of wavefront-guided ablation in our facilities. We will focus on the nearly zero average of high order aberrations in this normal whole eye as a reference to be matched.

  17. Effects of moderate prenatal ethanol exposure and age on social behavior, spatial response perseveration errors and motor behavior

    PubMed Central

    Hamilton, Derek A.; Barto, Daniel; Rodriguez, Carlos I.; Magcalas, Christy; Fink, Brandi C.; Rice, James P.; Bird, Clark W.; Davies, Suzy; Savage, Daniel D.

    2014-01-01

    Persistent deficits in social behavior are among the major negative consequences associated with exposure to ethanol during prenatal development. Prior work from our laboratory has linked deficits in social behavior following moderate prenatal alcohol exposure (PAE) in the rat to functional alterations in the ventrolateral frontal cortex [21]. In addition to social behaviors, the regions comprising the ventrolateral frontal cortex are critical for diverse processes ranging from orofacial motor movements to flexible alteration of behavior in the face of changing consequences. The broader behavioral implications of altered ventrolateral frontal cortex function following moderate PAE have, however, not been examined. In the present study we evaluated the consequences of moderate PAE on social behavior, tongue protrusion, and flexibility in a variant of the Morris water task that required modification of a well-established spatial response. PAE rats displayed deficits in tongue protrusion, reduced flexibility in the spatial domain, increased wrestling, and decreased investigation, indicating that several behaviors associated with ventrolateral frontal cortex function are impaired following moderate PAE. A linear discriminant analysis revealed that measures of wrestling and tongue protrusion provided the best discrimination of PAE rats from saccharin-exposed control rats. We also evaluated all behaviors in young adult (4-5 mos.) or older (10-11 mos.) rats to address the persistence of behavioral deficits in adulthood and possible interactions between early ethanol exposure and advancing age. Behavioral deficits in each domain persisted well into adulthood (10-11 mos.), however, there was no evidence that age enhances the effects of moderate PAE within the age ranges that were studied. PMID:24769174

  18. Accommodation to wavefront vergence and chromatic aberration.

    PubMed

    Wang, Yinan; Kruger, Philip B; Li, James S; Lin, Peter L; Stark, Lawrence R

    2011-05-01

    Longitudinal chromatic aberration (LCA) provides a cue to accommodation with small pupils. However, large pupils increase monochromatic aberrations, which may obscure chromatic blur. In this study, we examined the effect of pupil size and LCA on accommodation. Accommodation was recorded by infrared optometer while observers (nine normal trichromats) viewed a sinusoidally moving Maltese cross target in a Badal stimulus system. There were two illumination conditions: white (3000 K; 20 cd/m) and monochromatic (550 nm with 10 nm bandwidth; 20 cd/m) and two artificial pupil conditions (3 and 5.7 mm). Separately, static measurements of wavefront aberration were made with the eye accommodating to targets between 0 and 4 D (COAS, Wavefront Sciences). Large individual differences in accommodation to wavefront vergence and to LCA are a hallmark of accommodation. LCA continues to provide a signal at large pupil sizes despite higher levels of monochromatic aberrations. Monochromatic aberrations may defend against chromatic blur at high spatial frequencies, but accommodation responds best to optical vergence and to LCA at 3 c/deg where blur from higher order aberrations is less.

  19. Dynamic Re-wiring of Neural Circuits in the Motor Cortex in Mouse Models of Parkinson's Disease

    PubMed Central

    Lalchandani, Rupa R.; Cui, Yuting; Shu, Yu; Xu, Tonghui; Ding, Jun B.

    2015-01-01

    SUMMARY Dynamic adaptations in synaptic plasticity are critical for learning new motor skills and maintaining memory throughout life, which rapidly decline with Parkinson's disease (PD). Plasticity in the motor cortex is important for acquisition and maintenance of novel motor skills, but how the loss of dopamine in PD leads to disrupted structural and functional plasticity in the motor cortex is not well understood. Here, we utilized mouse models of PD and 2-photon imaging to show that dopamine depletion resulted in structural changes in the motor cortex. We further discovered that dopamine D1 and D2 receptor signaling were linked to selectively and distinctly regulating these aberrant changes in structural and functional plasticity. Our findings suggest that both D1 and D2 receptor signaling regulate motor cortex plasticity, and loss of dopamine results in atypical synaptic adaptations that may contribute to the impairment of motor performance and motor memory observed in PD. PMID:26237365

  20. Motor Cortex Reorganization across the Lifespan

    ERIC Educational Resources Information Center

    Plowman, Emily K.; Kleim, Jeffrey A.

    2010-01-01

    The brain is a highly dynamic structure with the capacity for profound structural and functional change. Such neural plasticity has been well characterized within motor cortex and is believed to represent one of the neural mechanisms for acquiring and modifying motor behaviors. A number of behavioral and neural signals have been identified that…

  1. Motor planning modulates sensory-motor control of collision avoidance behavior in the bullfrog, Rana catesbeiana

    PubMed Central

    Nakagawa, Hideki; Nishida, Yuuya

    2012-01-01

    Summary In this study, we examined the collision avoidance behavior of the frog, Rana catesbeiana to an approaching object in the upper visual field. The angular velocity of the frog's escape turn showed a significant positive correlation with the turn angle (r2 = 0.5741, P<0.05). A similar mechanism of velocity control has been known in head movements of the owl and in human saccades. By analogy, this suggests that the frog planned its escape velocity in advance of executing the turn, to make the duration of the escape behavior relatively constant. For escape turns less than 60°, the positive correlation was very strong (r2 = 0.7097, P<0.05). Thus, the frog controlled the angular velocity of small escape turns very accurately and completed the behavior within a constant time. On the other hand, for escape turns greater than 60°, the same correlation was not significant (r2 = 0.065, P>0.05). Thus, the frog was not able to control the velocity of the large escape turns accurately and did not complete the behavior within a constant time. In the latter case, there was a small but significant positive correlation between the threshold angular size and the angular velocity (r2 = 0.1459, P<0.05). This suggests that the threshold is controlled to compensate for the insufficient escape velocity achieved during large turn angles, and could explain a significant negative correlation between the turn angle and the threshold angular size (r2 = 0.1145, P<0.05). Thus, it is likely that the threshold angular size is also controlled by the turn angle and is modulated by motor planning. PMID:23213389

  2. Social Motor Synchronization: Insights for Understanding Social Behavior in Autism.

    PubMed

    Fitzpatrick, Paula; Romero, Veronica; Amaral, Joseph L; Duncan, Amie; Barnard, Holly; Richardson, Michael J; Schmidt, R C

    2017-07-01

    Impairments in social interaction and communication are critical features of ASD but the underlying processes are poorly understood. An under-explored area is the social motor synchronization that happens when we coordinate our bodies with others. Here, we explored the relationships between dynamical measures of social motor synchronization and assessments of ASD traits. We found (a) spontaneous social motor synchronization was associated with responding to joint attention, cooperation, and theory of mind while intentional social motor synchronization was associated with initiating joint attention and theory of mind; and (b) social motor synchronization was associated with ASD severity but not fully explained by motor problems. Findings suggest that objective measures of social motor synchronization may provide insights into understanding ASD traits.

  3. Regional specificity of aberrant thalamocortical connectivity in autism.

    PubMed

    Nair, Aarti; Carper, Ruth A; Abbott, Angela E; Chen, Colleen P; Solders, Seraphina; Nakutin, Sarah; Datko, Michael C; Fishman, Inna; Müller, Ralph-Axel

    2015-11-01

    Preliminary evidence suggests aberrant (mostly reduced) thalamocortical (TC) connectivity in autism spectrum disorder (ASD), but despite the crucial role of thalamus in sensorimotor functions and its extensive connectivity with cerebral cortex, relevant evidence remains limited. We performed a comprehensive investigation of region-specific TC connectivity in ASD. Resting-state functional MRI and diffusion tensor imaging (DTI) data were acquired for 60 children and adolescents with ASD (ages 7-17 years) and 45 age, sex, and IQ-matched typically developing (TD) participants. We examined intrinsic functional connectivity (iFC) and anatomical connectivity (probabilistic tractography) with thalamus, using 68 unilateral cerebral cortical regions of interest (ROIs). For frontal and parietal lobes, iFC was atypically reduced in the ASD group for supramodal association cortices, but was increased for cingulate gyri and motor cortex. Temporal iFC was characterized by overconnectivity for auditory cortices, but underconnectivity for amygdalae. Occipital iFC was broadly reduced in the ASD group. DTI indices (such as increased radial diffusion) for regions with group differences in iFC further indicated compromised anatomical connectivity, especially for frontal ROIs, in the ASD group. Our findings highlight the regional specificity of aberrant TC connectivity in ASD. Their overall pattern can be largely accounted for by functional overconnectivity with limbic and sensorimotor regions, but underconnectivity with supramodal association cortices. This could be related to comparatively early maturation of limbic and sensorimotor regions in the context of early overgrowth in ASD, at the expense of TC connectivity with later maturing cortical regions. © 2015 Wiley Periodicals, Inc.

  4. Aberrant temporal behavior of mismatch negativity generators in schizophrenia patients and subjects at clinical high risk for psychosis.

    PubMed

    Kim, Minah; Cho, Kang Ik Kevin; Yoon, Youngwoo Bryan; Lee, Tae Young; Kwon, Jun Soo

    2017-02-01

    Although disconnection syndrome has been considered a core pathophysiologic mechanism of schizophrenia, little is known about the temporal behavior of mismatch negativity (MMN) generators in individuals with schizophrenia or clinical high risk (CHR) for psychosis. MMN was assessed in 29 schizophrenia patients, 40 CHR subjects, and 47 healthy controls (HCs). Individual realistic head models and the minimum L2 norm algorithm were used to generate a current source density (CSD) model of MMN. The strength and time course of MMN CSD activity were calculated separately for the frontal and temporal cortices and were compared across brain regions and groups. Schizophrenia patients and CHR subjects displayed lower MMN CSD strength than HCs in both the temporal and frontal cortices. We found a significant time delay in MMN generator activity in the frontal cortex relative to that in the temporal cortex in HCs. However, the sequential temporo-frontal activities of MMN generators were disrupted in both the schizophrenia and CHR groups. Impairments and altered temporal behavior of MMN multiple generators were observed even in individuals at risk for psychosis. These findings suggest that aberrant MMN generator activity might be helpful in revealing the pathophysiology of schizophrenia. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  5. The effects of gestational and chronic atrazine exposure on motor behaviors and striatal dopamine in male Sprague-Dawley rats

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Walters, Jennifer L., E-mail: Jennifer.l.walters@wmich.edu; Lansdell, Theresa A., E-mail: lansdel1@msu.edu; Lookingland, Keith J., E-mail: lookingl@msu.edu

    This study sought to investigate the effects of environmentally relevant gestational followed by continued chronic exposure to the herbicide, atrazine, on motor function, cognition, and neurochemical indices of nigrostriatal dopamine (DA) activity in male rats. Dams were treated with 100 μg/kg atrazine, 10 mg/kg atrazine, or vehicle on gestational day 1 through postnatal day 21. Upon weaning, male offspring continued daily vehicle or atrazine gavage treatments for an additional six months. Subjects were tested in a series of behavioral assays, and 24 h after the last treatment, tissue samples from the striatum were analyzed for DA and 3,4-dihydroxyphenylacetic acid (DOPAC).more » At 10 mg/kg, this herbicide was found to produce modest disruptions in motor functioning, and at both dose levels it significantly lowered striatal DA and DOPAC concentrations. These results suggest that exposures to atrazine have the potential to disrupt nigrostriatal DA neurons and behaviors associated with motor functioning. - Highlights: • Male rats received gestational and chronic exposure to ATZ (10 mg/kg and 100 μg/kg). • ATZ altered locomotor activity and impaired motor coordination. • ATZ lowered striatal DA and DOPAC concentrations. • ATZ produced a potential anxiogenic effect. • ATZ did not impair performance in learning and memory assessments.« less

  6. Relations of Preschoolers' Visual-Motor and Object Manipulation Skills with Executive Function and Social Behavior

    ERIC Educational Resources Information Center

    MacDonald, Megan; Lipscomb, Shannon; McClelland, Megan M.; Duncan, Rob; Becker, Derek; Anderson, Kim; Kile, Molly

    2016-01-01

    Purpose: The purpose of this article was to examine specific linkages between early visual-motor integration skills and executive function, as well as between early object manipulation skills and social behaviors in the classroom during the preschool year. Method: Ninety-two children aged 3 to 5 years old (M[subscript age] = 4.31 years) were…

  7. Sixth-order wave aberration theory of ultrawide-angle optical systems.

    PubMed

    Lu, Lijun; Cao, Yiqing

    2017-10-20

    In this paper, we develop sixth-order wave aberration theory of ultrawide-angle optical systems like fisheye lenses. Based on the concept and approach to develop wave aberration theory of plane-symmetric optical systems, we first derive the sixth-order intrinsic wave aberrations and the fifth-order ray aberrations; second, we present a method to calculate the pupil aberration of such kind of optical systems to develop the extrinsic aberrations; third, the relation of aperture-ray coordinates between adjacent optical surfaces is fitted with the second-order polynomial to improve the calculation accuracy of the wave aberrations of a fisheye lens with a large acceptance aperture. Finally, the resultant aberration expressions are applied to calculate the aberrations of two design examples of fisheye lenses; the calculation results are compared with the ray-tracing ones with Zemax software to validate the aberration expressions.

  8. The Sensorimotor System Can Sculpt Behaviorally Relevant Representations for Motor Learning

    PubMed Central

    2016-01-01

    Abstract The coordinate system in which humans learn novel motor skills is controversial. The representation of sensorimotor skills has been extensively studied by examining generalization after learning perturbations specifically designed to be ambiguous as to their coordinate system. Recent studies have found that learning is not represented in any simple coordinate system and can potentially be accounted for by a mixed representation. Here, instead of probing generalization, which has led to conflicting results, we examine whether novel dynamics can be learned when explicitly and unambiguously presented in particular coordinate systems. Subjects performed center–out reaches to targets in the presence of a force field, while varying the orientation of their hand (i.e., the wrist angle) across trials. Different groups of subjects experienced force fields that were explicitly presented either in Cartesian coordinates (field independent of hand orientation), in object coordinates (field rotated with hand orientation), or in anti-object coordinates (field rotated counter to hand orientation). Subjects learned to represent the dynamics when presented in either Cartesian or object coordinates, learning these as well as an ambiguous force field. However, learning was slower for the object-based dynamics and substantially impaired for the anti-object presentation. Our results show that the motor system is able to tune its representation to at least two natural coordinate systems but is impaired when the representation of the task does not correspond to a behaviorally relevant coordinate system. Our results show that the motor system can sculpt its representation through experience to match those of natural tasks. PMID:27588304

  9. Independent mediation of unconditioned motor behavior by striatal D1 and D2 receptors in rats depleted of dopamine as neonates.

    PubMed

    Bruno, J P; Byrnes, E M; Johnson, B J

    1995-11-01

    The effects of systemic administration of DA receptor antagonists suggest that unconditioned motor behavior in rats depleted of DA as neonates continues to be dependent upon dopaminergic transmission, yet the specific contribution of D1 and D2 receptors to these behaviors has been altered. The purpose of the present study was to determine whether these depletion-induced receptor changes are occurring at the level of striatal DA terminals and their targets. The ability of bilateral intrastriatal injections (0.5 microliter) of DA receptor antagonists to induce motoric deficits was determined in adult rats treated with vehicle or 6-OHDA (100 micrograms, intraventricular) on postnatal day 3. Administration of the D1-like antagonist SCH 23390 (0.5-2.0 micrograms) or the D2-like antagonist clebopride (1.0-4.0 micrograms) induced dose-dependent akinesia, catalepsy, and somatosensory neglect in vehicle-treated controls. In contrast, neither antagonist produced deficits in rats depleted of forebrain DA as neonates. However, combined administration of SCH 23390 + clebopride induced similar akinesia, catalepsy, and somatosensory neglect in both controls and DA depleted animals. Animals depleted of DA were more sensitive than controls to the low doses of this combined D1 + D2 antagonism. These results demonstrate that activation of striatal DA receptors remains necessary for unconditioned motor behavior in rats depleted of DA as neonates. However, the specific contributions of D1- and D2-like receptors to these behaviors differ between intact animals and those depleted of DA as neonates. The ability of endogenous DA acting at either D1 or D2 receptors to support spontaneous motor behavior in rats depleted of DA as neonates may contribute to their relative sparing from parkinsonian deficits.

  10. Spherical aberrations of human astigmatic corneas.

    PubMed

    Zhao, Huawei; Dai, Guang-Ming; Chen, Li; Weeber, Henk A; Piers, Patricia A

    2011-11-01

    To evaluate whether the average spherical aberration of human astigmatic corneas is statistically equivalent to human nonastigmatic corneas. Spherical aberrations of 445 astigmatic corneas prior to laser vision correction were retrospectively investigated to determine Zernike coefficients for central corneal areas 6 mm in diameter using CTView (Sarver and Associates). Data were divided into groups according to cylinder power (0.01 to 0.25 diopters [D], 0.26 to 0.75 D, 0.76 to 1.06 D, 1.07 to 1.53 D, 1.54 to 2.00 D, and >2.00 D) and according to age by decade. Spherical aberrations were correlated with age and astigmatic power among groups and the entire population. Statistical analyses were conducted, and P<.05 was considered statistically significant. Mean patient age was 42.6±11 years. Astigmatic corneas had an average astigmatic power of 0.78±0.58 D and mean spherical aberration was 0.25±0.13 μm for the entire population and approximately the same (0.27 μm) for individual groups, ranging from 0.23 to 0.29 μm (P>.05 for all tested groups). Mean spherical aberration of astigmatic corneas was not correlated significantly with cylinder power or age (P>.05). Spherical aberrations are similar to those of nonastigmatic corneas, permitting the use of these additional data in the design of aspheric toric intra-ocular lenses. Copyright 2011, SLACK Incorporated.

  11. Understanding molecular motor walking along a microtubule: a themosensitive asymmetric Brownian motor driven by bubble formation.

    PubMed

    Arai, Noriyoshi; Yasuoka, Kenji; Koishi, Takahiro; Ebisuzaki, Toshikazu; Zeng, Xiao Cheng

    2013-06-12

    The "asymmetric Brownian ratchet model", a variation of Feynman's ratchet and pawl system, is invoked to understand the kinesin walking behavior along a microtubule. The model system, consisting of a motor and a rail, can exhibit two distinct binding states, namely, the random Brownian state and the asymmetric potential state. When the system is transformed back and forth between the two states, the motor can be driven to "walk" in one direction. Previously, we suggested a fundamental mechanism, that is, bubble formation in a nanosized channel surrounded by hydrophobic atoms, to explain the transition between the two states. In this study, we propose a more realistic and viable switching method in our computer simulation of molecular motor walking. Specifically, we propose a thermosensitive polymer model with which the transition between the two states can be controlled by temperature pulses. Based on this new motor system, the stepping size and stepping time of the motor can be recorded. Remarkably, the "walking" behavior observed in the newly proposed model resembles that of the realistic motor protein. The bubble formation based motor not only can be highly efficient but also offers new insights into the physical mechanism of realistic biomolecule motors.

  12. High order aberration and straylight evaluation after cataract surgery with implantation of an aspheric, aberration correcting monofocal intraocular lens

    PubMed Central

    Kretz, Florian T A; Tandogan, Tamer; Khoramnia, Ramin; Auffarth, Gerd U

    2015-01-01

    AIM To evaluate the quality of vision in respect to high order aberrations and straylight perception after implantation of an aspheric, aberration correcting, monofocal intraocular lens (IOL). METHODS Twenty-one patients (34 eyes) aged 50 to 83y underwent cataract surgery with implantation of an aspheric, aberration correcting IOL (Tecnis ZCB00, Abbott Medical Optics). Three months after surgery they were examined for uncorrected (UDVA) and corrected distance visual acuity (CDVA), contrast sensitivity (CS) under photopic and mesopic conditions with and without glare source, ocular high order aberrations (HOA, Zywave II) and retinal straylight (C-Quant). RESULTS Postoperatively, patients achieved a postoperative CDVA of 0.0 logMAR or better in 97.1% of eyes. Mean values of high order abberations were +0.02±0.27 (primary coma components) and -0.04±0.16 (spherical aberration term). Straylight values of the C-Quant were 1.35±0.44 log which is within normal range of age matched phakic patients. The CS measurements under mesopic and photopic conditions in combination with and without glare did not show any statistical significance in the patient group observed (P≥0.28). CONCLUSION The implantation of an aspherical aberration correcting monofocal IOL after cataract surgery resulted in very low residual higher order aberration (HOA) and normal straylight. PMID:26309872

  13. Accommodation to Wavefront Vergence and Chromatic Aberration

    PubMed Central

    Wang, Yinan; Kruger, Philip B.; Li, James S.; Lin, Peter L.; Stark, Lawrence R.

    2011-01-01

    Purpose Longitudinal chromatic aberration (LCA) provides a cue to accommodation with small pupils. However, large pupils increase monochromatic aberrations, which may obscure chromatic blur. In the present study, we examined the effect of pupil size and LCA on accommodation. Methods Accommodation was recorded by infrared optometer while observers (nine normal trichromats) viewed a sinusoidally moving Maltese cross target in a Badal stimulus system. There were two illumination conditions: white (3000 K; 20 cd/m2) and monochromatic (550 nm with 10 nm bandwidth; 20 cd/m2) and two artificial pupil conditions (3 mm and 5.7 mm). Separately, static measurements of wavefront aberration were made with the eye accommodating to targets between 0 and 4 D (COAS, Wavefront Sciences). Results Large individual differences in accommodation to wavefront vergence and to LCA are a hallmark of accommodation. LCA continues to provide a signal at large pupil sizes despite higher levels of monochromatic aberrations. Conclusions Monochromatic aberrations may defend against chromatic blur at high spatial frequencies, but accommodation responds best to optical vergence and to LCA at 3 c/deg where blur from higher order aberrations is less. PMID:21317666

  14. Comparison of Aberrations After Standard and Customized Refractive Surgery

    NASA Astrophysics Data System (ADS)

    Fang, L.; He, X.; Wang, Y.

    2013-09-01

    To detect possible differences in residual wavefront aberrations between standard and customized laser refractive surgery based onmathematical modeling, the residual optical aberrations after conventional and customized laser refractive surgery were compared accordingto the ablation profile with transition zone. The results indicated that ablation profile has a significant impact on the residual aberrations.The amount of residual aberrations for conventional correction is higher than that for customized correction. Additionally, the residualaberrations for high myopia eyes are markedly larger than those for moderate myopia eyes. For a 5 mm pupil, the main residual aberrationterm is coma and yet it is spherical aberration for a 7 mm pupil. When the pupil diameter is the same as optical zone or greater, themagnitudes of residual aberrations is obviously larger than that for a smaller pupil. In addition, the magnitudes of the residual fifth orsixth order aberrations are relatively large, especially secondary coma in a 6 mm pupil and secondary spherical aberration in a 7 mm pupil.Therefore, the customized ablation profile may be superior to the conventional correction even though the transition zone and treatmentdecentration are taken into account. However, the customized ablation profile will still induce significant amount of residual aberrations.

  15. Beta/Gamma Oscillations and Event-Related Potentials Indicate Aberrant Multisensory Processing in Schizophrenia

    PubMed Central

    Balz, Johanna; Roa Romero, Yadira; Keil, Julian; Krebber, Martin; Niedeggen, Michael; Gallinat, Jürgen; Senkowski, Daniel

    2016-01-01

    Recent behavioral and neuroimaging studies have suggested multisensory processing deficits in patients with schizophrenia (SCZ). Thus far, the neural mechanisms underlying these deficits are not well understood. Previous studies with unisensory stimulation have shown altered neural oscillations in SCZ. As such, altered oscillations could contribute to aberrant multisensory processing in this patient group. To test this assumption, we conducted an electroencephalography (EEG) study in 15 SCZ and 15 control participants in whom we examined neural oscillations and event-related potentials (ERPs) in the sound-induced flash illusion (SIFI). In the SIFI multiple auditory stimuli that are presented alongside a single visual stimulus can induce the illusory percept of multiple visual stimuli. In SCZ and control participants we compared ERPs and neural oscillations between trials that induced an illusion and trials that did not induce an illusion. On the behavioral level, SCZ (55.7%) and control participants (55.4%) did not significantly differ in illusion rates. The analysis of ERPs revealed diminished amplitudes and altered multisensory processing in SCZ compared to controls around 135 ms after stimulus onset. Moreover, the analysis of neural oscillations revealed altered 25–35 Hz power after 100 to 150 ms over occipital scalp for SCZ compared to controls. Our findings extend previous observations of aberrant neural oscillations in unisensory perception paradigms. They suggest that altered ERPs and altered occipital beta/gamma band power reflect aberrant multisensory processing in SCZ. PMID:27999553

  16. Prediction error induced motor contagions in human behaviors.

    PubMed

    Ikegami, Tsuyoshi; Ganesh, Gowrishankar; Takeuchi, Tatsuya; Nakamoto, Hiroki

    2018-05-29

    Motor contagions refer to implicit effects on one's actions induced by observed actions. Motor contagions are believed to be induced simply by action observation and cause an observer's action to become similar to the action observed. In contrast, here we report a new motor contagion that is induced only when the observation is accompanied by prediction errors - differences between actions one observes and those he/she predicts or expects. In two experiments, one on whole-body baseball pitching and another on simple arm reaching, we show that the observation of the same action induces distinct motor contagions, depending on whether prediction errors are present or not. In the absence of prediction errors, as in previous reports, participants' actions changed to become similar to the observed action, while in the presence of prediction errors, their actions changed to diverge away from it, suggesting distinct effects of action observation and action prediction on human actions. © 2018, Ikegami et al.

  17. Theoretical investigation of aberrations upon ametropic human eyes

    NASA Astrophysics Data System (ADS)

    Tan, Bo; Chen, Ying-Ling; Lewis, J. W. L.; Baker, Kevin

    2003-11-01

    The human eye aberrations are important for visual acuity and ophthalmic diagnostics and surgical procedures. Reported monochromatic aberration data of the normal 20/20 human eyes are scarce. There exist even fewer reports of the relation between ametropic conditions and aberrations. We theoretically investigate the monochromatic and chromatic aberrations of human eyes for refractive errors of -10 to +10 diopters. Schematic human eye models are employed using optical design software for axial, index, and refractive types of ametropia.

  18. Anterior Corneal, Posterior Corneal, and Lenticular Contributions to Ocular Aberrations.

    PubMed

    Atchison, David A; Suheimat, Marwan; Mathur, Ankit; Lister, Lucas J; Rozema, Jos

    2016-10-01

    To determine the corneal surfaces and lens contributions to ocular aberrations. There were 61 healthy participants with ages ranging from 20 to 55 years and refractions -8.25 diopters (D) to +3.25 D. Anterior and posterior corneal topographies were obtained with an Oculus Pentacam, and ocular aberrations were obtained with an iTrace aberrometer. Raytracing through models of corneas provided total corneal and surface component aberrations for 5-mm-diameter pupils. Lenticular contributions were given as differences between ocular and corneal aberrations. Theoretical raytracing investigated influence of object distance on aberrations. Apart from defocus, the highest aberration coefficients were horizontal astigmatism, horizontal coma, and spherical aberration. Most correlations between lenticular and ocular parameters were positive and significant, with compensation of total corneal aberrations by lenticular aberrations for 5/12 coefficients. Anterior corneal aberrations were approximately three times higher than posterior corneal aberrations and usually had opposite signs. Corneal topographic centers were displaced from aberrometer pupil centers by 0.32 ± 0.19 mm nasally and 0.02 ± 0.16 mm inferiorly; disregarding corneal decentration relative to pupil center was significant for oblique astigmatism, horizontal coma, and horizontal trefoil. An object at infinity, rather than at the image in the anterior cornea, gave incorrect aberration estimates of the posterior cornea. Corneal and lenticular aberration magnitudes are similar, and aberrations of the anterior corneal surface are approximately three times those of the posterior surface. Corneal decentration relative to pupil center has significant effects on oblique astigmatism, horizontal coma, and horizontal trefoil. When estimating component aberrations, it is important to use correct object/image conjugates and heights at surfaces.

  19. Simultaneous correction of large low-order and high-order aberrations with a new deformable mirror technology

    NASA Astrophysics Data System (ADS)

    Rooms, F.; Camet, S.; Curis, J. F.

    2010-02-01

    A new technology of deformable mirror will be presented. Based on magnetic actuators, these deformable mirrors feature record strokes (more than +/- 45μm of astigmatism and focus correction) with an optimized temporal behavior. Furthermore, the development has been made in order to have a large density of actuators within a small clear aperture (typically 52 actuators within a diameter of 9.0mm). We will present the key benefits of this technology for vision science: simultaneous correction of low and high order aberrations, AO-SLO image without artifacts due to the membrane vibration, optimized control, etc. Using recent papers published by Doble, Thibos and Miller, we show the performances that can be achieved by various configurations using statistical approach. The typical distribution of wavefront aberrations (both the low order aberration (LOA) and high order aberration (HOA)) have been computed and the correction applied by the mirror. We compare two configurations of deformable mirrors (52 and 97 actuators) and highlight the influence of the number of actuators on the fitting error, the photon noise error and the effective bandwidth of correction.

  20. The motor way: Clinical implications of understanding and shaping actions with the motor system in autism and drug addiction.

    PubMed

    Casartelli, Luca; Chiamulera, Cristiano

    2016-04-01

    To understand others' minds is crucial for survival; however, it is quite puzzling how access to others' minds can be--to some extent--direct and not necessarily mediated by conceptual reasoning. Recent advances in neuroscience have led to hypothesize a role for motor circuits not only in controlling the elementary physical features of movement (e.g., force, direction, and amplitude), but also in understanding and shaping human behavior. The concept of "motor cognition" refers to these aspects, and neurophysiological, neuroimaging, and behavioral studies in human and nonhuman primates support this view. From a clinical perspective, motor cognition represents a challenge in several domains. A thorough investigation of the neural mechanisms mediating motor action/intention understanding and automatized/compulsive behaviors seems to be a promising way to tackle a range of neurodevelopmental and drug-related disorders. On the one hand, anomalies in motor cognition may have cascade effects on social functioning in individuals with autism spectrum disorder (ASD); on the other, motor cognition may help explain the pathophysiology of drug-seeking and drug-taking behaviors in the most severe phase of drug addiction (i.e., see drug dependence, motor low-order cue reactivity). This may represent a promising approach that could improve the efficacy of rehabilitative interventions. The only way to shed light on multifactorial disorders such as ASD and drug addiction is through the investigation of their multiple factors. This motor way can promote new theoretical and experimental perspectives that would help bridge the gap between the basic neuroscience approach and clinical practice.

  1. The lifespan trajectory of neural oscillatory activity in the motor system.

    PubMed

    Heinrichs-Graham, Elizabeth; McDermott, Timothy J; Mills, Mackenzie S; Wiesman, Alex I; Wang, Yu-Ping; Stephen, Julia M; Calhoun, Vince D; Wilson, Tony W

    2018-04-01

    Numerous studies connect beta oscillations in the motor cortices to volitional movement, and beta is known to be aberrant in multiple movement disorders. However, the dynamic interplay between these beta oscillations, motor performance, and spontaneous beta power (e.g., during rest) in the motor cortices remains unknown. This study utilized magnetoencephalography (MEG) to investigate these three parameters and their lifespan trajectory in 57 healthy participants aged 9-75 years old. Movement-related beta activity was imaged using a beamforming approach, and voxel time series data were extracted from the peak voxels in the primary motor cortices. Our results indicated that spontaneous beta power during rest followed a quadratic lifespan trajectory, while movement-related beta oscillations linearly increased with age. Follow-on analyses showed that spontaneous beta power and the beta minima during movement, together, significantly predicted task performance above and beyond the effects of age. These data are the first to show lifespan trajectories among measures of beta activity in the motor cortices, and suggest that the healthy brain compensates for age-related increases in spontaneous beta activity by increasing the strength of beta oscillations within the motor cortices which, when successful, enables normal motor performance into later life. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. A Synergetic Approach to Describe the Stability and Variability of Motor Behavior

    NASA Astrophysics Data System (ADS)

    Witte, Kersttn; Bock, Holger; Storb, Ulrich; Blaser, Peter

    At the beginning of the 20th century, the Russian physiologist and biomechanist Bernstein developed his cyclograms, in which he showed in the non-repetition of the same movement under constant conditions. We can also observe this phenomenon when we analyze several cyclic sports movements. For example, we investigated the trajectories of single joints and segments of the body in breaststroke, walking, and running. The problem of the stability and variability of movement, and the relation between the two, cannot be satisfactorily tackled by means of linear methods. Thus, several authors (Turvey, 1977; Kugler et al., 1980; Haken et al., 1985; Schöner et al., 1986; Mitra et al., 1997; Kay et al., 1991; Ganz et al., 1996; Schöllhorn, 1999) use nonlinear models to describe human movement. These models and approaches have shown that nonlinear theories of complex systems provide a new understanding of the stability and variability of motor control. The purpose of this chapter is a presentation of a common synergetic model of motor behavior and its application to foot tapping, walking, and running.

  3. Autistic-spectrum disorders in Down syndrome: further delineation and distinction from other behavioral abnormalities.

    PubMed

    Carter, John C; Capone, George T; Gray, Robert M; Cox, Christiane S; Kaufmann, Walter E

    2007-01-05

    The present study extends our previous work characterizing the behavioral features of autistic-spectrum disorder (ASD) in Down syndrome (DS) using the Aberrant Behavior Checklist (ABC) and Autism Behavior Checklist (AutBehav). We examined which specific behaviors distinguished the behavioral phenotype of DS + ASD from other aberrant behavior disorders in DS, by determining the relative contribution of ABC and AutBehav subscales and items to the diagnosis of ASD. A total of 127 subjects (aged 2-24 years; mean age: 8.4 years; approximately 70% male), comprising: a cohort of 64 children and adolescents with DS and co-morbid ASD (DS + ASD), 19 with DS and stereotypic movement disorder (DS + SMD), 18 with DS and disruptive behaviors (DS + DB), and 26 with DS and no co-morbid behavior disorders (DS + none) were examined using the aforementioned measures of aberrant behavior. We found that subjects with DS + ASD showed the most severe aberrant behavior, especially stereotypy compared to DS + none and lethargy/social withdrawal and relating problems compared to DS + SMD. Specifically, relatively simple stereotypic behavior differentiated DS + ASD from DS + DB, whereas odd/bizarre stereotypic and anxious behavior characterized DS + ASD relative to DS + SMD and DS + none. Additionally, in a subset of subjects with DS + ASD and anxiety, social withdrawal was particularly pronounced. Overall, our findings indicate that a diagnosis of DS + ASD represents a distinctive set of aberrant behaviors marked by characteristic odd/bizarre stereotypic behavior, anxiety, and social withdrawal.

  4. Mutant TDP-43 within motor neurons drives disease onset but not progression in amyotrophic lateral sclerosis.

    PubMed

    Ditsworth, Dara; Maldonado, Marcus; McAlonis-Downes, Melissa; Sun, Shuying; Seelman, Amanda; Drenner, Kevin; Arnold, Eveline; Ling, Shuo-Chien; Pizzo, Donald; Ravits, John; Cleveland, Don W; Da Cruz, Sandrine

    2017-06-01

    Mutations in TDP-43 cause amyotrophic lateral sclerosis (ALS), a fatal paralytic disease characterized by degeneration and premature death of motor neurons. The contribution of mutant TDP-43-mediated damage within motor neurons was evaluated using mice expressing a conditional allele of an ALS-causing TDP-43 mutant (Q331K) whose broad expression throughout the central nervous system mimics endogenous TDP-43. TDP-43 Q331K mice develop age- and mutant-dependent motor deficits from degeneration and death of motor neurons. Cre-recombinase-mediated excision of the TDP-43 Q331K gene from motor neurons is shown to delay onset of motor symptoms and appearance of TDP-43-mediated aberrant nuclear morphology, and abrogate subsequent death of motor neurons. However, reduction of mutant TDP-43 selectively in motor neurons did not prevent age-dependent degeneration of axons and neuromuscular junction loss, nor did it attenuate astrogliosis or microgliosis. Thus, disease mechanism is non-cell autonomous with mutant TDP-43 expressed in motor neurons determining disease onset but progression defined by mutant acting within other cell types.

  5. Aberration corrected STEM by means of diffraction gratings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Linck, Martin; Ercius, Peter A.; Pierce, Jordan S.

    In the past 15 years, the advent of aberration correction technology in electron microscopy has enabled materials analysis on the atomic scale. This is made possible by precise arrangements of multipole electrodes and magnetic solenoids to compensate the aberrations inherent to any focusing element of an electron microscope. In this paper, we describe an alternative method to correct for the spherical aberration of the objective lens in scanning transmission electron microscopy (STEM) using a passive, nanofabricated diffractive optical element. This holographic device is installed in the probe forming aperture of a conventional electron microscope and can be designed to removemore » arbitrarily complex aberrations from the electron's wave front. In this work, we show a proof-of-principle experiment that demonstrates successful correction of the spherical aberration in STEM by means of such a grating corrector (GCOR). Our GCOR enables us to record aberration-corrected high-resolution high-angle annular dark field (HAADF-) STEM images, although yet without advancement in probe current and resolution. Finally, improvements in this technology could provide an economical solution for aberration-corrected high-resolution STEM in certain use scenarios.« less

  6. Aberration corrected STEM by means of diffraction gratings

    DOE PAGES

    Linck, Martin; Ercius, Peter A.; Pierce, Jordan S.; ...

    2017-06-12

    In the past 15 years, the advent of aberration correction technology in electron microscopy has enabled materials analysis on the atomic scale. This is made possible by precise arrangements of multipole electrodes and magnetic solenoids to compensate the aberrations inherent to any focusing element of an electron microscope. In this paper, we describe an alternative method to correct for the spherical aberration of the objective lens in scanning transmission electron microscopy (STEM) using a passive, nanofabricated diffractive optical element. This holographic device is installed in the probe forming aperture of a conventional electron microscope and can be designed to removemore » arbitrarily complex aberrations from the electron's wave front. In this work, we show a proof-of-principle experiment that demonstrates successful correction of the spherical aberration in STEM by means of such a grating corrector (GCOR). Our GCOR enables us to record aberration-corrected high-resolution high-angle annular dark field (HAADF-) STEM images, although yet without advancement in probe current and resolution. Finally, improvements in this technology could provide an economical solution for aberration-corrected high-resolution STEM in certain use scenarios.« less

  7. Cortical dynamics and subcortical signatures of motor-language coupling in Parkinson's disease.

    PubMed

    Melloni, Margherita; Sedeño, Lucas; Hesse, Eugenia; García-Cordero, Indira; Mikulan, Ezequiel; Plastino, Angelo; Marcotti, Aida; López, José David; Bustamante, Catalina; Lopera, Francisco; Pineda, David; García, Adolfo M; Manes, Facundo; Trujillo, Natalia; Ibáñez, Agustín

    2015-07-08

    Impairments of action language have been documented in early stage Parkinson's disease (EPD). The action-sentence compatibility effect (ACE) paradigm has revealed that EPD involves deficits to integrate action-verb processing and ongoing motor actions. Recent studies suggest that an abolished ACE in EPD reflects a cortico-subcortical disruption, and recent neurocognitive models highlight the role of the basal ganglia (BG) in motor-language coupling. Building on such breakthroughs, we report the first exploration of convergent cortical and subcortical signatures of ACE in EPD patients and matched controls. Specifically, we combined cortical recordings of the motor potential, functional connectivity measures, and structural analysis of the BG through voxel-based morphometry. Relative to controls, EPD patients exhibited an impaired ACE, a reduced motor potential, and aberrant frontotemporal connectivity. Furthermore, motor potential abnormalities during the ACE task were predicted by overall BG volume and atrophy. These results corroborate that motor-language coupling is mainly subserved by a cortico-subcortical network including the BG as a key hub. They also evince that action-verb processing may constitute a neurocognitive marker of EPD. Our findings suggest that research on the relationship between language and motor domains is crucial to develop models of motor cognition as well as diagnostic and intervention strategies.

  8. Aberration correction for charged particle lithography

    NASA Astrophysics Data System (ADS)

    Munro, Eric; Zhu, Xieqing; Rouse, John A.; Liu, Haoning

    2001-12-01

    At present, the throughput of projection-type charge particle lithography systems, such as PREVAIL and SCALPEL, is limited primarily by the combined effects of field curvature in the projection lenses and Coulomb interaction in the particle beam. These are fundamental physical limitations, inherent in charged particle optics, so there seems little scope for significantly improving the design of such systems, using conventional rotationally symmetric electron lenses. This paper explores the possibility of overcoming the field aberrations of round electron lense, by using a novel aberration corrector, proposed by Professor H. Rose of University of Darmstadt, called a hexapole planator. In this scheme, a set of round lenses is first used to simultaneously correct distortion and coma. The hexapole planator is then used to correct the field curvature and astigmatism, and to create a negative spherical aberration. The size of the transfer lenses around the planator can then be adjusted to zero the residual spherical aberration. In a way, an electron optical projection system is obtained that is free of all primary geometrical aberrations. In this paper, the feasibility of this concept has been studied with a computer simulation. The simulations verify that this scheme can indeed work, for both electrostatic and magnetic projection systems. Two design studies have been carried out. The first is for an electrostatic system that could be used for ion beam lithography, and the second is for a magnetic projection system for electron beam lithography. In both cases, designs have been achieved in which all primary third-order geometrical aberrations are totally eliminated.

  9. Aberration Compensation in Aplanatic Solid Immersion Lens Microscopy

    DTIC Science & Technology

    2013-11-08

    model and ray tracing software ( Zemax ) to understand how much aberrations are in the system and how much can be compensated by the DM. Subsequently...aberration. Table 2 shows the Zemax simulation on this particular case. With aberration compensation, the finest resolvable group is at 252 nm

  10. Obesity Reduces Cognitive and Motor Functions across the Lifespan

    PubMed Central

    Wang, Chuanming; Chan, John S. Y.; Ren, Lijie; Yan, Jin H.

    2016-01-01

    Due to a sedentary lifestyle, more and more people are becoming obese nowadays. In addition to health-related problems, obesity can also impair cognition and motor performance. Previous results have shown that obesity mainly affects cognition and motor behaviors through altering brain functions and musculoskeletal system, respectively. Many factors, such as insulin/leptin dysregulation and inflammation, mediate the effect of obesity and cognition and motor behaviors. Substantial evidence has suggested exercise to be an effective way to improve obesity and related cognitive and motor dysfunctions. This paper aims to discuss the association of obesity with cognition and motor behaviors and its underlying mechanisms. Following this, mechanisms of exercise to improve obesity-related dysfunctions are described. Finally, implications and future research direction are raised. PMID:26881095

  11. Obesity Reduces Cognitive and Motor Functions across the Lifespan.

    PubMed

    Wang, Chuanming; Chan, John S Y; Ren, Lijie; Yan, Jin H

    2016-01-01

    Due to a sedentary lifestyle, more and more people are becoming obese nowadays. In addition to health-related problems, obesity can also impair cognition and motor performance. Previous results have shown that obesity mainly affects cognition and motor behaviors through altering brain functions and musculoskeletal system, respectively. Many factors, such as insulin/leptin dysregulation and inflammation, mediate the effect of obesity and cognition and motor behaviors. Substantial evidence has suggested exercise to be an effective way to improve obesity and related cognitive and motor dysfunctions. This paper aims to discuss the association of obesity with cognition and motor behaviors and its underlying mechanisms. Following this, mechanisms of exercise to improve obesity-related dysfunctions are described. Finally, implications and future research direction are raised.

  12. Neural correlates of behavior therapy for Tourette's disorder.

    PubMed

    Deckersbach, Thilo; Chou, Tina; Britton, Jennifer C; Carlson, Lindsay E; Reese, Hannah E; Siev, Jedidiah; Scahill, Lawrence; Piacentini, John C; Woods, Douglas W; Walkup, John T; Peterson, Alan L; Dougherty, Darin D; Wilhelm, Sabine

    2014-12-30

    Tourette's disorder, also called Tourette syndrome (TS), is characterized by motor and vocal tics that can cause significant impairment in daily functioning. Tics are believed to be due to failed inhibition of both associative and motor cortico-striato-thalamo-cortical pathways. Comprehensive Behavioral Intervention for Tics (CBIT), which is an extension of Habit Reversal Therapy (HRT), teaches patients to become more aware of sensations that reliably precede tics (premonitory urges) and to initiate competing movements that inhibit the occurrence of tics. In this study, we used functional magnetic resonance imaging (fMRI) to investigate the neural changes associated with CBIT treatment in subjects with TS. Eight subjects with TS were matched with eight healthy controls in gender, education, age, and handedness. Subjects completed the Visuospatial Priming (VSP) task, a measure of response inhibition, during fMRI scanning before and after CBIT treatment (or waiting period for controls). For TS subjects, we found a significant decrease in striatal (putamen) activation from pre- to post-treatment. Change in VSP task-related activation from pre- to post-treatment in Brodmann's area 47 (the inferior frontal gyrus) was negatively correlated with changes in tic severity. CBIT may promote normalization of aberrant cortico-striato-thalamo-cortical associative and motor pathways in individuals with TS. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  13. Time-varying motor control of autotomized leopard gecko tails: multiple inputs and behavioral modulation.

    PubMed

    Higham, Timothy E; Russell, Anthony P

    2012-02-01

    Autotomy (voluntary loss of an appendage) is common among diverse groups of vertebrates and invertebrates, and much attention has been given to ecological and developmental aspects of tail autotomy in lizards. Although most studies have focused on the ramifications for the lizard (behavior, biomechanics, energetics, etc.), the tail itself can exhibit interesting behaviors once segregated from the body. For example, recent work highlighted the ability of leopard gecko tails to jump and flip, in addition to being able to swing back and forth. Little is known, however, about the control mechanisms underlying these movements. Using electromyography, we examined the time-varying in vivo motor patterns at four sites (two proximal and two distal) in the tail of the leopard gecko, Eublepharis macularius, following autotomy. Using these data we tested the hypothesis that the disparity in movements results simply from overlapping pattern generators within the tail. We found that burst duration, but not cycle duration, of the rhythmic swings reached a plateau at approximately 150 s following autotomy. This is likely because of physiological changes related to muscle fatigue and ischemia. For flips and jumps, burst and cycle duration exhibited no regular pattern. The coefficient of variation in motor patterns was significantly greater for jumps and flips than for rhythmic swings. This supports the conclusion that the different tail behaviors do not stem from overlapping pattern generators, but that they rely upon independent neural circuits. The signal controlling jumps and flips may be modified by sensory information from the environment. Finally, we found that jumps and flips are initiated using relatively synchronous activity between the two sides of the tail. In contrast, alternating activation of the right and left sides of the tail result in rhythmic swings. The mechanism underlying this change in tail behavior is comparable to locomotor gait changes in vertebrates.

  14. D2 receptor genotype and striatal dopamine signaling predict motor cortical activity and behavior in humans.

    PubMed

    Fazio, Leonardo; Blasi, Giuseppe; Taurisano, Paolo; Papazacharias, Apostolos; Romano, Raffaella; Gelao, Barbara; Ursini, Gianluca; Quarto, Tiziana; Lo Bianco, Luciana; Di Giorgio, Annabella; Mancini, Marina; Popolizio, Teresa; Rubini, Giuseppe; Bertolino, Alessandro

    2011-02-14

    Pre-synaptic D2 receptors regulate striatal dopamine release and DAT activity, key factors for modulation of motor pathways. A functional SNP of DRD2 (rs1076560 G>T) is associated with alternative splicing such that the relative expression of D2S (mainly pre-synaptic) vs. D2L (mainly post-synaptic) receptor isoforms is decreased in subjects with the T allele with a putative increase of striatal dopamine levels. To evaluate how DRD2 genotype and striatal dopamine signaling predict motor cortical activity and behavior in humans, we have investigated the association of rs1076560 with BOLD fMRI activity during a motor task. To further evaluate the relationship of this circuitry with dopamine signaling, we also explored the correlation between genotype based differences in motor brain activity and pre-synaptic striatal DAT binding measured with [(123)I] FP-CIT SPECT. Fifty healthy subjects, genotyped for DRD2 rs1076560 were studied with BOLD-fMRI at 3T while performing a visually paced motor task with their right hand; eleven of these subjects also underwent [(123)I]FP-CIT SPECT. SPM5 random-effects models were used for statistical analyses. Subjects carrying the T allele had greater BOLD responses in left basal ganglia, thalamus, supplementary motor area, and primary motor cortex, whose activity was also negatively correlated with reaction time at the task. Moreover, left striatal DAT binding and activity of left supplementary motor area were negatively correlated. The present results suggest that DRD2 genetic variation was associated with focusing of responses in the whole motor network, in which activity of predictable nodes was correlated with reaction time and with striatal pre-synaptic dopamine signaling. Our results in humans may help shed light on genetic risk for neurobiological mechanisms involved in the pathophysiology of disorders with dysregulation of striatal dopamine like Parkinson's disease. Copyright © 2010 Elsevier Inc. All rights reserved.

  15. A Cholinergic-Regulated Circuit Coordinates the Maintenance and Bi-Stable States of a Sensory-Motor Behavior during Caenorhabditis elegans Male Copulation

    PubMed Central

    Liu, Yishi; LeBeouf, Brigitte; Guo, Xiaoyan; Correa, Paola A.; Gualberto, Daisy G.; Lints, Robyn; Garcia, L. Rene

    2011-01-01

    Penetration of a male copulatory organ into a suitable mate is a conserved and necessary behavioral step for most terrestrial matings; however, the detailed molecular and cellular mechanisms for this distinct social interaction have not been elucidated in any animal. During mating, the Caenorhabditis elegans male cloaca is maintained over the hermaphrodite's vulva as he attempts to insert his copulatory spicules. Rhythmic spicule thrusts cease when insertion is sensed. Circuit components consisting of sensory/motor neurons and sex muscles for these steps have been previously identified, but it was unclear how their outputs are integrated to generate a coordinated behavior pattern. Here, we show that cholinergic signaling between the cloacal sensory/motor neurons and the posterior sex muscles sustains genital contact between the sexes. Simultaneously, via gap junctions, signaling from these muscles is transmitted to the spicule muscles, thus coupling repeated spicule thrusts with vulval contact. To transit from rhythmic to sustained muscle contraction during penetration, the SPC sensory-motor neurons integrate the signal of spicule's position in the vulva with inputs from the hook and cloacal sensilla. The UNC-103 K+ channel maintains a high excitability threshold in the circuit, so that sustained spicule muscle contraction is not stimulated by fewer inputs. We demonstrate that coordination of sensory inputs and motor outputs used to initiate, maintain, self-monitor, and complete an innate behavior is accomplished via the coupling of a few circuit components. PMID:21423722

  16. Prospective associations between measures of gross and fine motor coordination in infants and objectively measured physical activity and sedentary behavior in childhood

    PubMed Central

    Sánchez, Guillermo F López; Williams, Genevieve; Aggio, Daniel; Vicinanza, Domenico; Stubbs, Brendon; Kerr, Catherine; Johnstone, James; Roberts, Justine; Smith, Lee

    2017-01-01

    Abstract One important determinant of childhood physical activity and sedentary behavior may be that of motor development in infancy. The present analyses aimed to investigate whether gross and fine motor delays in infants were associated with objective and self-reported activity in childhood. Data were from the UK Millennium Cohort Study, a prospective cohort study, involving UK children born on or around the millennium (September 2000 and January 2002). When children were 9 months old, parents reported children's fine and gross motor-coordination, and at 7 years, sports club attendance and daily TV viewing time. Children's physical activity was measured using accelerometers at 7 years. Adjusted regression models were used to examine associations between delayed motor development and accelerometry measured moderate-to-vigorous physical activity and sedentary behavior, and parent-reported sport club attendance and TV viewing time. In this sample (n = 13,021), gross motor delay in infancy was associated with less time in moderate-to-vigorous physical activity (B −5.0 95% confidence interval [CI] −6.8, −3.2) and more time sedentary (B 13.5 95% CI 9.3, 17.8) in childhood. Gross and fine motor delays during infancy were associated with a reduced risk of having high attendance at sports clubs in childhood (both relative risk [RR] 0.7, 95% CI 0.6, 0.9). Fine motor delays, but not gross delays, were also associated with an increased risk of having high TV viewing time (RR 1.3 95% CI 1.0, 1.6). Findings from the present study suggest that delays in motor development in infancy are associated with physical activity and sedentary time in childhood. PMID:29145249

  17. Prospective associations between measures of gross and fine motor coordination in infants and objectively measured physical activity and sedentary behavior in childhood.

    PubMed

    Sánchez, Guillermo F López; Williams, Genevieve; Aggio, Daniel; Vicinanza, Domenico; Stubbs, Brendon; Kerr, Catherine; Johnstone, James; Roberts, Justin; Smith, Lee

    2017-11-01

    One important determinant of childhood physical activity and sedentary behavior may be that of motor development in infancy. The present analyses aimed to investigate whether gross and fine motor delays in infants were associated with objective and self-reported activity in childhood. Data were from the UK Millennium Cohort Study, a prospective cohort study, involving UK children born on or around the millennium (September 2000 and January 2002). When children were 9 months old, parents reported children's fine and gross motor-coordination, and at 7 years, sports club attendance and daily TV viewing time. Children's physical activity was measured using accelerometers at 7 years. Adjusted regression models were used to examine associations between delayed motor development and accelerometry measured moderate-to-vigorous physical activity and sedentary behavior, and parent-reported sport club attendance and TV viewing time. In this sample (n = 13,021), gross motor delay in infancy was associated with less time in moderate-to-vigorous physical activity (B -5.0 95% confidence interval [CI] -6.8, -3.2) and more time sedentary (B 13.5 95% CI 9.3, 17.8) in childhood. Gross and fine motor delays during infancy were associated with a reduced risk of having high attendance at sports clubs in childhood (both relative risk [RR] 0.7, 95% CI 0.6, 0.9). Fine motor delays, but not gross delays, were also associated with an increased risk of having high TV viewing time (RR 1.3 95% CI 1.0, 1.6). Findings from the present study suggest that delays in motor development in infancy are associated with physical activity and sedentary time in childhood.

  18. Studies in Motor Behavior: 75 Years of Research in Motor Development, Learning, and Control

    ERIC Educational Resources Information Center

    Ulrich, Beverly D.; Reeve, T. Gilmour

    2005-01-01

    Research focused on human motor development, learning, and control has been a prominent feature in the Research Quarterly for Exercise and Sport (RQES) since it was first published in 1930. The purpose of this article is to provide an overview of the papers in the RQES that demonstrate the journal's contributions to the study of motor development,…

  19. Human eyes do not need monochromatic aberrations for dynamic accommodation.

    PubMed

    Bernal-Molina, Paula; Marín-Franch, Iván; Del Águila-Carrasco, Antonio J; Esteve-Taboada, Jose J; López-Gil, Norberto; Kruger, Philip B; Montés-Micó, Robert

    2017-09-01

    To determine if human accommodation uses the eye's own monochromatic aberrations to track dynamic accommodative stimuli. Wavefront aberrations were measured while subjects monocularly viewed a monochromatic Maltese cross moving sinusoidally around 2D of accommodative demand with 1D amplitude at 0.2 Hz. The amplitude and phase (delay) of the accommodation response were compared to the actual vergence of the stimulus to obtain gain and temporal phase, calculated from wavefront aberrations recorded over time during experimental trials. The tested conditions were as follows: Correction of all the subject's aberrations except defocus (C); Correction of all the subject's aberrations except defocus and habitual second-order astigmatism (AS); Correction of all the subject's aberrations except defocus and odd higher-order aberrations (HOAs); Correction of all the subject's aberrations except defocus and even HOAs (E); Natural aberrations of the subject's eye, i.e., the adaptive-optics system only corrected the optical system's aberrations (N); Correction of all the subject's aberrations except defocus and fourth-order spherical aberration (SA). The correction was performed at 20 Hz and each condition was repeated six times in randomised order. Average gain (±2 standard errors of the mean) varied little across conditions; between 0.55 ± 0.06 (SA), and 0.62 ± 0.06 (AS). Average phase (±2 standard errors of the mean) also varied little; between 0.41 ± 0.02 s (E), and 0.47 ± 0.02 s (O). After Bonferroni correction, no statistically significant differences in gain or phase were found in the presence of specific monochromatic aberrations or in their absence. These results show that the eye's monochromatic aberrations are not necessary for accommodation to track dynamic accommodative stimuli. © 2017 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.

  20. Transcriptomics of aged Drosophila motor neurons reveals a matrix metalloproteinase that impairs motor function.

    PubMed

    Azpurua, Jorge; Mahoney, Rebekah E; Eaton, Benjamin A

    2018-04-01

    The neuromuscular junction (NMJ) is responsible for transforming nervous system signals into motor behavior and locomotion. In the fruit fly Drosophila melanogaster, an age-dependent decline in motor function occurs, analogous to the decline experienced in mice, humans, and other mammals. The molecular and cellular underpinnings of this decline are still poorly understood. By specifically profiling the transcriptome of Drosophila motor neurons across age using custom microarrays, we found that the expression of the matrix metalloproteinase 1 (dMMP1) gene reproducibly increased in motor neurons in an age-dependent manner. Modulation of physiological aging also altered the rate of dMMP1 expression, validating dMMP1 expression as a bona fide aging biomarker for motor neurons. Temporally controlled overexpression of dMMP1 specifically in motor neurons was sufficient to induce deficits in climbing behavior and cause a decrease in neurotransmitter release at neuromuscular synapses. These deficits were reversible if the dMMP1 expression was shut off again immediately after the onset of motor dysfunction. Additionally, repression of dMMP1 enzymatic activity via overexpression of a tissue inhibitor of metalloproteinases delayed the onset of age-dependent motor dysfunction. MMPs are required for proper tissue architecture during development. Our results support the idea that matrix metalloproteinase 1 is acting as a downstream effector of antagonistic pleiotropy in motor neurons and is necessary for proper development, but deleterious when reactivated at an advanced age. © 2018 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  1. Third-rank chromatic aberrations of electron lenses.

    PubMed

    Liu, Zhixiong

    2018-02-01

    In this paper the third-rank chromatic aberration coefficients of round electron lenses are analytically derived and numerically calculated by Mathematica. Furthermore, the numerical results are cross-checked by the differential algebraic (DA) method, which verifies that all the formulas for the third-rank chromatic aberration coefficients are completely correct. It is hoped that this work would be helpful for further chromatic aberration correction in electron microscopy. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. A Recommended New Approach on Motorization Ratio Calculations of Stepper Motors

    NASA Technical Reports Server (NTRS)

    Nalbandian, Ruben; Blais, Thierry; Horth, Richard

    2014-01-01

    Stepper motors are widely used on most spacecraft mechanisms requiring repeatable and reliable performance. The unique detent torque characteristics of these type of motors makes them behave differently when subjected to low duty cycle excitations where the applied driving pulses are only energized for a fraction of the pulse duration. This phenomenon is even more pronounced in discrete permanent magnet stepper motors used in the space industry. While the inherent high detent properties of discrete permanent magnets provide desirable unpowered holding performance characteristics, it results in unique behavior especially in low duty cycles. Notably, the running torque reduces quickly to the unpowered holding torque when the duty cycle is reduced. The space industry's accepted methodology of calculating the Motorization Ratio (or Torque Margin) is more applicable to systems where the power is continuously applied to the motor coils like brushless DC motors where the cogging torques are low enough not to affect the linear performance of the motors as a function of applied current. This paper summarizes the theoretical and experimental studies performed on a number of space qualified motors under different pulse rates and duty cycles. It is the intention of this paper to introduce a new approach to calculate the Motorization Ratios for discrete permanent magnet steppers under all full and partial duty cycle regimes. The recommended approach defines two distinct relationships to calculate the Motorization Ratio for 100 percent duty cycle and partial duty cycle, when the motor detent (unpowered holding torque) is the main contributor to holding position. These two computations reflect accurately the stepper motor physical behavior as a function of the command phase (ON versus OFF times of the pulses), pointing out how the torque contributors combine. Important points highlighted under this study are the torque margin computations, in particular for well characterized

  3. Functional connectivity between somatosensory and motor brain areas predicts individual differences in motor learning by observing.

    PubMed

    McGregor, Heather R; Gribble, Paul L

    2017-08-01

    Action observation can facilitate the acquisition of novel motor skills; however, there is considerable individual variability in the extent to which observation promotes motor learning. Here we tested the hypothesis that individual differences in brain function or structure can predict subsequent observation-related gains in motor learning. Subjects underwent an anatomical MRI scan and resting-state fMRI scans to assess preobservation gray matter volume and preobservation resting-state functional connectivity (FC), respectively. On the following day, subjects observed a video of a tutor adapting her reaches to a novel force field. After observation, subjects performed reaches in a force field as a behavioral assessment of gains in motor learning resulting from observation. We found that individual differences in resting-state FC, but not gray matter volume, predicted postobservation gains in motor learning. Preobservation resting-state FC between left primary somatosensory cortex and bilateral dorsal premotor cortex, primary motor cortex, and primary somatosensory cortex and left superior parietal lobule was positively correlated with behavioral measures of postobservation motor learning. Sensory-motor resting-state FC can thus predict the extent to which observation will promote subsequent motor learning. NEW & NOTEWORTHY We show that individual differences in preobservation brain function can predict subsequent observation-related gains in motor learning. Preobservation resting-state functional connectivity within a sensory-motor network may be used as a biomarker for the extent to which observation promotes motor learning. This kind of information may be useful if observation is to be used as a way to boost neuroplasticity and sensory-motor recovery for patients undergoing rehabilitation for diseases that impair movement such as stroke. Copyright © 2017 the American Physiological Society.

  4. The Distribution of Chromosomal Aberrations in Human Cells Predicted by a Generalized Time-Dependent Model of Radiation-Induced Formation of Aberrations

    NASA Technical Reports Server (NTRS)

    Ponomarev, Artem L.; George, K.; Cucinotta, F. A.

    2011-01-01

    New experimental data show how chromosomal aberrations for low- and high-LET radiation are dependent on DSB repair deficiencies in wild-type, AT and NBS cells. We simulated the development of chromosomal aberrations in these cells lines in a stochastic track-structure-dependent model, in which different cells have different kinetics of DSB repair. We updated a previously formulated model of chromosomal aberrations, which was based on a stochastic Monte Carlo approach, to consider the time-dependence of DSB rejoining. The previous version of the model had an assumption that all DSBs would rejoin, and therefore we called it a time-independent model. The chromosomal-aberrations model takes into account the DNA and track structure for low- and high-LET radiations, and provides an explanation and prediction of the statistics of rare and more complex aberrations. We compared the program-simulated kinetics of DSB rejoining to the experimentally-derived bimodal exponential curves of the DSB kinetics. We scored the formation of translocations, dicentrics, acentric and centric rings, deletions, and inversions. The fraction of DSBs participating in aberrations was studied in relation to the rejoining time. Comparisons of simulated dose dependence for simple aberrations to the experimental dose-dependence for HF19, AT and NBS cells will be made.

  5. Traffic collisions between electric mobility devices (wheelchairs) and motor vehicles: Accidents, hubris, or self-destructive behavior?

    PubMed

    LaBan, Myron M; Nabity, Thomas S

    2010-07-01

    This study had its genesis in a personally observed collision between a motor vehicle and a motorized wheelchair (electric mobility device) on a busy street in the middle of the block at an unmarked crossing. To the observer, at the time, this appeared to be a suicidal act. This investigation was initiated to both delineate the number of these crashes nationally and understand this phenomena as a potentially planned act of self-destruction. An initial survey of police reports was immediately frustrated by an inability to separate motor vehicle and electric mobility device collisions from the much larger group that involved ambulatory citizens because both types were classified together as "pedestrian" accidents. Instead, the search engine NexisLexis was used to identify 107 newspaper articles each of which described a motor vehicle and electric mobility device accident. In the motor vehicle and electric mobility device collisions, men predominated women (3:1 ratio) with an average age of 56 yrs. Sixty of these accidents were fatal. Ninety-four percent involved an electric mobility device and 6% a manual wheelchair. In 50% of the cases, the motor vehicle was a truck, van, or sport utility vehicle. Fifty percent occurred at dusk or dawn or at night. The electric mobility device occupant was cited as the guilty party in 39% of the cases and the driver of the motor vehicle in 27%. Twenty percent were unwitnessed hit-and-run accidents, whereas "no fault" was found in 8% of the cases. Although many accidents do happen by chance, when an electric mobility device operator openly challenges busy traffic by attempting to traverse it in the middle of the block at an unmarked crossing, predisposing psychosocial factors must also be considered. Hubris or premeditated self-destructive behavior or both need to be explored as preeminent issues with reference to the prodromal of the "accident process."

  6. Harmonic oscillator states in aberration optics

    NASA Technical Reports Server (NTRS)

    Wolf, Kurt Bernardo

    1993-01-01

    The states of the three-dimensional quantum harmonic oscillator classify optical aberrations of axis-symmetric systems due to the isomorphism between the two mathematical structures. Cartesian quanta and angular momentum classifications have their corresponding aberration classifications. The operation of concatenation of optical elements introduces a new operation between harmonic oscillator states.

  7. Behavioral, cognitive, and motor performance and physical development of five-year-old children who were born after intracytoplasmic sperm injection with the use of testicular sperm.

    PubMed

    Meijerink, Aukje M; Ramos, Liliana; Janssen, Anjo J W M; Maas-van Schaaijk, Nienke M; Meissner, Andreas; Repping, Sjoerd; Mochtar, Monique H; Braat, Didi D M; Fleischer, Kathrin

    2016-12-01

    To evaluate at the age of 5 years the behavioral, cognitive, and motor performance and physical development of children born after testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI). A prospective longitudinal cohort study. Two university medical centers. A total of 103 5-year-olds who were born after TESE-ICSI. The follow-up of the children was performed by questionnaires at birth and again at 1 year and at 4 years of age. Five-year-old children were invited for individual assessment. Behavioral performance was assessed with the use of the Child Behavior Checklist for parents and teachers. Cognitive performance was assessed with the use of the Dutch Wechsler Preschool and Primary Scale of Intelligence test, 3rd version. Motor performance was assessed with the use of the Dutch Movement Assessment Battery for Children, 2nd version. Physical development was assessed by means of physical examination and medical history. Behavioral, cognitive, and motor performance and physical development. Eighty-nine children were completely assessed, and 14 were partially assessed at the age of 5 years. The 5-year-old cohort assessed significantly better on behavioral and cognitive performance and significantly worse on motor performance-but still in the normal range-compared with the theoretic distribution in the general population. Four children (3.8%) of the 5-year-old cohort had developmental problems/delays. Two of them were previously diagnosed with a form of autism (pervasive developmental disorder-not otherwise specified). Two children had developmental problems based on our behavioral, cognitive, and/or motor assessments. The long-term effects on development and health in children born after TESE-ICSI procedures seem to be reassuring. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  8. Distortion of ultrashort pulses caused by aberrations

    NASA Astrophysics Data System (ADS)

    Horváth, Z. L.; Kovács, A. P.; Bor, Zs.

    The effect of the primary wave aberrations (spherical aberration, astigmatism and coma) on ultrashort pulses is studied by the Nijboer-Zernike theory. The results of the geometrical and the wave optical treatments are compared.

  9. Optimal Digital Controller Design for a Servo Motor Taking Account of Intersample Behavior

    NASA Astrophysics Data System (ADS)

    Akiyoshi, Tatsuro; Imai, Jun; Funabiki, Shigeyuki

    A continuous-time plant with discretized continuous-time controller do not yield stability if the sampling rate is lower than some certain level. Thus far, high functioning electronic control has made use of high cost hardwares which are needed to implement discretized continuous-time controllers, while low cost hardwares generally do not have high enough sampling rate. This technical note presents results comparing performance indices with and without intersample behavior, and some answer to the question how a low specification device can control a plant effectively. We consider a machine simulating wafer handling robots at semiconductor factories, which is an electromechanical system driven by a direct drive motor. We illustrate controller design for the robot with and without intersample behavior, and simulations and experimental results by using these controllers. Taking intersample behavior into account proves to be effective to make control performance better and enables it to choose relatively long sampling period. By controller design via performance index with intersample behavior, we can cope with situation where short enough sampling period may not be employed, and freedom of controller design might be widened especially on choice of sampling period.

  10. Pen-2 overexpression induces Aβ-42 production, memory defect, motor activity enhancement and feeding behavior dysfunction in NSE/Pen-2 transgenic mice.

    PubMed

    Nam, So Hee; Seo, Su Jin; Goo, Jun Seo; Kim, Jee Eun; Choi, Sun Il; Lee, Hae Ryun; Hwang, In Sik; Jee, Seung Wan; Lee, Su Hae; Bae, Chang Jun; Park, Jung Youn; Kim, Hye Sung; Shim, Sun Bo; Hwang, Dae Youn

    2011-12-01

    Pen-2 is a key regulator of the γ-secretase complex, which is involved in the production of the amyloid β (Aβ)-42 peptides, which ultimately lead to Alzheimer's disease (AD). While Pen-2 has been studied in vitro, Pen-2 function in vivo in the brains of transgenic (Tg) mice overexpressing human Pen-2 (hPen-2) protein has not been studied. This study aimed to determine whether Pen-2 overexpression could regulate the AD-like phenotypes in Tg mice. NSE/hPen-2 Tg mice were produced by the microinjection of the NSE/hPen-2 gene into the pronucleus of fertilized eggs. The expression of the hPen-2 gene under the control of the NSE promoter was successfully detected only in the brain and kidney tissue of NSE/hPen-2 Tg mice. Also, 12-month-old NSE/hPen-2 Tg mice displayed behavioral dysfunction in the water maze test, motor activity and feeding behavior dysfunction in food intake/water intake/motor activity monitoring system. In addition, tissue samples displayed dense staining with antibody to the Aβ-42 peptide. Furthermore, NSE/hPen-2 Tg mice exhibiting feeding behavior dysfunction were significantly more apt to display symptoms related to diabetes and obesity. These results suggest that Pen-2 overexpression in NSE/hPen-2 Tg mice may induce all the AD-like phenotypes, including behavioral deficits, motor activity and feeding behavior dysfunction, Aβ-42 peptide deposition and chronic disease induction.

  11. Vigorous, Aerobic Exercise versus General Motor Training Activities: Effects on Maladaptive and Stereotypic Behaviors of Adults with Both Autism and Mental Retardation.

    ERIC Educational Resources Information Center

    Elliott, Reed O., Jr.; And Others

    1994-01-01

    Six adults with both autism and moderate/profound mental retardation were assessed in a controlled environment for changes in frequency of maladaptive and stereotypic behaviors following nonexercise activities, general motor training activities, and aerobic exercise. Although antecedent aerobic exercise reduced undesirable behaviors, general motor…

  12. Aberration-free intraocular lenses - What does this really mean?

    PubMed

    Langenbucher, Achim; Schröder, Simon; Cayless, Alan; Eppig, Timo

    2017-09-01

    So-called aberration-free intraocular lenses (IOLs) are well established in modern cataract surgery. Usually, they are designed to perfectly refract a collimated light beam onto the focal point. We show how much aberration can be expected with such an IOL in a convergent light beam such as that found anterior to the human cornea. Additionally, the aberration in a collimated beam is estimated for an IOL that has no aberrations in the convergent beam. The convergent beam is modelled as the pencil of rays corresponding to the spherical wavefront resulting from a typical corneal power of 43m -1 . The IOLs are modelled as infinitely thin phase plates with 20m -1 optical power placed 5mm behind the cornea. Their aberrations are reported in terms of optical path length difference and longitudinal spherical aberration (LSA) of the marginal rays, as well as nominal spherical aberration (SA) calculated based on a Zernike representation of the wavefront-error at the corneal plane within a 6mm aperture. The IOL designed to have no aberrations in a collimated light beam has an optical path length difference of -1.8μm, and LSA of 0.15m -1 in the convergent beam of a typical eye. The corresponding nominal SA is 0.065μm. The IOL designed to have no aberrations in a convergent light beam has an optical path length difference of 1.8μm, and LSA of -0.15m -1 in the collimated beam. An IOL designed to have no aberrations in a collimated light beam will increase the SA of a patient's eye after implantation. Copyright © 2017. Published by Elsevier GmbH.

  13. Brain mechanisms controlling decision making and motor planning.

    PubMed

    Ramakrishnan, Arjun; Murthy, Aditya

    2013-01-01

    Accumulator models of decision making provide a unified framework to understand decision making and motor planning. In these models, the evolution of a decision is reflected in the accumulation of sensory information into a motor plan that reaches a threshold, leading to choice behavior. While these models provide an elegant framework to understand performance and reaction times, their ability to explain complex behaviors such as decision making and motor control of sequential movements in dynamic environments is unclear. To examine and probe the limits of online modification of decision making and motor planning, an oculomotor "redirect" task was used. Here, subjects were expected to change their eye movement plan when a new saccade target appeared. Based on task performance, saccade reaction time distributions, computational models of behavior, and intracortical microstimulation of monkey frontal eye fields, we show how accumulator models can be tested and extended to study dynamic aspects of decision making and motor control. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Motor Cortex Activity During Functional Motor Skills: An fNIRS Study.

    PubMed

    Nishiyori, Ryota; Bisconti, Silvia; Ulrich, Beverly

    2016-01-01

    Assessments of brain activity during motor task performance have been limited to fine motor movements due to technological constraints presented by traditional neuroimaging techniques, such as functional magnetic resonance imaging. Functional near-infrared spectroscopy (fNIRS) offers a promising method by which to overcome these constraints and investigate motor performance of functional motor tasks. The current study used fNIRS to quantify hemodynamic responses within the primary motor cortex in twelve healthy adults as they performed unimanual right, unimanual left, and bimanual reaching, and stepping in place. Results revealed that during both unimanual reaching tasks, the contralateral hemisphere showed significant activation in channels located approximately 3 cm medial to the C3 (for right-hand reach) and C4 (for left-hand reach) landmarks. Bimanual reaching and stepping showed activation in similar channels, which were located bilaterally across the primary motor cortex. The medial channels, surrounding Cz, showed significantly higher activations during stepping when compared to bimanual reaching. Our results extend the viability of fNIRS to study motor function and build a foundation for future investigation of motor development in infants during nascent functional behaviors and monitor how they may change with age or practice.

  15. Role of aberrant striatal dopamine D1 receptor/cAMP/protein kinase A/DARPP32 signaling in the paradoxical calming effect of amphetamine.

    PubMed

    Napolitano, Francesco; Bonito-Oliva, Alessandra; Federici, Mauro; Carta, Manolo; Errico, Francesco; Magara, Salvatore; Martella, Giuseppina; Nisticò, Robert; Centonze, Diego; Pisani, Antonio; Gu, Howard H; Mercuri, Nicola B; Usiello, Alessandro

    2010-08-18

    Attention deficit/hyperactivity disorder (ADHD) is characterized by inattention, impulsivity, and motor hyperactivity. Several lines of research support a crucial role for the dopamine transporter (DAT) gene in this psychiatric disease. Consistently, the most commonly prescribed medications in ADHD treatment are stimulant drugs, known to preferentially act on DAT. Recently, a knock-in mouse [DAT-cocaine insensitive (DAT-CI)] has been generated carrying a cocaine-insensitive DAT that is functional but with reduced dopamine uptake function. DAT-CI mutants display enhanced striatal extracellular dopamine levels and basal motor hyperactivity. Herein, we showed that DAT-CI animals present higher striatal dopamine turnover, altered basal phosphorylation state of dopamine and cAMP-regulated phosphoprotein 32 kDa (DARPP32) at Thr75 residue, but preserved D(2) receptor (D(2)R) function. However, although we demonstrated that striatal D(1) receptor (D(1)R) is physiologically responsive under basal conditions, its stimulus-induced activation strikingly resulted in paradoxical electrophysiological, behavioral, and biochemical responses. Indeed, in DAT-CI animals, (1) striatal LTP was completely disrupted, (2) R-(+)-6-chloro-7,8-dihydroxy-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrobromide (SKF 81297) treatment induced paradoxical motor calming effects, and (3) SKF 81297 administration failed to increase cAMP/protein kinase A (PKA)/DARPP32 signaling. Such biochemical alteration selectively affected dopamine D(1)Rs since haloperidol, by blocking the tonic inhibition of D(2)R, unmasked a normal activation of striatal adenosine A(2A) receptor-mediated cAMP/PKA/DARPP32 cascade in mutants. Most importantly, our studies highlighted that amphetamine, nomifensine, and bupropion, through increased striatal dopaminergic transmission, are able to revert motor hyperactivity of DAT-CI animals. Overall, our results suggest that the paradoxical motor calming effect induced by these

  16. Motor control in a Drosophila taste circuit

    PubMed Central

    Gordon, Michael D.; Scott, Kristin

    2009-01-01

    Tastes elicit innate behaviors critical for directing animals to ingest nutritious substances and reject toxic compounds, but the neural basis of these behaviors is not understood. Here, we use a neural silencing screen to identify neurons required for a simple Drosophila taste behavior, and characterize a neural population that controls a specific subprogram of this behavior. By silencing and activating subsets of the defined cell population, we identify the neurons involved in the taste behavior as a pair of motor neurons located in the subesophageal ganglion (SOG). The motor neurons are activated by sugar stimulation of gustatory neurons and inhibited by bitter compounds; however, experiments utilizing split-GFP detect no direct connections between the motor neurons and primary sensory neurons, indicating that further study will be necessary to elucidate the circuitry bridging these populations. Combined, these results provide a general strategy and a valuable starting point for future taste circuit analysis. PMID:19217375

  17. Automatic low-order aberrations compensator for a conduction-cooled end-pumped solid-state zigzag slab laser

    NASA Astrophysics Data System (ADS)

    Yu, Xin; Dong, Lizhi; Lai, Boheng; Yang, Ping; Wang, Shuai; Wang, Xun; Liu, Yong; Tang, Guomao; Xu, Bing

    2017-11-01

    In order to solve the problem of large low-order aberrations with solid-state zigzag slab lasers, an automatic compensator has been developed in this paper. In this compensator, three lenses are mounted on a motorized rail, whose positions can be obtained using ray tracing method based on the beam parameters detected by a wave-front sensor. The initial peak to valley (PV) values of the wave-front range up to several tens of microns. Both simulated and experimental results show that the PV values of the wave-front can be reduced to around 1 . 6 μm with the proposed automatic compensator.

  18. Vapb/Amyotrophic lateral sclerosis 8 knock-in mice display slowly progressive motor behavior defects accompanying ER stress and autophagic response.

    PubMed

    Larroquette, Frédérique; Seto, Lesley; Gaub, Perrine L; Kamal, Brishna; Wallis, Deeann; Larivière, Roxanne; Vallée, Joanne; Robitaille, Richard; Tsuda, Hiroshi

    2015-11-15

    Missense mutations (P56S) in Vapb are associated with autosomal dominant motor neuron diseases: amyotrophic lateral sclerosis and lower motor neuron disease. Although transgenic mice overexpressing the mutant vesicle-associated membrane protein-associated protein B (VAPB) protein with neuron-specific promoters have provided some insight into the toxic properties of the mutant proteins, their role in pathogenesis remains unclear. To identify pathological defects in animals expressing the P56S mutant VAPB protein at physiological levels in the appropriate tissues, we have generated Vapb knock-in mice replacing wild-type Vapb gene with P56S mutant Vapb gene and analyzed the resulting pathological phenotypes. Heterozygous P56S Vapb knock-in mice show mild age-dependent defects in motor behaviors as characteristic features of the disease. The homozygous P56S Vapb knock-in mice show more severe defects compared with heterozygous mice reflecting the dominant and dose-dependent effects of P56S mutation. Significantly, the knock-in mice demonstrate accumulation of P56S VAPB protein and ubiquitinated proteins in cytoplasmic inclusions, selectively in motor neurons. The mutant mice demonstrate induction of ER stress and autophagic response in motor neurons before obvious onset of behavioral defects, suggesting that these cellular biological defects might contribute to the initiation of the disease. The P56S Vapb knock-in mice could be a valuable tool to gain a better understanding of the mechanisms by which the disease arises. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Effect of aberrations in human eye on contrast sensitivity function

    NASA Astrophysics Data System (ADS)

    Quan, Wei; Wang, Feng-lin; Wang, Zhao-qi

    2011-06-01

    The quantitative analysis of the effect of aberrations in human eye on vision has important clinical value in the correction of aberrations. The wave-front aberrations of human eyes were measured with the Hartmann-Shack wave-front sensor and modulation transfer function (MTF) was computed from the wave-front aberrations. Contrast sensitivity function (CSF) was obtained from MTF and the retinal aerial image modulation (AIM). It is shown that the 2nd, 3rd, 4th, 5th, 6th Zernike aberrations deteriorate contrast sensitivity function. When the 2nd, 3rd, 4th, 5th, 6th Zernike aberrations are corrected high contrast sensitivity function can be obtained.

  20. Vitamin A depletion alters sensitivity of motor behavior to MK-801 in C57BL/6J mice.

    PubMed

    Zhang, Ming; Ji, Baohu; Zou, Hong; Shi, Junwei; Zhang, Zhao; Li, Xingwang; Zhu, Hui; Feng, Guoyin; Jin, Meilei; Yu, Lei; He, Lin; Wan, Chunling

    2010-01-22

    Vitamin A and its derivatives (retinoids) are crucial for the development, maintenance and morphogenesis of the central nervous system (CNS). Although motor impairment has been reported in postnatal vitamin A depletion rodents, the effect of vitamin A depletion on homeostasis maintaining capability in response to external interference is not clear. In the current study, we measured the effect of vitamin A depletion on motor ability and pain sensitivity under two different conditions: 1. prior to any injection and 2. after the injection of an N-methyl-D-aspartate (NMDA) receptor antagonist (MK-801). Vitamin A depletion mice showed decreased body weight, enhanced locomotor activity, increased rearing and less tail flick latency. Vitamin A depletion also induced hypersensitivity of stereotypy, ataxia, rearing, and tail flick latency to MK-801, but hyposensitivity of locomotion to MK-801. These findings suggest that vitamin A depletion affect broad basal behavior and disrupt homeostasis maintaining capability in response to glutamate perturbation. We provide a useful animal model for assessing the role of vitamin A depletion in regulating animal behavior, and for detecting how neurotransmitter pathways might be involved in vitamin A depletion related behavioral abnormalities.

  1. Sex-dependent alterations in motor and anxiety-like behavior of aged bacterial peptidoglycan sensing molecule 2 knockout mice.

    PubMed

    Arentsen, Tim; Khalid, Roksana; Qian, Yu; Diaz Heijtz, Rochellys

    2018-01-01

    Peptidoglycan recognition proteins (PGRPs) are key sensing-molecules of the innate immune system that specifically detect bacterial peptidoglycan (PGN) and its derivates. PGRPs have recently emerged as potential key regulators of normal brain development and behavior. To test the hypothesis that PGRPs play a role in motor control and anxiety-like behavior in later life, we used 15-month old male and female peptidoglycan recognition protein 2 (Pglyrp2) knockout (KO) mice. Pglyrp2 is an N-acetylmuramyl-l-alanine amidase that hydrolyzes PGN between the sugar backbone and the peptide chain (which is unique among the mammalian PGRPs). Using a battery of behavioral tests, we demonstrate that Pglyrp2 KO male mice display decreased levels of anxiety-like behavior compared with wild type (WT) males. In contrast, Pglyrp2 KO female mice show reduced rearing activity and increased anxiety-like behavior compared to WT females. In the accelerated rotarod test, however, Pglyrp2 KO female mice performed better compared to WT females (i.e., they had longer latency to fall off the rotarod). Further, Pglyrp2 KO male mice exhibited decreased expression levels of synaptophysin, gephyrin, and brain-derived neurotrophic factor in the frontal cortex, but not in the amygdala. Pglyrp2 KO female mice exhibited increased expression levels of spinophilin and alpha-synuclein in the frontal cortex, while exhibiting decreased expression levels of synaptophysin, gephyrin and spinophilin in the amygdala. Our findings suggest a novel role for Pglyrp2asa key regulator of motor and anxiety-like behavior in late life. Copyright © 2017. Published by Elsevier Inc.

  2. Effects of brain-derived neurotrophic factor on dopaminergic function and motor behavior during aging

    PubMed Central

    Boger, Heather A.; Mannangatti, Padmanabhan; Samuvel, Devadoss J.; Saylor, Alicia J.; Bender, Tara S.; McGinty, Jacqueline F.; Fortress, Ashley M.; Zaman, Vandana; Huang, Peng; Middaugh, Lawrence D.; Randall, Patrick K.; Jayanthi, Lankupalle D.; Rohrer, Baerbel; Helke, Kristi L.; Granholm, Ann-Charlotte; Ramamoorthy, Sammanda

    2010-01-01

    Brain-derived neurotrophic factor (BDNF) is critical in synaptic plasticity and in the survival and function of midbrain dopamine neurons. In the present study, we assessed the effects of a partial genetic deletion of BDNF on motor function and dopamine (DA) neurotransmitter measures by comparing (Bdnf+/−) with wildtype mice (WT) at different ages. Bdnf+/ and WT mice had similar body weights until 12 months of age; however, at 21 months, Bdnf+/− mice were significantly heavier than WT mice. Horizontal and vertical motor activity was reduced for Bdnf+/− compared to WT mice; but was not influenced by Age. Performance on an accelerating rotarod declined with age for both genotypes and was exacerbated for Bdnf+/− mice. Body weight did not correlate with any of the three behavioral measures studied. DA neurotransmitter markers indicated no genotypic difference in striatal tyrosine hydroxylase (TH), dopamine transporter (DAT), or vesicular monoamine transporter 2 (VMAT2) immunoreactivity at any age. However, DA transport via DAT (starting at 12 months) and VMAT2 (starting at 3 months) as well as KCl-stimulated DA release were reduced in Bdnf+/− mice and declined with age suggesting an increasingly important role for BDNF in the release and uptake of DA with the aging process. These findings suggest that a BDNF expression deficit becomes more critical to dopaminergic dynamics and related behavioral activities with increasing age. PMID:20860702

  3. Detecting independent and recurrent copy number aberrations using interval graphs.

    PubMed

    Wu, Hsin-Ta; Hajirasouliha, Iman; Raphael, Benjamin J

    2014-06-15

    Somatic copy number aberrations SCNAS: are frequent in cancer genomes, but many of these are random, passenger events. A common strategy to distinguish functional aberrations from passengers is to identify those aberrations that are recurrent across multiple samples. However, the extensive variability in the length and position of SCNA: s makes the problem of identifying recurrent aberrations notoriously difficult. We introduce a combinatorial approach to the problem of identifying independent and recurrent SCNA: s, focusing on the key challenging of separating the overlaps in aberrations across individuals into independent events. We derive independent and recurrent SCNA: s as maximal cliques in an interval graph constructed from overlaps between aberrations. We efficiently enumerate all such cliques, and derive a dynamic programming algorithm to find an optimal selection of non-overlapping cliques, resulting in a very fast algorithm, which we call RAIG (Recurrent Aberrations from Interval Graphs). We show that RAIG outperforms other methods on simulated data and also performs well on data from three cancer types from The Cancer Genome Atlas (TCGA). In contrast to existing approaches that employ various heuristics to select independent aberrations, RAIG optimizes a well-defined objective function. We show that this allows RAIG to identify rare aberrations that are likely functional, but are obscured by overlaps with larger passenger aberrations. http://compbio.cs.brown.edu/software. © The Author 2014. Published by Oxford University Press.

  4. Linear phase conjugation for atmospheric aberration compensation

    NASA Astrophysics Data System (ADS)

    Grasso, Robert J.; Stappaerts, Eddy A.

    1998-01-01

    Atmospheric induced aberrations can seriously degrade laser performance, greatly affecting the beam that finally reaches the target. Lasers propagated over any distance in the atmosphere suffer from a significant decrease in fluence at the target due to these aberrations. This is especially so for propagation over long distances. It is due primarily to fluctuations in the atmosphere over the propagation path, and from platform motion relative to the intended aimpoint. Also, delivery of high fluence to the target typically requires low beam divergence, thus, atmospheric turbulence, platform motion, or both results in a lack of fine aimpoint control to keep the beam directed at the target. To improve both the beam quality and amount of laser energy delivered to the target, Northrop Grumman has developed the Active Tracking System (ATS); a novel linear phase conjugation aberration compensation technique. Utilizing a silicon spatial light modulator (SLM) as a dynamic wavefront reversing element, ATS undoes aberrations induced by the atmosphere, platform motion or both. ATS continually tracks the target as well as compensates for atmospheric and platform motion induced aberrations. This results in a high fidelity, near-diffraction limited beam delivered to the target.

  5. Course of neuropsychiatric symptoms in residents with dementia in nursing homes over 2-year period.

    PubMed

    Wetzels, Roland B; Zuidema, Sytse U; de Jonghe, Jos F M; Verhey, Frans R J; Koopmans, Raymond T C M

    2010-12-01

    To determine the course of neuropsychiatric symptoms (NPSs) in nursing home residents with dementia and to determine their variability across diagnosis. Prospective cohort study over 2 years. Fourteen dementia special care units in nine nursing homes in The Netherlands. One hundred seventeen residents with dementia. NPSs were measured using the Neuropsychiatric Inventory-Nursing Home version (NPI-NH). The majority of residents had moderately severe to severe dementia. All but a few residents (97%) showed any NPS, and co-occurrence of NPSs was high. Agitation, irritability, and aberrant motor behavior were the most prevalent over the 2 years. Depression and anxiety as well as NPI total score decreased over time, whereas apathy tended to increase. Agitation and aberrant motor behavior were the most persistent symptoms. In asymptomatic residents, highest incidence rates were found for apathy, aggression/ agitation, irritability, and aberrant motor behavior. Anxiety and apathy were more prevalent in Alzheimer disease (AD) compared with vascular disease (VaD); vice versa, aggression and depression were more prevalent in VaD. Differences in change over time between AD and VaD were found for irritability and disinhibition. This is the first study examining the 2-year course of NPSs in a large group of nursing home residents with dementia. Virtually all residents demonstrated and/or developed NPSs. Although affective symptoms decreased, apathy tended to increase. Agitated behaviors were particularly persistent. Our data may contribute to improve mental healthcare for demented nursing home residents.

  6. Wave aberrations in rhesus monkeys with vision-induced ametropias

    PubMed Central

    Ramamirtham, Ramkumar; Kee, Chea-su; Hung, Li-Fang; Qiao-Grider, Ying; Huang, Juan; Roorda, Austin; Smith, Earl L.

    2007-01-01

    The purpose of this study was to investigate the relationship between refractive errors and high-order aberrations in infant rhesus monkeys. Specifically, we compared the monochromatic wave aberrations measured with a Shack-Hartman wavefront sensor between normal monkeys and monkeys with vision-induced refractive errors. Shortly after birth, both normal monkeys and treated monkeys reared with optically induced defocus or form deprivation showed a decrease in the magnitude of high-order aberrations with age. However, the decrease in aberrations was typically smaller in the treated animals. Thus, at the end of the lens-rearing period, higher than normal amounts of aberrations were observed in treated eyes, both hyperopic and myopic eyes and treated eyes that developed astigmatism, but not spherical ametropias. The total RMS wavefront error increased with the degree of spherical refractive error, but was not correlated with the degree of astigmatism. Both myopic and hyperopic treated eyes showed elevated amounts of coma and trefoil and the degree of trefoil increased with the degree of spherical ametropia. Myopic eyes also exhibited a much higher prevalence of positive spherical aberration than normal or treated hyperopic eyes. Following the onset of unrestricted vision, the amount of high-order aberrations decreased in the treated monkeys that also recovered from the experimentally induced refractive errors. Our results demonstrate that high-order aberrations are influenced by visual experience in young primates and that the increase in high-order aberrations in our treated monkeys appears to be an optical byproduct of the vision-induced alterations in ocular growth that underlie changes in refractive error. The results from our study suggest that the higher amounts of wave aberrations observed in ametropic humans are likely to be a consequence, rather than a cause, of abnormal refractive development. PMID:17825347

  7. Aberrations in stimulated emission depletion (STED) microscopy

    NASA Astrophysics Data System (ADS)

    Antonello, Jacopo; Burke, Daniel; Booth, Martin J.

    2017-12-01

    Like all methods of super-resolution microscopy, stimulated emission depletion (STED) microscopy can suffer from the effects of aberrations. The most important aspect of a STED microscope is that the depletion focus maintains a minimum, ideally zero, intensity point that is surrounded by a region of higher intensity. It follows that aberrations that cause a non-zero value of this minimum intensity are the most detrimental, as they inhibit fluorescence emission even at the centre of the depletion focus. We present analysis that elucidates the nature of these effects in terms of the different polarisation components at the focus for two-dimensional and three-dimensional STED resolution enhancement. It is found that only certain low-order aberration modes can affect the minimum intensity at the Gaussian focus. This has important consequences for the design of adaptive optics aberration correction systems.

  8. 3D resolved mapping of optical aberrations in thick tissues

    PubMed Central

    Zeng, Jun; Mahou, Pierre; Schanne-Klein, Marie-Claire; Beaurepaire, Emmanuel; Débarre, Delphine

    2012-01-01

    We demonstrate a simple method for mapping optical aberrations with 3D resolution within thick samples. The method relies on the local measurement of the variation in image quality with externally applied aberrations. We discuss the accuracy of the method as a function of the signal strength and of the aberration amplitude and we derive the achievable resolution for the resulting measurements. We then report on measured 3D aberration maps in human skin biopsies and mouse brain slices. From these data, we analyse the consequences of tissue structure and refractive index distribution on aberrations and imaging depth in normal and cleared tissue samples. The aberration maps allow the estimation of the typical aplanetism region size over which aberrations can be uniformly corrected. This method and data pave the way towards efficient correction strategies for tissue imaging applications. PMID:22876353

  9. Development and Validation of a Computational Model for Predicting the Behavior of Plumes from Large Solid Rocket Motors

    NASA Technical Reports Server (NTRS)

    Wells, Jason E.; Black, David L.; Taylor, Casey L.

    2013-01-01

    Exhaust plumes from large solid rocket motors fired at ATK's Promontory test site carry particulates to high altitudes and typically produce deposits that fall on regions downwind of the test area. As populations and communities near the test facility grow, ATK has become increasingly concerned about the impact of motor testing on those surrounding communities. To assess the potential impact of motor testing on the community and to identify feasible mitigation strategies, it is essential to have a tool capable of predicting plume behavior downrange of the test stand. A software package, called PlumeTracker, has been developed and validated at ATK for this purpose. The code is a point model that offers a time-dependent, physics-based description of plume transport and precipitation. The code can utilize either measured or forecasted weather data to generate plume predictions. Next-Generation Radar (NEXRAD) data and field observations from twenty-three historical motor test fires at Promontory were collected to test the predictive capability of PlumeTracker. Model predictions for plume trajectories and deposition fields were found to correlate well with the collected dataset.

  10. Aberrant regulation of DNA methylation in amyotrophic lateral sclerosis: a new target of disease mechanisms.

    PubMed

    Martin, Lee J; Wong, Margaret

    2013-10-01

    Amyotrophic lateral sclerosis (ALS) is the third most common adult-onset neurodegenerative disease. A diagnosis is fatal owing to degeneration of motor neurons in brain and spinal cord that control swallowing, breathing, and movement. ALS can be inherited, but most cases are not associated with a family history of the disease. The mechanisms causing motor neuron death in ALS are still unknown. Given the suspected complex interplay between multiple genes, the environment, metabolism, and lifestyle in the pathogenesis of ALS, we have hypothesized that the mechanisms of disease in ALS involve epigenetic contributions that can drive motor neuron degeneration. DNA methylation is an epigenetic mechanism for gene regulation engaged by DNA methyltransferase (Dnmt)-catalyzed methyl group transfer to carbon-5 in cytosine residues in gene regulatory promoter and nonpromoter regions. Recent genome-wide analyses have found differential gene methylation in human ALS. Neuropathologic assessments have revealed that motor neurons in human ALS show significant abnormalities in Dnmt1, Dnmt3a, and 5-methylcytosine. Similar changes are seen in mice with motor neuron degeneration, and Dnmt3a was found abundantly at synapses and in mitochondria. During apoptosis of cultured motor neuron-like cells, Dnmt1 and Dnmt3a protein levels increase, and 5-methylcytosine accumulates. Enforced expression of Dnmt3a, but not Dnmt1, induces degeneration of cultured neurons. Truncation mutation of the Dnmt3a catalytic domain and Dnmt3a RNAi blocks apoptosis of cultured neurons. Inhibition of Dnmt catalytic activity with small molecules RG108 and procainamide protects motor neurons from excessive DNA methylation and apoptosis in cell culture and in a mouse model of ALS. Thus, motor neurons can engage epigenetic mechanisms to cause their degeneration, involving Dnmts and increased DNA methylation. Aberrant DNA methylation in vulnerable cells is a new direction for discovering mechanisms of ALS

  11. Primary aberrations in focused radially polarized vortex beams

    NASA Astrophysics Data System (ADS)

    Biss, David P.; Brown, T. G.

    2004-02-01

    We study the effect of primary aberrations on the 3-D polarization of the electric field in a focused lowest order radially polarized beam. A full vector diffraction treatment of the focused beams is used. Attention is given to the effects of primary spherical, astigmatic, and comatic aberrations on the local polarization, Strehl ratio, and aberration induced degradation of the longitudinal field at focus

  12. Altered neuronal activities in the motor cortex with impaired motor performance in adult rats observed after infusion of cerebrospinal fluid from amyotrophic lateral sclerosis patients.

    PubMed

    Sankaranarayani, R; Nalini, A; Rao Laxmi, T; Raju, T R

    2010-01-05

    Although definite evidences are available to state that, neuronal activity is a prime determinant of animal behavior, the specific relationship between local field potentials of the motor cortex after intervention with CSF from human patients and animal behavior have remained opaque. The present study has investigated whether cerebrospinal fluid from sporadic amyotrophic lateral sclerosis (sALS) patients could disrupt neuronal activity of the motor cortex, which could be associated with disturbances in the motor performance of adult rats. CSF from ALS patients (ALS-CSF) was infused into the lateral ventricle of Wistar rats. After 24h, the impact of ALS-CSF on the local field potentials (LFPs) of the motor cortex and on the motor behavior of animals were examined. The results indicate that ALS-CSF produced a bivariate distribution on the relative power values of the LFPs of the motor cortex 24h following infusion. However, the behavioral results did not show bimodality, instead showed consistent decrease in motor performance: on rotarod and grip strength meter. The neuronal activity of the motor cortex negatively correlated with the duration of ALS symptoms at the time of lumbar puncture. Although the effect of ALS-CSF was more pronounced at 24h following infusion, the changes observed in LFPs and motor performance appeared to revert to baseline values at later time points of testing. In the current study, we have shown that, ALS-CSF has the potential to perturb neuronal activity of the rat motor cortex which was associated with poor performance on motor function tests.

  13. The Art of Optical Aberrations

    NASA Astrophysics Data System (ADS)

    Wylde, Clarissa Eileen Kenney

    Art and optics are inseparable. Though seemingly opposite disciplines, the combination of art and optics has significantly impacted both culture and science as they are now known. As history has run its course, in the sciences, arts, and their fruitful combinations, optical aberrations have proved to be a problematic hindrance to progress. In an effort to eradicate aberrations the simple beauty of these aberrational forms has been labeled as undesirable and discarded. Here, rather than approach aberrations as erroneous, these beautiful forms are elevated to be the photographic subject in a new body of work, On the Bright Side. Though many recording methods could be utilized, this work was composed on classic, medium-format, photographic film using white-light, Michelson interferometry. The resulting images are both a representation of the true light rays that interacted on the distorted mirror surfaces (data) and the artist's compositional eye for what parts of the interferogram are chosen and displayed. A detailed description of the captivating interdisciplinary procedure is documented and presented alongside the final artwork, CCD digital reference images, and deformable mirror contour maps. This alluring marriage between the arts and sciences opens up a heretofore minimally explored aspect of the inextricable art-optics connection. It additionally provides a fascinating new conversation on the importance of light and optics in photographic composition.

  14. Millisecond-Scale Motor Encoding in a Cortical Vocal Area

    NASA Astrophysics Data System (ADS)

    Nemenman, Ilya; Tang, Claire; Chehayeb, Diala; Srivastava, Kyle; Sober, Samuel

    2015-03-01

    Studies of motor control have almost universally examined firing rates to investigate how the brain shapes behavior. In principle, however, neurons could encode information through the precise temporal patterning of their spike trains as well as (or instead of) through their firing rates. Although the importance of spike timing has been demonstrated in sensory systems, it is largely unknown whether timing differences in motor areas could affect behavior. We tested the hypothesis that significant information about trial-by-trial variations in behavior is represented by spike timing in the songbird vocal motor system. We found that neurons in motor cortex convey information via spike timing far more often than via spike rate and that the amount of information conveyed at the millisecond timescale greatly exceeds the information available from spike counts. These results demonstrate that information can be represented by spike timing in motor circuits and suggest that timing variations evoke differences in behavior. This work was supported in part by the National Institutes of Health, National Science Foundation, and James S. McDonnell Foundation

  15. Visualization of oil behavior in a small 4-cycle engine with electrical motoring by neutron radiography

    NASA Astrophysics Data System (ADS)

    Nakamura, M.; Sugimoto, K.; Asano, H.; Murakawa, H.; Takenaka, N.; Mochiki, K.

    2009-06-01

    Neutron radiography is suitable for the visualization of liquid behavior in a metallic machine. Observation of oil behavior in a small 4-cycle engine on operating was carried out by using the neutron radiography facility at JRR-3 in JAEA. The engine was not fired but operated by an electrical motor. Movies were taken by a neutron image intensifier with a color CCD camera of 8-bit resolution, 30 frames/s and 640×480 pixels developed by Toshiba Corp. The engine was placed on a turn table and was rotated, so the movie could be taken from any angle. Numbers of revolution of the engine were changed from 260 to 1200 rpm. Visualized images of the mechanism and the oil behavior in the engine were obtained.

  16. Motor Skill Competence and Perceived Motor Competence: Which Best Predicts Physical Activity among Girls?

    PubMed

    Khodaverdi, Zeinab; Bahram, Abbas; Khalaji, Hassan; Kazemnejad, Anoshirvan

    2013-10-01

    The main purpose of this study was to determine which correlate, perceived motor competence or motor skill competence, best predicts girls' physical activity behavior. A sample of 352 girls (mean age=8.7, SD=0.3 yr) participated in this study. To assess motor skill competence and perceived motor competence, each child completed the Test of Gross Motor Development-2 and Physical Ability sub-scale of Marsh's Self-Description Questionnaire. Children's physical activity was assessed by the Physical Activity Questionnaire for Older Children. Multiple linear regression model was used to determine whether perceived motor competence or motor skill competence best predicts moderate-to-vigorous self-report physical activity. Multiple regression analysis indicated that motor skill competence and perceived motor competence predicted 21% variance in physical activity (R(2)=0.21, F=48.9, P=0.001), and motor skill competence (R(2)=0.15, ᵝ=0.33, P= 0.001) resulted in more variance than perceived motor competence (R(2)=0.06, ᵝ=0.25, P=0.001) in physical activity. Results revealed motor skill competence had more influence in comparison with perceived motor competence on physical activity level. We suggest interventional programs based on motor skill competence and perceived motor competence should be administered or implemented to promote physical activity in young girls.

  17. Idiosyncratic Functions: Severe Problem Behavior Maintained by Access to Ritualistic Behaviors

    ERIC Educational Resources Information Center

    Hausman, Nicole; Kahng, SungWoo; Farrell, Ellen; Mongeon, Camille

    2009-01-01

    The development of functional analysis technology has been an important tool in the assessment and treatment of aberrant behaviors among individuals with developmental disabilities. In some cases, the function of problem behavior may be idiosyncratic in nature, making modifications to functional analyses necessary. In the current study, a…

  18. Behavioral, Cognitive, and Motor Preparation Deficits in a Visual Cued Spatial Attention Task in Autism Spectrum Disorder

    PubMed Central

    Sokhadze, Estate M.; Tasman, Allan; Sokhadze, Guela E.; El-Baz, Ayman S.; Casanova, Manuel F.

    2015-01-01

    Abnormalities in motor skills have been regarded as part of the symptomatology characterizing autism spectrum disorder (ASD). It has been estimated that 80% of subjects with autism display “motor dyspraxia” or clumsiness that are not readily identified in a routine neurological examination. In this study we used behavioral measures, event-related potentials (ERP), and lateralized readiness potential (LRP) to study cognitive and motor preparation deficits contributing to the dyspraxia of autism. A modified Posner cueing task was used to analyze motor preparation abnormalities in children with autism and in typically developing children (N=30/per group). In this task, subjects engage in preparing motor response based on a visual cue, and then execute a motor movement based on the subsequent imperative stimulus. The experimental conditions, such as the validity of the cue and the spatial location of the target stimuli were manipulated to influence motor response selection, preparation, and execution. Reaction time and accuracy benefited from validly cued targets in both groups, while main effects of target spatial position were more obvious in the autism group. The main ERP findings were prolonged and more negative early frontal potentials in the ASD in incongruent trials in both types of spatial location. The LRP amplitude was larger in incongruent trials and had stronger effect in the children with ASD. These effects were better expressed at the earlier stages of LRP, specifically those related to response selection, and showed difficulties at the cognitive phase of stimulus processing rather that at the motor execution stage. The LRP measures at different stages reflect the chronology of cognitive aspects of movement preparation and are sensitive to manipulations of cue correctness, thus representing very useful biomarker in autism dyspraxia research. Future studies may use more advance and diverse manipulations of movement preparation demands in testing more

  19. Population dynamics of aberrant chromosome 1 in mice.

    PubMed

    Sabantsev, I; Spitsin, O; Agulnik, S; Ruvinsky, A

    1993-05-01

    Natural populations of two semispecies of house mouse, Mus musculus domesticus and M.m. musculus, were found to be polymorphic for an aberrant chromosome 1 bearing a large inserted block of homogeneously staining heterochromatin. Strong meiotic drive for the aberrant chromosome from M.m. musculus was previously observed in heterozygous female mice. There are at least three meiotic drive levels determined by different allelic variants of distorter. Homozygotes had low viability and females showed low fertility. Both homo- and heterozygous males had normal fertility and their segregation patterns did not deviate from normal. Computer simulations were performed of the dynamics of aberrant chromosome 1 in demes and populations. The data demonstrate that a spontaneous mutation (inversion) of an aberrant chromosome 1, once arisen, has a high probability of spreading in a population at high coefficients of meiotic drive and migration. In the long-term, the population attains a stationary state which is determined by the drive level and migration intensity. The state of stable genotypic equilibrium is independent of deme and population size, as well as of the initial concentration of the aberrant chromosome. As populations initially polymorphic for the distorters approach the stationary state, the stronger distorter is eliminated. The frequencies of the aberrant chromosome determined by computer analysis agree well with those obtained for the studied Asian M.m. musculus populations. The evolutionary pathways for the origin and fixation of the aberrant chromosome in natural populations are considered.

  20. Prenatal Exposure to Organohalogens, Including Brominated Flame Retardants, Influences Motor, Cognitive, and Behavioral Performance at School Age

    PubMed Central

    Roze, Elise; Meijer, Lisethe; Bakker, Attie; Van Braeckel, Koenraad N.J.A.; Sauer, Pieter J.J.; Bos, Arend F.

    2009-01-01

    Background Organohalogen compounds (OHCs) are known to have neurotoxic effects on the developing brain. Objective We investigated the influence of prenatal exposure to OHCs, including brominated flame retardants, on motor, cognitive, and behavioral outcome in healthy children of school age. Methods This study was part of the prospective Groningen infant COMPARE (Comparison of Exposure-Effect Pathways to Improve the Assessment of Human Health Risks of Complex Environmental Mixtures of Organohalogens) study. It included 62 children in whose mothers the following compounds had been determined in the 35th week of pregnancy: 2,2′-bis-(4 chlorophenyl)-1,1′-dichloroethene, pentachlorophenol (PCP), polychlorinated biphenyl congener 153 (PCB-153), 4-hydroxy-2,3,3′,4′,5-pentachlorobiphenyl (4OH-CB-107), 4OH-CB-146, 4OH-CB-187, 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47), BDE-99, BDE-100, BDE-153, BDE-154, and hexabromocyclododecane. Thyroid hormones were determined in umbilical cord blood. When the children were 5–6 years of age, we assessed their neuropsychological functioning: motor performance (coordination, fine motor skills), cognition (intelligence, visual perception, visuomotor integration, inhibitory control, verbal memory, and attention), and behavior. Results Brominated flame retardants correlated with worse fine manipulative abilities, worse attention, better coordination, better visual perception, and better behavior. Chlorinated OHCs correlated with less choreiform dyskinesia. Hydroxylated polychlorinated biphenyls correlated with worse fine manipulative abilities, better attention, and better visual perception. The wood protective agent (PCP) correlated with worse coordination, less sensory integrity, worse attention, and worse visuomotor integration. Conclusions Our results demonstrate for the first time that transplacental transfer of polybrominated flame retardants is associated with the development of children at school age. Because of the

  1. Prenatal exposure to organohalogens, including brominated flame retardants, influences motor, cognitive, and behavioral performance at school age.

    PubMed

    Roze, Elise; Meijer, Lisethe; Bakker, Attie; Van Braeckel, Koenraad N J A; Sauer, Pieter J J; Bos, Arend F

    2009-12-01

    Organohalogen compounds (OHCs) are known to have neurotoxic effects on the developing brain. We investigated the influence of prenatal exposure to OHCs, including brominated flame retardants, on motor, cognitive, and behavioral outcome in healthy children of school age. This study was part of the prospective Groningen infant COMPARE (Comparison of Exposure-Effect Pathways to Improve the Assessment of Human Health Risks of Complex Environmental Mixtures of Organohalogens) study. It included 62 children in whose mothers the following compounds had been determined in the 35th week of pregnancy: 2,2'-bis-(4 chlorophenyl)-1,1'-dichloroethene, pentachlorophenol (PCP), polychlorinated biphenyl congener 153 (PCB-153), 4-hydroxy-2,3,3',4',5-pentachlorobiphenyl (4OH-CB-107), 4OH-CB-146, 4OH-CB-187, 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), BDE-99, BDE-100, BDE-153, BDE-154, and hexabromocyclododecane. Thyroid hormones were determined in umbilical cord blood. When the children were 5-6 years of age, we assessed their neuropsychological functioning: motor performance (coordination, fine motor skills), cognition (intelligence, visual perception, visuomotor integration, inhibitory control, verbal memory, and attention), and behavior. Brominated flame retardants correlated with worse fine manipulative abilities, worse attention, better coordination, better visual perception, and better behavior. Chlorinated OHCs correlated with less choreiform dyskinesia. Hydroxylated polychlorinated biphenyls correlated with worse fine manipulative abilities, better attention, and better visual perception. The wood protective agent (PCP) correlated with worse coordination, less sensory integrity, worse attention, and worse visuomotor integration. Our results demonstrate for the first time that transplacental transfer of polybrominated flame retardants is associated with the development of children at school age. Because of the widespread use of these compounds, especially in the United States

  2. Factor validity and norms for the aberrant behavior checklist in a community sample of children with mental retardation.

    PubMed

    Marshburn, E C; Aman, M G

    1992-09-01

    The Aberrant Behavior Checklist (ABC) is a 58-item rating scale that was developed primarily to measure the effects of pharmacological intervention in individuals living in residential facilities. This study investigated the use of the ABC in a sample of community children with mental retardation. Teacher ratings on the ABC were collected on 666 students attending special classes. The data were factor analyzed and compared with other studies using the ABC. In addition, subscales were analyzed as a function of age, sex, and classroom placement, and preliminary norms were derived. A four-factor solution of the ABC was obtained. Congruence between the four derived factors and corresponding factors from the original ABC was high (congruence coefficients ranged between .87 and .96). Classroom placement and age had significant effects on subscale scores, whereas sex failed to affect ratings. The current results are sufficiently close to the original factor solution that the original scoring method can be used with community samples, although further studies are needed to look at this in more detail.

  3. Aberration design of zoom lens systems using thick lens modules.

    PubMed

    Zhang, Jinkai; Chen, Xiaobo; Xi, Juntong; Wu, Zhuoqi

    2014-12-20

    A systematic approach for the aberration design of a zoom lens system using a thick lens module is presented. Each component is treated as a thick lens module at the beginning of the design. A thick lens module refers to a thick lens component with a real lens structure, like lens materials, lens curvatures, lens thicknesses, and lens interval distances. All nine third-order aberrations of a thick lens component are considered during the design. The relationship of component aberrations in different zoom positions can be approximated from the aberration shift. After minimizing the aberrations of the zoom lens system, the nine third-order aberrations of every lens component can be determined. Then the thick lens structure of every lens component can be determined after optimization according to their first-order properties and third-order aberration targets. After a third optimization for minimum practical third-order aberrations of a zoom lens system, the aberration design using the thick lens module is complete, which provides a practical zoom lens system with thick lens structures. A double-sided telecentric zoom lens system is designed using the thick lens module in this paper, which shows that this method is practical for zoom lens design.

  4. Motor pathway convergence predicts syllable repertoire size in oscine birds

    PubMed Central

    Moore, Jordan M.; Székely, Tamás; Büki, József; DeVoogd, Timothy J.

    2011-01-01

    Behavioral specializations are frequently associated with expansions of the brain regions controlling them. This principle of proper mass spans sensory, motor, and cognitive abilities and has been observed in a wide variety of vertebrate species. Yet, it is unknown if this concept extrapolates to entire neural pathways or how selection on a behavioral capacity might otherwise shape circuit structure. We investigate these questions by comparing the songs and neuroanatomy of 49 species from 17 families of songbirds, which vary immensely in the number of unique song components they produce and possess a conserved neural network dedicated to this behavior. We find that syllable repertoire size is strongly related to the degree of song motor pathway convergence. Repertoire size is more accurately predicted by the number of neurons in higher motor areas relative to that in their downstream targets than by the overall number of neurons in the song motor pathway. Additionally, the convergence values along serial premotor and primary motor projections account for distinct portions of the behavioral variation. These findings suggest that selection on song has independently shaped different components of this hierarchical pathway, and they elucidate how changes in pathway structure could have underlain elaborations of this learned motor behavior. PMID:21918109

  5. Effects of altruism and burnout on driving behavior of bus drivers.

    PubMed

    Shi, Xia; Zhang, Liang

    2017-05-01

    Personality traits predict driving behaviors. However, the mechanism underlying this relationship has not been adequately investigated in professional drivers. The current study investigated the relationship between altruistic personality and aberrant driving behaviors, and the potential role of burnout. A total of 194 bus drivers completed questionnaires including measures of altruism, burnout and aberrant driving behaviors (aggressive violations, ordinary violations, errors, and lapses). The results showed that altruism was negatively correlated with burnout, and with all the four subcategories of aberrant driving behavior. Burnout fully mediated the relationship between altruism and aggressive violations, and partially mediated the relationship between altruism and lapses. These findings can be applied in the bus drivers' selection and interventions for burnout in order to improve the safety of public transport. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Activity in primary motor cortex during action observation covaries with subsequent behavioral changes in execution.

    PubMed

    Aridan, Nadav; Mukamel, Roy

    2016-11-01

    Observing someone else perform a movement facilitates motor planning, execution, and motor memory formation. Rate, an important feature in the execution of repeated movements, has been shown to vary following movement observation although the underlying neural mechanisms are unclear. In the current study, we examined how the rate of self-paced index finger pressing is implicitly modified following passive observation of a similar action performed at a different rate. Fifty subjects performed a finger pressing sequence with their right hand at their own pace before and after passive observation of either a 1-min video depicting the task performed at 3 Hz by someone else or a black screen. An additional set of 15 subjects performed the task in an MRI scanner. Across all 50 subjects, the spontaneous execution rate prior to video observation had a bimodal distribution with modes around 2 and 4 Hz. Following video observation, the slower subjects performed the task at an increased rate. In the 15 subjects who performed the task in the MRI scanner, we found positive correlation between fMRI signal in the left primary motor strip during passive video observation and subsequent behavioral changes in task performance rate. We conclude that observing someone else perform an action at a higher rate implicitly increases the spontaneous rate of execution, and that this implicit induction is mediated by activity in the contralateral primary motor cortex.

  7. Stereotyped Motor Behaviors Associated with Autism in High-Risk Infants: A Pilot Videotape Analysis of a Sibling Sample

    ERIC Educational Resources Information Center

    Loh, Alvin; Soman, Teesta; Brian, Jessica; Bryson, Susan E.; Roberts, Wendy; Szatmari, Peter; Smith, Isabel M.; Zwaigenbaum, Lonnie

    2007-01-01

    This study examined motor behaviors in a longitudinal cohort of infant siblings of children with autism. Stereotypic movements and postures occurring during standardized observational assessments at 12 and 18 months were coded from videotapes. Participants included eight infant siblings later diagnosed with autism spectrum disorder (ASD), a random…

  8. Relationships between Fine-Motor, Visual-Motor, and Visual Perception Scores and Handwriting Legibility and Speed

    ERIC Educational Resources Information Center

    Klein, Sheryl; Guiltner, Val; Sollereder, Patti; Cui, Ying

    2011-01-01

    Occupational therapists assess fine motor, visual motor, visual perception, and visual skill development, but knowledge of the relationships between scores on sensorimotor performance measures and handwriting legibility and speed is limited. Ninety-nine students in grades three to six with learning and/or behavior problems completed the Upper-Limb…

  9. Alterations in the brain adenosine metabolism cause behavioral and neurological impairment in ADA-deficient mice and patients

    PubMed Central

    Sauer, Aisha V.; Hernandez, Raisa Jofra; Fumagalli, Francesca; Bianchi, Veronica; Poliani, Pietro L.; Dallatomasina, Chiara; Riboni, Elisa; Politi, Letterio S.; Tabucchi, Antonella; Carlucci, Filippo; Casiraghi, Miriam; Carriglio, Nicola; Cominelli, Manuela; Forcellini, Carlo Alberto; Barzaghi, Federica; Ferrua, Francesca; Minicucci, Fabio; Medaglini, Stefania; Leocani, Letizia; la Marca, Giancarlo; Notarangelo, Lucia D.; Azzari, Chiara; Comi, Giancarlo; Baldoli, Cristina; Canale, Sabrina; Sessa, Maria; D’Adamo, Patrizia; Aiuti, Alessandro

    2017-01-01

    Adenosine Deaminase (ADA) deficiency is an autosomal recessive variant of severe combined immunodeficiency (SCID) caused by systemic accumulation of ADA substrates. Neurological and behavioral abnormalities observed in ADA-SCID patients surviving after stem cell transplantation or gene therapy represent an unresolved enigma in the field. We found significant neurological and cognitive alterations in untreated ADA-SCID patients as well as in two groups of patients after short- and long-term enzyme replacement therapy with PEG-ADA. These included motor dysfunction, EEG alterations, sensorineural hypoacusia, white matter and ventricular alterations in MRI as well as a low mental development index or IQ. Ada-deficient mice were significantly less active and showed anxiety-like behavior. Molecular and metabolic analyses showed that this phenotype coincides with metabolic alterations and aberrant adenosine receptor signaling. PEG-ADA treatment corrected metabolic adenosine-based alterations, but not cellular and signaling defects, indicating an intrinsic nature of the neurological and behavioral phenotype in ADA deficiency. PMID:28074903

  10. Alterations in the brain adenosine metabolism cause behavioral and neurological impairment in ADA-deficient mice and patients.

    PubMed

    Sauer, Aisha V; Hernandez, Raisa Jofra; Fumagalli, Francesca; Bianchi, Veronica; Poliani, Pietro L; Dallatomasina, Chiara; Riboni, Elisa; Politi, Letterio S; Tabucchi, Antonella; Carlucci, Filippo; Casiraghi, Miriam; Carriglio, Nicola; Cominelli, Manuela; Forcellini, Carlo Alberto; Barzaghi, Federica; Ferrua, Francesca; Minicucci, Fabio; Medaglini, Stefania; Leocani, Letizia; la Marca, Giancarlo; Notarangelo, Lucia D; Azzari, Chiara; Comi, Giancarlo; Baldoli, Cristina; Canale, Sabrina; Sessa, Maria; D'Adamo, Patrizia; Aiuti, Alessandro

    2017-01-11

    Adenosine Deaminase (ADA) deficiency is an autosomal recessive variant of severe combined immunodeficiency (SCID) caused by systemic accumulation of ADA substrates. Neurological and behavioral abnormalities observed in ADA-SCID patients surviving after stem cell transplantation or gene therapy represent an unresolved enigma in the field. We found significant neurological and cognitive alterations in untreated ADA-SCID patients as well as in two groups of patients after short- and long-term enzyme replacement therapy with PEG-ADA. These included motor dysfunction, EEG alterations, sensorineural hypoacusia, white matter and ventricular alterations in MRI as well as a low mental development index or IQ. Ada-deficient mice were significantly less active and showed anxiety-like behavior. Molecular and metabolic analyses showed that this phenotype coincides with metabolic alterations and aberrant adenosine receptor signaling. PEG-ADA treatment corrected metabolic adenosine-based alterations, but not cellular and signaling defects, indicating an intrinsic nature of the neurological and behavioral phenotype in ADA deficiency.

  11. Aberrant approach-avoidance conflict resolution following repeated cocaine pre-exposure.

    PubMed

    Nguyen, David; Schumacher, Anett; Erb, Suzanne; Ito, Rutsuko

    2015-10-01

    Addiction is characterized by persistence to seek drug reinforcement despite negative consequences. Drug-induced aberrations in approach and avoidance processing likely facilitate the sustenance of addiction pathology. Currently, the effects of repeated drug exposure on the resolution of conflicting approach and avoidance motivational signals have yet to be thoroughly investigated. The present study sought to investigate the effects of cocaine pre-exposure on conflict resolution using novel approach-avoidance paradigms. We used a novel mixed-valence conditioning paradigm to condition cocaine-pre-exposed rats to associate visuo-tactile cues with either the delivery of sucrose reward or shock punishment in the arms in which the cues were presented. Following training, exploration of an arm containing a superimposition of the cues was assessed as a measure of conflict resolution behavior. We also used a mixed-valence runway paradigm wherein cocaine-pre-exposed rats traversed an alleyway toward a goal compartment to receive a pairing of sucrose reward and shock punishment. Latency to enter the goal compartment across trials was taken as a measure of motivational conflict. Our results reveal that cocaine pre-exposure attenuated learning for the aversive cue association in our conditioning paradigm and enhanced preference for mixed-valence stimuli in both paradigms. Repeated cocaine pre-exposure allows appetitive approach motivations to gain greater influence over behavioral output in the context of motivational conflict, due to aberrant positive and negative incentive motivational processing.

  12. Sensitivity, Functional Analysis, and Behavior Genetics: A Response to Freeman et al.

    ERIC Educational Resources Information Center

    Reiss, Steven; Havercamp, Susan M.

    1999-01-01

    Sensitivity theory divides the causes of challenging behavior into three categories, aberrant contingencies, aberrant environments, and aberrant motivation. This paper replies to criticism that sensitivity theory is circular and unsupported by empirical evidence by reporting on studies that support the theory and rejecting the idea that…

  13. Assisting People with Multiple Disabilities and Minimal Motor Behavior to Control Environmental Stimulation through a Mouse Wheel

    ERIC Educational Resources Information Center

    Shih, Ching-Hsiang; Shih, Ching-Tien; Lin, Kun-Tsan; Chiang, Ming-Shan

    2009-01-01

    This study assessed whether two people with profound multiple disabilities and minimal motor behavior would be able to control environmental stimulation using thumb poke ability with a mouse wheel and a newly developed mouse driver (i.e., a new mouse driver replacing standard mouse driver, and turning a mouse into a precise thumb poke detector).…

  14. Novice drivers' individual trajectories of driver behavior over the first three years of driving.

    PubMed

    Roman, Gabriela D; Poulter, Damian; Barker, Edward; McKenna, Frank P; Rowe, Richard

    2015-09-01

    Identifying the changes in driving behavior that underlie the decrease in crash risk over the first few months of driving is key to efforts to reduce injury and fatality risk in novice drivers. This study represented a secondary data analysis of 1148 drivers who participated in the UK Cohort II study. The Driver Behavior Questionnaire was completed at 6 months and 1, 2 and 3 years after licensure. Linear latent growth models indicated significant increases across development in all four dimensions of aberrant driving behavior under scrutiny: aggressive violations, ordinary violations, errors and slips. Unconditional and conditional latent growth class analyses showed that the observed heterogeneity in individual trajectories was explained by the presence of multiple homogeneous groups of drivers, each exhibiting specific trajectories of aberrant driver behavior. Initial levels of aberrant driver behavior were important in identifying sub-groups of drivers. All classes showed positive slopes; there was no evidence of a group of drivers whose aberrant behavior decreased over time that might explain the decrease in crash involvement observed over this period. Male gender and younger age predicted membership of trajectories with higher levels of aberrant behavior. These findings highlight the importance of early intervention for improving road safety. We discuss the implications of our findings for understanding the behavioral underpinnings of the decrease in crash involvement observed in the early months of driving. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Aberration of a negative ion beam caused by space charge effect.

    PubMed

    Miyamoto, K; Wada, S; Hatayama, A

    2010-02-01

    Aberrations are inevitable when the charged particle beams are extracted, accelerated, transmitted, and focused with electrostatic and magnetic fields. In this study, we investigate the aberration of a negative ion accelerator for a neutral beam injector theoretically, especially the spherical aberration caused by the negative ion beam expansion due to the space charge effect. The negative ion current density profiles with the spherical aberration are compared with those without the spherical aberration. It is found that the negative ion current density profiles in a log scale are tailed due to the spherical aberration.

  16. Inter-cortical Modulation from Premotor to Motor Plasticity.

    PubMed

    Huang, Ying-Zu; Chen, Rou-Shayn; Fong, Po-Yu; Rothwell, John C; Chuang, Wen-Li; Weng, Yi-Hsin; Lin, Wey-Yil; Lu, Chin-Song

    2018-06-11

    Plasticity is involved in daily activities but abnormal plasticity may be deleterious. In this study, we found that motor plasticity could be modulated by suppressing the premotor cortex with the theta burst form of repetitive transcranial magnetic stimulation. Such changes in motor plasticity were associated with reduced learning of a simple motor task. We postulate that the premotor cortex adjusts the amount of motor plasticity to modulate motor learning through heterosynaptic metaplasticity. The present results provide an insight into how the brain physiologically coordinates two different areas to bring them into a functional network. This concept could be employed to intervene in diseases with abnormal plasticity. Primary motor cortex (M1) plasticity is known to be influenced by the excitability and prior activation history of M1 itself. However, little is known about how its plasticity is influenced by other areas of the brain. In the present study on humans of either sex who were known to respond to theta burst stimulation from previous studies, we found plasticity of M1 could be modulated by suppressing the premotor cortex with the theta burst form of repetitive transcranial magnetic stimulation. Motor plasticity was distorted and disappeared 30 min and 120 min respectively after premotor excitability was suppressed. Further evaluation revealed that such changes in motor plasticity were associated with impaired learning of a simple motor task. We postulate that the premotor cortex modulates the amount of plasticity within M1 through heterosynaptic metaplasticity, and that this may impact on learning of a simple motor task previously shown to be directly affected by M1 plasticity. The present results provide an insight into how the brain physiologically coordinates two different areas to bring them into a functional network. Furthermore, such concepts could be translated into therapeutic approaches for diseases with aberrant plasticity. This article is

  17. Evidence of motor-control difficulties in children with attention deficit hyperactivity disorder, explored through a hierarchical motor-systems perspective.

    PubMed

    Macoun, Sarah J; Kerns, Kimberly A

    2016-01-01

    Attention deficit hyperactivity disorder (ADHD) may reflect a disorder of neural systems that regulate motor control. The current study investigates motor dysfunction in children with ADHD using a hierarchical motor-systems perspective where frontal-striatal/"medial" brain systems are viewed as regulating parietal/"lateral" brain systems in a top down manner, to inhibit automatic environmentally driven responses in favor of goal-directed behavior. It was hypothesized that due to frontal-striatal hypoactivation, children with ADHD would have difficulty with higher order motor control tasks felt to be dependent on these systems, yet have preserved general motor function. A total of 63 children-ADHD and matched controls-completed experimental motor tasks that required maintenance of internal motor representations and the ability to inhibit visually driven responses. Children also completed a measure of motor inhibition, and a portion of the sample completed general motor function tasks. On motor tasks that required them to maintain internal motor representations and to inhibit automatic motor responses, children with ADHD had significantly greater difficulty than controls, yet on measures of general motor dexterity, their performance was comparable. Children with ADHD displayed significantly greater intraindividual (subject) variability than controls. Intraindividual variability (IIV) contributed to variations in performance across the motor tasks, but did not account for all of the variance on all tasks. These findings suggest that children with ADHD may be more controlled by external stimuli than by internally represented information, possibly due to dysfunction of the medial motor system. However, it is likely that children with ADHD also display general motor-execution problems (as evidenced by IIV findings), suggesting that atypicalities may extend to both medial and lateral motor systems. Findings are interpreted within the context of contemporary theories

  18. Aberrant regeneration of the third cranial nerve.

    PubMed

    Shrestha, U D; Adhikari, S

    2012-01-01

    Aberrant regeneration of the third cranial nerve is most commonly due to its damage by trauma. A ten-month old child presented with the history of a fall from a four-storey building. She developed traumatic third nerve palsy and eventually the clinical features of aberrant regeneration of the third cranial nerve. The adduction of the eye improved over time. She was advised for patching for the strabismic amblyopia as well. Traumatic third nerve palsy may result in aberrant regeneration of the third cranial nerve. In younger patients, motility of the eye in different gazes may improve over time. © NEPjOPH.

  19. Peripheral and central changes combine to induce motor behavioral deficits in a moderate repetition task

    PubMed Central

    Coq, Jacques-Olivier; Barr, Ann E; Strata, Fabrizio; Russier, Michael; Kietrys, David M; Merzenich, Michael M; Byl, Nancy N; Barbe, Mary F

    2009-01-01

    Repetitive motion disorders, such as carpal tunnel syndrome and focal hand dystonia, can be associated with tasks that require prolonged, repetitive behaviors. Previous studies using animal models of repetitive motion have correlated cortical neuroplastic changes or peripheral tissue inflammation with fine motor performance. However, the possibility that both peripheral and central mechanisms coexist with altered motor performance has not been studied. In this study, we investigated the relationship between motor behaviour changes associated with repetitive behaviors and both peripheral tissue inflammation and cortical neuroplasticity. A rat model of reaching and grasping involving moderate repetitive reaching with negligible force (MRNF) was used. Rats performed the MRNF task for 2 hrs/day, 3 days/wk for 8 weeks. Reach performance was monitored by measuring reach rate/success, daily exposure, reach movement reversals/patterns, reach/grasp phase times, grip strength and grooming function. With cumulative task exposure, reach performance, grip strength and agility declined while an inefficient food retrieval pattern increased. In S1 of MRNF rats, a dramatic disorganization of the topographic forepaw representation was observed, including the emergence of large receptive fields located on both the wrist/forearm and forepaw with alterations of neuronal properties. In M1, there was a drastic enlargement of the overall forepaw map area, and of the cortex devoted to digit, arm-digits and elbow-wrist responses. In addition, unusually low current amplitude evoked digit movements. IL-1β and TNF-α increased in forearm flexor muscles and tendons of MRNF animals. The increases in IL-1β and TNF-α negatively correlated with grip strength and amount of current needed to evoke forelimb movements. This study provides strong evidence that both peripheral inflammation and cortical neuroplasticity jointly contribute to the development of chronic repetitive motion disorders. PMID

  20. Mild cognitive impairment affects motor control and skill learning.

    PubMed

    Wu, Qiaofeng; Chan, John S Y; Yan, Jin H

    2016-02-01

    Mild cognitive impairment (MCI) is a transitional phase between normal cognitive aging and dementia. As the world population is aging rapidly, more MCI patients will be identified, posing significant problems to society. Normal aging is associated with cognitive and motor decline, and MCI brings additional impairments. Compared to healthy older adults, MCI patients show poorer motor control in a variety of tasks. Efficient motor control and skill learning are essential for occupational and leisure purposes; degradation of motor behaviors in MCI patients often adversely affects their health and quality of life. In this article, we first define MCI and describe its pathology and neural correlates. After this, we review cognitive changes and motor control and skill learning in normal aging. This section is followed by a discussion of MCI-related degradation of motor behaviors. Finally, we propose that multicomponent interventions targeting both cognitive and motor domains can improve MCI patients' motor functions. Future research directions are also raised.

  1. Visuomotor learning by passive motor experience

    PubMed Central

    Sakamoto, Takashi; Kondo, Toshiyuki

    2015-01-01

    Humans can adapt to unfamiliar dynamic and/or kinematic transformations through the active motor experience. Recent studies of neurorehabilitation using robots or brain-computer interface (BCI) technology suggest that passive motor experience would play a measurable role in motor recovery, however our knowledge of passive motor learning is limited. To clarify the effects of passive motor experience on human motor learning, we performed arm reaching experiments guided by a robotic manipulandum. The results showed that the passive motor experience had an anterograde transfer effect on the subsequent motor execution, whereas no retrograde interference was confirmed in the ABA paradigm experiment. This suggests that the passive experience of the error between visual and proprioceptive sensations leads to the limited but actual compensation of behavior, although it is fragile and cannot be consolidated as a persistent motor memory. PMID:26029091

  2. Motor Skill Competence and Perceived Motor Competence: Which Best Predicts Physical Activity among Girls?

    PubMed Central

    Khodaverdi, Zeinab; Bahram, Abbas; Khalaji, Hassan; Kazemnejad, Anoshirvan

    2013-01-01

    Abstract Background The main purpose of this study was to determine which correlate, perceived motor competence or motor skill competence, best predicts girls’ physical activity behavior. Methods A sample of 352 girls (mean age=8.7, SD=0.3 yr) participated in this study. To assess motor skill competence and perceived motor competence, each child completed the Test of Gross Motor Development-2 and Physical Ability sub-scale of Marsh’s Self-Description Questionnaire. Children’s physical activity was assessed by the Physical Activity Questionnaire for Older Children. Multiple linear regression model was used to determine whether perceived motor competence or motor skill competence best predicts moderate-to-vigorous self-report physical activity. Results Multiple regression analysis indicated that motor skill competence and perceived motor competence predicted 21% variance in physical activity (R2=0.21, F=48.9, P=0.001), and motor skill competence (R2=0.15, ᵝ=0.33, P= 0.001) resulted in more variance than perceived motor competence (R2=0.06, ᵝ=0.25, P=0.001) in physical activity. Conclusion Results revealed motor skill competence had more influence in comparison with perceived motor competence on physical activity level. We suggest interventional programs based on motor skill competence and perceived motor competence should be administered or implemented to promote physical activity in young girls. PMID:26060623

  3. Hydronephrosis by an Aberrant Renal Artery: A Case Report

    PubMed Central

    Park, Byoung Seok; Jeong, Taek Kyun; Ma, Seong Kwon; Kim, Soo Wan; Kim, Nam Ho; Choi, Ki Chul; Jeong, Yong Yeon

    2003-01-01

    Ureteropelvic junction obstruction is usually intrinsic and is most common in children. Aberrant renal arteries are present in about 30% of individuals. Aberrant renal arteries to the inferior pole cross anteriorly to the ureter and may cause hydronephrosis. To the best of our knowledge, although there are some papers about aberrant renal arteries producing ureteropelvic junction obstruction, there is no report of a case which is diagnosed by the new modalities, such as computed tomography angiogram (CTA) or magnetic resonance angiogram (MRA). We describe a 36-year-old woman with right hydronephrosis. Kidney ultrasonogram and excretory urogram revealed right hydronephrosis. CTA and MRA clearly displayed an aberrant renal artery and hydronephrosis. The patient underwent surgical exploration. For the evaluation of hydronephrosis by an aberrant renal artery, use of CTA and MRA is advocated. PMID:12760271

  4. Neural mechanisms of movement planning: motor cortex and beyond.

    PubMed

    Svoboda, Karel; Li, Nuo

    2018-04-01

    Neurons in motor cortex and connected brain regions fire in anticipation of specific movements, long before movement occurs. This neural activity reflects internal processes by which the brain plans and executes volitional movements. The study of motor planning offers an opportunity to understand how the structure and dynamics of neural circuits support persistent internal states and how these states influence behavior. Recent advances in large-scale neural recordings are beginning to decipher the relationship of the dynamics of populations of neurons during motor planning and movements. New behavioral tasks in rodents, together with quantified perturbations, link dynamics in specific nodes of neural circuits to behavior. These studies reveal a neural network distributed across multiple brain regions that collectively supports motor planning. We review recent advances and highlight areas where further work is needed to achieve a deeper understanding of the mechanisms underlying motor planning and related cognitive processes. Copyright © 2017. Published by Elsevier Ltd.

  5. Motor development in individuals with congenital adrenal hyperplasia: strength, targeting, and fine motor skill.

    PubMed

    Collaer, Marcia L; Brook, Charles G D; Conway, Gerard S; Hindmarsh, Peter C; Hines, Melissa

    2009-02-01

    This study investigated early androgen influence on the development of human motor and visuomotor characteristics. Participants, ages 12-45 years, were individuals with congenital adrenal hyperplasia (CAH), a disorder causing increased adrenal androgen production before birth (40 females, 29 males) and their unaffected relatives (29 females, 30 males). We investigated grip strength and visuomotor targeting tasks on which males generally outperform females, and fine motor pegboard tasks on which females generally outperform males. Physical characteristics (height and weight) were measured to explore whether body parameters could explain differences in motor skills. Females with CAH were stronger and showed better targeting than unaffected females and showed reduced fine visuomotor skill on one pegboard measure, with no difference on the other. Males with CAH were weaker than unaffected males in grip strength but did not differ on the targeting or pegboard measures. Correction for body size could not explain the findings for females, but suggests that the reduced strength of males with CAH may relate to their smaller stature. Further, the targeting advantage in females with CAH persisted following adjustment for their greater strength. Results in females support the hypothesis that androgen may masculinize, or promote, certain motor characteristics at which males excel, and contribute to defeminization of certain fine motor characteristics at which females excel. Thus, these data suggest that organizational effects of androgens on behavior during prenatal life may extend to motor characteristics and may contribute to general sex differences in motor-related behaviors; however, alternative explanations based on activational influences of androgen or altered experiential factors cannot be excluded without further study.

  6. Ocular higher-order aberrations in a school children population.

    PubMed

    Papamastorakis, George; Panagopoulou, Sophia; Tsilimbaris, Militadis K; Pallikaris, Ioannis G; Plainis, Sotiris

    2015-01-01

    The primary objective of the study was to explore the statistics of ocular higher-order aberrations in a population of primary and secondary school children. A sample of 557 children aged 10-15 years were selected from two primary and two secondary schools in Heraklion, Greece. Children were classified by age in three subgroups: group I (10.7±0.5 years), group II (12.4±0.5 years) and group III (14.5±0.5 years). Ocular aberrations were measured using a wavefront aberrometer (COAS, AMO Wavefront Sciences, USA) at mesopic light levels (illuminance at cornea was 4lux). Wavefront analysis was achieved for a 5mm pupil. Statistical analysis was carried out for the right eye only. The average coefficient of most high-order aberrations did not differ from zero with the exception of vertical (0.076μm) and horizontal (0.018μm) coma, oblique trefoil (-0.055μm) and spherical aberration (0.018μm). The most prominent change between the three groups was observed for the spherical aberration, which increased from 0.007μm (SE 0.005) in group I to 0.011μm (SE 0.004) in group II and 0.030μm (SE 0.004) in group III. Significant differences were also found for the oblique astigmatism and the third-order coma aberrations. Differences in the low levels of ocular spherical aberration in young children possibly reflect differences in lenticular spherical aberration and relate to the gradient refractive index of the lens. The evaluation of spherical aberration at certain stages of eye growth may help to better understand the underlying mechanisms of myopia development. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  7. Ocular higher-order aberrations in a school children population

    PubMed Central

    Papamastorakis, George; Panagopoulou, Sophia; Tsilimbaris, Militadis K.; Pallikaris, Ioannis G.; Plainis, Sotiris

    2014-01-01

    Purpose The primary objective of the study was to explore the statistics of ocular higher-order aberrations in a population of primary and secondary school children. Methods A sample of 557 children aged 10–15 years were selected from two primary and two secondary schools in Heraklion, Greece. Children were classified by age in three subgroups: group I (10.7 ± 0.5 years), group II (12.4 ± 0.5 years) and group III (14.5 ± 0.5 years). Ocular aberrations were measured using a wavefront aberrometer (COAS, AMO Wavefront Sciences, USA) at mesopic light levels (illuminance at cornea was 4 lux). Wavefront analysis was achieved for a 5 mm pupil. Statistical analysis was carried out for the right eye only. Results The average coefficient of most high-order aberrations did not differ from zero with the exception of vertical (0.076 μm) and horizontal (0.018 μm) coma, oblique trefoil (−0.055 μm) and spherical aberration (0.018 μm). The most prominent change between the three groups was observed for the spherical aberration, which increased from 0.007 μm (SE 0.005) in group I to 0.011 μm (SE 0.004) in group II and 0.030 μm (SE 0.004) in group III. Significant differences were also found for the oblique astigmatism and the third-order coma aberrations. Conclusions Differences in the low levels of ocular spherical aberration in young children possibly reflect differences in lenticular spherical aberration and relate to the gradient refractive index of the lens. The evaluation of spherical aberration at certain stages of eye growth may help to better understand the underlying mechanisms of myopia development. PMID:25288226

  8. GABAergic influences on ORX receptor-dependent abnormal motor behaviors and neurodegenerative events in fish

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Facciolo, Rosa Maria, E-mail: rm.facciolo@unical.i; Crudo, Michele; Giusi, Giuseppina

    2010-02-15

    At date the major neuroreceptors i.e. gamma-aminobutyric acid{sub A} (GABA{sub A}R) and orexin (ORXR) systems are beginning to be linked to homeostasis, neuroendocrine and emotional states. In this study, intraperitoneal treatment of the marine teleost Thalassoma pavo with the highly selective GABA{sub A}R agonist (muscimol, MUS; 0,1 mug/g body weight) and/or its antagonist bicuculline (BIC; 1 mug/g body weight) have corroborated a GABA{sub A}ergic role on motor behaviors. In particular, MUS induced moderate (p < 0.05) and great (p < 0.01) increases of swimming towards food sources and resting states after 24 (1 dose) and 96 (4 doses) h treatmentmore » sessions, respectively, when compared to controls. Conversely, BIC caused a very strong (p < 0.001) reduction of the former behavior and in some cases convulsive swimming. From the correlation of BIC-dependent behavioral changes to neuronal morphological and ORXR transcriptional variations, it appeared that the disinhibitory action of GABA{sub A}R was very likely responsible for very strong and strong ORXR mRNA reductions in cerebellum valvula and torus longitudinalis, respectively. Moreover these effects were linked to evident ultra-structural changes such as shrunken cell membranes and loss of cytoplasmic architecture. In contrast, MUS supplied a very low, if any, argyrophilic reaction in hypothalamic and mesencephalic regions plus a scarce level of ultra-structural damages. Interestingly, combined administrations of MUS + BIC were not related to consistent damages, aside mild neuronal alterations in motor-related areas such as optic tectum. Overall it is tempting to suggest, for the first time, a neuroprotective role of GABA{sub A}R inhibitory actions against the overexcitatory ORXR-dependent neurodegeneration and consequently abnormal swimming events in fish.« less

  9. Generalized Alvarez lens for correction of laser aberrations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    LaFortune, K N

    2004-12-02

    The Alvarez lens (US Patent No. 3,305,294 [1]) is a compact aberration corrector. The original design emphasized in the patent consists of a pair of adjacent optical elements that provide a variable focus. A lens system with a variable effective focal length is nothing new. Such systems are widely used in cameras, for example. It is the compactness and simplicity of operation that is the key advantage of the Alvarez lens. All of the complexity is folded into the design and fabrication of the optical elements. As mentioned in the Alvarez patent [1] and elaborated upon in Palusinski et al.more » [2], if one is willing to fold even more complexity into the optical elements, it is possible to correct higher-order aberrations as well. There is no theoretical limit to the number or degree of wavefront distortions that can be corrected. The only limitation is that there must be a fixed relative magnitude of the aberrations. Independent correction of each component of the higher-order aberrations can not be performed without additional elements and degrees of freedom [3]. Under some circumstances, coupling may be observed between different aberrations. This can be mitigated with the appropriate choice of design parameters. New methods are available today that increase the practicality of making higher-order aberration correctors [4,5,6].« less

  10. Post-impact behavior of composite solid rocket motor cases

    NASA Technical Reports Server (NTRS)

    Highsmith, Alton L.

    1992-01-01

    In recent years, composite materials have seen increasing use in advanced structural applications because of the significant weight savings they offer when compared to more traditional engineering materials. The higher cost of composites must be offset by the increased performance that results from reduced structural weight if these new materials are to be used effectively. At present, there is considerable interest in fabricating solid rocket motor cases out of composite materials, and capitalizing on the reduced structural weight to increase rocket performance. However, one of the difficulties that arises when composite materials are used is that composites can develop significant amounts of internal damage during low velocity impacts. Such low velocity impacts may be encountered in routine handling of a structural component like a rocket motor case. The ability to assess the reduction in structural integrity of composite motor cases that experience accidental impacts is essential if composite rocket motor cases are to be certified for manned flight. The study described herein was an initial investigation of damage development and reduction of tensile strength in an idealized composite subjected to low velocity impacts.

  11. Determination of the motor unit behavior of lumbar erector spinae muscles through surface EMG decomposition technology in healthy female subjects.

    PubMed

    Silva, Mariana Felipe; Dias, Josilainne Marcelino; Pereira, Ligia Maxwell; Mazuquin, Bruno Fles; Lindley, Steven; Richards, Jim; Cardoso, Jefferson Rosa

    2017-01-01

    The aims of this study were to determine the motor unit behavior of the erector spinae muscles and to assess whether differences exist between the dominant/nondominant sides of the back muscles. Nine healthy women, aged 21.7 years (SD = 0.7), performed a back extension test. Surface electromyographic decomposition data were collected from both sides of the erector spinae and decomposed into individual motor unit action potential trains. The mean firing rate for each motor unit was calculated, and a regression analysis was performed against the corresponding recruitment thresholds. The mean firing rate ranged from 15.9 to 23.9 pps and 15.8 to 20.6 pps on the dominant and nondominant sides, respectively. However, the early motor unit potentials of the nondominant lumbar erector spinae muscles were recruited at a lower firing rate. This technique may further our understanding of individuals with back pain and other underlying neuromuscular diseases. Muscle Nerve 55: 28-34, 2017. © 2016 Wiley Periodicals, Inc.

  12. Statistical estimation of ultrasonic propagation path parameters for aberration correction.

    PubMed

    Waag, Robert C; Astheimer, Jeffrey P

    2005-05-01

    Parameters in a linear filter model for ultrasonic propagation are found using statistical estimation. The model uses an inhomogeneous-medium Green's function that is decomposed into a homogeneous-transmission term and a path-dependent aberration term. Power and cross-power spectra of random-medium scattering are estimated over the frequency band of the transmit-receive system by using closely situated scattering volumes. The frequency-domain magnitude of the aberration is obtained from a normalization of the power spectrum. The corresponding phase is reconstructed from cross-power spectra of subaperture signals at adjacent receive positions by a recursion. The subapertures constrain the receive sensitivity pattern to eliminate measurement system phase contributions. The recursion uses a Laplacian-based algorithm to obtain phase from phase differences. Pulse-echo waveforms were acquired from a point reflector and a tissue-like scattering phantom through a tissue-mimicking aberration path from neighboring volumes having essentially the same aberration path. Propagation path aberration parameters calculated from the measurements of random scattering through the aberration phantom agree with corresponding parameters calculated for the same aberrator and array position by using echoes from the point reflector. The results indicate the approach describes, in addition to time shifts, waveform amplitude and shape changes produced by propagation through distributed aberration under realistic conditions.

  13. Wild-type and mutant SOD1 share an aberrant conformation and a common pathogenic pathway in ALS

    PubMed Central

    Bosco, Daryl A.; Morfini, Gerardo; Karabacak, N. Murat; Song, Yuyu; Gros-Louis, Francois; Pasinelli, Piera; Goolsby, Holly; Fontaine, Benjamin A.; Lemay, Nathan; McKenna-Yasek, Diane; Frosch, Matthew P.; Agar, Jeffery N.; Julien, Jean-Pierre; Brady, Scott T.; Brown, Robert H.

    2010-01-01

    Many mutations confer upon copper/zinc superoxide dismutase-1 (SOD1) one or more toxic function(s) that impair motor neuron viability and cause familial amyotrophic lateral sclerosis (FALS). Using a conformation-specific antibody that detects misfolded SOD1 (C4F6), we demonstrate that oxidized WT-SOD1 and mutant-SOD1 share a conformational epitope that is not present in normal WT-SOD1. In a subset of human sporadic ALS (SALS) cases, motor neurons in the lumbosacral spinal cord displayed striking C4F6 immunoreactivity, denoting the presence of aberrant WT-SOD1 species. Recombinant, oxidized WT-SOD1 and WT-SOD1 immunopurified from SALS tissues inhibited kinesin-based fast axonal transport in a manner similar to FALS-linked mutant SOD1. Studies here suggest that WT-SOD1 can be pathogenic in SALS and identifies an SOD1-dependent pathogenic mechanism common to FALS and SALS. PMID:20953194

  14. Composite Material Testing Data Reduction to Adjust for the Systematic 6-DOF Testing Machine Aberrations

    Treesearch

    Athanasios lliopoulos; John G. Michopoulos; John G. C. Hermanson

    2012-01-01

    This paper describes a data reduction methodology for eliminating the systematic aberrations introduced by the unwanted behavior of a multiaxial testing machine, into the massive amounts of experimental data collected from testing of composite material coupons. The machine in reference is a custom made 6-DoF system called NRL66.3 and developed at the NAval...

  15. Randomized, single-blind, controlled trial of a specialist behavior therapy team for challenging behavior in adults with intellectual disabilities.

    PubMed

    Hassiotis, Angela; Robotham, Dan; Canagasabey, Anton; Romeo, Renee; Langridge, Diane; Blizard, Robert; Murad, Shahed; King, Michael

    2009-11-01

    Community-based specialist behavior therapy teams may be helpful in managing challenging behavior, but evidence of their effectiveness is limited. This study was designed to examine the effectiveness and costs associated with treatment by a specialist behavior therapy team. This was a parallel-group, randomized, single-blind controlled trial carried out in an intellectual disabilities service in England. Participants were 63 male and female service users with mild to severe intellectual disability who presented with challenging behavior. The interventions were standard treatment plus applied behavioral analysis (N=32) and standard treatment only (N=31). The primary outcome measure was challenging behavior, as measured by total and subscale scores on the Aberrant Behavior Checklist 3 and 6 months after randomization. Secondary outcome measures were psychiatric comorbidity assessed at 3 and 6 months using the Psychiatric Assessment Schedule for Adults With a Developmental Disability Checklist (PAS-ADD) and total costs recorded at 6 months. Multilevel modeling was used to compare square root transformations of Aberrant Behavior Checklist scores. Significant differences were found in the transformed total scores on the Aberrant Behavior Checklist (difference=-0.89, 95% CI=-1.74 to -0.04) and transformed lethargy and hyperactivity subscale scores (common intervention effect=-0.56, 95% CI=-0.97 to -0.15). Standard care participants fared worse on the PAS-ADD comorbid organic disorder subscale. There was a clear trend for lower overall costs of the intervention. Use of a specialist behavior therapy team in addition to standard treatment appears to be more effective in improving challenging behavior and may have financial advantages over standard treatment.

  16. Direct modulation of aberrant brain network connectivity through real-time NeuroFeedback.

    PubMed

    Ramot, Michal; Kimmich, Sara; Gonzalez-Castillo, Javier; Roopchansingh, Vinai; Popal, Haroon; White, Emily; Gotts, Stephen J; Martin, Alex

    2017-09-16

    The existence of abnormal connectivity patterns between resting state networks in neuropsychiatric disorders, including Autism Spectrum Disorder (ASD), has been well established. Traditional treatment methods in ASD are limited, and do not address the aberrant network structure. Using real-time fMRI neurofeedback, we directly trained three brain nodes in participants with ASD, in which the aberrant connectivity has been shown to correlate with symptom severity. Desired network connectivity patterns were reinforced in real-time, without participants' awareness of the training taking place. This training regimen produced large, significant long-term changes in correlations at the network level, and whole brain analysis revealed that the greatest changes were focused on the areas being trained. These changes were not found in the control group. Moreover, changes in ASD resting state connectivity following the training were correlated to changes in behavior, suggesting that neurofeedback can be used to directly alter complex, clinically relevant network connectivity patterns.

  17. Direct modulation of aberrant brain network connectivity through real-time NeuroFeedback

    PubMed Central

    Kimmich, Sara; Gonzalez-Castillo, Javier; Roopchansingh, Vinai; Popal, Haroon; White, Emily; Gotts, Stephen J; Martin, Alex

    2017-01-01

    The existence of abnormal connectivity patterns between resting state networks in neuropsychiatric disorders, including Autism Spectrum Disorder (ASD), has been well established. Traditional treatment methods in ASD are limited, and do not address the aberrant network structure. Using real-time fMRI neurofeedback, we directly trained three brain nodes in participants with ASD, in which the aberrant connectivity has been shown to correlate with symptom severity. Desired network connectivity patterns were reinforced in real-time, without participants’ awareness of the training taking place. This training regimen produced large, significant long-term changes in correlations at the network level, and whole brain analysis revealed that the greatest changes were focused on the areas being trained. These changes were not found in the control group. Moreover, changes in ASD resting state connectivity following the training were correlated to changes in behavior, suggesting that neurofeedback can be used to directly alter complex, clinically relevant network connectivity patterns. PMID:28917059

  18. Anticipatory activity in primary motor cortex codes memorized movement sequences.

    PubMed

    Lu, Xiaofeng; Ashe, James

    2005-03-24

    Movement sequences, defined both by the component movements and by the serial order in which they are produced, are fundamental building blocks of motor behavior. The serial order of sequence production is strongly encoded in medial motor areas. It is not known to what extent sequences are further elaborated or encoded in primary motor cortex. Here, we describe cells in the primary motor cortex of the monkey that show anticipatory activity exclusively related to a specific memorized sequence of upcoming movements. In addition, the injection of muscimol, a GABA agonist, into motor cortex resulted in an increase in the error rate during sequence production, without concomitant effects on nonsequenced motor performance. Our results challenge the role of medial motor areas in the control of well-practiced movement sequences and suggest that motor cortex contains a complete apparatus for the planning and production of this complex behavior.

  19. Influence of Misalignment on High-Order Aberration Correction for Normal Human Eyes

    NASA Astrophysics Data System (ADS)

    Zhao, Hao-Xin; Xu, Bing; Xue, Li-Xia; Dai, Yun; Liu, Qian; Rao, Xue-Jun

    2008-04-01

    Although a compensation device can correct aberrations of human eyes, the effect will be degraded by its misalignment, especially for high-order aberration correction. We calculate the positioning tolerance of correction device for high-order aberrations, and within what degree the correcting effect is better than low-order aberration (defocus and astigmatism) correction. With fixed certain misalignment within the positioning tolerance, we calculate the residual wavefront rms aberration of the first-6 to first-35 terms along with the 3rd-5th terms of aberrations corrected, and the combined first-13 terms of aberrations are also studied under the same quantity of misalignment. However, the correction effect of high-order aberrations does not meliorate along with the increase of the high-order terms under some misalignment, moreover, some simple combined terms correction can achieve similar result as complex combinations. These results suggest that it is unnecessary to correct too much the terms of high-order aberrations which are difficult to accomplish in practice, and gives confidence to correct high-order aberrations out of the laboratory.

  20. Orthonormal aberration polynomials for anamorphic optical imaging systems with rectangular pupils.

    PubMed

    Mahajan, Virendra N

    2010-12-20

    The classical aberrations of an anamorphic optical imaging system, representing the terms of a power-series expansion of its aberration function, are separable in the Cartesian coordinates of a point on its pupil. We discuss the balancing of a classical aberration of a certain order with one or more such aberrations of lower order to minimize its variance across a rectangular pupil of such a system. We show that the balanced aberrations are the products of two Legendre polynomials, one for each of the two Cartesian coordinates of the pupil point. The compound Legendre polynomials are orthogonal across a rectangular pupil and, like the classical aberrations, are inherently separable in the Cartesian coordinates of the pupil point. They are different from the balanced aberrations and the corresponding orthogonal polynomials for a system with rotational symmetry but a rectangular pupil.

  1. Assisting People with Multiple Disabilities and Minimal Motor Behavior to Improve Computer Pointing Efficiency through a Mouse Wheel

    ERIC Educational Resources Information Center

    Shih, Ching-Hsiang; Chang, Man-Ling; Shih, Ching-Tien

    2009-01-01

    This study evaluated whether two people with multiple disabilities and minimal motor behavior would be able to improve their pointing performance using finger poke ability with a mouse wheel through a Dynamic Pointing Assistive Program (DPAP) and a newly developed mouse driver (i.e., a new mouse driver replaces standard mouse driver, changes a…

  2. Children with Multiple Disabilities and Minimal Motor Behavior Using Chin Movements to Operate Microswitches to Obtain Environmental Stimulation

    ERIC Educational Resources Information Center

    Lancioni, Giulio E.; O'Reilly, Mark F.; Singh, Nirbhay N.; Sigafoos, Jeff; Tota, Alessia; Antonucci, Massimo; Oliva, Doretta

    2006-01-01

    In these two studies, two children with multiple disabilities and minimal motor behavior were assessed to see if they could use chin movements to operate microswitches to obtain environmental stimulation. In Study I, we applied an adapted version of a recently introduced electronic microswitch [Lancioni, G. E., O'Reilly, M. F., Singh, N. N.,…

  3. Multiple Sensory-Motor Pathways Lead to Coordinated Visual Attention

    PubMed Central

    Yu, Chen; Smith, Linda B.

    2016-01-01

    Joint attention has been extensively studied in the developmental literature because of overwhelming evidence that the ability to socially coordinate visual attention to an object is essential to healthy developmental outcomes, including language learning. The goal of the present study is to understand the complex system of sensory-motor behaviors that may underlie the establishment of joint attention between parents and toddlers. In an experimental task, parents and toddlers played together with multiple toys. We objectively measured joint attention – and the sensory-motor behaviors that underlie it – using a dual head-mounted eye-tracking system and frame-by-frame coding of manual actions. By tracking the momentary visual fixations and hand actions of each participant, we precisely determined just how often they fixated on the same object at the same time, the visual behaviors that preceded joint attention, and manual behaviors that preceded and co-occurred with joint attention. We found that multiple sequential sensory-motor patterns lead to joint attention. In addition, there are developmental changes in this multi-pathway system evidenced as variations in strength among multiple routes. We propose that coordinated visual attention between parents and toddlers is primarily a sensory-motor behavior. Skill in achieving coordinated visual attention in social settings – like skills in other sensory-motor domains – emerges from multiple pathways to the same functional end. PMID:27016038

  4. Multiple Sensory-Motor Pathways Lead to Coordinated Visual Attention.

    PubMed

    Yu, Chen; Smith, Linda B

    2017-02-01

    Joint attention has been extensively studied in the developmental literature because of overwhelming evidence that the ability to socially coordinate visual attention to an object is essential to healthy developmental outcomes, including language learning. The goal of this study was to understand the complex system of sensory-motor behaviors that may underlie the establishment of joint attention between parents and toddlers. In an experimental task, parents and toddlers played together with multiple toys. We objectively measured joint attention-and the sensory-motor behaviors that underlie it-using a dual head-mounted eye-tracking system and frame-by-frame coding of manual actions. By tracking the momentary visual fixations and hand actions of each participant, we precisely determined just how often they fixated on the same object at the same time, the visual behaviors that preceded joint attention and manual behaviors that preceded and co-occurred with joint attention. We found that multiple sequential sensory-motor patterns lead to joint attention. In addition, there are developmental changes in this multi-pathway system evidenced as variations in strength among multiple routes. We propose that coordinated visual attention between parents and toddlers is primarily a sensory-motor behavior. Skill in achieving coordinated visual attention in social settings-like skills in other sensory-motor domains-emerges from multiple pathways to the same functional end. Copyright © 2016 Cognitive Science Society, Inc.

  5. Sexual motivation is reflected by stimulus-dependent motor cortex excitability.

    PubMed

    Schecklmann, Martin; Engelhardt, Kristina; Konzok, Julian; Rupprecht, Rainer; Greenlee, Mark W; Mokros, Andreas; Langguth, Berthold; Poeppl, Timm B

    2015-08-01

    Sexual behavior involves motivational processes. Findings from both animal models and neuroimaging in humans suggest that the recruitment of neural motor networks is an integral part of the sexual response. However, no study so far has directly linked sexual motivation to physiologically measurable changes in cerebral motor systems in humans. Using transcranial magnetic stimulation in hetero- and homosexual men, we here show that sexual motivation modulates cortical excitability. More specifically, our results demonstrate that visual sexual stimuli corresponding with one's sexual orientation, compared with non-corresponding visual sexual stimuli, increase the excitability of the motor cortex. The reflection of sexual motivation in motor cortex excitability provides evidence for motor preparation processes in sexual behavior in humans. Moreover, such interrelationship links theoretical models and previous neuroimaging findings of sexual behavior. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  6. A Map of Anticipatory Activity in Mouse Motor Cortex.

    PubMed

    Chen, Tsai-Wen; Li, Nuo; Daie, Kayvon; Svoboda, Karel

    2017-05-17

    Activity in the mouse anterior lateral motor cortex (ALM) instructs directional movements, often seconds before movement initiation. It is unknown whether this preparatory activity is localized to ALM or widely distributed within motor cortex. Here we imaged activity across motor cortex while mice performed a whisker-based object localization task with a delayed, directional licking response. During tactile sensation and the delay epoch, object location was represented in motor cortex areas that are medial and posterior relative to ALM, including vibrissal motor cortex. Preparatory activity appeared first in deep layers of ALM, seconds before the behavioral response, and remained localized to ALM until the behavioral response. Later, widely distributed neurons represented the outcome of the trial. Cortical area was more predictive of neuronal selectivity than laminar location or axonal projection target. Motor cortex therefore represents sensory, motor, and outcome information in a spatially organized manner. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. New insights into sucking, swallowing and breathing central generators: A complexity analysis of rhythmic motor behaviors.

    PubMed

    Samson, Nathalie; Praud, Jean-Paul; Quenet, Brigitte; Similowski, Thomas; Straus, Christian

    2017-01-18

    Sucking, swallowing and breathing are dynamic motor behaviors. Breathing displays features of chaos-like dynamics, in particular nonlinearity and complexity, which take their source in the automatic command of breathing. In contrast, buccal/gill ventilation in amphibians is one of the rare motor behaviors that do not display nonlinear complexity. This study aimed at assessing whether sucking and swallowing would also follow nonlinear complex dynamics in the newborn lamb. Breathing movements were recorded before, during and after bottle-feeding. Sucking pressure and the integrated EMG of the thyroartenoid muscle, as an index of swallowing, were recorded during bottle-feeding. Nonlinear complexity of the whole signals was assessed through the calculation of the noise limit value (NL). Breathing and swallowing always exhibited chaos-like dynamics. The NL of breathing did not change significantly before, during or after bottle-feeding. On the other hand, sucking inconsistently and significantly less frequently than breathing exhibited a chaos-like dynamics. Therefore, the central pattern generator (CPG) that drives sucking may be functionally different from the breathing CPG. Furthermore, the analogy between buccal/gill ventilation and sucking suggests that the latter may take its phylogenetic origin in the gill ventilation CPG of the common ancestor of extant amphibians and mammals. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Relationship between early motor milestones and severity of restricted and repetitive behaviors in children and adolescents with autism spectrum disorder.

    PubMed

    Uljarević, Mirko; Hedley, Darren; Alvares, Gail A; Varcin, Kandice J; Whitehouse, Andrew J O

    2017-06-01

    This study explored the relationships between the later age of achievement of early motor milestones, current motor atypicalities (toe walking), and the severity of restricted and repetitive behaviors (RRBs) in individuals with autism spectrum disorder (ASD). Parents of 147 children and adolescents with ASD (M age  = 8.09 years, SD = 4.28; 119 males) completed an early developmental milestones questionnaire and the Social Responsiveness Scale as a measure of Insistence on Sameness (IS) and Repetitive Mannerisms (RM). Two hierarchical regression analyses were conducted to test whether RM and IS behaviors were predicted by early motor milestones, or current toe walking. The final model predicting RM accounted for 15% of the variance (F = 3.02, p = .009), with toe walking as a unique and independent predictor of RM scores (t = 3.568, p = .001). The final model predicting IS accounted for 19.1% of variance in IS scores (F = 4.045, p = .001), with chronological age (CA) (t = 2.92, p = .004), age when first standing (t = 2.09, p = .038), and toe walking (t = 2.53, p = .013) as unique independent predictors. Toe walking (t = 2.4, p = .018) and age when first sitting (t = 2.08, p = .04) predicted the severity of RRBs on the Autism Diagnostic Observation Schedule (F = 2.334, p = .036). Our study replicates previous findings on the relationship between concurrent motor impairments and RRBs, and provides the first evidence for the association between RRBs and age of attainment of early motor milestones. Autism Res 2017. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. Autism Res 2017, 10: 1163-1168. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

  9. Chlorpyrifos-Oxon Disrupts Zebrafish Axonal Growth and Motor Behavior

    PubMed Central

    Yang, Dongren; Lauridsen, Holly; Buels, Kalmia; Chi, Lai-Har; La Du, Jane; Bruun, Donald A.; Olson, James R.; Tanguay, Robert L.; Lein, Pamela J.

    2011-01-01

    Axonal morphology is a critical determinant of neuronal connectivity, and perturbation of the rate or extent of axonal growth during development has been linked to neurobehavioral deficits in animal models and humans. We previously demonstrated that the organophosphorus pesticide (OP) chlorpyrifos (CPF) inhibits axonal growth in cultured neurons. In this study, we used a zebrafish model to determine whether CPF, its oxon metabolite (CPFO), or the excreted metabolite trichloro-2-pyridinol (TCPy) alter spatiotemporal patterns of axonal growth in vivo. Static waterborne exposure to CPFO, but not CPF or TCPy, at concentrations ≥ 0.03μM from 24- to 72-h post fertilization significantly inhibited acetylcholinesterase, and high-performance liquid chromatography detected significantly more TCPy in zebrafish exposed to 0.1μM CPFO versus 1.0μM CPF. These data suggest that zebrafish lack the metabolic enzymes to activate CPF during these early developmental stages. Consistent with this, CPFO, but not CPF, significantly inhibited axonal growth of sensory neurons, primary motoneurons, and secondary motoneurons at concentrations ≥ 0.1μM. Secondary motoneurons were the most sensitive to axonal growth inhibition by CPFO, which was observed at concentrations that did not cause mortality, gross developmental defects, or aberrant somatic muscle differentiation. CPFO effects on axonal growth correlated with adverse effects on touch-induced swimming behavior, suggesting the functional relevance of these structural changes. These data suggest that altered patterns of neuronal connectivity contribute to the developmental neurotoxicity of CPF and demonstrate the relevance of zebrafish as a model for studying OP developmental neurotoxicity. PMID:21346248

  10. Chronic Stress Alters Striosome-Circuit Dynamics, Leading to Aberrant Decision-Making.

    PubMed

    Friedman, Alexander; Homma, Daigo; Bloem, Bernard; Gibb, Leif G; Amemori, Ken-Ichi; Hu, Dan; Delcasso, Sebastien; Truong, Timothy F; Yang, Joyce; Hood, Adam S; Mikofalvy, Katrina A; Beck, Dirk W; Nguyen, Norah; Nelson, Erik D; Toro Arana, Sebastian E; Vorder Bruegge, Ruth H; Goosens, Ki A; Graybiel, Ann M

    2017-11-16

    Effective evaluation of costs and benefits is a core survival capacity that in humans is considered as optimal, "rational" decision-making. This capacity is vulnerable in neuropsychiatric disorders and in the aftermath of chronic stress, in which aberrant choices and high-risk behaviors occur. We report that chronic stress exposure in rodents produces abnormal evaluation of costs and benefits resembling non-optimal decision-making in which choices of high-cost/high-reward options are sharply increased. Concomitantly, alterations in the task-related spike activity of medial prefrontal neurons correspond with increased activity of their striosome-predominant striatal projection neuron targets and with decreased and delayed striatal fast-firing interneuron activity. These effects of chronic stress on prefronto-striatal circuit dynamics could be blocked or be mimicked by selective optogenetic manipulation of these circuits. We suggest that altered excitation-inhibition dynamics of striosome-based circuit function could be an underlying mechanism by which chronic stress contributes to disorders characterized by aberrant decision-making under conflict. VIDEO ABSTRACT. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Multiplexing of Motor Information in the Discharge of a Collision Detecting Neuron during Escape Behaviors

    PubMed Central

    Fotowat, Haleh; Harrison, Reid R; Gabbiani, Fabrizio

    2010-01-01

    Locusts possess an identified neuron, the descending contralateral movement detector (DCMD), conveying visual information about impending collision from the brain to thoracic motor centers. We built a telemetry system to simultaneously record, in freely behaving animals, the activity of the DCMD and of motoneurons involved in jump execution. Co-contraction of antagonistic leg muscles, a required preparatory phase, was triggered after the DCMD firing rate crossed a threshold. Thereafter, the number of DCMD spikes predicted precisely motoneuron activity and jump occurrence. Additionally, the time of DCMD peak firing rate predicted that of jump. Ablation experiments suggest that the DCMD, together with a nearly identical ipsilateral descending neuron, is responsible for the timely execution of the escape. Thus, three distinct features that are multiplexed in a single neuron’s sensory response to impending collision – firing rate threshold, peak firing time, and spike count – likely control three distinct motor aspects of escape behaviors. PMID:21220105

  12. Effects of sex and housing on social, spatial, and motor behavior in adult rats exposed to moderate levels of alcohol during prenatal development

    PubMed Central

    Rodriguez, Carlos I.; Magcalas, Christy M.; Barto, Daniel; Fink, Brandi C.; Rice, James P.; Bird, Clark W.; Davies, Suzy; Pentkowski, Nathan S.; Savage, Daniel D.; Hamilton, Derek A.

    2016-01-01

    Persistent deficits in social behavior, motor behavior, and behavioral flexibility are among the major negative consequences associated with exposure to ethanol during prenatal development. Prior work from our laboratory has linked moderate prenatal alcohol exposure (PAE) in the rat to deficits in these behavioral domains, which depend upon the ventrolateral frontal cortex [20]. Manipulations of the social environment cause modifications of dendritic morphology and experience-dependent immediate early gene expression in ventrolateral frontal cortex [19], and may yield positive behavioral outcomes following PAE. In the present study we evaluated the effects of housing PAE rats with non-exposed control rats on adult behavior. Rats of both sexes were either paired with a partner from the same prenatal treatment condition (ethanol or saccharin) or from the opposite condition (mixed housing condition). At four months of age (~3 months after the housing manipulation commenced), social behavior, tongue protrusion, and behavioral flexibility in the Morris water task were measured as in [20]. The behavioral effects of moderate PAE were primarily limited to males and were not ameliorated by housing with a non-ethanol exposed partner. Unexpectedly, social behavior, motor behavior, and spatial flexibility were adversely affected in control rats housed with a PAE rat (i.e., in mixed housing), indicating that housing with a PAE rat has broad behavioral consequences beyond the social domain. These observations provide further evidence that moderate PAE negatively affects social behavior, and underscore the importance of considering potential negative effects of housing with PAE animals on the behavior of critical comparison groups. PMID:27424779

  13. Rheology of composite solid propellants during motor casting

    NASA Technical Reports Server (NTRS)

    Rogers, C. J.; Smith, P. L.; Klager, K.

    1978-01-01

    In a study conducted to evaluate flow parameters of uncured solid composite propellants during motor casting, two motors (1.8M-lb grain wt) were cast with a PBAN propellant exhibiting good flow characteristics in a 260-in. dia solid rocket motor. Attention is given to the effects of propellant compositional and processing variables on apparent viscosity as they pertain to rheological behavior and grain defect formation during casting. It is noted that optimized flow behavior is impaired with solid propellant loading. Non-Newtonian pseudoplastic flow is observed, which is dependent upon applied shear stress and the age of the uncured propellant.

  14. Auditory-Motor Control of Vocal Production during Divided Attention: Behavioral and ERP Correlates.

    PubMed

    Liu, Ying; Fan, Hao; Li, Jingting; Jones, Jeffery A; Liu, Peng; Zhang, Baofeng; Liu, Hanjun

    2018-01-01

    When people hear unexpected perturbations in auditory feedback, they produce rapid compensatory adjustments of their vocal behavior. Recent evidence has shown enhanced vocal compensations and cortical event-related potentials (ERPs) in response to attended pitch feedback perturbations, suggesting that this reflex-like behavior is influenced by selective attention. Less is known, however, about auditory-motor integration for voice control during divided attention. The present cross-modal study investigated the behavioral and ERP correlates of auditory feedback control of vocal pitch production during divided attention. During the production of sustained vowels, 32 young adults were instructed to simultaneously attend to both pitch feedback perturbations they heard and flashing red lights they saw. The presentation rate of the visual stimuli was varied to produce a low, intermediate, and high attentional load. The behavioral results showed that the low-load condition elicited significantly smaller vocal compensations for pitch perturbations than the intermediate-load and high-load conditions. As well, the cortical processing of vocal pitch feedback was also modulated as a function of divided attention. When compared to the low-load and intermediate-load conditions, the high-load condition elicited significantly larger N1 responses and smaller P2 responses to pitch perturbations. These findings provide the first neurobehavioral evidence that divided attention can modulate auditory feedback control of vocal pitch production.

  15. Spectral discrimination in color blind animals via chromatic aberration and pupil shape.

    PubMed

    Stubbs, Alexander L; Stubbs, Christopher W

    2016-07-19

    We present a mechanism by which organisms with only a single photoreceptor, which have a monochromatic view of the world, can achieve color discrimination. An off-axis pupil and the principle of chromatic aberration (where different wavelengths come to focus at different distances behind a lens) can combine to provide "color-blind" animals with a way to distinguish colors. As a specific example, we constructed a computer model of the visual system of cephalopods (octopus, squid, and cuttlefish) that have a single unfiltered photoreceptor type. We compute a quantitative image quality budget for this visual system and show how chromatic blurring dominates the visual acuity in these animals in shallow water. We quantitatively show, through numerical simulations, how chromatic aberration can be exploited to obtain spectral information, especially through nonaxial pupils that are characteristic of coleoid cephalopods. We have also assessed the inherent ambiguity between range and color that is a consequence of the chromatic variation of best focus with wavelength. This proposed mechanism is consistent with the extensive suite of visual/behavioral and physiological data that has been obtained from cephalopod studies and offers a possible solution to the apparent paradox of vivid chromatic behaviors in color blind animals. Moreover, this proposed mechanism has potential applicability in organisms with limited photoreceptor complements, such as spiders and dolphins.

  16. Spectral discrimination in color blind animals via chromatic aberration and pupil shape

    PubMed Central

    Stubbs, Alexander L.; Stubbs, Christopher W.

    2016-01-01

    We present a mechanism by which organisms with only a single photoreceptor, which have a monochromatic view of the world, can achieve color discrimination. An off-axis pupil and the principle of chromatic aberration (where different wavelengths come to focus at different distances behind a lens) can combine to provide “color-blind” animals with a way to distinguish colors. As a specific example, we constructed a computer model of the visual system of cephalopods (octopus, squid, and cuttlefish) that have a single unfiltered photoreceptor type. We compute a quantitative image quality budget for this visual system and show how chromatic blurring dominates the visual acuity in these animals in shallow water. We quantitatively show, through numerical simulations, how chromatic aberration can be exploited to obtain spectral information, especially through nonaxial pupils that are characteristic of coleoid cephalopods. We have also assessed the inherent ambiguity between range and color that is a consequence of the chromatic variation of best focus with wavelength. This proposed mechanism is consistent with the extensive suite of visual/behavioral and physiological data that has been obtained from cephalopod studies and offers a possible solution to the apparent paradox of vivid chromatic behaviors in color blind animals. Moreover, this proposed mechanism has potential applicability in organisms with limited photoreceptor complements, such as spiders and dolphins. PMID:27382180

  17. Relationships of Behavioral Measures of Frontal Lobe Dysfunction with Underlying Electrophysiology in Cocaine-Dependent Patients

    PubMed Central

    Gjini, Klevest; Qazi, Aisha; Greenwald, Mark K.; Sandhu, Ravinder; Gooding, Diane C.; Boutros, Nash N.

    2013-01-01

    Background and Objectives Despite evidence that frontal lobe functioning is impaired in cocaine-dependent individuals, relationships between behavioral measures of frontal dysfunction and electrophysiological measures of inhibition in cocaine use have not been explored. Methods Using the Frontal System Behavior Scale (FrSBe), frontal dysfunction was assessed in a group of abstinent cocaine-dependent subjects (N=49) and healthy controls (N=32). Using transcranial magnetic stimulation (TMS) and evoked potential (EP)-based electrophysiological measures of inhibition, we assessed associations between these measures and FrSBe estimates of frontal dysfunction. Results Patients had significantly higher FrSBe scores for executive dysfunction, disinhibition and apathy than controls. Lower TMS-based resting motor thresholds (i.e., hyperexcitability) were significantly associated with higher Executive Dysfunction scores in the patients. Conclusions and Scientific Significance Relationships between FrSBe scores and TMS-based measures highlight neurophysiological aberrations underlying frontal lobe dysfunction in cocaine abusers. TMS and EP measures may be useful probes of the intermediary steps between frontal lobe dysfunction and addictive behavior. PMID:24724884

  18. Image based method for aberration measurement of lithographic tools

    NASA Astrophysics Data System (ADS)

    Xu, Shuang; Tao, Bo; Guo, Yongxing; Li, Gongfa

    2018-01-01

    Information of lens aberration of lithographic tools is important as it directly affects the intensity distribution in the image plane. Zernike polynomials are commonly used for a mathematical description of lens aberrations. Due to the advantage of lower cost and easier implementation of tools, image based measurement techniques have been widely used. Lithographic tools are typically partially coherent systems that can be described by a bilinear model, which entails time consuming calculations and does not lend a simple and intuitive relationship between lens aberrations and the resulted images. Previous methods for retrieving lens aberrations in such partially coherent systems involve through-focus image measurements and time-consuming iterative algorithms. In this work, we propose a method for aberration measurement in lithographic tools, which only requires measuring two images of intensity distribution. Two linear formulations are derived in matrix forms that directly relate the measured images to the unknown Zernike coefficients. Consequently, an efficient non-iterative solution is obtained.

  19. Minimum change in spherical aberration that can be perceived

    PubMed Central

    Manzanera, Silvestre; Artal, Pablo

    2016-01-01

    It is important to know the visual sensitivity to optical blur from both a basic science perspective and a practical point of view. Of particular interest is the sensitivity to blur induced by spherical aberration because it is being used to increase depth of focus as a component of a presbyopic solution. Using a flicker detection-based procedure implemented on an adaptive optics visual simulator, we measured the spherical aberration thresholds that produce just-noticeable differences in perceived image quality. The thresholds were measured for positive and negative values of spherical aberration, for best focus and + 0.5 D and + 1.0 D of defocus. At best focus, the SA thresholds were 0.20 ± 0.01 µm and −0.17 ± 0.03 µm for positive and negative spherical aberration respectively (referred to a 6-mm pupil). These experimental values may be useful in setting spherical aberration permissible levels in different ophthalmic techniques. PMID:27699113

  20. Dopamine Promotes Motor Cortex Plasticity and Motor Skill Learning via PLC Activation

    PubMed Central

    Rioult-Pedotti, Mengia-Seraina; Pekanovic, Ana; Atiemo, Clement Osei; Marshall, John; Luft, Andreas Rüdiger

    2015-01-01

    Dopaminergic neurons in the ventral tegmental area, the major midbrain nucleus projecting to the motor cortex, play a key role in motor skill learning and motor cortex synaptic plasticity. Dopamine D1 and D2 receptor antagonists exert parallel effects in the motor system: they impair motor skill learning and reduce long-term potentiation. Traditionally, D1 and D2 receptor modulate adenylyl cyclase activity and cyclic adenosine monophosphate accumulation in opposite directions via different G-proteins and bidirectionally modulate protein kinase A (PKA), leading to distinct physiological and behavioral effects. Here we show that D1 and D2 receptor activity influences motor skill acquisition and long term synaptic potentiation via phospholipase C (PLC) activation in rat primary motor cortex. Learning a new forelimb reaching task is severely impaired in the presence of PLC, but not PKA-inhibitor. Similarly, long term potentiation in motor cortex, a mechanism involved in motor skill learning, is reduced when PLC is inhibited but remains unaffected by the PKA inhibitor. Skill learning deficits and reduced synaptic plasticity caused by dopamine antagonists are prevented by co-administration of a PLC agonist. These results provide evidence for a role of intracellular PLC signaling in motor skill learning and associated cortical synaptic plasticity, challenging the traditional view of bidirectional modulation of PKA by D1 and D2 receptors. These findings reveal a novel and important action of dopamine in motor cortex that might be a future target for selective therapeutic interventions to support learning and recovery of movement resulting from injury and disease. PMID:25938462

  1. Surface geometry and optical aberrations of ex-vivo crystalline lenses

    NASA Astrophysics Data System (ADS)

    Bueno, Juan M.; Schwarz, Christina; Acosta, Eva; Artal, Pablo

    2010-02-01

    The shape of the surfaces of ex-vivo human crystalline lenses was measured using a shadow photography technique. From these data, the back-focal distance and the contribution of each surface to the main optical aberrations of the lenses were estimated. The aberrations of the lenses were measured separately with two complementary techniques: a Hartmann-Shack wavefront sensor and a point-diffraction interferometer. A laser scanning set-up was also used to measure the actual back-focal length as well as the phase aberration in one meridian section of the lenses. Measured and predicted back-focal length agreed well within the experimental errors. The lens aberrations computed with a ray-tracing approach from the measured surfaces and geometrical data only reproduce quantitatively the measured aberrations.

  2. Sleeping on the motor engram: The multifaceted nature of sleep-related motor memory consolidation.

    PubMed

    King, Bradley R; Hoedlmoser, Kerstin; Hirschauer, Franziska; Dolfen, Nina; Albouy, Genevieve

    2017-09-01

    For the past two decades, it has generally been accepted that sleep benefits motor memory consolidation processes. This notion, however, has been challenged by recent studies and thus the sleep and motor memory story is equivocal. Currently, and in contrast to the declarative memory domain, a comprehensive overview and synthesis of the effects of post-learning sleep on the behavioral and neural correlates of motor memory consolidation is not available. We therefore provide an extensive review of the literature in order to highlight that sleep-dependent motor memory consolidation depends upon multiple boundary conditions, including particular features of the motor task, the recruitment of relevant neural substrates (and the hippocampus in particular), as well as the specific architecture of the intervening sleep period (specifically, sleep spindle and slow wave activity). For our field to continue to advance, future research must consider the multifaceted nature of sleep-related motor memory consolidation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Pyramidal tract stimulation restores normal corticospinal tract connections and visuomotor skill after early postnatal motor cortex activity blockade

    PubMed Central

    Salimi, I; Friel, KM; Martin, JH

    2008-01-01

    Motor development depends on forming specific connections between the corticospinal tract (CST) and the spinal cord. Blocking CST activity in kittens during the critical period for establishing connections with spinal motor circuits results in permanent impairments in connectivity and function. The changes in connections are consistent with the hypothesis that the inactive tract is less competitive in developing spinal connections than the active tract. In this study we tested the competition hypothesis by determining if activating CST axons, after prior silencing during the critical period, abrogated development of aberrant corticospinal connections and motor impairments. In kittens, we inactivated motor cortex by muscimol infusion between postnatal weeks 5-7. We next electrically stimulated CST axons in the medullary pyramid 2.5 hours daily, between weeks 7-10. In controls (n=3), CST terminations were densest within the contralateral deeper, premotor, spinal layers. After prior inactivation (n=3), CST terminations were densest within the dorsal, somatic sensory, layers. There were more ipsilateral terminations from the active tract. During visually guided locomotion, there was a movement endpoint impairment. Stimulation after inactivation (n=6) resulted in significantly fewer terminations in the sensory layers and more in the premotor layers, and fewer ipsilateral connections from active cortex. Chronic stimulation reduced the current threshold for evoking contralateral movements by pyramidal stimulation, suggesting strengthening of connections. Importantly, stimulation significantly improved stepping accuracy. These findings show the importance of activity-dependent processes in specifying CST connections. They also provide a strategy for harnessing activity to rescue CST axons at risk of developing aberrant connections after CNS injury. PMID:18632946

  4. Genotoxicity of mercury used in chromosome aberration tests.

    PubMed

    Akiyama, M; Oshima, H; Nakamura, M

    2001-01-01

    The purpose of this study was to investigate the genotoxic effects of Hg released from dental amalgams. The chromosome aberration test was conducted using original extracts and their diluted solutions of conventional type amalgam and high copper amalgam. The concentrations of Hg, Cu and Ag in the original extract of high copper amalgam were 17.64, 7.97 and 43.90 microM, respectively. Those in the original extract of conventional type amalgam were 20.63, 7.87 and 14.79 microM, respectively. 10 and 30 microM Hg(2+) were also used for comparison. The frequency of chromosome aberrations was below 5% with 0 microM Hg(2+) and with a triple dilution of high copper amalgam extract, containing 5.88 microM Hg, 14.63 microM Cu and 2.65 microM Ag. However, 9.5% of the cells showed chromosome aberrations with a quadruple dilution of conventional type amalgam, containing 5.15 microM Hg, 3.69 microM Cu and 1.96 microM Ag. The amount of Hg in the quadruple dilution of conventional type amalgam was less than that in the triple dilution of high copper amalgam extract and 10 microM Hg(2+). A concentration of 30 microM Hg(2+) caused 34.5% of the cells to show chromosome aberrations while with a two-thirds dilution of high copper amalgam extract, containing 11.76 microM Hg, 29.26 microM Cu and 5.31 microM Ag, 58.5% of the cells showed chromosome aberrations. A two-thirds dilution of high copper amalgam extract induced more chromosome aberrations than 30 microM Hg(2+), although the amount of Hg was less than 30 microM Hg(2+). A triple dilution of conventional type amalgam extract, original extracts of conventional type amalgam and high copper amalgam and 100 microM Hg(2+) were induced few metaphases. It was revealed that the conventional type amalgam induced chromosome aberrations with quadruple dilution where cell viability was about 80% and that the high copper amalgam induced a high level of chromosome aberrations with the two-thirds dilution. The effects of low level Hg on humans

  5. Movement Sonification: Effects on Motor Learning beyond Rhythmic Adjustments.

    PubMed

    Effenberg, Alfred O; Fehse, Ursula; Schmitz, Gerd; Krueger, Bjoern; Mechling, Heinz

    2016-01-01

    Motor learning is based on motor perception and emergent perceptual-motor representations. A lot of behavioral research is related to single perceptual modalities but during last two decades the contribution of multimodal perception on motor behavior was discovered more and more. A growing number of studies indicates an enhanced impact of multimodal stimuli on motor perception, motor control and motor learning in terms of better precision and higher reliability of the related actions. Behavioral research is supported by neurophysiological data, revealing that multisensory integration supports motor control and learning. But the overwhelming part of both research lines is dedicated to basic research. Besides research in the domains of music, dance and motor rehabilitation, there is almost no evidence for enhanced effectiveness of multisensory information on learning of gross motor skills. To reduce this gap, movement sonification is used here in applied research on motor learning in sports. Based on the current knowledge on the multimodal organization of the perceptual system, we generate additional real-time movement information being suitable for integration with perceptual feedback streams of visual and proprioceptive modality. With ongoing training, synchronously processed auditory information should be initially integrated into the emerging internal models, enhancing the efficacy of motor learning. This is achieved by a direct mapping of kinematic and dynamic motion parameters to electronic sounds, resulting in continuous auditory and convergent audiovisual or audio-proprioceptive stimulus arrays. In sharp contrast to other approaches using acoustic information as error-feedback in motor learning settings, we try to generate additional movement information suitable for acceleration and enhancement of adequate sensorimotor representations and processible below the level of consciousness. In the experimental setting, participants were asked to learn a closed

  6. Movement Sonification: Effects on Motor Learning beyond Rhythmic Adjustments

    PubMed Central

    Effenberg, Alfred O.; Fehse, Ursula; Schmitz, Gerd; Krueger, Bjoern; Mechling, Heinz

    2016-01-01

    Motor learning is based on motor perception and emergent perceptual-motor representations. A lot of behavioral research is related to single perceptual modalities but during last two decades the contribution of multimodal perception on motor behavior was discovered more and more. A growing number of studies indicates an enhanced impact of multimodal stimuli on motor perception, motor control and motor learning in terms of better precision and higher reliability of the related actions. Behavioral research is supported by neurophysiological data, revealing that multisensory integration supports motor control and learning. But the overwhelming part of both research lines is dedicated to basic research. Besides research in the domains of music, dance and motor rehabilitation, there is almost no evidence for enhanced effectiveness of multisensory information on learning of gross motor skills. To reduce this gap, movement sonification is used here in applied research on motor learning in sports. Based on the current knowledge on the multimodal organization of the perceptual system, we generate additional real-time movement information being suitable for integration with perceptual feedback streams of visual and proprioceptive modality. With ongoing training, synchronously processed auditory information should be initially integrated into the emerging internal models, enhancing the efficacy of motor learning. This is achieved by a direct mapping of kinematic and dynamic motion parameters to electronic sounds, resulting in continuous auditory and convergent audiovisual or audio-proprioceptive stimulus arrays. In sharp contrast to other approaches using acoustic information as error-feedback in motor learning settings, we try to generate additional movement information suitable for acceleration and enhancement of adequate sensorimotor representations and processible below the level of consciousness. In the experimental setting, participants were asked to learn a closed

  7. The effects of poliomyelitis on motor unit behavior during repetitive muscle actions: a case report.

    PubMed

    Trevino, Michael A; Herda, Trent J; Cooper, Michael A

    2014-09-06

    Acute paralytic poliomyelitis is caused by the poliovirus and usually results in muscle atrophy and weakness occurring in the lower limbs. Indwelling electromyography has been used frequently to investigate the denervation and innervation characteristics of the affected muscle. Recently developed technology allows the decomposition of the raw surface electromyography signals into the firing instances of single motor units. There is limited information regarding this electromyographic decomposition in clinical populations. In addition, regardless of electromyographic methods, no study has examined muscle activation parameters during repetitive muscle actions in polio patients. Therefore, the purpose of this study was to examine the motor unit firing rates and electromyographic amplitude and center frequency of the vastus lateralis during 20 repetitive isometric muscle actions at 50% maximal voluntary contraction in healthy subjects and one patient that acquired acute paralytic poliomyelitis. One participant that acquired acute type III spinal poliomyelitis (Caucasian male, age = 29 yrs) at 3 months of age and three healthy participants (Caucasian females, age = 19.7 ± 2.1 yrs) participated in this study. The polio participant reported neuromuscular deficiencies as a result of disease in the hips, knees, buttocks, thighs, and lower legs. None of the healthy participants reported any current or ongoing neuromuscular diseases or musculoskeletal injuries. An acute bout of poliomyelitis altered motor unit behavior, such as, healthy participants displayed greater firing rates than the polio patient. The reduction in motor unit firing rates was likely a fatigue protecting mechanism since denervation via poliomyelitis results in a reduction of motorneurons. In addition, the concurrent changes in motor unit firing rates, electromyography amplitude and frequency for the polio participant would suggest that the entire motorneuron pool was utilized in each contraction unlike

  8. An Exploratory Examination of the Association Between Altered Lumbar Motor Control, Joint Mobility and Low Back Pain in Athletes

    PubMed Central

    Corkery, Marie B.; O’Rourke, Brittany; Viola, Samantha; Yen, Sheng-Che; Rigby, Joseph; Singer, Kevin; Thomas, Adam

    2014-01-01

    Background: Low back pain (LBP) is a common cause of lost playing time and can be a challenging clinical condition in competitive athletes. LBP in athletes may be associated with joint and ligamentous hypermobility and impairments in activation and coordination of the trunk musculature, however there is limited research in this area. Objectives: To determine if there is an association between altered lumbar motor control, joint mobility and low back pain (LBP) in a sample of athletes. Materials and Methods: Fifteen athletes with LBP were matched by age, gender and body mass index (BMI) with controls without LBP. Athletes completed a questionnaire with questions pertaining to demographics, activity level, medical history, need to self-manipulate their spine, pain intensity and location. Flexibility and lumbar motor control were assessed using: active and passive straight leg raise, lumbar range of motion (ROM), hip internal rotation ROM (HIR), Beighton ligamentous laxity scale, prone instability test (PIT), observation of lumbar aberrant movements, double leg lowering and Trendelenburg tests. Descriptive statistics were compiled and the chi square test was used to analyze results. Results: Descriptive statistics showed that 40% of athletes with LBP exhibited aberrant movements (AM), compared to 6% without LBP. 66% of athletes with LBP reported frequently self-manipulating their spine compared to 40% without LBP. No significant differences in motor control tests were found between groups. Athletes with LBP tended to have less lumbar flexion (63 ± 11°) compared to those without LBP (66 ± 13°). Chi-Square tests revealed that the AM were more likely to be present in athletes with LBP than those without (X2 = 4.66, P = 0.03). Conclusions: The presence of aberrant movement patterns is a significant clinical finding and associated with LBP in athletes. PMID:25741418

  9. Optical aberrations, retinal image quality and eye growth: Experimentation and modeling

    NASA Astrophysics Data System (ADS)

    Tian, Yibin

    2007-12-01

    Retinal image quality is important for normal eye growth. Optical aberrations are of interest for two reasons: first, they degrade retinal images; second, they might provide some cues to defocus. Higher than normal ocular aberrations have been previously associated with human myopia. However, these studies were cross-sectional in design, and only reported aberrations in terms of root mean square (RMS) errors of Zernike coefficients, a poor metric of optical quality. This dissertation presents results from investigations of ocular optical aberrations, retinal image quality and eye growth in chicks and humans. A number of techniques were utilized, including Shack-Hartmann aberrometry, high-frequency A-scan ultrasonography, ciliary nerve section (CNX), photorefractive keratectomy (PRK) as well as computer simulations and modeling. A technique to extract light scatter information from Shack-Hartmann images was also developed. The main findings of the dissertation are summarized below. In young chicks, most ocular aberrations decreased with growth in both normal and CNX eyes, and there were diurnal fluctuations in some aberrations. Modeling suggested active reduction in higher order aberrations (HOAs) during early development. Although CNX eyes manifested greater than normal HOAs, they showed near normal growth. Retinal image degradation varied greatly among individual eyes post-PRK in young chicks. Including light scatter information into analyses of retinal image quality better estimated the latter. Albino eyes showed more severe retinal image degradation than normal eyes, due to increased optical aberrations and light scatter, but their growth was similar to those of normal eyes, implying that they are relatively insensitive to retina image quality. Although the above results questioned the influence of optical aberrations on early ocular growth, some optical quality metrics, derived from optical aberrations data, could predict how much the eyes of young chicks

  10. Evolution of Motor Control: From Reflexes and Motor Programs to the Equilibrium-Point Hypothesis

    PubMed Central

    Latash, Mark L.

    2009-01-01

    This brief review analyzes the evolution of motor control theories along two lines that emphasize active (motor programs) and reactive (reflexes) features of voluntary movements. It suggests that the only contemporary hypothesis that integrates both approaches in a fruitful way is the equilibrium-point hypothesis. Physical, physiological, and behavioral foundations of the EP-hypothesis are considered as well as relations between the EP-hypothesis and the recent developments of the notion of motor synergies. The paper ends with a brief review of the criticisms of the EP-hypothesis and challenges that the hypothesis faces at this time. PMID:19823595

  11. Evolution of Motor Control: From Reflexes and Motor Programs to the Equilibrium-Point Hypothesis.

    PubMed

    Latash, Mark L

    2008-01-01

    This brief review analyzes the evolution of motor control theories along two lines that emphasize active (motor programs) and reactive (reflexes) features of voluntary movements. It suggests that the only contemporary hypothesis that integrates both approaches in a fruitful way is the equilibrium-point hypothesis. Physical, physiological, and behavioral foundations of the EP-hypothesis are considered as well as relations between the EP-hypothesis and the recent developments of the notion of motor synergies. The paper ends with a brief review of the criticisms of the EP-hypothesis and challenges that the hypothesis faces at this time.

  12. Correcting highly aberrated eyes using large-stroke adaptive optics.

    PubMed

    Sabesan, Ramkumar; Ahmad, Kamran; Yoon, Geunyoung

    2007-11-01

    To investigate the optical performance of a large-stroke deformable mirror in correcting large aberrations in highly aberrated eyes. A large-stroke deformable mirror (Mirao 52D; Imagine Eyes) and a Shack-Hartmann wavefront sensor were used in an adaptive optics system. Closed-loop correction of the static aberrations of a phase plate designed for an advanced keratoconic eye was performed for a 6-mm pupil. The same adaptive optics system was also used to correct the aberrations in one eye each of two moderate keratoconic and three normal human eyes for a 6-mm pupil. With closed-loop correction of the phase plate, the total root-mean-square (RMS) over a 6-mm pupil was reduced from 3.54 to 0.04 microm in 30 to 40 iterations, corresponding to 3 to 4 seconds. Adaptive optics closed-loop correction reduced an average total RMS of 1.73+/-0.998 to 0.10+/-0.017 microm (higher order RMS of 0.39+/-0.124 to 0.06+/-0.004 microm) in the three normal eyes and 2.73+/-1.754 to 0.10+/-0.001 microm (higher order RMS of 1.82+/-1.058 to 0.05+/-0.017 microm) in the two keratoconic eyes. Aberrations in both normal and highly aberrated eyes were successfully corrected using the large-stroke deformable mirror to provide almost perfect optical quality. This mirror can be a powerful tool to assess the limit of visual performance achievable after correcting the aberrations, especially in eyes with abnormal corneal profiles.

  13. Subjective face recognition difficulties, aberrant sensibility, sleeping disturbances and aberrant eating habits in families with Asperger syndrome

    PubMed Central

    Nieminen-von Wendt, Taina; Paavonen, Juulia E; Ylisaukko-Oja, Tero; Sarenius, Susan; Källman, Tiia; Järvelä, Irma; von Wendt, Lennart

    2005-01-01

    Background The present study was undertaken in order to determine whether a set of clinical features, which are not included in the DSM-IV or ICD-10 for Asperger Syndrome (AS), are associated with AS in particular or whether they are merely a familial trait that is not related to the diagnosis. Methods Ten large families, a total of 138 persons, of whom 58 individuals fulfilled the diagnostic criteria for AS and another 56 did not to fulfill these criteria, were studied using a structured interview focusing on the possible presence of face recognition difficulties, aberrant sensibility and eating habits and sleeping disturbances. Results The prevalence for face recognition difficulties was 46.6% in individuals with AS compared with 10.7% in the control group. The corresponding figures for subjectively reported presence of aberrant sensibilities were 91.4% and 46.6%, for sleeping disturbances 48.3% and 23.2% and for aberrant eating habits 60.3% and 14.3%, respectively. Conclusion An aberrant processing of sensory information appears to be a common feature in AS. The impact of these and other clinical features that are not incorporated in the ICD-10 and DSM-IV on our understanding of AS may hitherto have been underestimated. These associated clinical traits may well be reflected by the behavioural characteristics of these individuals. PMID:15826308

  14. High Working Memory Load Increases Intracortical Inhibition in Primary Motor Cortex and Diminishes the Motor Affordance Effect.

    PubMed

    Freeman, Scott M; Itthipuripat, Sirawaj; Aron, Adam R

    2016-05-18

    Motor affordances occur when the visual properties of an object elicit behaviorally relevant motor representations. Typically, motor affordances only produce subtle effects on response time or on motor activity indexed by neuroimaging/neuroelectrophysiology, but sometimes they can trigger action itself. This is apparent in "utilization behavior," where individuals with frontal cortex damage inappropriately grasp affording objects. This raises the possibility that, in healthy-functioning individuals, frontal cortex helps ensure that irrelevant affordance provocations remain below the threshold for actual movement. In Experiment 1, we tested this "frontal control" hypothesis by "loading" the frontal cortex with an effortful working memory (WM) task (which ostensibly consumes frontal resources) and examined whether this increased EEG measures of motor affordances to irrelevant affording objects. Under low WM load, there were typical motor affordance signatures: an event-related desynchronization in the mu frequency and an increased P300 amplitude for affording (vs nonaffording) objects over centroparietal electrodes. Contrary to our prediction, however, these affordance measures were diminished under high WM load. In Experiment 2, we tested competing mechanisms responsible for the diminished affordance in Experiment 1. We used paired-pulse transcranial magnetic stimulation over primary motor cortex to measure long-interval cortical inhibition. We found greater long-interval cortical inhibition for high versus low load both before and after the affording object, suggesting that a tonic inhibition state in primary motor cortex could prevent the affordance from provoking the motor system. Overall, our results suggest that a high WM load "sets" the motor system into a suppressed state that mitigates motor affordances. Is an irrelevant motor affordance more likely to be triggered when you are under low or high cognitive load? We examined this using physiological measures

  15. Spectral estimation for characterization of acoustic aberration.

    PubMed

    Varslot, Trond; Angelsen, Bjørn; Waag, Robert C

    2004-07-01

    Spectral estimation based on acoustic backscatter from a motionless stochastic medium is described for characterization of aberration in ultrasonic imaging. The underlying assumptions for the estimation are: The correlation length of the medium is short compared to the length of the transmitted acoustic pulse, an isoplanatic region of sufficient size exists around the focal point, and the backscatter can be modeled as an ergodic stochastic process. The motivation for this work is ultrasonic imaging with aberration correction. Measurements were performed using a two-dimensional array system with 80 x 80 transducer elements and an element pitch of 0.6 mm. The f number for the measurements was 1.2 and the center frequency was 3.0 MHz with a 53% bandwidth. Relative phase of aberration was extracted from estimated cross spectra using a robust least-mean-square-error method based on an orthogonal expansion of the phase differences of neighboring wave forms as a function of frequency. Estimates of cross-spectrum phase from measurements of random scattering through a tissue-mimicking aberrator have confidence bands approximately +/- 5 degrees wide. Both phase and magnitude are in good agreement with a reference characterization obtained from a point scatterer.

  16. Bridging the gap between motor imagery and motor execution with a brain-robot interface.

    PubMed

    Bauer, Robert; Fels, Meike; Vukelić, Mathias; Ziemann, Ulf; Gharabaghi, Alireza

    2015-03-01

    According to electrophysiological studies motor imagery and motor execution are associated with perturbations of brain oscillations over spatially similar cortical areas. By contrast, neuroimaging and lesion studies suggest that at least partially distinct cortical networks are involved in motor imagery and execution. We sought to further disentangle this relationship by studying the role of brain-robot interfaces in the context of motor imagery and motor execution networks. Twenty right-handed subjects performed several behavioral tasks as indicators for imagery and execution of movements of the left hand, i.e. kinesthetic imagery, visual imagery, visuomotor integration and tonic contraction. In addition, subjects performed motor imagery supported by haptic/proprioceptive feedback from a brain-robot-interface. Principal component analysis was applied to assess the relationship of these indicators. The respective cortical resting state networks in the α-range were investigated by electroencephalography using the phase slope index. We detected two distinct abilities and cortical networks underlying motor control: a motor imagery network connecting the left parietal and motor areas with the right prefrontal cortex and a motor execution network characterized by transmission from the left to right motor areas. We found that a brain-robot-interface might offer a way to bridge the gap between these networks, opening thereby a backdoor to the motor execution system. This knowledge might promote patient screening and may lead to novel treatment strategies, e.g. for the rehabilitation of hemiparesis after stroke. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. The aging motor system as a model for plastic changes of GABA-mediated intracortical inhibition and their behavioral relevance.

    PubMed

    Heise, Kirstin-F; Zimerman, Maximo; Hoppe, Julia; Gerloff, Christian; Wegscheider, Karl; Hummel, Friedhelm C

    2013-05-22

    Since GABAA-mediated intracortical inhibition has been shown to underlie plastic changes throughout the lifespan from development to aging, here, the aging motor system was used as a model to analyze the interdependence of plastic alterations within the inhibitory motorcortical network and level of behavioral performance. Double-pulse transcranial magnetic stimulation (dpTMS) was used to examine inhibition by means of short-interval intracortical inhibition (SICI) of the contralateral primary motor cortex in a sample of 64 healthy right-handed human subjects covering a wide range of the adult lifespan (age range 20-88 years, mean 47.6 ± 20.7, 34 female). SICI was evaluated during resting state and in an event-related condition during movement preparation in a visually triggered simple reaction time task. In a subgroup (N = 23), manual motor performance was tested with tasks of graded dexterous demand. Weak resting-state inhibition was associated with an overall lower manual motor performance. Better event-related modulation of inhibition correlated with better performance in more demanding tasks, in which fast alternating activation of cortical representations are necessary. Declining resting-state inhibition was associated with weakened event-related modulation of inhibition. Therefore, reduced resting-state inhibition might lead to a subsequent loss of modulatory capacity, possibly reflecting malfunctioning precision in GABAAergic neurotransmission; the consequence is an inevitable decline in motor function.

  18. Statistical virtual eye model based on wavefront aberration

    PubMed Central

    Wang, Jie-Mei; Liu, Chun-Ling; Luo, Yi-Ning; Liu, Yi-Guang; Hu, Bing-Jie

    2012-01-01

    Wavefront aberration affects the quality of retinal image directly. This paper reviews the representation and reconstruction of wavefront aberration, as well as the construction of virtual eye model based on Zernike polynomial coefficients. In addition, the promising prospect of virtual eye model is emphasized. PMID:23173112

  19. Double-pass measurement of human eye aberrations: limitations and practical realization

    NASA Astrophysics Data System (ADS)

    Letfullin, Renat R.; Belyakov, Alexey I.; Cherezova, Tatyana Y.; Kudryashov, Alexis V.

    2004-11-01

    The problem of correct eye aberrations measurement is very important with the rising widespread of a surgical procedure for reducing refractive error in the eye, so called, LASIK (laser-assisted in situ keratomileusis). The double-pass technique commonly used for measuring aberrations of a human eye involves some uncertainties. One of them is loosing the information about odd human eye aberrations. We report about investigations of the applicability limit of the double-pass measurements depending upon the aberrations status introduced by human eye and actual size of the entrance pupil. We evaluate the double-pass effects for various aberrations and different pupil diameters. It is shown that for small pupils the double-pass effects are negligible. The testing and alignment of aberrometer was performed using the schematic eye, developed in our lab. We also introduced a model of human eye based on bimorph flexible mirror. We perform calculations to demonstrate that our schematic eye is capable of reproducing spatial-temporal statistics of aberrations of living eye with normal vision or even myopic or hypermetropic or with high aberrations ones.

  20. Effects of Risperidone on Cognitive-Motor Performance and Motor Movements in Chronically Medicated Children

    ERIC Educational Resources Information Center

    Aman, Michael G.; Hollway, Jill A.; Leone, Sarah; Masty, Jessica; Lindsay, Ronald; Nash, Patricia; Arnold, L. Eugene

    2009-01-01

    This study was designed to explore the placebo-controlled effects of risperidone on cognitive-motor processes, dyskinetic movements, and behavior in children receiving maintenance risperidone therapy. Sixteen children aged 4-14 years with disruptive behavior were randomly assigned to drug order in a crossover study of risperidone and placebo for 2…

  1. Social Motor Synchronization: Insights for Understanding Social Behavior in Autism

    ERIC Educational Resources Information Center

    Fitzpatrick, Paula; Romero, Veronica; Amaral, Joseph L.; Duncan, Amie; Barnard, Holly; Richardson, Michael J.; Schmidt, R. C.

    2017-01-01

    Impairments in social interaction and communication are critical features of ASD but the underlying processes are poorly understood. An under-explored area is the social motor synchronization that happens when we coordinate our bodies with others. Here, we explored the relationships between dynamical measures of social motor synchronization and…

  2. Motor heuristics and embodied choices: how to choose and act.

    PubMed

    Raab, Markus

    2017-08-01

    Human performance requires choosing what to do and how to do it. The goal of this theoretical contribution is to advance understanding of how the motor and cognitive components of choices are intertwined. From a holistic perspective I extend simple heuristics that have been tested in cognitive tasks to motor tasks, coining the term motor heuristics. Similarly I extend the concept of embodied cognition, that has been tested in simple sensorimotor processes changing decisions, to complex sport behavior coining the term embodied choices. Thus both motor heuristics and embodied choices explain complex behavior such as studied in sport and exercise psychology. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Fundamental motor skill, physical activity, and sedentary behavior in socioeconomically disadvantaged kindergarteners.

    PubMed

    Gu, Xiangli

    2016-10-01

    Guided by Stodden et al's conceptual model, the main purpose of the study was to examine the relation between fundamental motor skills (FMS; locomotor and objective control skills), different intensity levels of physical activity (light PA [LPA], moderate-to-vigorous PA [MVPA], and vigorous PA[VPA]), and sedentary behavior (SB) in socioeconomically disadvantaged kindergarteners. A prospective design was used in this study and the data were collected across the 2013-2014 academic school year. Participants were 256 (129 boys; 127 girls; Mage = 5.37, SD = 0.48) kindergarteners recruited from three public schools in the southern United States. Results found that FMS were significantly related to LPA, MVPA, VPA, and SB. Regression analyses indicate that locomotor skills explained significant variance for LPA (6.4%; p < .01), MVPA (7.9%; p < .001), and VPA (5.3%; p < .01) after controlling for weight status. Mediational analysis supports the significant indirect effect of MVPA on the relation between FMS and SB (95% CI: [-0.019, -0.006]). Adequate FMS development during early childhood may result in participating in more varied physical activities, thus leading to lower risk of obesity-related behaviors.

  4. Aberrant connections between climbing fibres and Purkinje cells induce alterations in the timing of an instrumental response in the rat.

    PubMed

    Gaytán-Tocavén, Lorena; López-Vázquez, Miguel Ángel; Guevara, Miguel Ángel; Olvera-Cortés, María Esther

    2017-09-01

    Cerebellar participation in timing and sensory-motor sequences has been supported by several experimental and clinical studies. A relevant role of the cerebellum in timing of conditioned responses in the range of milliseconds has been demonstrated, but less is known regarding the role of the cerebellum in supra-second timing of operant responses. A dissociated role of the cerebellum and striatum in timing in the millisecond and second range had been reported, respectively. The climbing fibre-Purkinje cell synapse is crucial in timing models; thus, the aberrant connection between these cellular elements is a suitable model for evaluating the contribution of the cerebellum in timing in the supra-second range. The aberrant connection between climbing fibres and Purkinje cells was induced by administration of the antagonist of NMDA receptors MK-801 to Sprague-Dawley rats at postnatal days 7-14. The timing of an operant response with two fixed intervals (5 and 8 s) and egocentric sequential learning was evaluated in 60-day-old adult rats. The aberrant connections caused a reduced accuracy in the timing of the instrumental response that was more evident in the 8-s interval and a reduced number of successive correct responses (responses emitted in the correct second without any other response between them) in the 8-s interval. In addition, an inability to incorporate new information in a sequence previously learned in egocentric-based sequence learning was apparent in rats with aberrant CF-PC synapses. These results support a relevant role for the cerebellum in the fine-tuning of the timing of operant responses in the supra-second range.

  5. Ocular Chromatic Aberrations and Their Effects on Polychromatic Retinal Image Quality

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoxiao

    Previous studies of ocular chromatic aberrations have concentrated on chromatic difference of focus (CDF). Less is known about the chromatic difference of image position (CDP) in the peripheral retina and no experimental attempt has been made to measure the ocular chromatic difference of magnification (CDM). Consequently, theoretical modelling of human eyes is incomplete. The insufficient knowledge of ocular chromatic aberrations is partially responsible for two unsolved applied vision problems: (1) how to improve vision by correcting ocular chromatic aberration? (2) what is the impact of ocular chromatic aberration on the use of isoluminance gratings as a tool in spatial-color vision?. Using optical ray tracing methods, MTF analysis methods of image quality, and psychophysical methods, I have developed a more complete model of ocular chromatic aberrations and their effects on vision. The ocular CDM was determined psychophysically by measuring the tilt in the apparent frontal parallel plane (AFPP) induced by interocular difference in image wavelength. This experimental result was then used to verify a theoretical relationship between the ocular CDM, the ocular CDF and the entrance pupil of the eye. In the retinal image after correcting the ocular CDF with existing achromatizing methods, two forms of chromatic aberration (CDM and chromatic parallax) were examined. The CDM was predicted by theoretical ray tracing and measured with the same method used to determine ocular CDM. The chromatic parallax was predicted with a nodal ray model and measured with the two-color vernier alignment method. The influence of these two aberrations on polychromatic MTF were calculated. Using this improved model of ocular chromatic aberration, luminance artifacts in the images of isoluminance gratings were calculated. The predicted luminance artifacts were then compared with experimental data from previous investigators. The results show that: (1) A simple relationship exists between

  6. Focal Stroke in the Developing Rat Motor Cortex Induces Age- and Experience-Dependent Maladaptive Plasticity of Corticospinal System

    PubMed Central

    Gennaro, Mariangela; Mattiello, Alessandro; Mazziotti, Raffaele; Antonelli, Camilla; Gherardini, Lisa; Guzzetta, Andrea; Berardi, Nicoletta; Cioni, Giovanni; Pizzorusso, Tommaso

    2017-01-01

    Motor system development is characterized by an activity-dependent competition between ipsilateral and contralateral corticospinal tracts (CST). Clinical evidence suggests that age is crucial for developmental stroke outcome, with early lesions inducing a “maladaptive” strengthening of ipsilateral projections from the healthy hemisphere and worse motor impairment. Here, we investigated in developing rats the relation between lesion timing, motor outcome and CST remodeling pattern. We induced a focal ischemia into forelimb motor cortex (fM1) at two distinct pre-weaning ages: P14 and P21. We compared long-term motor outcome with changes in axonal sprouting of contralesional CST at red nucleus and spinal cord level using anterograde tracing. We found that P14 stroke caused a more severe long-term motor impairment than at P21, and induced a strong and aberrant contralesional CST sprouting onto denervated spinal cord and red nucleus. The mistargeted sprouting of CST, and the worse motor outcome of the P14 stroke rats were reversed by an early skilled motor training, underscoring the potential of early activity-dependent plasticity in modulating lesion outcome. Thus, changes in the mechanisms controlling CST plasticity occurring during the third postnatal week are associated with age-dependent regulation of the motor outcome after stroke. PMID:28706475

  7. Focal Stroke in the Developing Rat Motor Cortex Induces Age- and Experience-Dependent Maladaptive Plasticity of Corticospinal System.

    PubMed

    Gennaro, Mariangela; Mattiello, Alessandro; Mazziotti, Raffaele; Antonelli, Camilla; Gherardini, Lisa; Guzzetta, Andrea; Berardi, Nicoletta; Cioni, Giovanni; Pizzorusso, Tommaso

    2017-01-01

    Motor system development is characterized by an activity-dependent competition between ipsilateral and contralateral corticospinal tracts (CST). Clinical evidence suggests that age is crucial for developmental stroke outcome, with early lesions inducing a "maladaptive" strengthening of ipsilateral projections from the healthy hemisphere and worse motor impairment. Here, we investigated in developing rats the relation between lesion timing, motor outcome and CST remodeling pattern. We induced a focal ischemia into forelimb motor cortex (fM1) at two distinct pre-weaning ages: P14 and P21. We compared long-term motor outcome with changes in axonal sprouting of contralesional CST at red nucleus and spinal cord level using anterograde tracing. We found that P14 stroke caused a more severe long-term motor impairment than at P21, and induced a strong and aberrant contralesional CST sprouting onto denervated spinal cord and red nucleus. The mistargeted sprouting of CST, and the worse motor outcome of the P14 stroke rats were reversed by an early skilled motor training, underscoring the potential of early activity-dependent plasticity in modulating lesion outcome. Thus, changes in the mechanisms controlling CST plasticity occurring during the third postnatal week are associated with age-dependent regulation of the motor outcome after stroke.

  8. Orthonormal aberration polynomials for anamorphic optical imaging systems with circular pupils.

    PubMed

    Mahajan, Virendra N

    2012-06-20

    In a recent paper, we considered the classical aberrations of an anamorphic optical imaging system with a rectangular pupil, representing the terms of a power series expansion of its aberration function. These aberrations are inherently separable in the Cartesian coordinates (x,y) of a point on the pupil. Accordingly, there is x-defocus and x-coma, y-defocus and y-coma, and so on. We showed that the aberration polynomials orthonormal over the pupil and representing balanced aberrations for such a system are represented by the products of two Legendre polynomials, one for each of the two Cartesian coordinates of the pupil point; for example, L(l)(x)L(m)(y), where l and m are positive integers (including zero) and L(l)(x), for example, represents an orthonormal Legendre polynomial of degree l in x. The compound two-dimensional (2D) Legendre polynomials, like the classical aberrations, are thus also inherently separable in the Cartesian coordinates of the pupil point. Moreover, for every orthonormal polynomial L(l)(x)L(m)(y), there is a corresponding orthonormal polynomial L(l)(y)L(m)(x) obtained by interchanging x and y. These polynomials are different from the corresponding orthogonal polynomials for a system with rotational symmetry but a rectangular pupil. In this paper, we show that the orthonormal aberration polynomials for an anamorphic system with a circular pupil, obtained by the Gram-Schmidt orthogonalization of the 2D Legendre polynomials, are not separable in the two coordinates. Moreover, for a given polynomial in x and y, there is no corresponding polynomial obtained by interchanging x and y. For example, there are polynomials representing x-defocus, balanced x-coma, and balanced x-spherical aberration, but no corresponding y-aberration polynomials. The missing y-aberration terms are contained in other polynomials. We emphasize that the Zernike circle polynomials, although orthogonal over a circular pupil, are not suitable for an anamorphic system as

  9. Fetal behavioral teratology.

    PubMed

    Visser, Gerard H A; Mulder, Eduard J H; Tessa Ververs, F F

    2010-10-01

    Ultrasound studies of fetal motor behavior provide direct – in vivo – insight in the functioning of the motor component of the fetal central nervous system. In this article, studies are reviewed showing changes in the first timetable of appearance of fetal movements, changes in quality and/or quantity of movements and disturbances in the development of fetal behavioral states in case of endogenous malfunctions, maternal diseases and exogenous behavioral teratogens.

  10. Seemingly irrational driving behavior model: The effect of habit strength and anticipated affective reactions.

    PubMed

    Chung, Yi-Shih

    2015-09-01

    An increasing amount of evidence suggests that aberrant driving behaviors are not entirely rational. On the basis of the dual-process theory, this study postulates that drivers may learn to perform irrational aberrant driving behaviors, and these behaviors could be derived either from a deliberate or an intuitive decision-making approach. Accordingly, a seemingly irrational driving behavior model is proposed; in this model, the theory of planned behavior (TPB) was adopted to represent the deliberate decision-making mechanism, and habit strength was incorporated to reflect the intuitive decision process. A multiple trivariate mediation structure was designed to reflect the process through which driving behaviors are learned. Anticipated affective reactions (AARs) were further included to examine the effect of affect on aberrant driving behaviors. Considering the example of speeding behaviors, this study developed scales and conducted a two-wave survey of students in two departments at a university in Northern Taiwan. The analysis results show that habit strength consists of multiple aspects, and frequency of past behavior cannot be a complete repository for accumulating habit strength. Habit strength appeared to be a crucial mediator between intention antecedents (e.g., attitude) and the intention itself. Including habit strength in the TPB model enhanced the explained variance of speeding intention by 26.7%. In addition, AARs were different from attitudes; particularly, young drivers tended to perform speeding behaviors to reduce negative feelings such as regret. The proposed model provides an effective alternative approach for investigating aberrant driving behaviors; corresponding countermeasures are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Motor Control Research Requires Nonlinear Dynamics

    ERIC Educational Resources Information Center

    Guastello, Stephen J.

    2006-01-01

    The author comments on the original article "The Cinderella of psychology: The neglect of motor control in the science of mental life and behavior," by D. A. Rosenbaum. Rosenbaum draws attention to the study of motor control and evaluates seven possible explanations for why the topic has been relatively neglected. The point of this comment is that…

  12. Survival motor neuron protein in motor neurons determines synaptic integrity in spinal muscular atrophy.

    PubMed

    Martinez, Tara L; Kong, Lingling; Wang, Xueyong; Osborne, Melissa A; Crowder, Melissa E; Van Meerbeke, James P; Xu, Xixi; Davis, Crystal; Wooley, Joe; Goldhamer, David J; Lutz, Cathleen M; Rich, Mark M; Sumner, Charlotte J

    2012-06-20

    The inherited motor neuron disease spinal muscular atrophy (SMA) is caused by deficient expression of survival motor neuron (SMN) protein and results in severe muscle weakness. In SMA mice, synaptic dysfunction of both neuromuscular junctions (NMJs) and central sensorimotor synapses precedes motor neuron cell death. To address whether this synaptic dysfunction is due to SMN deficiency in motor neurons, muscle, or both, we generated three lines of conditional SMA mice with tissue-specific increases in SMN expression. All three lines of mice showed increased survival, weights, and improved motor behavior. While increased SMN expression in motor neurons prevented synaptic dysfunction at the NMJ and restored motor neuron somal synapses, increased SMN expression in muscle did not affect synaptic function although it did improve myofiber size. Together these data indicate that both peripheral and central synaptic integrity are dependent on motor neurons in SMA, but SMN may have variable roles in the maintenance of these different synapses. At the NMJ, it functions at the presynaptic terminal in a cell-autonomous fashion, but may be necessary for retrograde trophic signaling to presynaptic inputs onto motor neurons. Importantly, SMN also appears to function in muscle growth and/or maintenance independent of motor neurons. Our data suggest that SMN plays distinct roles in muscle, NMJs, and motor neuron somal synapses and that restored function of SMN at all three sites will be necessary for full recovery of muscle power.

  13. Intrinsic and extrinsic neuromodulation of motor circuits.

    PubMed

    Katz, P S

    1995-12-01

    Neuromodulation of motor circuits by extrinsic inputs provides enormous flexibility in the production of behavior. Recent work has shown that neurons intrinsic to central pattern-generating circuits can evoke neuromodulatory effects in addition to their neurotransmitting actions. Modulatory neurons often elicit a multitude of different effects attributable to actions at different receptors and/or through the release of co-transmitters. Differences in neuromodulation between species can account for differences in behavior. Modulation of neuromodulation may provide an additional level of flexibility to motor circuits.

  14. Motor Priming in Neurorehabilitation

    PubMed Central

    Stoykov, Mary Ellen; Madhavan, Sangeetha

    2014-01-01

    Priming is a type of implicit learning wherein a stimulus prompts a change in behavior. Priming has been long studied in the field of psychology. More recently, rehabilitation researchers have studied motor priming as a possible way to facilitate motor learning. For example, priming of the motor cortex is associated with changes in neuroplasticity that are associated with improvements in motor performance. Of the numerous motor priming paradigms under investigation, only a few are practical for the current clinical environment, and the optimal priming modalities for specific clinical presentations are not known. Accordingly, developing an understanding of the various types of motor priming paradigms and their underlying neural mechanisms is an important step for therapists in neurorehabilitation. Most importantly, an understanding of the methods and their underlying mechanisms is essential for optimizing rehabilitation outcomes. The future of neurorehabilitation is likely to include these priming methods, which are delivered prior to or in conjunction with primary neurorehabilitation therapies. In this Special Interest article we discuss those priming paradigms that are supported by the greatest amount of evidence including: (i) stimulation-based priming, (ii) motor imagery and action observation, (iii) sensory priming, (iv) movement-based priming, and (v) pharmacological priming. PMID:25415551

  15. Influences of motor contexts on the semantic processing of action-related language.

    PubMed

    Yang, Jie

    2014-09-01

    The contribution of the sensory-motor system to the semantic processing of language stimuli is still controversial. To address the issue, the present article focuses on the impact of motor contexts (i.e., comprehenders' motor behaviors, motor-training experiences, and motor expertise) on the semantic processing of action-related language and reviews the relevant behavioral and neuroimaging findings. The existing evidence shows that although motor contexts can influence the semantic processing of action-related concepts, the mechanism of the contextual influences is still far from clear. Future investigations will be needed to clarify (1) whether motor contexts only modulate activity in motor regions, (2) whether the contextual influences are specific to the semantic features of language stimuli, and (3) what factors can determine the facilitatory or inhibitory contextual influences on the semantic processing of action-related language.

  16. Motor Learning Enhances Use-Dependent Plasticity

    PubMed Central

    2017-01-01

    Motor behaviors are shaped not only by current sensory signals but also by the history of recent experiences. For instance, repeated movements toward a particular target bias the subsequent movements toward that target direction. This process, called use-dependent plasticity (UDP), is considered a basic and goal-independent way of forming motor memories. Most studies consider movement history as the critical component that leads to UDP (Classen et al., 1998; Verstynen and Sabes, 2011). However, the effects of learning (i.e., improved performance) on UDP during movement repetition have not been investigated. Here, we used transcranial magnetic stimulation in two experiments to assess plasticity changes occurring in the primary motor cortex after individuals repeated reinforced and nonreinforced actions. The first experiment assessed whether learning a skill task modulates UDP. We found that a group that successfully learned the skill task showed greater UDP than a group that did not accumulate learning, but made comparable repeated actions. The second experiment aimed to understand the role of reinforcement learning in UDP while controlling for reward magnitude and action kinematics. We found that providing subjects with a binary reward without visual feedback of the cursor led to increased UDP effects. Subjects in the group that received comparable reward not associated with their actions maintained the previously induced UDP. Our findings illustrate how reinforcing consistent actions strengthens use-dependent memories and provide insight into operant mechanisms that modulate plastic changes in the motor cortex. SIGNIFICANCE STATEMENT Performing consistent motor actions induces use-dependent plastic changes in the motor cortex. This plasticity reflects one of the basic forms of human motor learning. Past studies assumed that this form of learning is exclusively affected by repetition of actions. However, here we showed that success-based reinforcement signals could

  17. Numerical analysis of wavefront aberration correction using multielectrode electrowetting-based devices.

    PubMed

    Zohrabi, Mo; Cormack, Robert H; Mccullough, Connor; Supekar, Omkar D; Gibson, Emily A; Bright, Victor M; Gopinath, Juliet T

    2017-12-11

    We present numerical simulations of multielectrode electrowetting devices used in a novel optical design to correct wavefront aberration. Our optical system consists of two multielectrode devices, preceded by a single fixed lens. The multielectrode elements function as adaptive optical devices that can be used to correct aberrations inherent in many imaging setups, biological samples, and the atmosphere. We are able to accurately simulate the liquid-liquid interface shape using computational fluid dynamics. Ray tracing analysis of these surfaces shows clear evidence of aberration correction. To demonstrate the strength of our design, we studied three different input aberrations mixtures that include astigmatism, coma, trefoil, and additional higher order aberration terms, with amplitudes as large as one wave at 633 nm.

  18. Texting while driving and other risky motor vehicle behaviors among US high school students.

    PubMed

    Olsen, Emily O'Malley; Shults, Ruth A; Eaton, Danice K

    2013-06-01

    To assess the prevalence of texting/e-mailing while driving (TWD) and association of TWD with other risky motor vehicle (MV) behaviors among US high school students. Data were used from the Centers for Disease Control and Prevention's 2011 national Youth Risk Behavior Survey, which assessed TWD during the 30 days before the survey among 8505 students aged ≥16 years from a nationally representative sample of US high school students. TWD frequency was coded into dichotomous and polychotomous variables. Logistic regression assessed the relationship between TWD and other risky driving behaviors, controlling for age, race/ethnicity, and sex. The prevalence of TWD on ≥1 days during the 30 days before the survey was 44.5% (95% confidence interval: 40.8%-48.2%). Students who engaged in TWD were more likely than their non-TWD counterparts to not always wear their seatbelt (prevalence ratio; 95% confidence interval: 1.16; 1.07-1.26), ride with a driver who had been drinking alcohol (1.74; 1.57-1.93), and drink alcohol and drive (5.33; 4.32-6.59). These other risky MV behaviors were most likely to occur among students who frequently engaged in TWD. Nearly half of US high school students aged ≥16 years report TWD during the past 30 days; these students are more likely to engage in additional risky MV behaviors. This suggests there is a subgroup of students who may place themselves, their passengers, and others on the road at elevated risk for a crash-related injury or fatality by engaging in multiple risky MV behaviors.

  19. Stability of corneal topography and wavefront aberrations in young Singaporeans.

    PubMed

    Zhu, Mingxia; Collins, Michael J; Yeo, Anna C H

    2013-09-01

    The aim was to investigate the differences between and variations across time in corneal topography and ocular wavefront aberrations in young Singaporean myopes and emmetropes. We used a videokeratoscope and wavefront sensor to measure the ocular surface topography and wavefront aberrations of the total-eye optics in the morning, midday and late afternoon on two separate days. Topographic data were used to derive the corneal surface wavefront aberrations. Both the corneal and total wavefronts were analysed up to the fourth radial order of the Zernike polynomial expansion and were centred on the entrance pupil (5.0 mm). The participants included 12 young progressing myopes, 13 young stable myopes and 15 young age-matched emmetropes. For all subjects considered together, there were significant changes in some of the aberrations across the day, such as spherical aberration ( Z(4 0)) and vertical coma ( Z (3 - 1)) (repeated measures analysis of variance, p < 0.05). The magnitude of positive spherical aberration ( Z(4 0)) was significantly lower in the progressing myopic group than in the stable myopic (p = 0.04) and emmetropic (p = 0.02) groups. There were also significant interactions between refractive group and time of day for with and against-the-rule astigmatism ( Z(2 2)). Significantly lower fourth-order root mean square of ocular wavefront aberrations were found in the progressing myopic group compared with the stable myopes and emmetropes (p < 0.01). These differences and variations in the corneal and total aberrations may have significance for our understanding of refractive error development and for clinical applications requiring accurate wavefront measurements. © 2013 The Authors. Clinical and Experimental Optometry © 2013 Optometrists Association Australia.

  20. Chromosomal aberrations in 2000 couples of Indian ethnicity with reproductive failure.

    PubMed

    Gada Saxena, S; Desai, K; Shewale, L; Ranjan, P; Saranath, D

    2012-08-01

    Constitutional chromosomal aberrations contribute to infertility and repeated miscarriage leading to reproductive failure in couples. These aberrations may show no obvious clinical manifestations and remain undetected across multiple generations. However, infertility or recurrent spontaneous pregnancy loss, and/or genotypic/phenotypic aberrations may be manifested in the progeny during gametogenesis. The current study was a retrospective analysis to examine the chromosomal aberrations and prevalence in 2000 couples of Indian ethnicity with reproductive failure. Cytogenetic analysis via conventional G-band karyotyping analysis was carried out on phytohaemagglutinin stimulated peripheral blood lymphocytes, cultured in RPMI1640 medium. The chromosomes were enumerated as per International System for Human Cytogenetic Nomenclature at 500-550 band resolution, and recorded in the screening sheets. Chromosomal aberrations were detected in a total of 110 (2.78%) couples, with structural chromosomal aberrations in 88 cases including reciprocal translocations in 56 cases, Robertsonian translocations in 16 cases, inversions in eight cases, deletions in three cases, derivative chromosomes in five cases and numerical chromosome aberrations in 23 cases. The study emphasizes the importance of cytogenetic work up in both the partners associated with a history of reproductive failure. Genetic counselling with an option of prenatal diagnosis should be offered to couples with chromosomal aberrations. Copyright © 2012 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  1. Dimensions of driving anger and their relationships with aberrant driving.

    PubMed

    Zhang, Tingru; Chan, Alan H S; Zhang, Wei

    2015-08-01

    The purpose of this study was to investigate the relationship between driving anger and aberrant driving behaviours. An internet-based questionnaire survey was administered to a sample of Chinese drivers, with driving anger measured by a 14-item short Driving Anger Scale (DAS) and the aberrant driving behaviours measured by a 23-item Driver Behaviour Questionnaire (DBQ). The results of Confirmatory Factor Analysis demonstrated that the three-factor model (hostile gesture, arrival-blocking and safety-blocking) of the DAS fitted the driving anger data well. The Exploratory Factor Analysis on DBQ data differentiated four types of aberrant driving, viz. emotional violation, error, deliberate violation and maintaining progress violation. For the anger-aberration relation, it was found that only "arrival-blocking" anger was a significant positive predictor for all four types of aberrant driving behaviours. The "safety-blocking" anger revealed a negative impact on deliberate violations, a finding different from previously established positive anger-aberration relation. These results suggest that drivers with different patterns of driving anger would show different behavioural tendencies and as a result intervention strategies may be differentially effective for drivers of different profiles. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Ocular wavefront aberration and refractive error in pre-school children

    NASA Astrophysics Data System (ADS)

    Thapa, Damber; Fleck, Andre; Lakshminarayanan, Vasudevan; Bobier, William R.

    2011-11-01

    Hartmann-Shack images taken from an archived collection of SureSight refractive measurements of pre-school children in Oxford County, Ontario, Canada were retrieved and re-analyzed. Higher-order aberrations were calculated over the age range of 3 to 6 years. These higher-order aberrations were compared with respect to magnitudes of ametropia. Subjects were classified as emmetropic (range -0.5 to + 0.5D), low hyperopic (+ 0.5 to +2D) and high hyperopic (+2D or more) based upon the resulting spherical equivalent. Higher-order aberrations were found to increase with higher levels of hyperopia (p < 0.01). The strongest effect was for children showing more than +2.00D of hyperopia. The correlation coefficients were small in all of the higher-order aberrations; however, they were significant (p < 0.01). These analyses indicate a weak association between refractive error and higher-order aberrations in pre-school children.

  3. Optimizing Feedback Utilization in Motor Skill Training

    DTIC Science & Technology

    1988-02-01

    Abehiorlemphasis. Champaign, IL: Human Kinetics Press. Schmidt, R.A., & White, J.L. (1972). Evidence for an error-detection mechanism in motor skills...motor program. In D.M. Landers & R.W. Christina (Eds.), Psyc g 2 moto behavior d S (Vol 1). Champaign, IL: Human Kinetics Press. Shapiro, D.C. (1978...and sport research. Champaign, IL: Human Kinetics Press. Schmidt, R.A. (in press). Toward a better understanding of motor learning. Theoretical and

  4. Dynamic accommodation with simulated targets blurred with high order aberrations

    PubMed Central

    Gambra, Enrique; Wang, Yinan; Yuan, Jing; Kruger, Philip B.; Marcos, Susana

    2010-01-01

    High order aberrations have been suggested to play a role in determining the direction of accommodation. We have explored the effect of retinal blur induced by high order aberrations on dynamic accommodation by measuring the accommodative response to sinusoidal variations in accommodative demand (1–3 D). The targets were blurred with 0.3 and 1 μm (for a 3-mm pupil) of defocus, coma, trefoil and spherical aberration. Accommodative gain decreased significantly when 1-μm of aberration was induced. We found a strong correlation between the relative accommodative gain (and phase lag) and the contrast degradation imposed on the target at relevant spatial frequencies. PMID:20600230

  5. Comparison of wavefront aberrations under cycloplegic, scotopic and photopic conditions using WaveScan.

    PubMed

    Fan, Rong; He, Tao; Qiu, Yan; Di, Yu-Lan; Xu, Su-yun; Li, Yao-yu

    2012-01-01

    To evaluate the differences of wavefront aberrations under cycloplegic, scotopic and photopic conditions. A total of 174 eyes of 105 patients were measured using the wavefront sensor (WaveScan® 3.62) under different pupil conditions: cycloplegic 8.58 ± 0.54 mm (6.4 mm - 9.5 mm), scotopic 7.53 ± 0.69 mm (5.7 mm - 9.1 mm) and photopic 6.08 ± 1.14 mm (4.1 mm - 8.8 mm). The pupil diameter, standard Zernike coefficients, root mean square of higher-order aberrations and dominant aberrations were compared between cycloplegic and scotopic conditions, and between scotopic and photopic conditions. The pupil diameter was 7.53 ± 0.69 mm under the scotopic condition, which reached the requirement of about 6.5 mm optical zone design in the wavefront-guided surgery and prevented measurement error due to the pupil centroid shift caused by mydriatics. Pharmacological pupil dilation induced increase of standard Zernike coefficients Z(3)(-3), Z(4)(0) and Z(5)(-5). The higher-order aberrations, third-order aberration, fourth-order aberration, fifth-order aberration, sixth-order aberration, and spherical aberration increased statistically significantly, compared to the scotopic condition (P<0.010). When the scotopic condition shifted to the photopic condition, the standard Zernike coefficients Z(4)(0), Z(4)(2), Z(6)(-4), Z(6)(-2), Z(6)(2) decreased and all the higher-order aberrations decreased statistically significantly (P<0.010), demonstrating that accommodative miosis can significantly improve vision under the photopic condition. Under the three conditions, the vertical coma aberration appears the most frequently within the dominant aberrations without significant effect by pupil size variance, and the proportion of spherical aberrations decreased with the decrease of the pupil size. The wavefront aberrations are significantly different under cycloplegic, scotopic and photopic conditions. Using the wavefront sensor (VISX WaveScan) to measure scotopic wavefront aberrations is

  6. Aberrant Salience, Self-Concept Clarity, and Interview-Rated Psychotic-Like Experiences

    PubMed Central

    Cicero, David C.; Docherty, Anna R.; Becker, Theresa M.; Martin, Elizabeth A.; Kerns, John G.

    2014-01-01

    Many social-cognitive models of psychotic-like symptoms posit a role for self-concept and aberrant salience. Previous work has shown that the interaction between aberrant salience and self-concept clarity is associated with self-reported psychotic-like experiences. In the current research with two structured interviews, the interaction between aberrant salience and self-concept clarity was found to be associated withinterview-rated psychotic-like experiences. The interaction was associated withpsychotic-like experiences composite scores, delusional ideation, grandiosity, and perceptual anomalies. In all cases, self-concept clarity was negatively associated with psychotic-like experiences at high levels of aberrant salience, but unassociated with psychotic-like experiences at low levels of aberrant salience. The interaction was specific to positive psychotic-like experiences and not present for negative or disorganized ratings. The interaction was not mediated by self-esteem levels. These results provide further evidence that aberrant salience and self-concept clarity play an important role in the generation of psychotic-like experiences. PMID:25102085

  7. Electrifying the motor engram: effects of tDCS on motor learning and control

    PubMed Central

    de Xivry, Jean-Jacques Orban; Shadmehr, Reza

    2014-01-01

    Learning to control our movements accompanies neuroplasticity of motor areas of the brain. The mechanisms of neuroplasticity are diverse and produce what is referred to as the motor engram, i.e. the neural trace of the motor memory. Transcranial direct current stimulation (tDCS) alters the neural and behavioral correlates of motor learning, but its precise influence on the motor engram is unknown. In this review, we summarize the effects of tDCS on neural activity and suggest a few key principles: 1) firing rates are increased by anodal polarization and decreased by cathodal polarization, 2) anodal polarization strengthens newly formed associations, and 3) polarization modulates the memory of new/preferred firing patterns. With these principles in mind, we review the effects of tDCS on motor control, motor learning, and clinical applications. The increased spontaneous and evoked firing rates may account for the modulation of dexterity in non-learning tasks by tDCS. The facilitation of new association may account for the effect of tDCS on learning in sequence tasks while the ability of tDCS to strengthen memories of new firing patterns may underlie the effect of tDCS on consolidation of skills. We then describe the mechanisms of neuroplasticity of motor cortical areas and how they might be influenced by tDCS. We end with current challenges for the fields of brain stimulation and motor learning. PMID:25200178

  8. Electrifying the motor engram: effects of tDCS on motor learning and control.

    PubMed

    Orban de Xivry, Jean-Jacques; Shadmehr, Reza

    2014-11-01

    Learning to control our movements is accompanied by neuroplasticity of motor areas of the brain. The mechanisms of neuroplasticity are diverse and produce what is referred to as the motor engram, i.e., the neural trace of the motor memory. Transcranial direct current stimulation (tDCS) alters the neural and behavioral correlates of motor learning, but its precise influence on the motor engram is unknown. In this review, we summarize the effects of tDCS on neural activity and suggest a few key principles: (1) Firing rates are increased by anodal polarization and decreased by cathodal polarization, (2) anodal polarization strengthens newly formed associations, and (3) polarization modulates the memory of new/preferred firing patterns. With these principles in mind, we review the effects of tDCS on motor control, motor learning, and clinical applications. The increased spontaneous and evoked firing rates may account for the modulation of dexterity in non-learning tasks by tDCS. The facilitation of new association may account for the effect of tDCS on learning in sequence tasks while the ability of tDCS to strengthen memories of new firing patterns may underlie the effect of tDCS on consolidation of skills. We then describe the mechanisms of neuroplasticity of motor cortical areas and how they might be influenced by tDCS. We end with current challenges for the fields of brain stimulation and motor learning.

  9. Recurrent branchial sinus tract with aberrant extension.

    PubMed

    Barret, J P

    2004-01-01

    Second branchial cysts are the commonest lesions among congenital lateral neck anomalies. Good knowledge of anatomy and embryology are necessary for proper treatment. Surgical treatment involves resection of all branchial remnants, which extend laterally in the neck, medial to the sternocleidomastoid muscle with cranial extension to the pharynx and ipsilateral tonsillar fosa. However, infections and previous surgery can distort anatomy, making the approach to branchial anomalies more difficult. We present a case of a 17-year-old patient who presented with a second branchial tract anomaly with an aberrant extension to the midline and part of the contralateral neck. Previous surgical interventions and chronic infections may have been the primary cause for this aberrant tract. All head and neck surgeons should bear in mind that aberrant presentations may exist when reoperating on chronic branchial cysts fistulas.

  10. Chromosomal aberrations in peripheral lymphocytes of train engine drivers.

    PubMed

    Nordenson, I; Mild, K H; Järventaus, H; Hirvonen, A; Sandström, M; Wilén, J; Blix, N; Norppa, H

    2001-07-01

    Studies of Swedish railway employees have indicated that railroad engine drivers have an increased cancer morbidity and incidence of chronic lymphatic leukemia. The drivers are exposed to relatively high magnetic fields (MF), ranging from a few to over a hundred microT. Although the possible genotoxic potential of MF is unclear, some earlier studies have indicated that occupational exposure to MF may increase chromosome aberrations in blood lymphocytes. Since an increased level of chromosomal aberrations has been suggested to predict elevated cancer risk, we performed a cytogenetic analysis on cultured (48 h) peripheral lymphocytes of Swedish train engine drivers. A pilot study of 18 engine drivers indicated a significant difference in the frequency of cells with chromosomal aberrations (gaps included or excluded) in comparison with seven concurrent referents (train dispatchers) and a control group of 16 office workers. The engine drivers had about four times higher frequency of cells with chromosome-type aberrations (excluding gaps) than the office workers (P < 0.01) and the dispatchers (P < 0.05). Seventy-eight percent of the engine drivers showed at least one cell per 100 with chromosome-type aberrations compared with 29% among the dispatchers and 31% among the office workers. In a follow-up study, another 30 engine drivers showed an increase (P < 0.05) in the frequency of cells with chromosome-type aberrations (gaps excluded) as compared with 30 referent policemen. Sixty percent of the engine drivers had one or more cells (per 100 cells) with chromosome-type aberrations compared with 30% among the policemen. In conclusion, the results of the two studies support the hypothesis that exposure to MF at mean intensities of 2-15 microT can induce chromosomal damage. Copyright 2001 Wiley-Liss, Inc.

  11. In vivo longitudinal chromatic aberration of pseudophakic eyes.

    PubMed

    Siedlecki, Damian; Jóźwik, Agnieszka; Zając, Marek; Hill-Bator, Aneta; Turno-Kręcicka, Anna

    2014-02-01

    To present the results of longitudinal chromatic aberration measurements on two groups of pseudophakic eyes in comparison to healthy eyes. The longitudinal chromatic aberration of the eye, defined as chromatic difference of refraction with disabled accommodation, was measured with the use of a visual refractometer with a custom-designed target illuminator consisting of a narrow-band RGB diode (blue λb = 470 ± 15 nm; green λg = 525 ± 18 nm; red λr = 660 ± 10 nm). The measurements were performed on nine eyes implanted with AcrySof IQ SN60WF, 14 eyes implanted with AcrySof SA60AT, and 10 phakic eyes under cycloplegia. The mean values of the longitudinal chromatic aberration between 470 and 660 nm for the control group was 1.12 ± 0.14 D. For SA60AT group, it was 1.45 ± 0.42 D whereas for SN60WF it was 1.17 ± 0.52 D. The statistical test showed significant difference between SA60AT and the control group (p < 0.05) and no significant difference between SN60WF and the control groups (p = 0.64). The study showed that the longitudinal chromatic aberration in vivo can be easily and reliably estimated with an adapted visual refractometer. The two groups of pseudophakic eyes measured in this study showed different values of chromatic aberration. Its magnitude for SA60AT group was significantly larger than for the control group whereas for SN60WF the difference was not significant. The optical material used for intraocular lens design may have significant influence on the magnitude of the chromatic aberration of the pseudophakic eye, and therefore on its optical and visual performance in polychromatic light.

  12. Modified Matching Ronchi Test to Visualize Lens Aberrations

    ERIC Educational Resources Information Center

    Hassani, Kh; Ziafi, H. Hooshmand

    2011-01-01

    We introduce a modification to the matching Ronchi test to visualize lens aberrations with simple and inexpensive equipment available in educational optics labs. This method can help instructors and students to observe and estimate lens aberrations in real time. It is also a semi-quantitative tool for primary tests in research labs. In this work…

  13. Sextupole system for the correction of spherical aberration

    DOEpatents

    Crewe, A.V.; Kopf, D.A.

    In an electron beam device in which an electron beam is developed and then focused by a lens to a particular spot, there is provided a means for eliminating spherical aberration. A sextupole electromagnetic lens is positioned between two focusing lenses. The interaction of the sextupole with the beam compensates for spherical aberration. (GHT)

  14. Brillouin micro-spectroscopy through aberrations via sensorless adaptive optics

    NASA Astrophysics Data System (ADS)

    Edrei, Eitan; Scarcelli, Giuliano

    2018-04-01

    Brillouin spectroscopy is a powerful optical technique for non-contact viscoelastic characterizations which has recently found applications in three-dimensional mapping of biological samples. Brillouin spectroscopy performances are rapidly degraded by optical aberrations and have therefore been limited to homogenous transparent samples. In this work, we developed an adaptive optics (AO) configuration designed for Brillouin scattering spectroscopy to engineer the incident wavefront and correct for aberrations. Our configuration does not require direct wavefront sensing and the injection of a "guide-star"; hence, it can be implemented without the need for sample pre-treatment. We used our AO-Brillouin spectrometer in aberrated phantoms and biological samples and obtained improved precision and resolution of Brillouin spectral analysis; we demonstrated 2.5-fold enhancement in Brillouin signal strength and 1.4-fold improvement in axial resolution because of the correction of optical aberrations.

  15. A model of distributed phase aberration for deblurring phase estimated from scattering.

    PubMed

    Tillett, Jason C; Astheimer, Jeffrey P; Waag, Robert C

    2010-01-01

    Correction of aberration in ultrasound imaging uses the response of a point reflector or its equivalent to characterize the aberration. Because a point reflector is usually unavailable, its equivalent is obtained using statistical methods, such as processing reflections from multiple focal regions in a random medium. However, the validity of methods that use reflections from multiple points is limited to isoplanatic patches for which the aberration is essentially the same. In this study, aberration is modeled by an offset phase screen to relax the isoplanatic restriction. Methods are developed to determine the depth and phase of the screen and to use the model for compensation of aberration as the beam is steered. Use of the model to enhance the performance of the noted statistical estimation procedure is also described. Experimental results obtained with tissue-mimicking phantoms that implement different models and produce different amounts of aberration are presented to show the efficacy of these methods. The improvement in b-scan resolution realized with the model is illustrated. The results show that the isoplanatic patch assumption for estimation of aberration can be relaxed and that propagation-path characteristics and aberration estimation are closely related.

  16. Development of uncoupling between D1- and D2-mediated motor behavior in rats depleted of dopamine as neonates.

    PubMed

    Byrnes, E M; Bruno, J P

    1994-09-01

    The D1- and D2-mediation of stimulated motor behavior was studied in pups (Days 10-11) and weanlings (Days 20-21) that had been depleted of dopamine (DA) on postnatal Day 3. Administration of the D1-like agonist SKF 38393 (30.0 mg/kg) or the D2-like agonist quinpirole (3.0 mg/kg) increased the incidence of sniffing and locomotion in intact and DA-depleted animals tested at either age. However, the ability of selective DA antagonists to reduce these stimulated responses interacted with both the depletion and the age at the time of testing. When tested as pups, both the D1 antagonist SCH 23390 (0.2 or 0.4 mg/kg) and the D2 antagonist clebopride (10.0 mg/kg) suppressed the behaviors induced by either class of DA agonist. When tested as weanlings, intact animals exhibited the profile of pups (i.e., either antagonist blocked each agonist). In DA-depleted weanlings, however, only the D1 antagonist blocked the D1 agonist-induced responses and only the D2 antagonist blocked the D2 agonist-induced responses. These data demonstrate that the interactions between D1 and D2 receptors in the expression of stimulated motor behaviors are altered following DA depletions in neonates. Moreover, this change in receptor function occurs sometime between 7 and 13 days after the DA depletion.

  17. Refractive Changes Induced by Spherical Aberration in Laser Correction Procedures: An Adaptive Optics Study.

    PubMed

    Amigó, Alfredo; Martinez-Sorribes, Paula; Recuerda, Margarita

    2017-07-01

    To study the effect on vision of induced negative and positive spherical aberration within the range of laser vision correction procedures. In 10 eyes (mean age: 35.8 years) under cyclopegic conditions, spherical aberration values from -0.75 to +0.75 µm in 0.25-µm steps were induced by an adaptive optics system. Astigmatism and spherical refraction were corrected, whereas the other natural aberrations remained untouched. Visual acuity, depth of focus defined as the interval of vision for which the target was still perceived acceptable, contrast sensitivity, and change in spherical refraction associated with the variation in pupil diameter from 6 to 2.5 mm were measured. A refractive change of 1.60 D/µm of induced spherical aberration was obtained. Emmetropic eyes became myopic when positive spherical aberration was induced and hyperopic when negative spherical aberration was induced (R 2 = 81%). There were weak correlations between spherical aberration and visual acuity or depth of focus (R 2 = 2% and 3%, respectively). Contrast sensitivity worsened with the increment of spherical aberration (R 2 = 59%). When pupil size decreased, emmetropic eyes became hyperopic when preexisting spherical aberration was positive and myopic when spherical aberration was negative, with an average refractive change of 0.60 D/µm of spherical aberration (R 2 = 54%). An inverse linear correlation exists between the refractive state of the eye and spherical aberration induced within the range of laser vision correction. Small values of spherical aberration do not worsen visual acuity or depth of focus, but positive spherical aberration may induce night myopia. In addition, the changes in spherical refraction when the pupil constricts may worsen near vision when positive spherical aberration is induced or improve it when spherical aberration is negative. [J Refract Surg. 2017;33(7):470-474.]. Copyright 2017, SLACK Incorporated.

  18. Surgical and healing changes to ocular aberrations following refractive surgery

    NASA Astrophysics Data System (ADS)

    Straub, Jochen; Schwiegerling, Jim

    2003-07-01

    Purpose: To measure ocular aberrations before and at several time periods after LASIK surgery to determine the change to the aberration structure of the eye. Methods: A Shack-Hartmann wavefront sensor was used to measure 88 LASIK patients pre-operatively and at 1 week and 12 months following surgery. Reconstructed wavefront errors are compared to look at induced differences. Manifest refraction was measured at 1 week, 1 month, 3 months, 6 months and 12 months following surgery. Sphere, cylinder, spherical aberration, and pupil diameter are analyzed. Results: A dramatic elevation in spherical aberration is seen following surgery. This elevation appears almost immediately and remains for the duration of the study. A temporary increase in pupil size is seen following surgery. Conclusions: LASIK surgery dramatically reduces defocus and astigmatism in the eye, but simultaneously increases spherical aberration levels. This increase occurs at the time of surgery and is not an effect of the healing response.

  19. Correlation between Post-LASIK Starburst Symptom and Ocular Wavefront Aberrations

    NASA Astrophysics Data System (ADS)

    Liu, Yong-Ji; Mu, Guo-Guang; Wang, Zhao-Qi; Wang-Yan

    2006-06-01

    Monochromatic aberrations in post laser in-situ keratomileusis (LASIK) eyes are measured. The data are categorized into reference group and starburst group according to the visual symptoms. Statistic analysis has been made to find the correlation between the ocular wavefront aberrations and the starburst symptom. The rms aberrations of the 3rd and 4th orders for the starburst group are significantly larger than those for the reference group. The starburst symptom shows a strong correlation with vertical coma, total coma, spherical aberrations. For 3-mm pupil size and 5.8-mm pupil size, the modulation transfer function (MTF) of the starburst group are lower than those of the reference group, but their visual acuities are close. MTF and PSF analyses are made for two groups, and the results are consistent with the statistical analysis, which means the difference between the two groups is mainly due to the third- and fourth-order Zernike aberrations.

  20. Laryngeal Motor Cortex and Control of Speech in Humans

    PubMed Central

    Simonyan, Kristina; Horwitz, Barry

    2011-01-01

    Speech production is one of the most complex and rapid motor behaviors and involves a precise coordination of over 100 laryngeal, orofacial and respiratory muscles. Yet, we lack a complete understanding of laryngeal motor cortical control during production of speech and other voluntary laryngeal behaviors. In recent years, a number of studies have confirmed the laryngeal motor cortical representation in humans and provided some information about its interactions with other cortical and subcortical regions that are principally involved in vocal motor control of speech production. In this review, we discuss the organization of the peripheral and central laryngeal control based on neuroimaging and electrical stimulation studies in humans and neuroanatomical tracing studies in non-human primates. We hypothesize that the location of the laryngeal motor cortex in the primary motor cortex and its direct connections with the brainstem laryngeal motoneurons in humans, as oppose to its location in the premotor cortex with only indirect connections to the laryngeal motoneurons in non-human primates, may represent one of the major evolutionary developments in humans towards the ability to speak and vocalize voluntarily. PMID:21362688

  1. In Vivo Neuromechanics: Decoding Causal Motor Neuron Behavior with Resulting Musculoskeletal Function.

    PubMed

    Sartori, Massimo; Yavuz, Utku Ş; Farina, Dario

    2017-10-18

    Human motor function emerges from the interaction between the neuromuscular and the musculoskeletal systems. Despite the knowledge of the mechanisms underlying neural and mechanical functions, there is no relevant understanding of the neuro-mechanical interplay in the neuro-musculo-skeletal system. This currently represents the major challenge to the understanding of human movement. We address this challenge by proposing a paradigm for investigating spinal motor neuron contribution to skeletal joint mechanical function in the intact human in vivo. We employ multi-muscle spatial sampling and deconvolution of high-density fiber electrical activity to decode accurate α-motor neuron discharges across five lumbosacral segments in the human spinal cord. We use complete α-motor neuron discharge series to drive forward subject-specific models of the musculoskeletal system in open-loop with no corrective feedback. We perform validation tests where mechanical moments are estimated with no knowledge of reference data over unseen conditions. This enables accurate blinded estimation of ankle function purely from motor neuron information. Remarkably, this enables observing causal associations between spinal motor neuron activity and joint moment control. We provide a new class of neural data-driven musculoskeletal modeling formulations for bridging between movement neural and mechanical levels in vivo with implications for understanding motor physiology, pathology, and recovery.

  2. Wavefront aberration changes caused by a gradient of increasing accommodation stimuli

    PubMed Central

    Zhou, X-Y; Wang, L; Zhou, X-T; Yu, Z-Q

    2015-01-01

    Purpose The aim of this study was to investigate the wavefront aberration changes in human eyes caused by a gradient of increasing accommodation stimuli. Design This is a prospective, single-site study. Methods Healthy volunteers (n=22) aged 18–28 years whose refraction states were emmetropia or mild myopia, with astigmatism <1 diopter (D), were included in this study. After dilating the right pupil with 0.5% phenylephrine drops, the wavefront aberration of the right eye was measured continuously either without or with 1, 2, 3, 4, 5, or 6D accommodation stimuli (WFA1000B psychophysical aberrometer). The root mean square (RMS) values of the total wavefront aberrations, higher-order aberrations, and 35 individual Zernike aberrations under different accommodation stimuli were calculated and compared. Results The average induced accommodations using 1, 2, 3, 4, 5, or 6D accommodation stimuli were 0.848, 1.626, 2.375, 3.249, 4.181, or 5.085 D, respectively. The RMS of total wavefront aberrations, as well as higher-order aberrations, showed no significant effects with 1–3 D accommodation stimuli, but increased significantly under 4, 5, and 6 D accommodation stimuli compared with relaxed accommodation. Zernike coefficients of significantly decreased with increasing levels of accommodation. Conclusion Higher-order wavefront aberrations in human eyes changed with increased accommodation. These results are consistent with Schachar's accommodation theory. PMID:25341432

  3. Motor, mental and behavioral developments in infancy are associated with fatty acid pattern in breast milk and plasma of premature infants.

    PubMed

    Sabel, K-G; Strandvik, B; Petzold, M; Lundqvist-Persson, C

    2012-04-01

    The objective of this study was to investigate any association between infants' early development and PUFA concentrations in early breast milk and infants' plasma phospholipids at 44 weeks gestational age. Fifty-one premature infants were included. The quality of general movement was assessed at 3 months, and motor, mental and behavioral development at 3, 6, 10 and 18 months corrected age using Bayley's Scales of Infant Development (BSID-II). Linoleic acid, the major n-6/n-3 FA ratios, Mead acid and the EFA deficiency index in early breast milk were negatively associated with development up to 18 months of age. DHA and AA, respectively, in infants' plasma phospholipids was positively, but the AA/DHA ratio negatively, associated with development from 6 to 18 months of age. Our data suggest that the commonly found high n-6 concentration in breast milk is associated with less favorable motor, mental and behavioral development up to 18 months of age. Copyright © 2012. Published by Elsevier Ltd.

  4. Two is better than one: Physical interactions improve motor performance in humans

    NASA Astrophysics Data System (ADS)

    Ganesh, G.; Takagi, A.; Osu, R.; Yoshioka, T.; Kawato, M.; Burdet, E.

    2014-01-01

    How do physical interactions with others change our own motor behavior? Utilizing a novel motor learning paradigm in which the hands of two - individuals are physically connected without their conscious awareness, we investigated how the interaction forces from a partner adapt the motor behavior in physically interacting humans. We observed the motor adaptations during physical interactions to be mutually beneficial such that both the worse and better of the interacting partners improve motor performance during and after interactive practice. We show that these benefits cannot be explained by multi-sensory integration by an individual, but require physical interaction with a reactive partner. Furthermore, the benefits are determined by both the interacting partner's performance and similarity of the partner's behavior to one's own. Our results demonstrate the fundamental neural processes underlying human physical interactions and suggest advantages of interactive paradigms for sport-training and physical rehabilitation.

  5. Voltage directive drive with claw pole motor and control without rotor position indicator

    NASA Astrophysics Data System (ADS)

    Stroenisch, Volker Ewald

    Design and testing of a voltage directive drive for synchronous variable speed claw pole motor and control without rotor position indicator is described. Economic analysis of the designed regulation is performed. Computations of stationary and dynamic behavior are given and experimental operational behavior is determined. The motors can be used for electric transportation vehicles, diesel motors, and electric railway engines.

  6. Motor Experience Reprograms Development of a Genetically-Altered Bilateral Corticospinal Motor Circuit.

    PubMed

    Serradj, Najet; Martin, John H

    Evidence suggests that motor experience plays a role in shaping development of the corticospinal system and voluntary motor control, which is a key motor function of the system. Here we used a mouse model with conditional forebrain deletion of the gene for EphA4 (Emx1-Cre:EphA4tm2Kldr), which regulates development of the laterality of corticospinal tract (CST). We combined study of Emx1-Cre:EphA4tm2Kldr with unilateral forelimb constraint during development to expand our understanding of experience-dependent CST development from both basic and translational perspectives. This mouse develops dense ipsilateral CST projections, a bilateral motor cortex motor representation, and bilateral motor phenotypes. Together these phenotypes can be used as readouts of corticospinal system organization and function and the changes brought about by experience. The Emx1-Cre:EphA4tm2Kldr mouse shares features with the common developmental disorder cerebral palsy: bilateral voluntary motor impairments and bilateral CST miswiring. Emx1-Cre:EphA4tm2Kldr mice with typical motor experiences during development display the bilateral phenotype of "mirror" reaching, because of a strongly bilateral motor cortex motor representation and a bilateral CST. By contrast, Emx1-Cre:EphA4tm2Kldr mice that experienced unilateral forelimb constraint from P1 to P30 and tested at maturity had a more contralateral motor cortex motor representation in each hemisphere; more lateralized CST projections; and substantially more lateralized/independent reaching movements. Changes in CST organization and function in this model can be explained by reduced synaptic competition of the CST from the side without developmental forelimb motor experiences. Using this model we show that unilateral constraint largely abrogated the effects of the genetic mutation on CST projections and thus demonstrates how robust and persistent experience-dependent development can be for the establishment of corticospinal system

  7. Iterative method for in situ measurement of lens aberrations in lithographic tools using CTC-based quadratic aberration model.

    PubMed

    Liu, Shiyuan; Xu, Shuang; Wu, Xiaofei; Liu, Wei

    2012-06-18

    This paper proposes an iterative method for in situ lens aberration measurement in lithographic tools based on a quadratic aberration model (QAM) that is a natural extension of the linear model formed by taking into account interactions among individual Zernike coefficients. By introducing a generalized operator named cross triple correlation (CTC), the quadratic model can be calculated very quickly and accurately with the help of fast Fourier transform (FFT). The Zernike coefficients up to the 37th order or even higher are determined by solving an inverse problem through an iterative procedure from several through-focus aerial images of a specially designed mask pattern. The simulation work has validated the theoretical derivation and confirms that such a method is simple to implement and yields a superior quality of wavefront estimate, particularly for the case when the aberrations are relatively large. It is fully expected that this method will provide a useful practical means for the in-line monitoring of the imaging quality of lithographic tools.

  8. An aberrant carotid artery in the temporal bone with fatal complication.

    PubMed

    Kimura, Yurika; Makino, Nao; Kobayashi, Hitome; Kitamura, Ken

    2016-06-01

    We report the case of an 84-year-old female presenting with an aberrant ICA with cerebral air embolization caused by Eustachian tube air inflation (ETAI). High pressure of air inflation developed because of an aberrant ICA blocking the tympanic orifice of the Eustachian tube, with release of the high-pressure air into the aberrant ICA. It must be kept in mind that complications may occur not only during transtympanic treatment, but also in any treatment, such as ETAI, in aberrant ICA cases. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  9. Lesion Generation Through Ribs Using Histotripsy Therapy Without Aberration Correction

    PubMed Central

    Kim, Yohan; Wang, Tzu-Yin; Xu, Zhen; Cain, Charles A.

    2012-01-01

    This study investigates the feasibility of using high-intensity pulsed therapeutic ultrasound, or histotripsy, to non-invasively generate lesions through the ribs. Histotripsy therapy mechanically ablates tissue through the generation of a cavitation bubble cloud, which occurs when the focal pressure exceeds a certain threshold. We hypothesize that histotripsy can generate precise lesions through the ribs without aberration correction if the main lobe retains its shape and exceeds the cavitation initiation threshold and the secondary lobes remain below the threshold. To test this hypothesis, a 750-kHz focused transducer was used to generate lesions in tissue-mimicking phantoms with and without the presence of rib aberrators. In all cases, 8000 pulses with 16 to 18 MPa peak rarefactional pressure at a repetition frequency of 100 Hz were applied without aberration correction. Despite the high secondary lobes introduced by the aberrators, high-speed imaging showed that bubble clouds were generated exclusively at the focus, resulting in well-confined lesions with comparable dimensions. Collateral damage from secondary lobes was negligible, caused by single bubbles that failed to form a cloud. These results support our hypothesis, suggesting that histotripsy has a high tolerance for aberrated fields and can generate confined focal lesions through rib obstacles without aberration correction. PMID:22083767

  10. Lesion generation through ribs using histotripsy therapy without aberration correction.

    PubMed

    Kim, Yohan; Wang, Tzu-Yin; Xu, Zhen; Cain, Charles A

    2011-11-01

    This study investigates the feasibility of using high-intensity pulsed therapeutic ultrasound, or histotripsy, to non-invasively generate lesions through the ribs. Histotripsy therapy mechanically ablates tissue through the generation of a cavitation bubble cloud, which occurs when the focal pressure exceeds a certain threshold. We hypothesize that histotripsy can generate precise lesions through the ribs without aberration correction if the main lobe retains its shape and exceeds the cavitation initiation threshold and the secondary lobes remain below the threshold. To test this hypothesis, a 750-kHz focused transducer was used to generate lesions in tissue-mimicking phantoms with and without the presence of rib aberrators. In all cases, 8000 pulses with 16 to 18 MPa peak rarefactional pressure at a repetition frequency of 100 Hz were applied without aberration correction. Despite the high secondary lobes introduced by the aberrators, high-speed imaging showed that bubble clouds were generated exclusively at the focus, resulting in well-confined lesions with comparable dimensions. Collateral damage from secondary lobes was negligible, caused by single bubbles that failed to form a cloud. These results support our hypothesis, suggesting that histotripsy has a high tolerance for aberrated fields and can generate confined focal lesions through rib obstacles without aberration correction.

  11. Induction of chromosome aberrations in human cells by charged particles

    NASA Technical Reports Server (NTRS)

    Wu, H.; Durante, M.; George, K.; Yang, T. C.

    1997-01-01

    Chromosome aberrations induced by high-energy charged particles in normal human lymphocytes and human fibroblasts have been investigated. The charged particles included 250 MeV/nucleon protons, 290 MeV/nucleon carbon ions and 1 GeV/nucleon iron ions. The energies of the charged particles were higher than in most of the studies reported in the literature. Lymphocytes were stimulated to grow immediately after irradiation, while fibroblasts were incubated at 37 degrees C for 24 h for repair. Chromosomes were collected at the first mitosis after irradiation and chromosome aberrations were scored using the fluorescence in situ hybridization (FISH) technique with a whole-chromosome 4 probe. Chromosome aberrations were classified as reciprocal exchanges, incomplete exchanges, deletions and complex exchanges. The relative biological effectiveness (RBE) for each type of aberration was calculated by dividing a dose of 4 Gy by the dose of the charged particles producing the same effect as 4 Gy of gamma rays. Results of this study showed that complex aberrations have the highest RBE for radiation of high linear energy transfer (LET) for human lymphocytes, but for fibroblasts, the greatest effect was for incomplete exchanges. For both lymphocytes and fibroblasts, iron ions induced a similar fraction of aberrant cells.

  12. Structural centrosome aberrations sensitize polarized epithelia to basal cell extrusion.

    PubMed

    Ganier, Olivier; Schnerch, Dominik; Nigg, Erich A

    2018-06-01

    Centrosome aberrations disrupt tissue architecture and may confer invasive properties to cancer cells. Here we show that structural centrosome aberrations, induced by overexpression of either Ninein-like protein (NLP) or CEP131/AZI1, sensitize polarized mammalian epithelia to basal cell extrusion. While unperturbed epithelia typically dispose of damaged cells through apical dissemination into luminal cavities, certain oncogenic mutations cause a switch in directionality towards basal cell extrusion, raising the potential for metastatic cell dissemination. Here we report that NLP-induced centrosome aberrations trigger the preferential extrusion of damaged cells towards the basal surface of epithelial monolayers. This switch in directionality from apical to basal dissemination coincides with a profound reorganization of the microtubule cytoskeleton, which in turn prevents the contractile ring repositioning that is required to support extrusion towards the apical surface. While the basal extrusion of cells harbouring NLP-induced centrosome aberrations requires exogenously induced cell damage, structural centrosome aberrations induced by excess CEP131 trigger the spontaneous dissemination of dying cells towards the basal surface from MDCK cysts. Thus, similar to oncogenic mutations, structural centrosome aberrations can favour basal extrusion of damaged cells from polarized epithelia. Assuming that additional mutations may promote cell survival, this process could sensitize epithelia to disseminate potentially metastatic cells. © 2018 The Authors.

  13. Emerging treatments for the behavioral and psychological symptoms of dementia.

    PubMed

    Anand, Abhinav; Khurana, Puneet; Chawla, Jasneet; Sharma, Neha; Khurana, Navneet

    2017-09-15

    Dementia is referred to a loss of memory and decline in other mental abilities at levels critical enough to hinder performance of daily activities. It can be of several types, depending on the underlying pathophysiology. The behavioral and psychological symptoms of dementia (BPSD) are various, but the most clinically significant are depression, apathy, and anxiety. Other BPSD include agitation, aberrant motor behavior, elation, hallucinations, and alterations in sleep and appetite. About 90% of sufferers of dementia are affected by BPSD during the course of the illness. These symptoms occur in demented patients irrespective of the dementia subtype. However, there has not been significant development in the areas of disease-modifying pharmacotherapeutics for dementia. Therefore, tackling BPSD has emerged as a research avenue in the recent past. Existing antidepressants, antipsychotics, and cholinergic agents have been extensively used in the treatment of BPSD, independently and in different combinations. However, these agents have not successful in completely alleviating such symptoms. Research in this field is going on globally, but it is still limited by various factors. There is a strong need to develop new entities and test them clinically. This review focuses on emerging treatments for the management of clinically significant BPSD.

  14. Ocular wavefront aberrations in patients with macular diseases

    PubMed Central

    Bessho, Kenichiro; Bartsch, Dirk-Uwe G.; Gomez, Laura; Cheng, Lingyun; Koh, Hyoung Jun; Freeman, William R.

    2009-01-01

    Background There have been reports that by compensating for the ocular aberrations using adaptive optical systems it may be possible to improve the resolution of clinical retinal imaging systems beyond what is now possible. In order to develop such system to observe eyes with retinal disease, understanding of the ocular wavefront aberrations in individuals with retinal disease is required. Methods 82 eyes of 66 patients with macular disease (epiretinal membrane, macular edema, macular hole etc.) and 85 eyes of 51 patients without retinal disease were studied. Using a ray-tracing wavefront device, each eye was scanned at both small and large pupil apertures and Zernike coefficients up to 6th order were acquired. Results In phakic eyes, 3rd order root mean square errors (RMS) in macular disease group were statistically greater than control, an average of 12% for 5mm and 31% for 3mm scan diameters (p<0.021). In pseudophakic eyes, there also was an elevation of 3rd order RMS, on average 57% for 5mm and 51% for 3mm scan diameters (p<0.031). Conclusion Higher order wavefront aberrations in eyes with macular disease were greater than in control eyes without disease. Our study suggests that such aberrations may result from irregular or multiple reflecting retinal surfaces. Modifications in wavefront sensor technology will be needed to accurately determine wavefront aberration and allow correction using adaptive optics in eyes with macular irregularities. PMID:19574950

  15. Loss of nuclear TDP-43 in amyotrophic lateral sclerosis (ALS) causes altered expression of splicing machinery and widespread dysregulation of RNA splicing in motor neurones.

    PubMed

    Highley, J Robin; Kirby, Janine; Jansweijer, Joeri A; Webb, Philip S; Hewamadduma, Channa A; Heath, Paul R; Higginbottom, Adrian; Raman, Rohini; Ferraiuolo, Laura; Cooper-Knock, Johnathan; McDermott, Christopher J; Wharton, Stephen B; Shaw, Pamela J; Ince, Paul G

    2014-10-01

    Loss of nuclear TDP-43 characterizes sporadic and most familial forms of amyotrophic lateral sclerosis (ALS). TDP-43 (encoded by TARDBP) has multiple roles in RNA processing. We aimed to determine whether (1) RNA splicing dysregulation is present in lower motor neurones in ALS and in a motor neurone-like cell model; and (2) TARDBP mutations (mtTARDBP) are associated with aberrant RNA splicing using patient-derived fibroblasts. Affymetrix exon arrays were used to study mRNA expression and splicing in lower motor neurones obtained by laser capture microdissection of autopsy tissue from individuals with sporadic ALS and TDP-43 proteinopathy. Findings were confirmed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and in NSC34 motor neuronal cells following shRNA-mediated TDP-43 depletion. Exon arrays and immunohistochemistry were used to study mRNA splicing and TDP-43 expression in fibroblasts from patients with mtTARDBP-associated, sporadic and mutant SOD1-associated ALS. We found altered expression of spliceosome components in motor neurones and widespread aberrations of mRNA splicing that specifically affected genes involved in ribonucleotide binding. This was confirmed in TDP-43-depleted NSC34 cells. Fibroblasts with mtTARDBP showed loss of nuclear TDP-43 protein and demonstrated similar changes in splicing and gene expression, which were not present in fibroblasts from patients with sporadic or SOD1-related ALS. Loss of nuclear TDP-43 is associated with RNA processing abnormalities in ALS motor neurones, patient-derived cells with mtTARDBP, and following artificial TDP-43 depletion, suggesting that splicing dysregulation directly contributes to disease pathogenesis. Key functional pathways affected include those central to RNA metabolism. © 2014 British Neuropathological Society.

  16. Interocular high-order corneal wavefront aberration symmetry

    NASA Astrophysics Data System (ADS)

    Lombardo, Marco; Lombardo, Giuseppe; Serrao, Sebastiano

    2006-04-01

    The interocular symmetry of the high-order corneal wavefront aberration (WA) in a population of myopic eyes was analyzed before and after photorefractive keratectomy (PRK). The preoperative and one-year postoperative corneal aberration data (from third to seventh Zernike orders) for 4- and 7-mm pupils from right and left eyes were averaged after correcting for the effects of enantiomorphism to test for mirror symmetry. Also, the mean corneal point-spread function (PSF) for right and left eyes was calculated. Preoperatively, a moderate and high degree of correlation in the high-order corneal WA between eyes was found for 4- and 7-mm pupils, respectively. Myopic PRK did not significantly change the interocular symmetry of corneal high-order aberrations. No discernible differences in the orientation PSF between eyes were observed one year after surgery in comparison with the preoperative state over the two analyzed pupils.

  17. Lethality of radiation-induced chromosome aberrations in human tumour cell lines with different radiosensitivities.

    PubMed

    Coco-Martin, J M; Ottenheim, C P; Bartelink, H; Begg, A C

    1996-03-01

    In order to find an explanation for the eventual disappearance of all chromosome aberrations in two radiosensitive human tumour cell lines, the type and stability of different aberration types was investigated in more detail. To classify the aberrations into unstable and stable types, three-colour fluorescence in situ hybridization was performed, including a whole-chromosome probe, a pancentromere probe, and a stain for total DNA. This technique enables the appropriate classification of the aberrations principally by the presence (stable) or not (unstable) of a single centromere per chromosome. Unstable-type aberrations were found to disappear within 7 days (several divisions) in the two radiosensitive and the two radioresistant tumour lines investigated. Stable-type aberrations were found to remain at an approximately constant level over the duration of the experiment (14 days; 8-10 divisions) in the two radioresistant lines. In contrast, the majority of these stable-type aberrations had disappeared by 14 days in the two radiosensitive lines. The previous findings of disappearance of total aberrations in radiosensitive cells was therefore not due to a reduced induction of stable-type aberrations, but the complete disappearance of cells with this aberration type. These results could not be explained by differences in apoptosis or G1 blocks. Two possible explanations for these unexpected findings involve non-random induction of unstable-type aberrations, or lethality of stable-type aberrations. The results suggest caution in the use of stable-type aberration numbers as a predictor for radiosensitivity.

  18. The aberration characteristics in a misaligned three-mirror anastigmatic (TMA) system

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Wu, Fan; Ye, Yutang

    2016-09-01

    To realize the efficient alignment of the TMA system, the aberrations in a misaligned TMA system had been analyzed theoretically in this paper. Firstly, based on the nodal aberration theory (NAT), the aberration types and characteristics in the misaligned TMA system had been concluded; Secondly, a simulation validation had been carried out to testify the analysis results, the simulation results validates the aberration characteristics; Finally, the alignment procedures were determined according to the aberration characteristics: adjust the axial spacing of the mirrors in terms of Z9 in the center field of TMA system first; and then, adjust the decenters and tilts of the mirrors in terms of Z5 - Z8 in the edge field of TMA system. This method is helpful for the alignment of the TMA telescope.

  19. Inactivation of Pde8b enhances memory, motor performance, and protects against age-induced motor coordination decay

    PubMed Central

    Tsai, Li-Chun Lisa; Chan, Guy Chiu-Kai; Nangle, Shannon N.; Shimizu-Albergine, Masami; Jones, Graham; Storm, Daniel R.; Beavo, Joseph A.; Zweifel, Larry S.

    2012-01-01

    Phosphodiesterases (PDEs) are critical regulatory enzymes in cyclic nucleotide signaling. PDEs have diverse expression patterns within the central nervous system (CNS), show differing affinities for cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), and regulate a vast array of behaviors. Here, we investigated the expression profile of the PDE8 gene family members Pde8a and Pde8b in the mouse brain. We find that Pde8a expression is largely absent in the CNS; by contrast, Pde8b is expressed in select regions of the hippocampus, ventral striatum, and cerebellum. Behavioral analysis of mice with Pde8b gene inactivation (PDE8B KO) demonstrate an enhancement in contextual fear, spatial memory, performance in an appetitive instrumental conditioning task, motor-coordination, and have an attenuation of age-induced motor coordination decline. In addition to improvements observed in select behaviors, we find basal anxiety levels to be increased in PDE8B KO mice. These findings indicate that selective antagonism of PDE8B may be an attractive target for enhancement of cognitive and motor functions; however, possible alterations in affective state will need to be weighed against potential therapeutic value. PMID:22925203

  20. Corneal Aberrations in Former Preterm Infants: Results From The Wiesbaden Prematurity Study.

    PubMed

    Fieß, Achim; Schuster, Alexander K; Kölb-Keerl, Ruth; Knuf, Markus; Kirchhof, Bernd; Muether, Philipp S; Bauer, Jacqueline

    2017-12-01

    To compare corneal aberrations in former preterm infants to that of full-term infants. A prospective cross-sectional study was carried out measuring the corneal shape with Scheimpflug imaging in former preterm infants of gestational age (GA) ≤32 weeks and full-term infants with GA ≥37 weeks now being aged between 4 to 10 years. The main outcome measures were corneal aberrations including astigmatism (Zernike: Z2-2; Z22), coma (Z3-1; Z31), trefoil (Z3-3; Z33), spherical aberration (Z40) and root-mean square of higher-order aberrations (RMS HOA). Multivariable analysis was performed to assess independent associations of gestational age groups and of retinopathy of prematurity (ROP) occurrence with corneal aberrations adjusting for sex and age at examination. A total of 259 former full-term and 226 preterm infants with a mean age of 7.2 ± 2.0 years were included in this study. Statistical analysis revealed an association of extreme prematurity (GA ≤28 weeks) with higher-order and lower-order aberrations of the total cornea. Vertical coma was higher in extreme prematurity (P < 0.001), due to the shape of the anterior corneal surface, while there was no association with trefoil and spherical aberration. ROP was not associated with higher-order aberrations when adjusted for gestational age group. This study demonstrated that specific corneal aberrations were associated with extreme prematurity rather than with ROP occurrence.

  1. Obtaining Information from Family Caregivers Is Important to Detect Behavioral and Psychological Symptoms and Caregiver Burden in Subjects with Mild Cognitive Impairment.

    PubMed

    Yamagami, Tetsuya; Harada, Kazuhiro; Hashidate, Hiroyuki; Asakawa, Yasuyoshi; Nihei, Kenji; Kaneya, Satomi; Yoshii, Chiharu

    2016-01-01

    The objectives of this study are to clarify the differences between the difficulties in daily life experienced by patients with both mild cognitive impairment (MCI) and chronic disease and those experienced by healthy elderly individuals. We assessed (a) cognitive function; (b) gait ability; (c) behavioral and psychological symptoms (observed at home); (d) activities of daily living (observed at home); (e) family caregiver burden, and (f) intention to continue family caregiving of 255 cognitively normal and 103 MCI subjects attending adult day care services covered by long-term care insurance, and compared the two groups. Subjects with MCI display more behavioral and psychological symptoms than cognitively normal subjects, posing a heavy caregiver burden (p < 0.01). Behavioral and psychological symptoms most commonly observed in subjects with MCI are apathy, hallucinations, delusions, agitation, and aberrant motor behavior. Information regarding the behavioral and psychological symptoms displayed at home by patients with MCI can only be obtained from family caregivers living with the patients. To provide early-stage support for elderly patients with MCI, adult day care workers should collect information from family caregivers regarding behavioral and psychological symptoms observed at home.

  2. Measurements of Particulates in Solid Propellant Rocket Motors

    DTIC Science & Technology

    1987-10-01

    gradients created during a firing, however, could be a problem. Finally, a torch was placed in the motor to study temperature effects. The nitrogen...techniques available for studying particulate behavior in solid propellant rocket motors is holography. For the exposed scene a hologram provides both...is underway to study the effects of addition of aluminum and other metallic particles on the magnitude of the performance losses in propellant motors

  3. A Direct Comparison of Self-Injurious and Stereotyped Motor Behavior Between Preschool-Aged Children With and Without Developmental Delays

    PubMed Central

    Spofford, Lisa; Dimian, Adele; Tervo, Raymond; MacLean, William E.; Symons, Frank J.

    2016-01-01

    Objective To compare the prevalence of self-injurious behavior (SIB) and stereotyped motor behavior (STY) of preschool-aged children with developmental delays (DD group) and their peers without developmental delays (TD group) using a standardized caregiver report scale. Methods The Repetitive Behavior Scale-Revised was completed by caregivers of children with developmental delays and their peers without developmental delays. Frequency of occurrence and severity ratings for SIB and STY were compared between groups. Results SIB and STY were reported more often and at a greater level of severity in the DD group. Older chronological age was associated with more severe STY in the DD group but not the TD group. Gender was not related to STY or SIB for either group. Conclusions Differences in STY and SIB were evident between preschoolers with and without DD. Findings are discussed from developmental and behavioral psychology perspectives regarding the expression of repetitive behavior in developmentally at-risk pediatric populations. PMID:26514642

  4. Mind wandering and motor control: off-task thinking disrupts the online adjustment of behavior.

    PubMed

    Kam, Julia W Y; Dao, Elizabeth; Blinn, Patricia; Krigolson, Olav E; Boyd, Lara A; Handy, Todd C

    2012-01-01

    Mind wandering episodes have been construed as periods of "stimulus-independent" thought, where our minds are decoupled from the external sensory environment. In two experiments, we used behavioral and event-related potential (ERP) measures to determine whether mind wandering episodes can also be considered as periods of "response-independent" thought, with our minds disengaged from adjusting our behavioral outputs. In the first experiment, participants performed a motor tracking task and were occasionally prompted to report whether their attention was "on-task" or "mind wandering." We found greater tracking error in periods prior to mind wandering vs. on-task reports. To ascertain whether this finding was due to attenuation in visual perception per se vs. a disruptive effect of mind wandering on performance monitoring, we conducted a second experiment in which participants completed a time-estimation task. They were given feedback on the accuracy of their estimations while we recorded their EEG, and were also occasionally asked to report their attention state. We found that the sensitivity of behavior and the P3 ERP component to feedback signals were significantly reduced just prior to mind wandering vs. on-task attentional reports. Moreover, these effects co-occurred with decreases in the error-related negativity elicited by feedback signals (fERN), a direct measure of behavioral feedback assessment in cortex. Our findings suggest that the functional consequences of mind wandering are not limited to just the processing of incoming stimulation per se, but extend as well to the control and adjustment of behavior.

  5. Mind wandering and motor control: off-task thinking disrupts the online adjustment of behavior

    PubMed Central

    Kam, Julia W. Y.; Dao, Elizabeth; Blinn, Patricia; Krigolson, Olav E.; Boyd, Lara A.; Handy, Todd C.

    2012-01-01

    Mind wandering episodes have been construed as periods of “stimulus-independent” thought, where our minds are decoupled from the external sensory environment. In two experiments, we used behavioral and event-related potential (ERP) measures to determine whether mind wandering episodes can also be considered as periods of “response-independent” thought, with our minds disengaged from adjusting our behavioral outputs. In the first experiment, participants performed a motor tracking task and were occasionally prompted to report whether their attention was “on-task” or “mind wandering.” We found greater tracking error in periods prior to mind wandering vs. on-task reports. To ascertain whether this finding was due to attenuation in visual perception per se vs. a disruptive effect of mind wandering on performance monitoring, we conducted a second experiment in which participants completed a time-estimation task. They were given feedback on the accuracy of their estimations while we recorded their EEG, and were also occasionally asked to report their attention state. We found that the sensitivity of behavior and the P3 ERP component to feedback signals were significantly reduced just prior to mind wandering vs. on-task attentional reports. Moreover, these effects co-occurred with decreases in the error-related negativity elicited by feedback signals (fERN), a direct measure of behavioral feedback assessment in cortex. Our findings suggest that the functional consequences of mind wandering are not limited to just the processing of incoming stimulation per se, but extend as well to the control and adjustment of behavior. PMID:23248596

  6. Quality factor analysis for aberrated laser beam

    NASA Astrophysics Data System (ADS)

    Ghafary, B.; Alavynejad, M.; Kashani, F. D.

    2006-12-01

    The quality factor of laser beams has attracted considerable attention and some different approaches have been reported to treat the problem. In this paper we analyze quality factor of laser beam and compare the effect of different aberrations on beam quality by expanding pure phase term of wavefront in terms of Zernike polynomials. Also we analyze experimentally the change of beam quality for different Astigmatism aberrations, and compare theoretical results with experimentally results. The experimental and theoretical results are in good agreement.

  7. Assisting People with Multiple Disabilities and Minimal Motor Behavior to Improve Computer Drag-and-Drop Efficiency through a Mouse Wheel

    ERIC Educational Resources Information Center

    Shih, Ching-Hsiang

    2011-01-01

    This study evaluated whether two people with multiple disabilities and minimal motor behavior would be able to improve their Drag-and-Drop (DnD) performance using their finger/thumb poke ability with a mouse scroll wheel through a Dynamic Drag-and-Drop Assistive Program (DDnDAP). A multiple probe design across participants was used in this study…

  8. Optical aberrations measurement with a low cost optometric instrument

    NASA Astrophysics Data System (ADS)

    Furlan, Walter D.; Muñoz-Escrivá, L.; Pons, A.; Martínez-Corral, M.

    2002-08-01

    A simple experimental method for measuring optical aberrations of a single lens is proposed. The technique is based on the use of an optometric instrument employed for the assessment of the refractive state of the eye: the retinoscope. Experimental results for spherical aberration and astigmatism are obtained.

  9. Prenatal chlorpyrifos exposure alters motor behavior and ultrasonic vocalization in cd-1 mouse pups

    PubMed Central

    2009-01-01

    Background Chlorpyrifos (CPF) is a non-persistent organophosphate (OP) largely used as pesticide. Studies from animal models indicate that CPF is a developmental neurotoxicant able to target immature central nervous system at dose levels well below the threshold of systemic toxicity. So far, few data are available on the potential short- and long-term adverse effects in children deriving from low-level exposures during prenatal life and infancy. Methods Late gestational exposure [gestational day (GD) 14–17] to CPF at the dose of 6 mg/kg was evaluated in CD-1 mice during early development, by assessment of somatic and sensorimotor maturation [reflex-battery on postnatal days (PNDs) 3, 6, 9, 12 and 15] and ultrasound emission after isolation from the mother and siblings (PNDs 4, 7 and 10). Pups' motor skills were assessed in a spontaneous activity test on PND 12. Maternal behavior of lactating dams in the home cage and in response to presentation of a pup previously removed from the nest was scored on PND 4, to verify potential alterations in maternal care directly induced by CPF administration. Results As for the effects on the offspring, results indicated that on PND 10, CPF significantly decreased number and duration of ultrasonic calls while increasing latency to emit the first call after isolation. Prenatal CPF also reduced motor behavior on PND 12, while a tendency to hyporeflexia was observed in CPF pups by means of reflex-battery scoring. Dams administered during gestation with CPF showed baseline levels of maternal care comparable to those of controls, but higher levels of both pup-directed (licking) and explorative (wall rearing) responses. Conclusion Overall our results are consistent with previous epidemiological data on OP neurobehavioral toxicity, and also indicate ultrasonic vocalization as an early marker of CPF exposure during development in rodent studies, with potential translational value to human infants. PMID:19331648

  10. Analysis of nodal aberration properties in off-axis freeform system design.

    PubMed

    Shi, Haodong; Jiang, Huilin; Zhang, Xin; Wang, Chao; Liu, Tao

    2016-08-20

    Freeform surfaces have the advantage of balancing off-axis aberration. In this paper, based on the framework of nodal aberration theory (NAT) applied to the coaxial system, the third-order astigmatism and coma wave aberration expressions of an off-axis system with Zernike polynomial surfaces are derived. The relationship between the off-axis and surface shape acting on the nodal distributions is revealed. The nodal aberration properties of the off-axis freeform system are analyzed and validated by using full-field displays (FFDs). It has been demonstrated that adding Zernike terms, up to nine, to the off-axis system modifies the nodal locations, but the field dependence of the third-order aberration does not change. On this basis, an off-axis two-mirror freeform system with 500 mm effective focal length (EFL) and 300 mm entrance pupil diameter (EPD) working in long-wave infrared is designed. The field constant aberrations induced by surface tilting are corrected by selecting specific Zernike terms. The design results show that the nodes of third-order astigmatism and coma move back into the field of view (FOV). The modulation transfer function (MTF) curves are above 0.4 at 20 line pairs per millimeter (lp/mm) which meets the infrared reconnaissance requirement. This work provides essential insight and guidance for aberration correction in off-axis freeform system design.

  11. Effects of ocular aberrations on contrast detection in noise.

    PubMed

    Liang, Bo; Liu, Rong; Dai, Yun; Zhou, Jiawei; Zhou, Yifeng; Zhang, Yudong

    2012-08-06

    We use adaptive optics (AO) techniques to manipulate the ocular aberrations and elucidate the effects of these ocular aberrations on contrast detection in a noisy background. The detectability of sine wave gratings at frequencies of 4, 8, and 16 circles per degree (cpd) was measured in a standard two-interval force-choice staircase procedure against backgrounds of various levels of white noise. The observer's ocular aberrations were either corrected with AO or left uncorrected. In low levels of external noise, contrast detection thresholds are always lowered by AO correction, whereas in high levels of external noise, they are generally elevated by AO correction. Higher levels of external noise are required to make this threshold elevation observable when signal spatial frequencies increase from 4 to 16 cpd. The linear-amplifier-model fit shows that mostly sampling efficiency and equivalent noise both decrease with AO correction. Our findings indicate that ocular aberrations could be beneficial for contrast detection in high-level noises. The implications of these findings are discussed.

  12. Design for an aberration corrected scanning electron microscope using miniature electron mirrors.

    PubMed

    Dohi, Hideto; Kruit, Pieter

    2018-06-01

    Resolution of scanning electron microscopes (SEMs) is determined by aberrations of the objective lens. It is well known that both spherical and chromatic aberrations can be compensated by placing a 90-degree bending magnet and an electron mirror in the beam path before the objective lens. Nevertheless, this approach has not led to wide use of these aberration correctors, partly because aberrations of the bending magnet can be a serious problem. A mirror corrector with two mirrors placed perpendicularly to the optic axis of an SEM and facing each other is proposed. As a result, only small-angle magnetic deflection is necessary to guide the electron beam around the top mirror to the bottom mirror and around the bottom mirror to the objective lens. The deflection angle, in the order of 50 mrad, is sufficiently small to avoid deflection aberrations. In addition, lateral dispersion at the sample plane can be avoided by making the deflection fields symmetric. Such a corrector system is only possible if the incoming beam can pass the top mirror at a distance in the order of millimeters, without being disturbed by the electric fields of electrodes of the mirror. It is proposed that condition can be satisfied with micro-scale electron optical elements fabricated by using MEMS technology. In the proposed corrector system, the micro-mirrors have to provide the exact negative spherical and chromatic aberrations for correcting the aberration of the objective lens. This exact tuning is accomplished by variable magnification between the micro-mirrors and the objective lens using an additional transfer lens. Extensive optical calculations are reported. Aberrations of the micro-mirrors were analyzed by numerical calculation. Dispersion and aberrations of the deflectors were calculated by using an analytical field model. Combination aberrations caused by the off-axis position of dispersive rays in the mirrors and objective lens were also analyzed. It is concluded that the proposed

  13. Sources of the monochromatic aberrations induced in human eyes after laser refractive surgery

    NASA Astrophysics Data System (ADS)

    Porter, Jason

    Laser in-situ keratomileusis (LASIK) procedures correct the eye's defocus and astigmatism but also introduce higher order monochromatic aberrations. Little is known about the origins of these induced aberrations. The advent of wavefront sensor technology has made it possible to measure accurately and quickly the aberrations of normal and postoperative LASIK eyes. The goal of this thesis was to exploit this technology to better understand some of the potential mechanisms by which aberrations could be introduced during LASIK. A first step towards investigating these sources was to characterize the aberration changes in post-LASIK eyes. Higher order rms wavefront error increased after conventional and customized LASIK surgery. On average, spherical aberration approximately doubled, and significant changes in vertical and horizontal coma were observed. We examined two sources of postoperative aberrations: the creation of a microkeratome flap and the subsequent laser ablation. Higher order rms increased slightly and there was a wide variation in the response of individual Zernike modes after cutting a flap. The majority of induced spherical aberration was due to the laser ablation and not the flap-cut. Aberrations are also induced by static and dynamic decentrations of the patient's pupil. We found that ablations were typically decentered in the superotemporal direction due to shifts in pupil center location between aberration measurement (dilated) and surgical (undilated) conditions in customized LASIK eyes. There was a weak correlation between the horizontal coma theoretically induced by this offset and that measured postoperatively. Finally, dynamic eye movements during the procedure induce higher order aberrations. We found that the most problematic decentrations during LASIK are relatively slow drifts in eye position. An eye-tracking system with a 2-Hz closed-loop bandwidth could compensate for most eye movements during LASIK. One solution for reducing the

  14. Variability of higher order wavefront aberrations after blinks.

    PubMed

    Hagyó, Krisztina; Csákány, Béla; Lang, Zsolt; Németh, János

    2009-01-01

    To investigate the rapid alterations in value and fluctuation of ocular wavefront aberrations during the interblink interval. Forty-two volunteers were examined with a WASCA Wavefront Analyzer (Carl Zeiss Meditec AG) using modified software. For each subject, 150 images (about 6 frames/second) were registered during an interblink period. The outcome measures were spherical and cylindrical refraction and root-mean-square (RMS) values for spherical, coma, and total higher order aberrations. Fifth order polynomials were fitted to the data and the fluctuation trends of the parameters were determined. We calculated the prevalence of the trends with an early local minimum (type 1). The tear production status (Schirmer test) and tear film break-up time (BUT) were also measured. Fluctuation trends with an early minimum (type 1) were significantly more frequent than trends with an early local maximum (type 2) for total higher order aberrations RMS (P=.036). The incidence of type 1 fluctuation trends was significantly greater for coma and total higher order aberrations RMS (P=.041 and P=.003, respectively) in subjects with normal results in the BUT or Schirmer test than in those with abnormal results. In the normal subjects, the first minimum of type 1 RMS fluctuation trends occurred, on average, between 3.8 and 5.1 seconds after blink. We suggest that wavefront aberrations can be measured most accurately at the time after blink when they exhibit a decreased degree of dispersion. We recommend that a snapshot of wavefront measurements be made 3 to 5 seconds after blink.

  15. Construction of special eye models for investigation of chromatic and higher-order aberrations of eyes.

    PubMed

    Zhai, Yi; Wang, Yan; Wang, Zhaoqi; Liu, Yongji; Zhang, Lin; He, Yuanqing; Chang, Shengjiang

    2014-01-01

    An achromatic element eliminating only longitudinal chromatic aberration (LCA) while maintaining transverse chromatic aberration (TCA) is established for the eye model, which involves the angle formed by the visual and optical axis. To investigate the impacts of higher-order aberrations on vision, the actual data of higher-order aberrations of human eyes with three typical levels are introduced into the eye model along visual axis. Moreover, three kinds of individual eye models are established to investigate the impacts of higher-order aberrations, chromatic aberration (LCA+TCA), LCA and TCA on vision under the photopic condition, respectively. Results show that for most human eyes, the impact of chromatic aberration on vision is much stronger than that of higher-order aberrations, and the impact of LCA in chromatic aberration dominates. The impact of TCA is approximately equal to that of normal level higher-order aberrations and it can be ignored when LCA exists.

  16. Aberrant alternative splicing is another hallmark of cancer.

    PubMed

    Ladomery, Michael

    2013-01-01

    The vast majority of human genes are alternatively spliced. Not surprisingly, aberrant alternative splicing is increasingly linked to cancer. Splice isoforms often encode proteins that have distinct and even antagonistic properties. The abnormal expression of splice factors and splice factor kinases in cancer changes the alternative splicing of critically important pre-mRNAs. Aberrant alternative splicing should be added to the growing list of cancer hallmarks.

  17. Modeling an electric motor in 1-D

    NASA Technical Reports Server (NTRS)

    Butler, Thomas G.

    1991-01-01

    Quite often the dynamicist will be faced with having an electric drive motor as a link in the elastic path of a structure such that the motor's characteristics must be taken into account to properly represent the dynamics of the primary structure. He does not want to model it so accurately that he could get detailed stress and displacements in the motor proper, but just sufficiently to represent its inertia loading and elastic behavior from its mounting bolts to its drive coupling. Described here is how the rotor and stator of such a motor can be adequately modeled as a colinear pair of beams.

  18. Learning-performance distinction and memory processes for motor skills: a focused review and perspective.

    PubMed

    Kantak, Shailesh S; Winstein, Carolee J

    2012-03-01

    Behavioral research in cognitive psychology provides evidence for an important distinction between immediate performance that accompanies practice and long-term performance that reflects the relative permanence in the capability for the practiced skill (i.e. learning). This learning-performance distinction is strikingly evident when challenging practice conditions may impair practice performance, but enhance long-term retention of motor skills. A review of motor learning studies with a specific focus on comparing differences in performance between that at the end of practice and at delayed retention suggests that the delayed retention or transfer performance is a better indicator of motor learning than the performance at (or end of) practice. This provides objective evidence for the learning-performance distinction. This behavioral evidence coupled with an understanding of the motor memory processes of encoding, consolidation and retrieval may provide insight into the putative mechanism that implements the learning-performance distinction. Here, we propose a simplistic empirically-based framework--motor behavior-memory framework--that integrates the temporal evolution of motor memory processes with the time course of practice and delayed retention frequently used in behavioral motor learning paradigms. In the context of the proposed framework, recent research has used noninvasive brain stimulation to decipher the role of each motor memory process, and specific cortical brain regions engaged in motor performance and learning. Such findings provide beginning insights into the relationship between the time course of practice-induced performance changes and motor memory processes. This in turn has promising implications for future research and practical applications. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Spatially resolved wavefront aberrations of ophthalmic progressive-power lenses in normal viewing conditions.

    PubMed

    Villegas, Eloy A; Artal, Pablo

    2003-02-01

    To measure the wavefront aberration at different locations in progressive-power lenses (PPL's) isolated and in situ (PPL's plus eye). A Hartmann-Shack wavefront sensor was used to measure progressive-power lenses and human eyes either independently or in combination. In each selected zone, the lens was placed and tilted accordingly to simulate natural viewing conditions. We measured 21 relevant locations across an isolated PPL (plano lens of power addition of 2 D). In six of the locations, the wavefront aberration of the eye plus PPL were obtained in two ways: (1) by direct measurement of the system and (2) by adding the individual wavefront aberrations of the eye and the lens for each appropriate zone. In every case, we obtained the wavefront aberration as Zernike polynomials expansions, the root mean square error, the point-spread function, and the Strehl ratio. Along the corridor of the PPL, third-order coma and trefoil, and astigmatism were the dominant aberrations. In areas of the PPL outside the corridor, astigmatism increased, whereas other aberrations remained similar to the lens center. Small differences were found between the direct and calculated methods used to obtain the wavefront aberration of the eye with the lens, and the possible sources of errors were discussed. In some lenses zones, the aberrations of the lens may be compensated by the particular aberrations of the eye, yielding improved optical performance over that present in the lens alone. We designed and built a wavefront sensor to perform spatially resolved aberration measurements in ophthalmic lenses, in particular in PPL's, either isolated or in combination with the eye. The aberrations appearing in the PPL were compared with those in normal aged eyes.

  20. The Lunacy of It All: Lunar Phases and Human Behavior.

    ERIC Educational Resources Information Center

    Rotton, James; Kelly, Ivan W.

    1986-01-01

    Discusses the relationship between aberrant human behavior and phases of the moon. Reviews media influence, myth, superstition and pseudoscience. Examines studies purporting to have found relationships between moon phases and behavior. (JM)