Discharge properties of hippocampal neurons during performance of a jump avoidance task

PubMed Central

Lenck-Santini, Pierre-Pascal; Fenton, André A.; Muller, Robert U.

2008-01-01

We recorded single hippocampal cells while rats performed a jump avoidance task. In this task, a rat was dropped onto the metal floor of a 33 cm gray wooden cube and was given a mild electric shock if it did not jump up onto the box rim in less than 15 sec. We found that many hippocampal pyramidal cells and most interneurons discharged preferentially at either the drop, the jump or on both events. By simultaneously recording the hippocampal EEG, we found that the discharge of most of the event-related pyramidal cells was modulated by the theta rhythm and moreover that discharge precessed with theta cycles in the same fashion seen for pyramidal cells in their role as place cells. The elevations of firing rate at drop and jump were accompanied by increases in theta frequency. We conclude that many of the features of event-related discharge can be interpreted as being equivalent to the activity of place cells with firing fields above the box floor. Nevertheless, there are sufficient differences between expectations from place cells and observed activity to indicate that pyramidal cells may be able to signal events as well as location. PMID:18596153

Trait Approach and Avoidance Motivation: Lateralized Neural Activity Associated with Executive Function

PubMed Central

Spielberg, Jeffrey M.; Miller, Gregory A.; Engels, Anna S.; Herrington, John D.; Sutton, Bradley P.; Banich, Marie T.; Heller, Wendy

2010-01-01

Motivation and executive function are both necessary for the completion of goal-directed behavior. Research investigating the manner in which these processes interact is beginning to emerge and has implicated middle frontal gyrus (MFG) as a site of interaction for relevant neural mechanisms. However, this research has focused on state motivation, and it has not examined functional lateralization. The present study examined the impact of trait levels of approach and avoidance motivation on neural processes associated with executive function. Functional magnetic resonance imaging was conducted while participants performed a color-word Stroop task. Analyses identified brain regions in which trait approach and avoidance motivation (measured by questionnaires) moderated activation associated with executive control. Approach was hypothesized to be associated with left-lateralized MFG activation, whereas avoidance was hypothesized to be associated with right-lateralized MFG activation. Results supported both hypotheses. Present findings implicate areas of middle frontal gyrus in top-down control to guide behavior in accordance with motivational goals. PMID:20728552

Dual tasking negatively impacts obstacle avoidance abilities in post-stroke individuals with visuospatial neglect: Task complexity matters!

PubMed

Aravind, Gayatri; Lamontagne, Anouk

2017-01-01

Persons with perceptual-attentional deficits due to visuospatial neglect (VSN) after a stroke are at a risk of collisions while walking in the presence of moving obstacles. The attentional burden of performing a dual-task may further compromise their obstacle avoidance performance, putting them at a greater risk of collisions. The objective of this study was to compare the ability of persons with (VSN+) and without VSN (VSN-) to dual task while negotiating moving obstacles. Twenty-six stroke survivors (13 VSN+, 13 VSN-) were assessed on their ability to (a) negotiate moving obstacles while walking (locomotor single task); (b) perform a pitch-discrimination task (cognitive single task) and (c) simultaneously perform the walking and cognitive tasks (dual task). We compared the groups on locomotor (collision rates, minimum distance from obstacle and onset of strategies) and cognitive (error rates) outcomes. For both single and dual task walking, VSN+ individuals showed higher collision rates compared to VSN- individuals. Dual tasking caused deterioration of locomotor (more collisions, delayed onset and smaller minimum distances) and cognitive performances (higher error rate) in VSN+ individuals. Contrastingly, VSN- individuals maintained collision rates, increased minimum distance, but showed more cognitive errors, prioritizing their locomotor performance. Individuals with VSN demonstrate cognitive-locomotor interference under dual task conditions, which could severely compromise safety when ambulating in community environments and may explain the poor recovery of independent community ambulation in these individuals.

A Teacher-Report Measure of Children's Task-Avoidant Behavior: A Validation Study of the Behavioral Strategy Rating Scale

ERIC Educational Resources Information Center

Zhang, Xiao; Nurmi, Jari-Erik; Kiuru, Noona; Lerkkanen, Marja-Kristiina; Aunola, Kaisa

2011-01-01

This study aims to validate a teacher-report measure of children's task-avoidant behavior, namely the Behavioral Strategy Rating Scale (BSRS), in a sample of 352 Finnish children. In each of the four waves from Kindergarten to Grade 2, teachers rated children's task-avoidant behavior using the BSRS, children completed reading and mathematics…

Individual differences in sensitivity to reward and punishment and neural activity during reward and avoidance learning

PubMed Central

Yoon, HeungSik; Kim, Hackjin; Hamann, Stephan

2015-01-01

In this functional neuroimaging study, we investigated neural activations during the process of learning to gain monetary rewards and to avoid monetary loss, and how these activations are modulated by individual differences in reward and punishment sensitivity. Healthy young volunteers performed a reinforcement learning task where they chose one of two fractal stimuli associated with monetary gain (reward trials) or avoidance of monetary loss (avoidance trials). Trait sensitivity to reward and punishment was assessed using the behavioral inhibition/activation scales (BIS/BAS). Functional neuroimaging results showed activation of the striatum during the anticipation and reception periods of reward trials. During avoidance trials, activation of the dorsal striatum and prefrontal regions was found. As expected, individual differences in reward sensitivity were positively associated with activation in the left and right ventral striatum during reward reception. Individual differences in sensitivity to punishment were negatively associated with activation in the left dorsal striatum during avoidance anticipation and also with activation in the right lateral orbitofrontal cortex during receiving monetary loss. These results suggest that learning to attain reward and learning to avoid loss are dependent on separable sets of neural regions whose activity is modulated by trait sensitivity to reward or punishment. PMID:25680989

Low-dose memantine-induced working memory improvement in the allothetic place avoidance alternation task (APAAT) in young adult male rats

PubMed Central

Wesierska, Malgorzata J.; Duda, Weronika; Dockery, Colleen A.

2013-01-01

N-methyl-D-aspartate receptors (NMDAR) are involved in neuronal plasticity. To assess their role simultaneously in spatial working memory and non-cognitive learning, we used NMDAR antagonists and the Allothetic Place Avoidance Alternation Task (APAAT). In this test rats should avoid entering a place where shocks were presented on a rotating arena which requires cognitive coordination for the segregation of stimuli. The experiment took place 30 min after intraperitoneal injection of memantine (5, 10, 20 mg/kg b.w.: MemL, MemM, MemH, respectively) and (+)MK-801 (0.1, 0.2, 0.3 mg/kg b.w.: MK-801L, MK-801M, MK-801H, respectively). Rats from the control group were intact or injected with saline (0.2 ml/kg). Over three consecutive days the rats underwent habituation, two avoidance training intervals with shocks, and a retrieval test. The shock sector was alternated daily. The after-effects of the agents were tested on Day 21. Rats treated with low dose memantine presented a longer maximum time avoided and fewer entrances than the MemH, MK-801M, MK-801H and Control rats. The shocks per entrances ratio, used as an index of cognitive skill learning, showed skill improvement after D1, except for rats treated by high doses of the agents. The activity levels, indicated by the distance walked, were higher for the groups treated with high doses of the agents. On D21 the MK801H rats performed the memory task better than the MemH rats, whereas the rats' activity depended on condition, not on the group factor. These results suggest that in naïve rats mild NMDAR blockade by low-dose memantine improves working memory related to a highly challenging task. PMID:24385956

Trait approach and avoidance motivation: lateralized neural activity associated with executive function.

PubMed

Spielberg, Jeffrey M; Miller, Gregory A; Engels, Anna S; Herrington, John D; Sutton, Bradley P; Banich, Marie T; Heller, Wendy

2011-01-01

Motivation and executive function are both necessary for the completion of goal-directed behavior. Research investigating the manner in which these processes interact is beginning to emerge and has implicated middle frontal gyrus (MFG) as a site of interaction for relevant neural mechanisms. However, this research has focused on state motivation, and it has not examined functional lateralization. The present study examined the impact of trait levels of approach and avoidance motivation on neural processes associated with executive function. Functional magnetic resonance imaging was conducted while participants performed a color-word Stroop task. Analyses identified brain regions in which trait approach and avoidance motivation (measured by questionnaires) moderated activation associated with executive control. Approach was hypothesized to be associated with left-lateralized MFG activation, whereas avoidance was hypothesized to be associated with right-lateralized MFG activation. Results supported both hypotheses. Present findings implicate areas of middle frontal gyrus in top-down control to guide behavior in accordance with motivational goals. Copyright © 2010 Elsevier Inc. All rights reserved.

A spatial paradigm, the allothetic place avoidance alternation task, for testing visuospatial working memory and skill learning in rats.

PubMed

Dockery, Colleen A; Wesierska, Malgorzata J

2010-08-30

We present a paradigm for assessing visuospatial working memory and skill learning in a rodent model, based on the place avoidance test. In our allothetic place avoidance alternation task (APAAT) the paradigm is comprised of minimal training sessions, tests various aspects of learning and memory and provides a rich set of parameters. A single working memory session consists of four conditions: habituation (no shock), two place avoidance training intervals (shock activated) and a retrieval test (shock inactivated). The location of the shock sector is alternated for each training day which initially requires extinction of previous representations and further working memory to achieve effective place avoidance across sessions. Visuospatial skill memory was evaluated by the shock/entrance ratio by tracking locomotor activity which is essential to execute a place avoidance strategy. For each day rats learned to avoid a new place with shock, as shown by a decreased number of entrances, and an increased time to the first entrance and maximum avoidance time. Skill learning improved according to the decreased number of shocks per entrance across conditions. These results indicate that complex cognitive functions are captured by this behavioral method. This APAAT paradigm expands and complements existing tools for studying hippocampal-prefrontal dependent functions to support development of treatment interventions. Copyright (c) 2010 Elsevier B.V. All rights reserved.

GMP reverses the facilitatory effect of glutamate on inhibitory avoidance task in rats.

PubMed

Rubin, M A; Jurach, A; da Costa Júnior, E M; Lima, T T; Jiménez-Bernal, R E; Begnini, J; Souza, D O; de Mello, C F

1996-09-02

Previous studies have demonstrated that post-training intrahippocampal glutamate administration improves inhibitory avoidance task performance in rats. Antagonism of the agonist actions of glutamate by guanine nucleotides has been shown at the molecular and behavioural level. In the present investigation we demonstrate that intrahippocampal co-administration of GMP (guanosine 5'-monophosphate) reverses the facilitatory effect of glutamate on the inhibitory avoidance learning paradigm and inhibits [3H]glutamate binding in hippocampal synaptic plasma membranes. These results suggest that guanine nucleotides may modulate glutamate actions.

Predictors of task-persistent and fear-avoiding behaviors in women with sexual pain disorders.

PubMed

Brauer, Marieke; Lakeman, Mariëlle; van Lunsen, Rik; Laan, Ellen

2014-12-01

Dyspareunia and vaginismus are the most common sexual pain disorders (SPDs). Literature suggests that many women with dyspareunia continue with intercourse despite pain (task persistence), whereas many women with vaginismus avoid penetrative activities that may cause pain (fear avoidance). Both forms of sexual pain behavior may maintain or aggravate complaints. This study examined (i) whether women with SPD differ from pain-free controls in motives for sexual intercourse, sexual autonomy, maladaptive beliefs regarding vaginal penetration, and partner responses to pain; and (ii) which of these factors best predict whether women with SPD stop or continue painful intercourse (attempts). Women with superficial dyspareunia (n = 50), women with lifelong vaginismus (n = 20), and pain-free controls (n = 45) completed questionnaires. For Aim 1, the main outcome measures were (i) motives for intercourse; (ii) sexual autonomy; (iii) maladaptive beliefs regarding vaginal penetration; and (iv) partner responses to pain. For Aim 2, sexual pain behavior (to continue or discontinue with painful intercourse) was the outcome measure. (i) Women with dyspareunia exhibited more mate guarding and duty/pressure motives for intercourse and were less sexually autonomous than controls. (ii) Symptomatic women had more maladaptive penetration-related beliefs than controls, with women with vaginismus reporting the strongest maladaptive beliefs. (iii) Partners of women with dyspareunia self-reported more negative responses to pain than those of women with vaginismus. (iv) The factors that best predicted sexual pain behavior were the partner responses to pain and the woman's maladaptive beliefs regarding vaginal penetration. Our findings reveal support for task persistence in women with dyspareunia and fear avoidance in women with lifelong vaginismus. As such, it is important to consider these distinct types of responding to sexual pain when treating SPD. © 2014 International

Individual differences in sensitivity to reward and punishment and neural activity during reward and avoidance learning.

PubMed

Kim, Sang Hee; Yoon, HeungSik; Kim, Hackjin; Hamann, Stephan

2015-09-01

In this functional neuroimaging study, we investigated neural activations during the process of learning to gain monetary rewards and to avoid monetary loss, and how these activations are modulated by individual differences in reward and punishment sensitivity. Healthy young volunteers performed a reinforcement learning task where they chose one of two fractal stimuli associated with monetary gain (reward trials) or avoidance of monetary loss (avoidance trials). Trait sensitivity to reward and punishment was assessed using the behavioral inhibition/activation scales (BIS/BAS). Functional neuroimaging results showed activation of the striatum during the anticipation and reception periods of reward trials. During avoidance trials, activation of the dorsal striatum and prefrontal regions was found. As expected, individual differences in reward sensitivity were positively associated with activation in the left and right ventral striatum during reward reception. Individual differences in sensitivity to punishment were negatively associated with activation in the left dorsal striatum during avoidance anticipation and also with activation in the right lateral orbitofrontal cortex during receiving monetary loss. These results suggest that learning to attain reward and learning to avoid loss are dependent on separable sets of neural regions whose activity is modulated by trait sensitivity to reward or punishment. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

A bio-inspired kinematic controller for obstacle avoidance during reaching tasks with real robots.

PubMed

Srinivasa, Narayan; Bhattacharyya, Rajan; Sundareswara, Rashmi; Lee, Craig; Grossberg, Stephen

2012-11-01

This paper describes a redundant robot arm that is capable of learning to reach for targets in space in a self-organized fashion while avoiding obstacles. Self-generated movement commands that activate correlated visual, spatial and motor information are used to learn forward and inverse kinematic control models while moving in obstacle-free space using the Direction-to-Rotation Transform (DIRECT). Unlike prior DIRECT models, the learning process in this work was realized using an online Fuzzy ARTMAP learning algorithm. The DIRECT-based kinematic controller is fault tolerant and can handle a wide range of perturbations such as joint locking and the use of tools despite not having experienced them during learning. The DIRECT model was extended based on a novel reactive obstacle avoidance direction (DIRECT-ROAD) model to enable redundant robots to avoid obstacles in environments with simple obstacle configurations. However, certain configurations of obstacles in the environment prevented the robot from reaching the target with purely reactive obstacle avoidance. To address this complexity, a self-organized process of mental rehearsals of movements was modeled, inspired by human and animal experiments on reaching, to generate plans for movement execution using DIRECT-ROAD in complex environments. These mental rehearsals or plans are self-generated by using the Fuzzy ARTMAP algorithm to retrieve multiple solutions for reaching each target while accounting for all the obstacles in its environment. The key aspects of the proposed novel controller were illustrated first using simple examples. Experiments were then performed on real robot platforms to demonstrate successful obstacle avoidance during reaching tasks in real-world environments. Copyright © 2012 Elsevier Ltd. All rights reserved.

Inhibition of long-term memory formation by anti-ependymin antisera after active shock-avoidance learning in goldfish.

PubMed

Piront, M L; Schmidt, R

1988-02-23

Ependymins are acidic glycoprotein constituents of goldfish brain cytoplasm and extracellular fluid which are known to participate in biochemical reactions of long-term memory formation. In earlier experiments, anti-ependymin antisera were found to cause amnesia when injected into goldfish brain ventricles after the acquisition of a vestibulomotoric training task. To investigate whether they also inhibit memory consolidation after other learning events the anti-ependymin antisera were injected after an active shock-avoidance learning paradigm, as follows: goldfish were trained in a shuttle-box to cross a barrier in order to avoid electric shocks (unconditioned stimulus) applied shortly after a light signal (conditioned stimulus). Anti-ependymin antisera blocked retention of the learned avoidance when injected 0.5, 4.5 or 24 h after acquisition of the new behavior. They had no effect, however, when injected 72 h after learning. Apparently, long-term memory was already consolidated at this point. Antisera injected 0.5 or 72 h prior to training, also did not influence learning or memory. Thirteen percent of the goldfish fled the light stimulus spontaneously. These fish therefore did not experience the unconditioned stimulus and thus were unable to learn the task. When they were treated with the anti-ependymin antisera and tested 3 days later, the spontaneous escape reaction was not affected (active control group). The ability of anti-ependymin antisera to inhibit memory consolidation and their efficacy after administration at specific time intervals are very similar for the active shock-avoidance learning and for the vestibulomotoric training. We conclude that ependymins are not task-specific, but serve a general function in biochemical reactions essential for long-term memory formation.

Carryover effects associated with the single-trial passive avoidance learning task in the young chick.

PubMed

Crowe, Simon F; Hale, Matthew W

2002-09-01

The single-trial passive avoidance task is a useful procedure for examining learning and memory in the young chick. However, it has recently been suggested that discrepant results reported by different laboratories are due to differences in training procedure. The present study investigated a number of parameters surrounding the passive avoidance task, using day-old White Leghorn, Black Australorp cockerels. The results suggested that presentation of a water-dipped bead immediately after the aversive bead significantly altered retention levels. In addition, when the water-dipped bead was presented after the aversive bead, chicks failed to discriminate between beads for a period of 10 min following exposure to the aversant experience. A novel variant of the passive avoidance procedure, involving pretraining with a water-dipped red bead, training with an aversant-coated red bead, and testing with a dry red bead, was evaluated. A measure of avoidance was calculated using all three trials. It is suggested that the use of a single bead, measured both before and after the training experience and using both aversant- and water-trained controls, results in the most concise characterization of memory-related phenomena in the chick which is not contaminated by a carryover effect from the aversive training experience to the nonaversive bead.

Stimulus conflict triggers behavioral avoidance.

PubMed

Dignath, David; Eder, Andreas B

2015-12-01

According to a recent extension of the conflict-monitoring theory, conflict between two competing response tendencies is registered as an aversive event and triggers a motivation to avoid the source of conflict. In the present study, we tested this assumption. Over five experiments, we examined whether conflict is associated with an avoidance motivation and whether stimulus conflict or response conflict triggers an avoidance tendency. Participants first performed a color Stroop task. In a subsequent motivation test, participants responded to Stroop stimuli with approach- and avoidance-related lever movements. These results showed that Stroop-conflict stimuli increased the frequency of avoidance responses in a free-choice motivation test, and also increased the speed of avoidance relative to approach responses in a forced-choice test. High and low proportions of response conflict in the Stroop task had no effect on avoidance in the motivation test. Avoidance of conflict was, however, obtained even with new conflict stimuli that had not been presented before in a Stroop task, and when the Stroop task was replaced with an unrelated filler task. Taken together, these results suggest that stimulus conflict is sufficient to trigger avoidance.

Avoidant Responses to Interpersonal Provocation Are Associated with Increased Amygdala and Decreased Mentalizing Network Activity

PubMed Central

Krämer, Ulrike M.

2017-01-01

When intentionally pushed or insulted, one can either flee from the provoker or retaliate. The implementation of such fight-or-flight decisions is a central aspect in the genesis and evolution of aggression episodes, yet it is usually investigated only indirectly or in nonsocial situations. In the present fMRI study, we aimed to distinguish brain regions associated with aggressive and avoidant responses to interpersonal provocation in humans. Participants (thirty-six healthy young women) could either avoid or face a highly (HP) and a lowly (LP) provoking opponent in a competitive reaction time task: the fight-or-escape (FOE) paradigm. Subjects avoided the HP more often, but retaliated when facing her. Moreover, they chose to fight the HP more quickly, and showed increased heart rate (HR) right before confronting her. Orbitofrontal cortex (OFC) and sensorimotor cortex were more active when participants decided to fight, whereas the mentalizing network was engaged when deciding to avoid. Importantly, avoiding the HP relative to the LP was associated with both higher activation in the right basolateral amygdala and lower relative activity in several mentalizing regions [e.g., medial and inferior frontal gyrus (IFG), temporal-parietal junction (TPJ)]. These results suggest that avoidant responses to provocation might result from heightened threat anticipation and are associated with reduced perspective taking. Furthermore, our study helps to reconcile conflicting findings on the role of the mentalizing network, the amygdala, and the OFC in aggression. PMID:28660251

INFANT AVOIDANCE DURING A TACTILE TASK PREDICTS AUTISM SPECTRUM BEHAVIORS IN TODDLERHOOD.

PubMed

Mammen, Micah A; Moore, Ginger A; Scaramella, Laura V; Reiss, David; Ganiban, Jody M; Shaw, Daniel S; Leve, Leslie D; Neiderhiser, Jenae M

2015-01-01

The experience of touch is critical for early communication and social interaction; infants who show aversion to touch may be at risk for atypical development and behavior problems. The current study aimed to clarify predictive associations between infant responses to tactile stimuli and toddler autism spectrum, internalizing, and externalizing behaviors. This study measured 9-month-old infants' (N = 561; 58% male) avoidance and negative affect during a novel tactile task in which parents painted infants' hands and feet and pressed them to paper to make a picture. Parent reports on the Pervasive Developmental Problems (PDP), Internalizing, and Externalizing scales of the Child Behavior Checklist were used to measure toddler behaviors at 18 months. Infant observed avoidance and negative affect were significantly correlated; however, avoidance predicted subsequent PDP scores only, independent of negative affect, which did not predict any toddler behaviors. Findings suggest that incorporating measures of responses to touch in the study of early social interaction may provide an important and discriminating construct for identifying children at greater risk for social impairments related to autism spectrum behaviors. © 2015 Michigan Association for Infant Mental Health.

Measurement of food-related approach-avoidance biases: Larger biases when food stimuli are task relevant.

PubMed

Lender, Anja; Meule, Adrian; Rinck, Mike; Brockmeyer, Timo; Blechert, Jens

2018-06-01

Strong implicit responses to food have evolved to avoid energy depletion but contribute to overeating in today's affluent environments. The Approach-Avoidance Task (AAT) supposedly assesses implicit biases in response to food stimuli: Participants push pictures on a monitor "away" or pull them "near" with a joystick that controls a corresponding image zoom. One version of the task couples movement direction with image content-independent features, for example, pulling blue-framed images and pushing green-framed images regardless of content ('irrelevant feature version'). However, participants might selectively attend to this feature and ignore image content and, thus, such a task setup might underestimate existing biases. The present study tested this attention account by comparing two irrelevant feature versions of the task with either a more peripheral (image frame color: green vs. blue) or central (small circle vs. cross overlaid over the image content) image feature as response instruction to a 'relevant feature version', in which participants responded to the image content, thus making it impossible to ignore that content. Images of chocolate-containing foods and of objects were used, and several trait and state measures were acquired to validate the obtained biases. Results revealed a robust approach bias towards food only in the relevant feature condition. Interestingly, a positive correlation with state chocolate craving during the task was found when all three conditions were combined, indicative of criterion validity of all three versions. However, no correlations were found with trait chocolate craving. Results provide a strong case for the relevant feature version of the AAT for bias measurement. They also point to several methodological avenues for future research around selective attention in the irrelevant versions and task validity regarding trait vs. state variables. Copyright © 2018 Elsevier Ltd. All rights reserved.

Responding to a Challenging Perceptual-Motor Task as a Function of Level of Experiential Avoidance

ERIC Educational Resources Information Center

Zettle, Robert D.; Petersen, Connie L.; Hocker, Tanya R.; Provines, Jessica L.

2007-01-01

Participants displaying high versus low levels of experiential avoidance as assessed by the Acceptance and Action Questionnaire (Hayes, Strosahl, et al., 2004) were compared in their reactions to and performance on a challenging perceptual-motor task. Participants were offered incentives for sorting colored straws into different colored containers…

Perseveration effects in detection tasks with correlated decision intervals. [applied to pilot collision avoidance

NASA Technical Reports Server (NTRS)

Gai, E. G.; Curry, R. E.

1978-01-01

An investigation of the behavior of the human decisionmaker is described for a task related to the problem of a pilot using a traffic situation display to avoid collisions. This sequential signal detection task is characterized by highly correlated signals with time varying strength. Experimental results are presented and the behavior of the observers is analyzed using the theory of Markov processes and classical signal detection theory. Mathematical models are developed which describe the main result of the experiment: that correlation in sequential signals induced perseveration in the observer response and a strong tendency to repeat their previous decision, even when they were wrong.

Spaced sessions of avoidance extinction reduce spontaneous recovery and promote infralimbic cortex activation.

PubMed

Tapias-Espinosa, Carles; Kádár, Elisabet; Segura-Torres, Pilar

2018-01-15

Extinction-based therapies (EBT) are the psychological treatments of choice for certain anxiety disorders, such as post-traumatic stress disorder. However, some patients relapse and suffer spontaneous recovery (SR) of anxiety symptoms and persistence of avoidance behaviour, which underlines the need for improving EBT. In rats, recent evidence has highlighted the relevance of the temporal distribution of extinction sessions in reducing SR of auditory fear conditioning, although it has seldom been studied in procedures involving proactive avoidance responses, such as two-way active avoidance conditioning (TWAA). We examined whether the temporal distribution of two extinction sessions separated by 24h or 7days (contiguous versus spaced extinction paradigms, respectively), influences SR after 28days of a TWAA task. c-Fos expression, as a marker of neuronal activation, was also measured by immunohistochemistry 90min after the SR test in the amygdala and the medial prefrontal cortex. The temporal distribution of extinction sessions did not affect the degree of extinction learning. However, only the rats that underwent the 7-day spaced extinction paradigm maintained the level of extinction in the long term, showing no SR in TWAA. This behavioural finding was consistent with a greater number of c-Fos-labelled neurons in the infralimbic cortex in the 7-day group, and in the Lateral and Central nuclei of the amygdala in the 24-hour group. These findings show that a time-spaced extinction paradigm reduces the spontaneous recovery of active avoidance behaviour, and that this behavioural advantage appears to be related to the activation of the infralimbic cortex. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessing Mongolian gerbil emotional behavior: effects of two shock intensities and response-independent shocks during an extended inhibitory-avoidance task.

PubMed

Hurtado-Parrado, Camilo; González-León, Camilo; Arias-Higuera, Mónica A; Cardona, Angelo; Medina, Lucia G; García-Muñoz, Laura; Sánchez, Christian; Cifuentes, Julián; Forigua, Juan Carlos; Ortiz, Andrea; Acevedo-Triana, Cesar A; Rico, Javier L

2017-01-01

performance, extinction, and reacquisition of avoidance behavior in gerbils, which could be easily implemented in a commercially available system. The observation that 1.0 mA shocks produced a clear and consistent avoidance behavior suggests that implementation of higher intensities is unnecessary for reproducing aversive-conditioning effects in this species. The observed patterning of freezing, platform descents, and exploratory responses produced by the change from random to periodic shocks may relate to the active defensive system of the gerbil. Of special interest is the probing behavior, which could be interpreted as risk assessment and has not been reported in other rodent species exposed to step-down and similar tasks.

Assessing Mongolian gerbil emotional behavior: effects of two shock intensities and response-independent shocks during an extended inhibitory-avoidance task

PubMed Central

González-León, Camilo; Arias-Higuera, Mónica A.; Cardona, Angelo; Medina, Lucia G.; García-Muñoz, Laura; Sánchez, Christian; Cifuentes, Julián; Forigua, Juan Carlos; Ortiz, Andrea; Acevedo-Triana, Cesar A.; Rico, Javier L.

2017-01-01

studying steady performance, extinction, and reacquisition of avoidance behavior in gerbils, which could be easily implemented in a commercially available system. The observation that 1.0 mA shocks produced a clear and consistent avoidance behavior suggests that implementation of higher intensities is unnecessary for reproducing aversive-conditioning effects in this species. The observed patterning of freezing, platform descents, and exploratory responses produced by the change from random to periodic shocks may relate to the active defensive system of the gerbil. Of special interest is the probing behavior, which could be interpreted as risk assessment and has not been reported in other rodent species exposed to step-down and similar tasks. PMID:29152417

Functional Connectivity in Frequency-Tagged Cortical Networks During Active Harm Avoidance

PubMed Central

Miskovic, Vladimir; Príncipe, José C.; Keil, Andreas

2015-01-01

Abstract Many behavioral and cognitive processes are grounded in widespread and dynamic communication between brain regions. Thus, the quantification of functional connectivity with high temporal resolution is highly desirable for capturing in vivo brain function. However, many of the commonly used measures of functional connectivity capture only linear signal dependence and are based entirely on relatively simple quantitative measures such as mean and variance. In this study, the authors used a recently developed algorithm, the generalized measure of association (GMA), to quantify dynamic changes in cortical connectivity using steady-state visual evoked potentials (ssVEPs) measured in the context of a conditioned behavioral avoidance task. GMA uses a nonparametric estimator of statistical dependence based on ranks that are efficient and capable of providing temporal precision roughly corresponding to the timing of cognitive acts (∼100–200 msec). Participants viewed simple gratings predicting the presence/absence of an aversive loud noise, co-occurring with peripheral cues indicating whether the loud noise could be avoided by means of a key press (active) or not (passive). For active compared with passive trials, heightened connectivity between visual and central areas was observed in time segments preceding and surrounding the avoidance cue. Viewing of the threat stimuli also led to greater initial connectivity between occipital and central regions, followed by heightened local coupling among visual regions surrounding the motor response. Local neural coupling within extended visual regions was sustained throughout major parts of the viewing epoch. These findings are discussed in a framework of flexible synchronization between cortical networks as a function of experience and active sensorimotor coupling. PMID:25557925

Youth with substance abuse histories exhibit dysfunctional representation of expected value during a passive avoidance task.

PubMed

White, Stuart F; Tyler, Patrick; Botkin, Mary L; Erway, Anna K; Thornton, Laura C; Kolli, Venkata; Pope, Kayla; Meffert, Harma; Blair, R James

2016-11-30

Individuals with substance abuse (SA) histories show impairment in the computations necessary for decision-making, including expected value (EV) and prediction error (PE). Neuroimaging findings, however, have been inconsistent. Sixteen youth with (SA positive ) and 29 youth without (SA negative ) substance abuse histories completed a passive avoidance task while undergoing functional MRI. The groups did not significantly differ on age, gender composition or IQ. Behavioral results indicated that SA positive youth showed significantly less learning than SA negative youth over the task. SA positive youth show problems representing EV information when attempting to avoid sub-optimal choices in bilateral inferior frontal gyrus and striatum. Furthermore, SA positive youth showed a significantly increased differential response to reward versus punishment feedback modulated by PE in posterior cingulate cortex relative to SA negative youth. Disrupted decision-making is likely to exacerbate SA as a failure to represent EV during the avoidance of sub-optimal choices is likely to increase the likelihood of SA. With respect to the representation of PE, future work will be needed to clarify the impact of different substances on the neural systems underpinning PE representation. Moreover, interaction of age/development and substance abuse on PE signaling will need to be explored. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

A Bayesian hierarchical diffusion model decomposition of performance in Approach–Avoidance Tasks

PubMed Central

Krypotos, Angelos-Miltiadis; Beckers, Tom; Kindt, Merel; Wagenmakers, Eric-Jan

2015-01-01

Common methods for analysing response time (RT) tasks, frequently used across different disciplines of psychology, suffer from a number of limitations such as the failure to directly measure the underlying latent processes of interest and the inability to take into account the uncertainty associated with each individual's point estimate of performance. Here, we discuss a Bayesian hierarchical diffusion model and apply it to RT data. This model allows researchers to decompose performance into meaningful psychological processes and to account optimally for individual differences and commonalities, even with relatively sparse data. We highlight the advantages of the Bayesian hierarchical diffusion model decomposition by applying it to performance on Approach–Avoidance Tasks, widely used in the emotion and psychopathology literature. Model fits for two experimental data-sets demonstrate that the model performs well. The Bayesian hierarchical diffusion model overcomes important limitations of current analysis procedures and provides deeper insight in latent psychological processes of interest. PMID:25491372

Who multi-tasks and why? Multi-tasking ability, perceived multi-tasking ability, impulsivity, and sensation seeking.

PubMed

Sanbonmatsu, David M; Strayer, David L; Medeiros-Ward, Nathan; Watson, Jason M

2013-01-01

The present study examined the relationship between personality and individual differences in multi-tasking ability. Participants enrolled at the University of Utah completed measures of multi-tasking activity, perceived multi-tasking ability, impulsivity, and sensation seeking. In addition, they performed the Operation Span in order to assess their executive control and actual multi-tasking ability. The findings indicate that the persons who are most capable of multi-tasking effectively are not the persons who are most likely to engage in multiple tasks simultaneously. To the contrary, multi-tasking activity as measured by the Media Multitasking Inventory and self-reported cell phone usage while driving were negatively correlated with actual multi-tasking ability. Multi-tasking was positively correlated with participants' perceived ability to multi-task ability which was found to be significantly inflated. Participants with a strong approach orientation and a weak avoidance orientation--high levels of impulsivity and sensation seeking--reported greater multi-tasking behavior. Finally, the findings suggest that people often engage in multi-tasking because they are less able to block out distractions and focus on a singular task. Participants with less executive control--low scorers on the Operation Span task and persons high in impulsivity--tended to report higher levels of multi-tasking activity.

Central ghrelin increases anxiety in the Open Field test and impairs retention memory in a passive avoidance task in neonatal chicks.

PubMed

Carvajal, Pedro; Carlini, Valeria P; Schiöth, Helgi B; de Barioglio, Susana R; Salvatierra, Nancy A

2009-05-01

Ghrelin (Grh) is an endogenous ligand for the growth hormone secretagogue receptor. Although Ghr stimulates feeding in rats, it inhibits feeding in neonatal chicks. However, little is known about other central behavioral effects of Ghr. Therefore, we investigated the Ghr effects, injected intracerebroventricularly, on anxiety and memory retention of neonatal chicks in an Open Field test and in a one-trial passive avoidance task, respectively. In the Open Field test, the administration of Ghr in a dose-dependent manner increased the latency to ambulate but decreased ambulation activity, indicating an anxiogenic effect. Furthermore, chicks trained on a passive avoidance task and injected with a dose of 30pmol of Ghr immediately after training showed an impairment of memory retention. However, there were no significant effects on the number of pecks during the pretraining, training, retention and discrimination. In addition, different doses of Ghr produced an inhibition in food intake at different times after injection. Our results indicate that Ghr induces anxiogenesis in chicks. Moreover, we have shown for the first time that Ghr can decrease memory retention in a non-mammalian species, suggesting that Ghr may play an important role in the processes of memory retention in birds.

Activity flow over resting-state networks shapes cognitive task activations.

PubMed

Cole, Michael W; Ito, Takuya; Bassett, Danielle S; Schultz, Douglas H

2016-12-01

Resting-state functional connectivity (FC) has helped reveal the intrinsic network organization of the human brain, yet its relevance to cognitive task activations has been unclear. Uncertainty remains despite evidence that resting-state FC patterns are highly similar to cognitive task activation patterns. Identifying the distributed processes that shape localized cognitive task activations may help reveal why resting-state FC is so strongly related to cognitive task activations. We found that estimating task-evoked activity flow (the spread of activation amplitudes) over resting-state FC networks allowed prediction of cognitive task activations in a large-scale neural network model. Applying this insight to empirical functional MRI data, we found that cognitive task activations can be predicted in held-out brain regions (and held-out individuals) via estimated activity flow over resting-state FC networks. This suggests that task-evoked activity flow over intrinsic networks is a large-scale mechanism explaining the relevance of resting-state FC to cognitive task activations.

Activity flow over resting-state networks shapes cognitive task activations

PubMed Central

Cole, Michael W.; Ito, Takuya; Bassett, Danielle S.; Schultz, Douglas H.

2016-01-01

Resting-state functional connectivity (FC) has helped reveal the intrinsic network organization of the human brain, yet its relevance to cognitive task activations has been unclear. Uncertainty remains despite evidence that resting-state FC patterns are highly similar to cognitive task activation patterns. Identifying the distributed processes that shape localized cognitive task activations may help reveal why resting-state FC is so strongly related to cognitive task activations. We found that estimating task-evoked activity flow (the spread of activation amplitudes) over resting-state FC networks allows prediction of cognitive task activations in a large-scale neural network model. Applying this insight to empirical functional MRI data, we found that cognitive task activations can be predicted in held-out brain regions (and held-out individuals) via estimated activity flow over resting-state FC networks. This suggests that task-evoked activity flow over intrinsic networks is a large-scale mechanism explaining the relevance of resting-state FC to cognitive task activations. PMID:27723746

Echolocation behaviour of the big brown bat (Eptesicus fuscus) in an obstacle avoidance task of increasing difficulty.

PubMed

Sändig, Sonja; Schnitzler, Hans-Ulrich; Denzinger, Annette

2014-08-15

Four big brown bats (Eptesicus fuscus) were challenged in an obstacle avoidance experiment to localize vertically stretched wires requiring progressively greater accuracy by diminishing the wire-to-wire distance from 50 to 10 cm. The performance of the bats decreased with decreasing gap size. The avoidance task became very difficult below a wire separation of 30 cm, which corresponds to the average wingspan of E. fuscus. Two of the bats were able to pass without collisions down to a gap size of 10 cm in some of the flights. The other two bats only managed to master gap sizes down to 20 and 30 cm, respectively. They also performed distinctly worse at all other gap sizes. With increasing difficulty of the task, the bats changed their flight and echolocation behaviour. Especially at gap sizes of 30 cm and below, flight paths increased in height and flight speed was reduced. In addition, the bats emitted approach signals that were arranged in groups. At all gap sizes, the largest numbers of pulses per group were observed in the last group before passing the obstacle. The more difficult the obstacle avoidance task, the more pulses there were in the groups and the shorter the within-group pulse intervals. In comparable situations, the better-performing bats always emitted groups with more pulses than the less well-performing individuals. We hypothesize that the accuracy of target localization increases with the number of pulses per group and that each group is processed as a package. © 2014. Published by The Company of Biologists Ltd.

Active Collision Avoidance for Planetary Landers

NASA Technical Reports Server (NTRS)

Rickman, Doug; Hannan, Mike; Srinivasan, Karthik

2014-01-01

Present day robotic missions to other planets require precise, a priori knowledge of the terrain to pre-determine a landing spot that is safe. Landing sites can be miles from the mission objective, or, mission objectives may be tailored to suit landing sites. Future robotic exploration missions should be capable of autonomously identifying a safe landing target within a specified target area selected by mission requirements. Such autonomous landing sites must (1) 'see' the surface, (2) identify a target, and (3) land the vehicle. Recent advances in radar technology have resulted in small, lightweight, low power radars that are used for collision avoidance and cruise control systems in automobiles. Such radar systems can be adapted for use as active hazard avoidance systems for planetary landers. The focus of this CIF proposal is to leverage earlier work on collision avoidance systems for MSFC's Mighty Eagle lander and evaluate the use of automotive radar systems for collision avoidance in planetary landers.

Discrimination and avoidance learning in adult mice following developmental exposure to diisopropylfluorophosphate.

PubMed

Levi, Yifat; Kofman, Ora; Schwebel, Margalit; Shaldubina, Alona

2008-02-01

Exposure to acetylcholinesterase inhibitors during development was shown in the past to induce sex-dependent changes in locomotion and specific cognitive and emotional tests in rodents. Adult mice that had been treated with 0.5 mg/kg diisopropylfluorphosphate (DFP), on post-natal days 14-20 were tested on active avoidance and a set-shifting task. DFP pre-treatment did not affect the active avoidance task, but impaired performance on the extra-dimensional shift task. DFP-treated females showed more general deficits in the acquisition of simple discrimination, intra-dimensional shift, extra-dimensional shift and reversal learning. These data suggest that pre-weanling exposure to cholinesterase inhibitors may have long-term consequences on attentional capabilities.

Individual variation in the neural processes of motor decisions in the stop signal task: the influence of novelty seeking and harm avoidance personality traits.

PubMed

Hu, Jianping; Lee, Dianne; Hu, Sien; Zhang, Sheng; Chao, Herta; Li, Chiang-Shan R

2016-06-01

Personality traits contribute to variation in human behavior, including the propensity to take risk. Extant work targeted risk-taking processes with an explicit manipulation of reward, but it remains unclear whether personality traits influence simple decisions such as speeded versus delayed responses during cognitive control. We explored this issue in an fMRI study of the stop signal task, in which participants varied in response time trial by trial, speeding up and risking a stop error or slowing down to avoid errors. Regional brain activations to speeded versus delayed motor responses (risk-taking) were correlated to novelty seeking (NS), harm avoidance (HA) and reward dependence (RD), with age and gender as covariates, in a whole brain regression. At a corrected threshold, the results showed a positive correlation between NS and risk-taking responses in the dorsomedial prefrontal, bilateral orbitofrontal, and frontopolar cortex, and between HA and risk-taking responses in the parahippocampal gyrus and putamen. No regional activations varied with RD. These findings demonstrate that personality traits influence the neural processes of executive control beyond behavioral tasks that involve explicit monetary reward. The results also speak broadly to the importance of characterizing inter-subject variation in studies of cognition and brain functions.

Additive effect of harmane and muscimol for memory consolidation impairment in inhibitory avoidance task.

PubMed

Nasehi, Mohammad; Morteza-Zadeh, Parastoo; Khakpai, Fatemeh; Zarrindast, Mohammad-Reza

2016-12-17

In the current study, we examined the effect of bilateral intra-dorsal hippocampal (intra-CA1) microinjections of GABA A receptor agents on amnesia induced by a β-carboline alkaloid, harmane in mice. We used a single-trial step-down passive avoidance task to assess memory retention and then, open-field test to assess locomotor activity. The results indicated that post-training intra-CA1 injections of bicuculline - a GABA A receptor antagonist - had no significant effect, while muscimol (0.01 and 0.1μg/mouse) - a GABA A receptor agonist - impaired memory consolidation. Post-training intra-peritoneal (i.p.) infusion of harmane (3 and 5mg/kg) decreased memory consolidation. Furthermore, post-training intra-CA1 administration of sub-threshold dose of bicuculline (0.001μg/mouse) restored, whereas muscimol (0.001μg/mouse) potentiated impairment of memory consolidation induced by harmane. The isobologram analysis revealed that there is an additive effect between harmane and muscimol on impairment of memory consolidation. Moreover, all above doses of drugs did not alter locomotor activity. These findings suggest that GABA A receptors of the CA1 area, at least partly, play a role in modulating the effect of harmane on memory consolidation. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Are the carrot and the stick the two sides of same coin? A neural examination of approach/avoidance motivation during cognitive performance.

PubMed

Belayachi, Sanaâ; Majerus, Steve; Gendolla, Guido; Salmon, Eric; Peters, Frédéric; Van der Linden, Martial

2015-10-15

The present study examined neural circuit activity in a working memory (WM) task under conditions of approach and avoidance motivation. Eighteen participants were scanned with functional MRI while they performed a 3-back WM task under three conditions: in an avoidance condition incorrect responses were punished with monetary loss; in an approach condition correct responses were rewarded with monetary gain; in a neutral control condition there was no monetary incentive. Compared with the control condition, activation in fronto-parietal areas - which are associated with WM processing - was increased in both the approach and avoidance conditions. The results suggest that both approach and avoidance motivation increase task-related cognitive activation. Copyright © 2015 Elsevier B.V. All rights reserved.

Selective attention and avoidance on a pictorial cueing task during stress in clinically anxious and depressed participants.

PubMed

Ellenbogen, Mark A; Schwartzman, Alex E

2009-02-01

Although it is well established that attentional biases exist in anxious populations, the specific components of visual orienting towards and away from emotional stimuli are not well delineated. The present study was designed to examine these processes. We used a modified spatial cueing task to assess the speed of engagement and disengagement from supraliminal and masked pictorial cues depicting threat, dysphoria, or neutral content in 36 clinically anxious, 41 depressed and 41 control participants. Participants were randomly assigned to a stress or neutral condition. During stress, anxious participants were slow to disengage from masked left hemifield pictures depicting threat or dysphoria, but were quick to disengage from supraliminal threat pictures. Information processing in anxious participants during stress was characterized by early selective attention of emotional stimuli, occurring prior to full conscious awareness, followed by effortful avoidance of threat. Depressed participants were distinct from the anxious group, displaying selective attention for stimuli depicting dysphoria, but not threat, during the neutral condition. In sum, attentional biases in clinical populations are associated with difficulties in the disengagement component of visual orienting. Further, a vigilant-avoidant pattern of attentional bias may represent a strategic attempt to compensate for the early activation of a fear response.

Active Avoidance: Neural Mechanisms and Attenuation of Pavlovian Conditioned Responding.

PubMed

Boeke, Emily A; Moscarello, Justin M; LeDoux, Joseph E; Phelps, Elizabeth A; Hartley, Catherine A

2017-05-03

Patients with anxiety disorders often experience a relapse in symptoms after exposure therapy. Similarly, threat responses acquired during Pavlovian threat conditioning often return after extinction learning. Accordingly, there is a need for alternative methods to persistently reduce threat responding. Studies in rodents have suggested that exercising behavioral control over an aversive stimulus can persistently diminish threat responses, and that these effects are mediated by the amygdala, ventromedial prefrontal cortex, and striatum. In this fMRI study, we attempted to translate these findings to humans. Subjects first underwent threat conditioning. We then contrasted two forms of safety learning: active avoidance, in which participants could prevent the shock through an action, and yoked extinction, with shock presentation matched to the active condition, but without instrumental control. The following day, we assessed subjects' threat responses (measured by skin conductance) to the conditioned stimuli without shock. Subjects next underwent threat conditioning with novel stimuli. Yoked extinction subjects showed an increase in conditioned response to stimuli from the previous day, but the active avoidance group did not. Additionally, active avoidance subjects showed reduced conditioned responding during novel threat conditioning, but the extinction group did not. We observed between-group differences in striatal BOLD responses to shock omission in Avoidance/Extinction. These findings suggest a differential role for the striatum in human active avoidance versus extinction learning, and indicate that active avoidance may be more effective than extinction in persistently diminishing threat responses. SIGNIFICANCE STATEMENT Extinguished threat responses often reemerge with time, highlighting the importance of identifying more enduring means of attenuation. We compared the effects of active avoidance learning and yoked extinction on threat responses in humans and

Active Avoidance: Neural Mechanisms and Attenuation of Pavlovian Conditioned Responding

PubMed Central

Boeke, Emily A.; Moscarello, Justin M.; Phelps, Elizabeth A.

2017-01-01

Patients with anxiety disorders often experience a relapse in symptoms after exposure therapy. Similarly, threat responses acquired during Pavlovian threat conditioning often return after extinction learning. Accordingly, there is a need for alternative methods to persistently reduce threat responding. Studies in rodents have suggested that exercising behavioral control over an aversive stimulus can persistently diminish threat responses, and that these effects are mediated by the amygdala, ventromedial prefrontal cortex, and striatum. In this fMRI study, we attempted to translate these findings to humans. Subjects first underwent threat conditioning. We then contrasted two forms of safety learning: active avoidance, in which participants could prevent the shock through an action, and yoked extinction, with shock presentation matched to the active condition, but without instrumental control. The following day, we assessed subjects' threat responses (measured by skin conductance) to the conditioned stimuli without shock. Subjects next underwent threat conditioning with novel stimuli. Yoked extinction subjects showed an increase in conditioned response to stimuli from the previous day, but the active avoidance group did not. Additionally, active avoidance subjects showed reduced conditioned responding during novel threat conditioning, but the extinction group did not. We observed between-group differences in striatal BOLD responses to shock omission in Avoidance/Extinction. These findings suggest a differential role for the striatum in human active avoidance versus extinction learning, and indicate that active avoidance may be more effective than extinction in persistently diminishing threat responses. SIGNIFICANCE STATEMENT Extinguished threat responses often reemerge with time, highlighting the importance of identifying more enduring means of attenuation. We compared the effects of active avoidance learning and yoked extinction on threat responses in humans and

Brain activations during bimodal dual tasks depend on the nature and combination of component tasks

PubMed Central

Salo, Emma; Rinne, Teemu; Salonen, Oili; Alho, Kimmo

2015-01-01

We used functional magnetic resonance imaging to investigate brain activations during nine different dual tasks in which the participants were required to simultaneously attend to concurrent streams of spoken syllables and written letters. They performed a phonological, spatial or “simple” (speaker-gender or font-shade) discrimination task within each modality. We expected to find activations associated specifically with dual tasking especially in the frontal and parietal cortices. However, no brain areas showed systematic dual task enhancements common for all dual tasks. Further analysis revealed that dual tasks including component tasks that were according to Baddeley's model “modality atypical,” that is, the auditory spatial task or the visual phonological task, were not associated with enhanced frontal activity. In contrast, for other dual tasks, activity specifically associated with dual tasking was found in the left or bilateral frontal cortices. Enhanced activation in parietal areas, however, appeared not to be specifically associated with dual tasking per se, but rather with intermodal attention switching. We also expected effects of dual tasking in left frontal supramodal phonological processing areas when both component tasks required phonological processing and in right parietal supramodal spatial processing areas when both tasks required spatial processing. However, no such effects were found during these dual tasks compared with their component tasks performed separately. Taken together, the current results indicate that activations during dual tasks depend in a complex manner on specific demands of component tasks. PMID:25767443

A New Paradigm for Evaluating Avoidance/Escape Motivation.

PubMed

Tsutsui-Kimura, Iku; Bouchekioua, Youcef; Mimura, Masaru; Tanaka, Kenji F

2017-07-01

Organisms have evolved to approach pleasurable opportunities and to avoid or escape from aversive experiences. These 2 distinct motivations are referred to as approach and avoidance/escape motivations and are both considered vital for survival. Despite several recent advances in understanding the neurobiology of motivation, most studies addressed approach but not avoidance/escape motivation. Here we develop a new experimental paradigm to quantify avoidance/escape motivation and examine the pharmacological validity. We set up an avoidance variable ratio 5 task in which mice were required to press a lever for variable times to avoid an upcoming aversive stimulus (foot shock) or to escape the ongoing aversive event if they failed to avoid it. We i.p. injected ketamine (0, 1, or 5 mg/kg) or buspirone (0, 5, or 10 mg/kg) 20 or 30 minutes before the behavioral task to see if ketamine enhanced avoidance/escape behavior and buspirone diminished it as previously reported. We found that the performance on the avoidance variable ratio 5 task was sensitive to the intensity of the aversive stimulus. Treatment with ketamine increased while that with buspirone decreased the probability of avoidance from an aversive stimulus in the variable ratio 5 task, being consistent with previous reports. Our new paradigm will prove useful for quantifying avoidance/escape motivation and will contribute to a more comprehensive understanding of motivation. © The Author 2017. Published by Oxford University Press on behalf of CINP.

The prepared emotional reflex: intentional preparation of automatic approach and avoidance tendencies as a means to regulate emotional responding.

PubMed

Eder, Andreas B; Rothermund, Klaus; Proctor, Robert W

2010-08-01

Advance preparation of action courses toward emotional stimuli is an effective means to regulate impulsive emotional behavior. Our experiment shows that performing intentional acts of approach and avoidance in an evaluation task influences the unintended activation of approach and avoidance tendencies in another task in which stimulus valence is irrelevant. For the evaluation-relevant blocks, participants received either congruent (positive-approach, negative-avoidance) or incongruent (positive-avoidance, negative-approach) mapping instructions. In the evaluation-irrelevant blocks, approach- and avoidance-related lever movements were selected in response to a stimulus feature other than valence (affective Simon task). Response mapping in the evaluation task influenced performance in the evaluation-irrelevant task: An enhanced affective Simon effect was observed with congruent mapping instructions; in contrast, the effect was reversed when the evaluation task required incongruent responses. Thus, action instructions toward affective stimuli received in one task determined affective response tendencies in another task where these instructions were not in effect. These findings suggest that intentionally prepared short-term links between affective valence and motor responses elicit associated responses without a deliberate act of will, operating like a "prepared reflex." Copyright 2010 APA

Neural Mechanisms for Adaptive Learned Avoidance of Mental Effort.

PubMed

Mitsuto Nagase, Asako; Onoda, Keiichi; Clifford Foo, Jerome; Haji, Tomoki; Akaishi, Rei; Yamaguchi, Shuhei; Sakai, Katsuyuki; Morita, Kenji

2018-02-05

Humans tend to avoid mental effort. Previous studies have demonstrated this tendency using various demand-selection tasks; participants generally avoid options associated with higher cognitive demand. However, it remains unclear whether humans avoid mental effort adaptively in uncertain and non-stationary environments, and if so, what neural mechanisms underlie this learned avoidance and whether they remain the same irrespective of cognitive-demand types. We addressed these issues by developing novel demand-selection tasks where associations between choice options and cognitive-demand levels change over time, with two variations using mental arithmetic and spatial reasoning problems (29:4 and 18:2 males:females). Most participants showed avoidance, and their choices depended on the demand experienced on multiple preceding trials. We assumed that participants updated the expected cost of mental effort through experience, and fitted their choices by reinforcement learning models, comparing several possibilities. Model-based fMRI analyses revealed that activity in the dorsomedial and lateral frontal cortices was positively correlated with the trial-by-trial expected cost for the chosen option commonly across the different types of cognitive demand, and also revealed a trend of negative correlation in the ventromedial prefrontal cortex. We further identified correlates of cost-prediction-error at time of problem-presentation or answering the problem, the latter of which partially overlapped with or were proximal to the correlates of expected cost at time of choice-cue in the dorsomedial frontal cortex. These results suggest that humans adaptively learn to avoid mental effort, having neural mechanisms to represent expected cost and cost-prediction-error, and the same mechanisms operate for various types of cognitive demand. SIGNIFICANCE STATEMENT In daily life, humans encounter various cognitive demands, and tend to avoid high-demand options. However, it remains unclear

Blink activity and task difficulty.

PubMed

Tanaka, Y; Yamaoka, K

1993-08-01

This study investigated the relationship between task difficulty and blink activity, which includes blink rate, blink amplitude, and blink duration. Two kinds of tasks established two levels of difficulty. In Exp. 1, a mental arithmetic task was used to examine the relationship. Analysis showed that blink rate for a difficult task was significantly higher than that for an easier one. In Exp. 2, a letter-search task (hiragana Japanese alphabet) was used while the other conditions were the same as those in Exp. 1; however, the results of this experiment were not influenced by the difficulty of the task. As results indicate that blink rate is related to not only difficulty but also the nature of the task, the nature of the task is probably dependent on a mechanism in information processing. The results for blink amplitude and blink duration showed no systematic change during either experiment.

Exaggerated acquisition and resistance to extinction of avoidance behavior in treated heroin-dependent men.

PubMed

Sheynin, Jony; Moustafa, Ahmed A; Beck, Kevin D; Servatius, Richard J; Casbolt, Peter A; Haber, Paul; Elsayed, Mahmoud; Hogarth, Lee; Myers, Catherine E

2016-03-01

Addiction is often conceptualized as a behavioral strategy for avoiding negative experiences. In rodents, opioid intake has been associated with abnormal acquisition and extinction of avoidance behavior. Here, we tested the hypothesis that these findings would generalize to human opioid-dependent subjects. Adults meeting DSM-IV criteria for heroin dependence and treated with opioid medication (n = 27) and healthy controls (n = 26) were recruited between March 2013 and October 2013 and given a computer-based task to assess avoidance behavior. For this task, subjects controlled a spaceship and could either gain points by shooting an enemy spaceship or hide in safe areas to avoid on-screen aversive events. Hiding duration during different periods of the task was used to measure avoidance behavior. While groups did not differ on escape responding (hiding) during the aversive event, heroin-dependent men (but not women) made more avoidance responses during a warning signal that predicted the aversive event (analysis of variance, sex × group interaction, P = .007). Heroin-dependent men were also slower to extinguish the avoidance response when the aversive event no longer followed the warning signal (P = .011). This behavioral pattern resulted in reduced opportunity to obtain reward without reducing risk of punishment. Results suggest that, in male patients, differences in avoidance behavior cannot be easily explained by impaired task performance or by exaggerated motor activity. This study provides evidence for abnormal acquisition and extinction of avoidance behavior in opioid-dependent patients. Interestingly, data suggest that abnormal avoidance is demonstrated only by male patients. Findings shed light on cognitive and behavioral manifestations of opioid addiction and may facilitate development of therapeutic approaches to help affected individuals. © Copyright 2016 Physicians Postgraduate Press, Inc.

Task difficulty modulates brain activation in the emotional oddball task.

PubMed

Siciliano, Rachel E; Madden, David J; Tallman, Catherine W; Boylan, Maria A; Kirste, Imke; Monge, Zachary A; Packard, Lauren E; Potter, Guy G; Wang, Lihong

2017-06-01

Previous functional magnetic resonance imaging (fMRI) studies have reported that task-irrelevant, emotionally salient events can disrupt target discrimination, particularly when attentional demands are low, while others demonstrate alterations in the distracting effects of emotion in behavior and neural activation in the context of attention-demanding tasks. We used fMRI, in conjunction with an emotional oddball task, at different levels of target discrimination difficulty, to investigate the effects of emotional distractors on the detection of subsequent targets. In addition, we distinguished different behavioral components of target detection representing decisional, nondecisional, and response criterion processes. Results indicated that increasing target discrimination difficulty led to increased time required for both the decisional and nondecisional components of the detection response, as well as to increased target-related neural activation in frontoparietal regions. The emotional distractors were associated with activation in ventral occipital and frontal regions and dorsal frontal regions, but this activation was attenuated with increased difficulty. Emotional distraction did not alter the behavioral measures of target detection, but did lead to increased target-related frontoparietal activation for targets following emotional images as compared to those following neutral images. This latter effect varied with target discrimination difficulty, with an increased influence of the emotional distractors on subsequent target-related frontoparietal activation in the more difficult discrimination condition. This influence of emotional distraction was in addition associated specifically with the decisional component of target detection. These findings indicate that emotion-cognition interactions, in the emotional oddball task, vary depending on the difficulty of the target discrimination and the associated limitations on processing resources. Copyright © 2017

Amygdala task-evoked activity and task-free connectivity independently contribute to feelings of arousal.

PubMed

Touroutoglou, Alexandra; Bickart, Kevin C; Barrett, Lisa Feldman; Dickerson, Bradford C

2014-10-01

Individual differences in the intensity of feelings of arousal while viewing emotional pictures have been associated with the magnitude of task-evoked blood-oxygen dependent (BOLD) response in the amygdala. Recently, we reported that individual differences in feelings of arousal are associated with task-free (resting state) connectivity within the salience network. There has not yet been an investigation of whether these two types of functional magnetic resonance imaging (MRI) measures are redundant or independent in their relationships to behavior. Here we tested the hypothesis that a combination of task-evoked amygdala activation and task-free amygdala connectivity within the salience network relate to individual differences in feelings of arousal while viewing of negatively potent images. In 25 young adults, results revealed that greater task-evoked amygdala activation and stronger task-free amygdala connectivity within the salience network each contributed independently to feelings of arousal, predicting a total of 45% of its variance. Individuals who had both increased task-evoked amygdala activation and stronger task-free amygdala connectivity within the salience network had the most heightened levels of arousal. Task-evoked amygdala activation and task-free amygdala connectivity within the salience network were not related to each other, suggesting that resting-state and task-evoked dynamic brain imaging measures may provide independent and complementary information about affective experience, and likely other kinds of behaviors as well. Copyright © 2014 Wiley Periodicals, Inc.

Psychopaths lack the automatic avoidance of social threat: relation to instrumental aggression.

PubMed

Louise von Borries, Anna Katinka; Volman, Inge; de Bruijn, Ellen Rosalia Aloïs; Bulten, Berend Hendrik; Verkes, Robbert Jan; Roelofs, Karin

2012-12-30

Psychopathy (PP) is associated with marked abnormalities in social emotional behaviour, such as high instrumental aggression (IA). A crucial but largely ignored question is whether automatic social approach-avoidance tendencies may underlie this condition. We tested whether offenders with PP show lack of automatic avoidance tendencies, usually activated when (healthy) individuals are confronted with social threat stimuli (angry faces). We applied a computerized approach-avoidance task (AAT), where participants pushed or pulled pictures of emotional faces using a joystick, upon which the faces decreased or increased in size, respectively. Furthermore, participants completed an emotion recognition task which was used to control for differences in recognition of facial emotions. In contrast to healthy controls (HC), PP patients showed total absence of avoidance tendencies towards angry faces. Interestingly, those responses were related to levels of instrumental aggression and the (in)ability to experience personal distress (PD). These findings suggest that social performance in psychopaths is disturbed on a basic level of automatic action tendencies. The lack of implicit threat avoidance tendencies may underlie their aggressive behaviour. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Maintain and Regain Well Clear: Maneuver Guidance Designs for Pilots Performing the Detect-and-Avoid Task

NASA Technical Reports Server (NTRS)

Monk, Kevin J.; Roberts, Zachary

2017-01-01

In order to support the future expansion and integration of Unmanned Aircraft Systems (UAS), ongoing research efforts have sought to produce findings that inform the minimum display information elements required for acceptable UAS pilot response times and traffic avoidance. Previous simulations have revealed performance benefits associated with DAA displays containing predictive information and suggestive maneuver guidance tools in the form of banding. The present study investigated the impact of various maneuver guidance display configurations on detect-and-avoid (DAA) task performance in a simulated airspace environment. UAS pilots ability to maintain DAA well clear was compared between displays with either the presence or absence of green DAA bands, which indicated conflict-free flight regions. Additional display comparisons assessed pilots ability to regain DAA well clear with two different guidance presentations designed to aid in DAA well clear recovery during critical encounters. Performance implications and display considerations for future UAS DAA systems are discussed.

Reduction in Memory Specificity Following an Approach/Avoidance Scrambled Sentences Task Relates to Cognitive Avoidant Coping

ERIC Educational Resources Information Center

Debeer, Elise; Raes, Filip; Williams, J. Mark G.; Hermans, Dirk

2013-01-01

"Overgeneral autobiographical memory" (OGM) refers to the tendency to retrieve less specific personal memories. According to the functional avoidance hypothesis, OGM might act as a cognitive strategy to avoid emotionally distressing details of negative memories. In the present study, we investigated the effect of an experimentally…

Response inhibition predicts painful task duration and performance in healthy individuals performing a cold pressor task in a motivational context.

PubMed

Karsdorp, P A; Geenen, R; Vlaeyen, J W S

2014-01-01

Long-term avoidance of painful activities has shown to be dysfunctional in chronic pain. Pain may elicit escape or avoidance responses automatically, particularly when pain-related fear is high. A conflict may arise between opposing short-term escape/avoidance goals to reduce pain and long-term approach goals to receive a reward. An inhibitory control system may resolve this conflict. It was hypothesized that reduced response inhibition would be associated with greater escape/avoidance during pain, particularly among subjects with higher pain-related fear. Response inhibition was measured with the stop-signal task, and pain-related fear with the Fear of Pain Questionnaire. Participants completed a tone-detection task (TDT) in which they could earn money while being exposed to cold pressor pain. Escape/avoidance was operationalized as the hand immersion time during a cold pressor task (CPT) and the performance on the TDT. Poorer response inhibition was associated with shorter CPT immersion duration and with worse TDT performance. Pain after the CPT was associated with pain-related fear, but not with response inhibition. No supportive evidence was found for the hypothesis that the relation between inhibition and escape/avoidance would be most pronounced for those with higher pain-related fear. In contrast, the relation between response inhibition and number of hits on the TDT was most pronounced for those with lower pain-related fear. The findings suggest that individuals with a stronger ability to inhibit responses in a stop-signal task are better able to inhibit escape/avoidance responses elicited by pain, in the service of a conflicting approach goal. © 2013 European Pain Federation - EFIC®

Anterior medial prefrontal cortex exhibits activation during task preparation but deactivation during task execution.

PubMed

Koshino, Hideya; Minamoto, Takehiro; Ikeda, Takashi; Osaka, Mariko; Otsuka, Yuki; Osaka, Naoyuki

2011-01-01

The anterior prefrontal cortex (PFC) exhibits activation during some cognitive tasks, including episodic memory, reasoning, attention, multitasking, task sets, decision making, mentalizing, and processing of self-referenced information. However, the medial part of anterior PFC is part of the default mode network (DMN), which shows deactivation during various goal-directed cognitive tasks compared to a resting baseline. One possible factor for this pattern is that activity in the anterior medial PFC (MPFC) is affected by dynamic allocation of attentional resources depending on task demands. We investigated this possibility using an event related fMRI with a face working memory task. Sixteen students participated in a single fMRI session. They were asked to form a task set to remember the faces (Face memory condition) or to ignore them (No face memory condition), then they were given 6 seconds of preparation period before the onset of the face stimuli. During this 6-second period, four single digits were presented one at a time at the center of the display, and participants were asked to add them and to remember the final answer. When participants formed a task set to remember faces, the anterior MPFC exhibited activation during a task preparation period but deactivation during a task execution period within a single trial. The results suggest that the anterior MPFC plays a role in task set formation but is not involved in execution of the face working memory task. Therefore, when attentional resources are allocated to other brain regions during task execution, the anterior MPFC shows deactivation. The results suggest that activation and deactivation in the anterior MPFC are affected by dynamic allocation of processing resources across different phases of processing.

Anterior Medial Prefrontal Cortex Exhibits Activation during Task Preparation but Deactivation during Task Execution

PubMed Central

Koshino, Hideya; Minamoto, Takehiro; Ikeda, Takashi; Osaka, Mariko; Otsuka, Yuki; Osaka, Naoyuki

2011-01-01

Background The anterior prefrontal cortex (PFC) exhibits activation during some cognitive tasks, including episodic memory, reasoning, attention, multitasking, task sets, decision making, mentalizing, and processing of self-referenced information. However, the medial part of anterior PFC is part of the default mode network (DMN), which shows deactivation during various goal-directed cognitive tasks compared to a resting baseline. One possible factor for this pattern is that activity in the anterior medial PFC (MPFC) is affected by dynamic allocation of attentional resources depending on task demands. We investigated this possibility using an event related fMRI with a face working memory task. Methodology/Principal Findings Sixteen students participated in a single fMRI session. They were asked to form a task set to remember the faces (Face memory condition) or to ignore them (No face memory condition), then they were given 6 seconds of preparation period before the onset of the face stimuli. During this 6-second period, four single digits were presented one at a time at the center of the display, and participants were asked to add them and to remember the final answer. When participants formed a task set to remember faces, the anterior MPFC exhibited activation during a task preparation period but deactivation during a task execution period within a single trial. Conclusions/Significance The results suggest that the anterior MPFC plays a role in task set formation but is not involved in execution of the face working memory task. Therefore, when attentional resources are allocated to other brain regions during task execution, the anterior MPFC shows deactivation. The results suggest that activation and deactivation in the anterior MPFC are affected by dynamic allocation of processing resources across different phases of processing. PMID:21829668

Exaggerated acquisition and resistance to extinction of avoidance behavior in treated heroin-dependent males

PubMed Central

Sheynin, Jony; Moustafa, Ahmed A.; Beck, Kevin D.; Servatius, Richard J.; Casbolt, Peter A.; Haber, Paul; Elsayed, Mahmoud; Hogarth, Lee; Myers, Catherine E.

2015-01-01

Objective Addiction is often conceptualized as a behavioral strategy for avoiding negative experiences. In rodents, opioid intake has been associated with abnormal acquisition and extinction of avoidance behavior. Here, we tested the hypothesis that these findings would generalize to human opioid-dependent subjects. Method Adults meeting DSM-IV criteria for heroin-dependence and treated with opioid medication (n=27), and healthy controls (n=26), were recruited between March–October 2013 and given a computer-based task to assess avoidance behavior. On this task, subjects controlled a spaceship and could either gain points by shooting an enemy spaceship, or hide in safe areas to avoid on-screen aversive events. Results While groups did not differ on escape responding (hiding) during the aversive event, heroin-dependent males (but not females) made more avoidance responses during a warning signal that predicted the aversive event (ANOVA, sex × group interaction, p=0.007). This group was also slower to extinguish the avoidance response when the aversive event no longer followed the warning signal (p=0.011). This behavioral pattern resulted in reduced opportunity to obtain reward without reducing risk of punishment. Results suggest that differences in avoidance behavior cannot be easily explained by impaired task performance or by exaggerated motor activity in male patients. Conclusion This study provides evidence for abnormal acquisition and extinction of avoidance behavior in opioid-dependent patients. Interestingly, data suggest abnormal avoidance is demonstrated only by male patients. Findings shed light on cognitive and behavioral manifestations of opioid addiction, and may facilitate development of therapeutic approaches to help affected individuals. PMID:27046310

Task-discriminative space-by-time factorization of muscle activity.

PubMed

Delis, Ioannis; Panzeri, Stefano; Pozzo, Thierry; Berret, Bastien

2015-01-01

Movement generation has been hypothesized to rely on a modular organization of muscle activity. Crucial to this hypothesis is the ability to perform reliably a variety of motor tasks by recruiting a limited set of modules and combining them in a task-dependent manner. Thus far, existing algorithms that extract putative modules of muscle activations, such as Non-negative Matrix Factorization (NMF), identify modular decompositions that maximize the reconstruction of the recorded EMG data. Typically, the functional role of the decompositions, i.e., task accomplishment, is only assessed a posteriori. However, as motor actions are defined in task space, we suggest that motor modules should be computed in task space too. In this study, we propose a new module extraction algorithm, named DsNM3F, that uses task information during the module identification process. DsNM3F extends our previous space-by-time decomposition method (the so-called sNM3F algorithm, which could assess task performance only after having computed modules) to identify modules gauging between two complementary objectives: reconstruction of the original data and reliable discrimination of the performed tasks. We show that DsNM3F recovers the task dependence of module activations more accurately than sNM3F. We also apply it to electromyographic signals recorded during performance of a variety of arm pointing tasks and identify spatial and temporal modules of muscle activity that are highly consistent with previous studies. DsNM3F achieves perfect task categorization without significant loss in data approximation when task information is available and generalizes as well as sNM3F when applied to new data. These findings suggest that the space-by-time decomposition of muscle activity finds robust task-discriminating modular representations of muscle activity and that the insertion of task discrimination objectives is useful for describing the task modulation of module recruitment.

The Impact of Suggestive Maneuver Guidance on UAS Pilots Performing the Detect and Avoid Function

NASA Technical Reports Server (NTRS)

Rorie, Conrad; Fern, Lisa; Shively, Jay

2016-01-01

This presentation discusses the results of a recent UAS Integration into the NAS human-in-the-loop simulation. In the study, 16 active UAS pilots flew a UAS through civil airspace and were tasked with maintaining well clear from other aircraft in the area. Pilots performed the task with four different detect and avoid (DAA) traffic displays, each of which varied in the form of guidance it provided to pilots The present findings focus on how the different displays impacted pilots' measured response to scripted conflicts with their aircraft. Measured response is made up of several components, each of which help inform our understanding of the pilots' role in the overall detect and avoid task.

Functional neuroimaging of avoidance habits in OCD

PubMed Central

Gillan, Claire M; Apergis-Schoute, Annemieke M; Morein-Zamir, Sharon; Urcelay, Gonzalo P; Sule, Akeem; Fineberg, Naomi A; Sahakian, Barbara J; Robbins, Trevor W

2016-01-01

Objective The goal of this study was to determine the neural correlates of excessive habit formation in obsessive-compulsive disorder (OCD). We aimed to (i) test for neurobiological convergence with the known pathophysiology of OCD and (ii) infer, based on abnormalities in brain activation, whether these habits arise from dysfunction in the goal-directed or habit system. Method Thirty-seven OCD patients and 33 controls learned to avoid shocks while undergoing a functional Magnetic Resonance Imaging (fMRI) scan. Following 4 blocks of training, we tested if the avoidance response had become a habit by removing the threat of shock and measuring continued avoidance. We tested for task-related differences in brain activity in 3 ROIs, the caudate, putamen and medial orbitofrontal cortex at a statistical threshold of p<.05, family-wise error (FWE) corrected. Results We observed excessive habit formation in OCD patients, which was associated with hyper-activation in the caudate. Activation in this region was also associated with subjective ratings of increased urge to perform habits. The OCD group, as a whole, showed hyper-activation in the medial orbitofrontal cortex (mOFC) during the acquisition of avoidance, however this did not relate directly to habit formation. Conclusions OCD patients exhibited excessive habits that were associated with hyper-activation in a key region implicated in the pathophysiology of OCD, the caudate nucleus. Prior studies suggest that this region is important for goal-directed behavior, suggesting that habit-forming biases in OCD may be a result of impairments in this system, rather than differences in the build up of stimulus-response habits themselves. PMID:25526600

The neural implementation of task rule activation in the task-cuing paradigm: an event-related fMRI study.

PubMed

Shi, Yiquan; Zhou, Xiaolin; Müller, Hermann J; Schubert, Torsten

2010-07-01

To isolate the neural correlates for task rule activation from those related to general task preparation, the effect of a cue explicitly specifying the S-R correspondences (rule-cue) was contrasted with the effects of a cue specifying only the task to performed (task-cue). While the task-cue provides merely information about the type of task, the rule-cue is explicit about both the task type and the task rule (i.e., the set of S-R correspondences). The rule-cue was expected to activate the task rule more efficiently in the preparation period (prior to target presentation); by contrast, in the task-cue condition, part of the task rule activation was expected to be postponed into the task execution period (following the presentation of the target). In an event-related fMRI experiment, we found the right anterior and middle parts of the middle frontal and superior frontal gyri, the right inferior frontal junction, the pre-SMA, as well as the right superior and inferior parietal lobes to show larger activation elicited by the rule-cue than by the task-cue prior to target presentation. Conversely, the results revealed larger activations in these regions in the task-cue than in the rule-cue condition during the task execution period. In summary, this study identified some of the neural correlates of task rule activation and showed that these are a subset of the general task preparation network. Copyright (c) 2010 Elsevier Inc. All rights reserved.

For Which Side the Bell Tolls: The Laterality of Approach-Avoidance Associative Networks.

PubMed

Fetterman, Adam K; Ode, Scott; Robinson, Michael D

2013-03-01

The two hemispheres of the brain appear to play different roles in emotion and/or motivation. A great deal of previous research has examined the valence hypothesis (left hemisphere = positive; right = negative), but an increasing body of work has supported the motivational hypothesis (left hemisphere = approach; right = avoidance) as an alternative. The present investigation ( N = 117) sought to provide novel support for the latter perspective. Left versus right hemispheres were briefly activated by neutral lateralized auditory primes. Subsequently, participants categorized approach versus avoidance words as quickly and accurately as possible. Performance in the task revealed that approach-related thoughts were more accessible following left-hemispheric activation, whereas avoidance-related thoughts were more accessible following right-hemispheric activation. The present results are the first to examine such lateralized differences in accessible motivational thoughts, which may underlie more "downstream" manifestations of approach and avoidance motivation such as judgments, decision making, and behavior.

Activation of β-adrenoceptor facilitates active avoidance learning through enhancement of glutamate levels in the hippocampal dentate gyrus.

PubMed

Lv, Jing; Feng, Hao; Chen, Ling; Wang, Wei-Yao; Yue, Xue-Ling; Jin, Qing-Hua

2017-10-18

Long-term potentiation (LTP) is widely accepted as the best studied model for neurophysiological mechanisms that could underlie learning and memory formation. Despite a number of studies indicating that β-adrenoceptors in the hippocampal dentate gyrus (DG) is involved in the modulation of learning and memory as well as LTP, few studies have used glutamate release as a visual indicator in awake animals to explore the role of β-adrenoceptors in learning-dependent LTP. Therefore, in the present study, the effects of propranolol (an antagonist of β-adrenoceptor) and isoproterenol (an agonist of β-adrenoceptor) on extracellular concentrations of glutamate and amplitudes of field excitatory postsynaptic potential were measured in the DG region during active avoidance learning in freely moving conscious rats. In the control group, the glutamate level in the DG was significantly increased during the acquisition of active avoidance behavior and returned to basal level following extinction training. In propranolol group, antagonism of β-adrenoceptors in the DG significantly reduced the change in glutamate level, and the acquisition of the active avoidance behavior was significantly inhibited. In contrast, the change in glutamate level was significantly enhanced by isoproterenol, and the acquisition of the active avoidance behavior was significantly accelerated. Furthermore, in all groups, the changes in glutamate level were accompanied by corresponding changes in field excitatory postsynaptic potential amplitude and active avoidance behavior. Our results suggest that activation of β-adrenoceptors in the hippocampal DG facilitates active avoidance learning by modulations of glutamate level and synaptic efficiency in rats.

Task-discriminative space-by-time factorization of muscle activity

PubMed Central

Delis, Ioannis; Panzeri, Stefano; Pozzo, Thierry; Berret, Bastien

2015-01-01

Movement generation has been hypothesized to rely on a modular organization of muscle activity. Crucial to this hypothesis is the ability to perform reliably a variety of motor tasks by recruiting a limited set of modules and combining them in a task-dependent manner. Thus far, existing algorithms that extract putative modules of muscle activations, such as Non-negative Matrix Factorization (NMF), identify modular decompositions that maximize the reconstruction of the recorded EMG data. Typically, the functional role of the decompositions, i.e., task accomplishment, is only assessed a posteriori. However, as motor actions are defined in task space, we suggest that motor modules should be computed in task space too. In this study, we propose a new module extraction algorithm, named DsNM3F, that uses task information during the module identification process. DsNM3F extends our previous space-by-time decomposition method (the so-called sNM3F algorithm, which could assess task performance only after having computed modules) to identify modules gauging between two complementary objectives: reconstruction of the original data and reliable discrimination of the performed tasks. We show that DsNM3F recovers the task dependence of module activations more accurately than sNM3F. We also apply it to electromyographic signals recorded during performance of a variety of arm pointing tasks and identify spatial and temporal modules of muscle activity that are highly consistent with previous studies. DsNM3F achieves perfect task categorization without significant loss in data approximation when task information is available and generalizes as well as sNM3F when applied to new data. These findings suggest that the space-by-time decomposition of muscle activity finds robust task-discriminating modular representations of muscle activity and that the insertion of task discrimination objectives is useful for describing the task modulation of module recruitment. PMID:26217213

Change in hippocampal theta activity with transfer from simple discrimination tasks to a simultaneous feature-negative task

PubMed Central

Sakimoto, Yuya; Sakata, Shogo

2014-01-01

It was showed that solving a simple discrimination task (A+, B−) and a simultaneous feature-negative (FN) task (A+, AB−) used the hippocampal-independent strategy. Recently, we showed that the number of sessions required for a rat to completely learn a task differed between the FN and simple discrimination tasks, and there was a difference in hippocampal theta activity between these tasks. These results suggested that solving the FN task relied on a different strategy than the simple discrimination task. In this study, we provided supportive evidence that solving the FN and simple discrimination tasks involved different strategies by examining changes in performance and hippocampal theta activity in the FN task after transfer from the simple discrimination task (A+, B− → A+, AB−). The results of this study showed that performance on the FN task was impaired and there was a difference in hippocampal theta activity between the simple discrimination task and FN task. Thus, we concluded that solving the FN task uses a different strategy than the simple discrimination task. PMID:24917797

Intersection collision avoidance using ITS countermeasures. Task 9, Intersection collision avoidance system performance guidelines

DOT National Transportation Integrated Search

2000-09-01

Phase III of the Intersection Collision Avoidance Using ITS Countermeasures program developed testbed systems, implemented the systems on a vehicle, and performed testing to determine the potential effectiveness of this system in preventing intersect...

Behavioral and neural correlates of loss aversion and risk avoidance in adolescents and adults.

PubMed

Barkley-Levenson, Emily E; Van Leijenhorst, Linda; Galván, Adriana

2013-01-01

Individuals are frequently faced with risky decisions involving the potential for both gain and loss. Exploring the role of both potential gains and potential losses in predicting risk taking is critical to understanding how adolescents and adults make the choice to engage in or avoid a real-life risk. This study aimed to examine the impact of potential losses as well as gains on adolescent decisions during risky choice in a laboratory task. Adolescent (n=18) and adult (n=16) participants underwent functional magnetic resonance imaging (fMRI) during a mixed gambles task, and completed questionnaires measuring real-world risk-taking behaviors. While potential loss had a significantly greater effect on choice than potential gain in both adolescents and adults and there were no behavioral group differences on the task, adolescents recruited significantly more frontostriatal circuitry than adults when choosing to reject a gamble. During risk-seeking behavior, adolescent activation in medial prefrontal cortex (mPFC) was negatively correlated with self-reported likelihood of risk taking. During risk-avoidant behavior, mPFC activation of in adults was negatively correlated with self-reported benefits of risk-taking. Taken together, these findings reflect different neural patterns during risk-taking and risk-avoidant behaviors in adolescents and adults. Copyright © 2012 Elsevier Ltd. All rights reserved.

TRIMETHYLTIN IMPAIRS RETENTION OF A PASSIVE AVOIDANCE TASK

EPA Science Inventory

Trimethyltin is a neurotoxic organometal which produces neuronal damage in several limbic regions including the hippocampus, amygdala and the pyriform cortex. One administration of trimethyltin (5,6 or 7 mg/kg) twenty one days prior to passive avoidance conditioning produced an i...

Meditation leads to reduced default mode network activity beyond an active task

PubMed Central

Garrison, Kathleen A.; Zeffiro, Thomas A.; Scheinost, Dustin; Constable, R. Todd; Brewer, Judson A.

2015-01-01

Meditation has been associated with relatively reduced activity in the default mode network, a brain network implicated in self-related thinking and mind wandering. However, previous imaging studies have typically compared meditation to rest despite other studies reporting differences in brain activation patterns between meditators and controls at rest. Moreover, rest is associated with a range of brain activation patterns across individuals that has only recently begun to be better characterized. Therefore, this study compared meditation to another active cognitive task, both to replicate findings that meditation is associated with relatively reduced default mode network activity, and to extend these findings by testing whether default mode activity was reduced during meditation beyond the typical reductions observed during effortful tasks. In addition, prior studies have used small groups, whereas the current study tested these hypotheses in a larger group. Results indicate that meditation is associated with reduced activations in the default mode network relative to an active task in meditators compared to controls. Regions of the default mode showing a group by task interaction include the posterior cingulate/precuneus and anterior cingulate cortex. These findings replicate and extend prior work indicating that suppression of default mode processing may represent a central neural process in long-term meditation, and suggest that meditation leads to relatively reduced default mode processing beyond that observed during another active cognitive task. PMID:25904238

For Which Side the Bell Tolls: The Laterality of Approach-Avoidance Associative Networks

PubMed Central

Fetterman, Adam K.; Ode, Scott; Robinson, Michael D.

2012-01-01

The two hemispheres of the brain appear to play different roles in emotion and/or motivation. A great deal of previous research has examined the valence hypothesis (left hemisphere = positive; right = negative), but an increasing body of work has supported the motivational hypothesis (left hemisphere = approach; right = avoidance) as an alternative. The present investigation (N = 117) sought to provide novel support for the latter perspective. Left versus right hemispheres were briefly activated by neutral lateralized auditory primes. Subsequently, participants categorized approach versus avoidance words as quickly and accurately as possible. Performance in the task revealed that approach-related thoughts were more accessible following left-hemispheric activation, whereas avoidance-related thoughts were more accessible following right-hemispheric activation. The present results are the first to examine such lateralized differences in accessible motivational thoughts, which may underlie more “downstream” manifestations of approach and avoidance motivation such as judgments, decision making, and behavior. PMID:23869114

Meditation leads to reduced default mode network activity beyond an active task.

PubMed

Garrison, Kathleen A; Zeffiro, Thomas A; Scheinost, Dustin; Constable, R Todd; Brewer, Judson A

2015-09-01

Meditation has been associated with relatively reduced activity in the default mode network, a brain network implicated in self-related thinking and mind wandering. However, previous imaging studies have typically compared meditation to rest, despite other studies having reported differences in brain activation patterns between meditators and controls at rest. Moreover, rest is associated with a range of brain activation patterns across individuals that has only recently begun to be better characterized. Therefore, in this study we compared meditation to another active cognitive task, both to replicate the findings that meditation is associated with relatively reduced default mode network activity and to extend these findings by testing whether default mode activity was reduced during meditation, beyond the typical reductions observed during effortful tasks. In addition, prior studies had used small groups, whereas in the present study we tested these hypotheses in a larger group. The results indicated that meditation is associated with reduced activations in the default mode network, relative to an active task, for meditators as compared to controls. Regions of the default mode network showing a Group × Task interaction included the posterior cingulate/precuneus and anterior cingulate cortex. These findings replicate and extend prior work indicating that the suppression of default mode processing may represent a central neural process in long-term meditation, and they suggest that meditation leads to relatively reduced default mode processing beyond that observed during another active cognitive task.

Successive and discrete spaced conditioning in active avoidance learning in young and aged zebrafish.

PubMed

Yang, Peng; Kajiwara, Riki; Tonoki, Ayako; Itoh, Motoyuki

2018-05-01

We designed an automated device to study active avoidance learning abilities of zebrafish. Open source tools were used for the device control, statistical computing, and graphic outputs of data. Using the system, we developed active avoidance tests to examine the effects of trial spacing and aging on learning. Seven-month-old fish showed stronger avoidance behavior as measured by color preference index with discrete spaced training as compared to successive spaced training. Fifteen-month-old fish showed a similar trend, but with reduced cognitive abilities compared with 7-month-old fish. Further, in 7-month-old fish, an increase in learning ability during trials was observed with discrete, but not successive, spaced training. In contrast, 15-month-old fish did not show increase in learning ability during trials. Therefore, these data suggest that discrete spacing is more effective for learning than successive spacing, with the zebrafish active avoidance paradigm, and that the time course analysis of active avoidance using discrete spaced training is useful to detect age-related learning impairment. Copyright © 2017 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved.

Thinking About a Task Is Associated with Increased Connectivity in Regions Activated by Task Performance

PubMed Central

Robertson, Edwin M.; Manoach, Dara S.; Stickgold, Robert

2016-01-01

Abstract We investigated whether functional neuroimaging of quiet “rest” can reveal the neural correlates of conscious thought. Using resting-state functional MRI, we measured functional connectivity during a resting scan that immediately followed performance of a finger tapping motor sequence task. Self-reports of the amount of time spent thinking about the task during the resting scan correlated with connectivity between regions of the motor network activated during task performance. Thus, thinking about a task is associated with coordinated activity in brain regions responsible for that task's performance. More generally, this study demonstrates the feasibility of using the combination of functional connectivity MRI and self-reports to examine the neural correlates of thought. PMID:26650337

Gastrodia elata Bl. Attenuated learning deficits induced by forced-swimming stress in the inhibitory avoidance task and Morris water maze.

PubMed

Chen, Pei-Ju; Liang, Keng-Chen; Lin, Hui-Chen; Hsieh, Ching-Liang; Su, Kuan-Pin; Hung, Mei-Chu; Sheen, Lee-Yan

2011-06-01

This study adopted the forced-swimming paradigm to induce depressive symptoms in rats and evaluated the effects on learning and memory processing. Furthermore, the effects of the water extract of Gastrodia elata Bl., a well-known Chinese traditional medicine, on amnesia in rats subjected to the forced-swimming procedure were studied. Rats were subjected to the forced-swimming procedure, and the inhibitory avoidance task and Morris water maze were used to assess learning and memory performance. The acquisition of the two tasks was mostly impaired after the 15-minute forced-swimming procedure. Administration of the water extract of G. elata Bl. for 21 consecutive days at a dosage of 0.5 or 1.0 g/kg of body weight significantly improved retention in the inhibitory avoidance test, and the lower dose showed a better effect than the higher one and the antidepressant fluoxetine (18 mg/kg of body weight). In the Morris water maze, the lower dose of the water extract of G. elata Bl. significantly improved retention by shortening escape latency in the first test session and increasing the time in searching the target zone during the probe test. These findings suggest that water extracts of G. elata Bl. ameliorate the learning and memory deficits induced by forced swimming.

Males and females differ in brain activation during cognitive tasks.

PubMed

Bell, Emily C; Willson, Morgan C; Wilman, Alan H; Dave, Sanjay; Silverstone, Peter H

2006-04-01

To examine the effect of gender on regional brain activity, we utilized functional magnetic resonance imaging (fMRI) during a motor task and three cognitive tasks; a word generation task, a spatial attention task, and a working memory task in healthy male (n = 23) and female (n = 10) volunteers. Functional data were examined for group differences both in the number of pixels activated, and the blood-oxygen-level-dependent (BOLD) magnitude during each task. Males had a significantly greater mean activation than females in the working memory task with a greater number of pixels being activated in the right superior parietal gyrus and right inferior occipital gyrus, and a greater BOLD magnitude occurring in the left inferior parietal lobe. However, despite these fMRI changes, there were no significant differences between males and females on cognitive performance of the task. In contrast, in the spatial attention task, men performed better at this task than women, but there were no significant functional differences between the two groups. In the word generation task, there were no external measures of performance, but in the functional measurements, males had a significantly greater mean activation than females, where males had a significantly greater BOLD signal magnitude in the left and right dorsolateral prefrontal cortex, the right inferior parietal lobe, and the cingulate. In neither of the motor tasks (right or left hand) did males and females perform differently. Our fMRI findings during the motor tasks were a greater mean BOLD signal magnitude in males in the right hand motor task, compared to females where males had an increased BOLD signal magnitude in the right inferior parietal gyrus and in the left inferior frontal gyrus. In conclusion, these results demonstrate differential patterns of activation in males and females during a variety of cognitive tasks, even though performance in these tasks may not vary, and also that variability in performance may not

Automatic honesty forgoing reward acquisition and punishment avoidance: a functional MRI investigation

PubMed Central

Yoneda, Mei; Ueda, Ryuhei; Ashida, Hiroshi

2017-01-01

Recent neuroimaging investigations into human honesty suggest that honest moral decisions in individuals who consistently behave honestly occur automatically, without the need for active self-control. However, it remains unclear whether this observation can be applied to two different types of honesty: honesty forgoing dishonest reward acquisition and honesty forgoing dishonest punishment avoidance. To address this issue, a functional MRI study, using an incentivized prediction task in which participants were confronted with real and repeated opportunities for dishonest gain leading to reward acquisition and punishment avoidance, was conducted. Behavioral data revealed that the frequency of dishonesty was equivalent between the opportunities for dishonest reward acquisition and for punishment avoidance. Reaction time data demonstrated that two types of honest decisions in the opportunity for dishonest reward acquisition and punishment avoidance required no additional cognitive control. Neuroimaging data revealed that honest decisions in the opportunity for dishonest reward acquisition and those for punishment avoidance required no additional control-related activity compared with a control condition in which no opportunity for dishonest behavior was given. These results suggest that honesty flows automatically, irrespective of the concomitant motivation for dishonesty leading to reward acquisition and punishment avoidance. PMID:28746066

Automatic honesty forgoing reward acquisition and punishment avoidance: a functional MRI investigation.

PubMed

Yoneda, Mei; Ueda, Ryuhei; Ashida, Hiroshi; Abe, Nobuhito

2017-09-27

Recent neuroimaging investigations into human honesty suggest that honest moral decisions in individuals who consistently behave honestly occur automatically, without the need for active self-control. However, it remains unclear whether this observation can be applied to two different types of honesty: honesty forgoing dishonest reward acquisition and honesty forgoing dishonest punishment avoidance. To address this issue, a functional MRI study, using an incentivized prediction task in which participants were confronted with real and repeated opportunities for dishonest gain leading to reward acquisition and punishment avoidance, was conducted. Behavioral data revealed that the frequency of dishonesty was equivalent between the opportunities for dishonest reward acquisition and for punishment avoidance. Reaction time data demonstrated that two types of honest decisions in the opportunity for dishonest reward acquisition and punishment avoidance required no additional cognitive control. Neuroimaging data revealed that honest decisions in the opportunity for dishonest reward acquisition and those for punishment avoidance required no additional control-related activity compared with a control condition in which no opportunity for dishonest behavior was given. These results suggest that honesty flows automatically, irrespective of the concomitant motivation for dishonesty leading to reward acquisition and punishment avoidance.

Seeing direct and averted gaze activates the approach-avoidance motivational brain systems.

PubMed

Hietanen, Jari K; Leppänen, Jukka M; Peltola, Mikko J; Linna-Aho, Kati; Ruuhiala, Heidi J

2008-01-01

Gaze direction is known to be an important factor in regulating social interaction. Recent evidence suggests that direct and averted gaze can signal the sender's motivational tendencies of approach and avoidance, respectively. We aimed at determining whether seeing another person's direct vs. averted gaze has an influence on the observer's neural approach-avoidance responses. We also examined whether it would make a difference if the participants were looking at the face of a real person or a picture. Measurements of hemispheric asymmetry in the frontal electroencephalographic activity indicated that another person's direct gaze elicited a relative left-sided frontal EEG activation (indicative of a tendency to approach), whereas averted gaze activated right-sided asymmetry (indicative of avoidance). Skin conductance responses were larger to faces than to control objects and to direct relative to averted gaze, indicating that faces, in general, and faces with direct gaze, in particular, elicited more intense autonomic activation and strength of the motivational tendencies than did control stimuli. Gaze direction also influenced subjective ratings of emotional arousal and valence. However, all these effects were observed only when participants were facing a real person, not when looking at a picture of a face. This finding was suggested to be due to the motivational responses to gaze direction being activated in the context of enhanced self-awareness by the presence of another person. The present results, thus, provide direct evidence that eye contact and gaze aversion between two persons influence the neural mechanisms regulating basic motivational-emotional responses and differentially activate the motivational approach-avoidance brain systems.

[Effect of 5-HT1A receptors in the hippocampal DG on active avoidance learning in rats].

PubMed

Jiang, Feng-ze; Lv, Jing; Wang, Dan; Jiang, Hai-ying; Li, Ying-shun; Jin, Qing-hua

2015-01-01

To investigate the effects of serotonin (5-HTIA) receptors in the hippocampal dentate gyrus (DG) on active avoidance learning in rats. Totally 36 SD rats were randomly divided into control group, antagonist group and agonist group(n = 12). Active avoidance learning ability of rats was assessed by the shuttle box. The extracellular concentrations of 5-HT in the DG during active avoidance conditioned reflex were measured by microdialysis and high performance liquid chromatography (HPLC) techniques. Then the antagonist (WAY-100635) or agonist (8-OH-DPAT) of the 5-HT1A receptors were microinjected into the DG region, and the active avoidance learning was measured. (1) During the active avoidance learning, the concentration of 5-HT in the hippocampal DG was significantly increased in the extinction but not establishment in the conditioned reflex, which reached 164.90% ± 26.07% (P <0.05) of basal level. (2) The microinjection of WAY-100635 (an antagonist of 5-HT1A receptor) into the DG did not significantly affect the active avoidance learning. (3) The microinjection of 8-OH-DPAT(an agonist of 5-HT1A receptor) into the DG significantly facilitated the establishment process and inhibited the extinction process during active avoidance conditioned reflex. The data suggest that activation of 5-HT1A receptors in hipocampal DG may facilitate active avoidance learning and memory in rats.

Prolongation of latencies for passive avoidance responses in rats treated with aniracetam or piracetam.

PubMed

Yamada, K; Inoue, T; Tanaka, M; Furukawa, T

1985-04-01

Effects of aniracetam (1-anysoyl-2-pyrrolodone) and piracetam (1-acetamido-2-pyrrolidone) on passive avoidance behavior were studied in 2 and 18 months old rats using a step-down passive avoidance task. Repeated administration of aniracetam (30 and 50 mg/kg, IP X 5 days) or piracetam (100 mg/kg, IP X 5 days) significantly prolonged step-down latencies for a passive avoidance task in 2 months old rats. Administration of aniracetam (50 mg/kg, IP) or piracetam (100 mg/kg, IP), however, did not affect locomotor activity. This prolongation of latencies was also seen with oral administration of aniracetam (50 mg/kg X 5 days). Similar prolongation of latencies also occurred in 18 months old rat treated with aniracetam (50 mg/kg, IP X 5 days). The results imply that aniracetam may improve learning and/or memory in 2 and 18 months old rats.

Not so bad: avoidance and aversive discounting modulate threat appraisal in anterior cingulate and medial prefrontal cortex

PubMed Central

Schlund, Michael W.; Brewer, Adam T.; Richman, David M.; Magee, Sandy K.; Dymond, Simon

2015-01-01

The dorsal anterior cingulate (adACC) and dorsal medial prefrontal cortex (dmPFC) play a central role in the discrimination and appraisal of threatening stimuli. Yet, little is known about what specific features of threatening situations recruit these regions and how avoidance may modulate appraisal and activation through prevention of aversive events. In this investigation, 30 healthy adults underwent functional neuroimaging while completing an avoidance task in which responses to an Avoidable CS+ threat prevented delivery of an aversive stimulus, but not to an Unavoidable CS+ threat. Extinction testing was also completed where CSs were presented without aversive stimulus delivery and an opportunity to avoid. The Avoidable CS+ relative to the Unavoidable CS+ was associated with reductions in ratings of negative valence, fear, and US expectancy and activation. Greater regional activation was consistently observed to the Unavoidable CS+ during avoidance, which declined during extinction. Individuals exhibiting greater aversive discounting—that is, those more avoidant of immediate monetary loss compared to a larger delayed loss—also displayed greater activation to the Unavoidable CS+, highlighting aversive discounting as a significant individual difference variable. These are the first results linking adACC/dmPFC reactivity to avoidance-based reductions of aversive events and modulation of activation by individual differences in aversive discounting. PMID:26113813

Higher threat avoidance costs reduce avoidance behaviour which in turn promotes fear extinction in humans.

PubMed

Rattel, Julina A; Miedl, Stephan F; Blechert, Jens; Wilhelm, Frank H

2017-09-01

Theoretical models specifying the underlying mechanisms of the development and maintenance of anxiety and related disorders state that fear responses acquired through classical Pavlovian conditioning are maintained by repeated avoidance behaviour; thus, it is assumed that avoidance prevents fear extinction. The present study investigated behavioural avoidance decisions as a function of avoidance costs in a naturalistic fear conditioning paradigm. Ecologically valid avoidance costs - manipulated between participant groups - were represented via time-delays during a detour in a gamified computer task. After differential acquisitions of shock-expectancy to a predictive conditioned stimulus (CS+), participants underwent extinction where they could either take a risky shortcut, while anticipating shock signaled by the CS+, or choose a costly avoidance option (lengthy detour); thus, they were faced with an approach-avoidance conflict. Groups with higher avoidance costs (longer detours) showed lower proportions of avoiders. Avoiders gave heightened shock-expectancy ratings post-extinction, demonstrating 'protecting from extinction', i.e. failure to extinguish. Moreover, there was an indirect effect of avoidance costs on protection from extinction through avoidance behaviour. No moderating role of trait-anxiety was found. Theoretical implications of avoidance behaviour are discussed, considering the involvement of instrumental learning in the maintenance of fear responses. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preparatory neural activity predicts performance on a conflict task.

PubMed

Stern, Emily R; Wager, Tor D; Egner, Tobias; Hirsch, Joy; Mangels, Jennifer A

2007-10-24

Advance preparation has been shown to improve the efficiency of conflict resolution. Yet, with little empirical work directly linking preparatory neural activity to the performance benefits of advance cueing, it is not clear whether this relationship results from preparatory activation of task-specific networks, or from activity associated with general alerting processes. Here, fMRI data were acquired during a spatial Stroop task in which advance cues either informed subjects of the upcoming relevant feature of conflict stimuli (spatial or semantic) or were neutral. Informative cues decreased reaction time (RT) relative to neutral cues, and cues indicating that spatial information would be task-relevant elicited greater activity than neutral cues in multiple areas, including right anterior prefrontal and bilateral parietal cortex. Additionally, preparatory activation in bilateral parietal cortex and right dorsolateral prefrontal cortex predicted faster RT when subjects responded to spatial location. No regions were found to be specific to semantic cues at conventional thresholds, and lowering the threshold further revealed little overlap between activity associated with spatial and semantic cueing effects, thereby demonstrating a single dissociation between activations related to preparing a spatial versus semantic task-set. This relationship between preparatory activation of spatial processing networks and efficient conflict resolution suggests that advance information can benefit performance by leading to domain-specific biasing of task-relevant information.

Greater avoidance behavior in individuals with posttraumatic stress disorder symptoms

PubMed Central

Sheynin, Jony; Shind, Christine; Radell, Milen; Ebanks-Williams, Yasheca; Gilbertson, Mark W.; Beck, Kevin D.; Myers, Catherine E.

2017-01-01

While avoidance is a core symptom of PTSD, little is known about whether individuals with PTSD show a general cognitive bias to acquire and express avoidance, in situations not related to trauma or fear. Here, we used a computer-based task to examine operant acquisition and extinction of avoidance in participants with and without severe self -reported PTSD symptoms. A total of 119 participants (77 male, 42 female; 74 veteran, 45 civilian) with symptoms (PTSS; n=63) or with few/no symptoms (noPTSS; n=56) performed a task, in which they controlled a spaceship and could shoot a target to gain points or hide in “safe areas” to escape or avoid on-screen aversive events. Results show that participants with PTSS exhibited more avoidance across trials than no PTSS participants, particularly due to more avoidance behavior in PTSS females compared to noPTSS females. Avoidance behavior decreased across extinction trials but interactions with PTSS and gender fell short of significance. Overall, PTSD symptoms were associated with propensity to acquire and express avoidance behavior, in both civilians and veterans, and even in a cognitive task that does not explicitly involve trauma or fear. This effect was more pronounced in females, highlighting the role of gender differences in PTSD symptomatology. Importantly, this study also demonstrates the potential of an objective assessment of avoidance behavior, which could be used to supplement the common but limited self-report tools. PMID:28322068

Greater avoidance behavior in individuals with posttraumatic stress disorder symptoms.

PubMed

Sheynin, Jony; Shind, Christine; Radell, Milen; Ebanks-Williams, Yasheca; Gilbertson, Mark W; Beck, Kevin D; Myers, Catherine E

2017-05-01

While avoidance is a core symptom of PTSD, little is known about whether individuals with PTSD show a general cognitive bias to acquire and express avoidance, in situations not related to trauma or fear. Here, we used a computer-based task to examine operant acquisition and extinction of avoidance in participants with and without severe self-reported PTSD symptoms. A total of 119 participants (77 male, 42 female; 74 veteran, 45 civilian) with symptoms (PTSS; n = 63) or with few/no symptoms (noPTSS; n = 56) performed a task, in which they controlled a spaceship and could shoot a target to gain points or hide in "safe areas" to escape or avoid on-screen aversive events. Results show that participants with PTSS exhibited more avoidance across trials than noPTSS participants, particularly due to more avoidance behavior in PTSS females compared to noPTSS females. Avoidance behavior decreased across extinction trials but interactions with PTSS and gender fell short of significance. Overall, PTSD symptoms were associated with propensity to acquire and express avoidance behavior, in both civilians and veterans, and even in a cognitive task that does not explicitly involve trauma or fear. This effect was more pronounced in females, highlighting the role of gender differences in PTSD symptomatology. Importantly, this study also demonstrates the potential of an objective assessment of avoidance behavior, which could be used to supplement the common but limited self-report tools.

Physical Activity Predicts Performance in an Unpracticed Bimanual Coordination Task.

PubMed

Boisgontier, Matthieu P; Serbruyns, Leen; Swinnen, Stephan P

2017-01-01

Practice of a given physical activity is known to improve the motor skills related to this activity. However, whether unrelated skills are also improved is still unclear. To test the impact of physical activity on an unpracticed motor task, 26 young adults completed the international physical activity questionnaire and performed a bimanual coordination task they had never practiced before. Results showed that higher total physical activity predicted higher performance in the bimanual task, controlling for multiple factors such as age, physical inactivity, music practice, and computer games practice. Linear mixed models allowed this effect of physical activity to be generalized to a large population of bimanual coordination conditions. This finding runs counter to the notion that generalized motor abilities do not exist and supports the existence of a "learning to learn" skill that could be improved through physical activity and that impacts performance in tasks that are not necessarily related to the practiced activity.

Metacognitive evaluation in the avoidance of demand.

PubMed

Dunn, Timothy L; Lutes, David J C; Risko, Evan F

2016-09-01

In the current set of experiments our goal was to test the hypothesis that individuals avoid courses of action based on a kind of metacognitive evaluation of demand in a Demand Selection Task (DST). Individuals in Experiment 1 completed a DST utilizing visual stimuli known to yield a dissociation between performance and perceived demand. Patterns of demand avoidance followed that of perceived demand. Experiment 2 provided a replication of the aforementioned results, in addition to demonstrating a second dissociation between a peripheral physiological measure of demand (i.e., blink rates) and demand avoidance. Experiment 3 directly tested the assumption that individuals make use of a general metacognitive evaluation of task demand during selections. A DST was utilized in a forced-choice paradigm that required individuals to either select the most effortful, time demanding, or least accurate of 2 choices. Patterns of selections were similar across all rating dimensions, lending credit to this notion. Findings are discussed within a metacognitive framework of demand avoidance and contrasted to current theories. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Flexible conflict management: conflict avoidance and conflict adjustment in reactive cognitive control.

PubMed

Dignath, David; Kiesel, Andrea; Eder, Andreas B

2015-07-01

Conflict processing is assumed to serve two crucial, yet distinct functions: Regarding task performance, control is adjusted to overcome the conflict. Regarding task choice, control is harnessed to bias decision making away from the source of conflict. Despite recent theoretical progress, until now two lines of research addressed these conflict-management strategies independently of each other. In this research, we used a voluntary task-switching paradigm in combination with response interference tasks to study both strategies in concert. In Experiment 1, participants chose between two univalent tasks on each trial. Switch rates increased following conflict trials, indicating avoidance of conflict. Furthermore, congruency effects in reaction times and error rates were reduced following conflict trials, demonstrating conflict adjustment. In Experiment 2, we used bivalent instead of univalent stimuli. Conflict adjustment in task performance was unaffected by this manipulation, but conflict avoidance was not observed. Instead, task switches were reduced after conflict trials. In Experiment 3, we used tasks comprising univalent or bivalent stimuli. Only tasks with univalent revealed conflict avoidance, whereas conflict adjustment was found for all tasks. On the basis of established theories of cognitive control, an integrative process model is described that can account for flexible conflict management. (c) 2015 APA, all rights reserved.

Scapular kinematics and muscle activities during pushing tasks.

PubMed

Huang, Chun-Kai; Siu, Ka-Chun; Lien, Hen-Yu; Lee, Yun-Ju; Lin, Yang-Hua

2013-01-01

Pushing tasks are functional activities of daily living. However, shoulder complaints exist among workers exposed to regular pushing conditions. It is crucial to investigate the control of shoulder girdles during pushing tasks. The objective of the study was to demonstrate scapular muscle activities and motions on the dominant side during pushing tasks and the relationship between scapular kinematics and muscle activities in different pushing conditions. Thirty healthy adults were recruited to push a four-wheel cart in six pushing conditions. The electromyographic signals of the upper trapezius (UT) and serratus anterior (SA) muscles were recorded. A video-based system was used for measuring the movement of the shoulder girdle and scapular kinematics. Differences in scapular kinematics and muscle activities due to the effects of handle heights and weights of the cart were analyzed using two-way ANOVA with repeated measures. The relationships between scapular kinematics and muscle activities were examined by Pearson's correlation coefficients. The changes in upper trapezius and serratus anterior muscle activities increased significantly with increased pushing weights in the one-step pushing phase. The UT/SA ratio on the dominant side decreases significantly with increased handle heights in the one-step pushing phase. The changes in upward rotation, lateral slide and elevation of the scapula decreased with increased pushing loads in the trunk-forward pushing phase. This study indicated that increased pushing loads result in decreased motions of upward rotation, lateral slide and elevation of the scapula; decreased handle heights result in relatively increased activities of the serratus anterior muscles during pushing tasks.

Prior fear conditioning does not impede enhanced active avoidance in serotonin transporter knockout rats.

PubMed

Schipper, Pieter; Henckens, Marloes J A G; Borghans, Bart; Hiemstra, Marlies; Kozicz, Tamas; Homberg, Judith R

2017-05-30

Stressors can be actively or passively coped with, and adequate adaption of the coping response to environmental conditions can reduce their potential deleterious effects. One major factor influencing stress coping behaviour is serotonin transporter (5-HTT) availability. Abolishment of 5-HTT is known to impair fear extinction but facilitates acquisition of signalled active avoidance (AA), a behavioural task in which an animal learns to avoid an aversive stimulus that is predicted by a cue. Flexibility in adapting coping behaviour to the nature of the stressor shapes resilience to stress-related disorders. Therefore, we investigated the relation between 5-HTT expression and ability to adapt a learned coping response to changing environmental conditions. To this end, we first established and consolidated a cue-conditioned passive fear response in 5-HTT -/- and wildtype rats. Next, we used the conditioned stimulus (CS) to signal oncoming shocks during signalled AA training in 5-HTT -/- and wildtype rats to study their capability to acquire an active coping response to the CS following fear conditioning. Finally, we investigated the behavioural response to the CS in a novel environment and measured freezing, exploration and self-grooming, behaviours reflective of stress coping strategy. We found that fear conditioned and sham conditioned 5-HTT -/- animals acquired the signalled AA response faster than wildtypes, while prior conditioning briefly delayed AA learning similarly in both genotypes. Subsequent exposure to the CS in the novel context reduced freezing and increased locomotion in 5-HTT -/- compared to wildtype rats. This indicates that improved AA performance in 5-HTT -/- rats resulted in a weaker residual passive fear response to the CS in a novel context. Fear conditioning prior to AA training did not affect freezing upon re-encountering the CS, although it did reduce locomotion in 5-HTT -/- rats. We conclude that independent of 5-HTT signalling, prior fear

Increased task-uncorrelated muscle activity in childhood dystonia.

PubMed

Lunardini, Francesca; Maggioni, Serena; Casellato, Claudia; Bertucco, Matteo; Pedrocchi, Alessandra L G; Sanger, Terence D

2015-06-12

Even if movement abnormalities in dystonia are obvious on observation-based examinations, objective measures to characterize dystonia and to gain insights into its pathophysiology are still strongly needed. We hypothesize that motor abnormalities in childhood dystonia are partially due to the inability to suppress involuntary variable muscle activity irrelevant to the achievement of the desired motor task, resulting in the superposition of unwanted motion components on the desired movement. However, it is difficult to separate and quantify appropriate and inappropriate motor signals combined in the same muscle, especially during movement. We devise an innovative and practical method to objectively measure movement abnormalities during the performance of a continuous figure-eight writing task in 7 children with dystonia and 9 age-matched healthy controls. During the execution of a continuous writing task, muscle contractions should occur at frequencies that match the frequencies of the writing outcome. We compare the power spectra of kinematic trajectories and electromyographic signals of 8 upper limb muscles to separate muscle activity with the same frequency content of the figure-eight movement (task-correlated) from activity occurring at frequencies extraneous to the task (task-uncorrelated). Children with dystonia present a greater magnitude of task-uncorrelated muscle components. The motor performance achieved by children with dystonia is characterized by an overall lower quality, with high spatial and temporal variability and an altered trade-off between speed and accuracy. Findings are consistent with the hypothesis that, in childhood dystonia, the ability to appropriately suppress variable and uncorrelated elements of movement is impaired. Here we present a proof-of-concept of a promising tool to characterize the phenomenology of movement disorders and to inform the design of neurorehabilitation therapies.

The n-butanolic extract of Opuntia ficus-indica var. saboten enhances long-term memory in the passive avoidance task in mice.

PubMed

Kim, Jong Min; Kim, Dong Hyun; Park, Se Jin; Park, Dong Hyun; Jung, Seo Yun; Kim, Hyoung Ja; Lee, Yong Sup; Jin, Changbae; Ryu, Jong Hoon

2010-08-16

Opuntia ficus-indica var. saboten Makino (Cactaceae) is used to treat burns, edema, dyspepsia, and asthma in traditional medicine. The present study investigated the beneficial effects of the n-butanolic extract of O. ficus-indica var. saboten (BOF) on memory performance in mice and attempts to uncover the mechanisms underlying its action. Memory performance was assessed with the passive avoidance task, and western blotting and immunohistochemistry were used to measure changes in protein expression and cell survival. After the oral administration of BOF for 7 days, the latency time in the passive avoidance task was significantly increased relative to vehicle-treated controls (P<0.05). Western blotting revealed that the expression levels of brain-derived neurotrophic factor (BDNF), phosphorylated cAMP response element binding-protein (pCREB), and phosphorylated extracellular signal-regulated kinase (pERK) 1/2 were significantly increased in hippocampal tissue after 7 days of BOF administration (P<0.05). Doublecortin and 5-bromo-2-deoxyuridine immunostaining also revealed that BOF significantly enhanced the survival of immature neurons, but did not affect neuronal cell proliferation in the subgranular zone of the hippocampal dentate gyrus. These results suggest that the subchronic administration of BOF enhances long-term memory, and that this effect is partially mediated by ERK-CREB-BDNF signaling and the survival of immature neurons. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Active Collision Avoidance for Planetary Landers

NASA Technical Reports Server (NTRS)

Rickman, Doug; Hannan, Mike; Srinivasan, Karthik

2015-01-01

The use of automotive radar systems are being evaluated for collision avoidance in planetary landers. Our focus is to develop a low-cost, light-weight collision avoidance system that overcomes the drawbacks identified with optical-based systems. We also seek to complement the Autonomous Landing and Hazard Avoidance Technology system by providing mission planners an alternative system that can be used on low-cost, small robotic missions and in close approach. Our approach takes advantage of how electromagnetic radiation interacts with solids. As the wavelength increases, the sensitivity of the radiation to isolated solids of a specific particle size decreases. Thus, rocket exhaust-blown dust particles, which have major significance in visible wavelengths, have much less significance at radar wavelengths.

Obstacle avoidance locomotor tasks: adaptation, memory and skill transfer.

PubMed

Kloter, Evelyne; Dietz, Volker

2012-05-01

The aim of this study was to explore the neural basis of adaptation, memory and skill transfer during human stepping over obstacles. Whilst walking on a treadmill, subjects had to perform uni- and bilateral obstacle steps. Acoustic feedback information about foot clearance was provided. Non-noxious electrical stimuli were applied to the right tibial nerve during the mid-stance phase of the right leg, i.e. 'prior' to the right or 'during' the left leg swing over the obstacle. The electromyogram (EMG) responses evoked by these stimuli in arm and leg muscles are known to reflect the neural coordination during normal and obstacle steps. The leading and trailing legs rapidly adapted foot clearance during obstacle steps with small further changes when the same obstacle condition was repeated. This adaptation was associated with a corresponding decrease in arm and leg muscle reflex EMG responses. Arm (but not leg) muscle EMG responses were greater when the stimulus was applied 'during' obstacle crossing by the left leg leading compared with stimulation 'prior' to right leg swing over the obstacle. A corresponding difference existed in arm muscle background EMG. The results indicate that, firstly, the somatosensory information gained by the performance and adaptation of uni- and bilateral obstacle stepping becomes transferred to the trailing leg in a context-specific manner. Secondly, EMG activity in arm and leg muscles parallels biomechanical adaptation of foot clearance. Thirdly, a consistently high EMG activity in the arm muscles during swing over the obstacle is required for equilibrium control. Thus, such a precision locomotor task is achieved by a context-specific, coordinated activation of arm and leg muscles for performance and equilibrium control that includes adaptation, memory and skill transfer. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

Time Out from Sex or Romance: Sexually Experienced Adolescents' Decisions to Purposefully Avoid Sexual Activity or Romantic Relationships.

PubMed

Byers, E Sandra; O'Sullivan, Lucia F; Brotto, Lori A

2016-05-01

Researchers have given significant attention to abstinence among adolescents, but far less is known about purposeful avoidance of sexual activity (and relationship involvement). Typically, it is assumed that, once adolescents have initiated sexual activity, they will thereafter engage in sexual activity if given the opportunity. However, it is unclear whether that is true as some research indicates that many adolescents engage in sexual activity intermittently. Sexually experienced adolescents may purposefully avoid engaging in sexual activity for a period of time and, if so, this has implications for understanding their sexual decision-making. We used a mixed methods approach to investigate sexually experienced adolescents' decisions to purposefully avoid further sexual activity and/or romantic relationships with a focus on how common these decisions are and factors influencing them. Participants were 411 (56 % female) adolescents (16-21 years old) who completed an on-line survey that assessed reasons for each type of avoidance, religiosity, sexual esteem, sexual distress, sexual coercion, and dysfunctional sexual beliefs. Overall, 27 % of participants had engaged in sexual avoidance and 47 % had engaged in romantic avoidance. Significantly more female than male adolescents reported sexual and romantic avoidance. Adolescents' reasons for sexual avoidance included: lack of sexual pleasure or enjoyment, relationship reasons, negative emotions, values, fear of negative outcomes, negative physical experience, and other priorities. Reasons for romantic avoidance included: effects of previous relationship, not interested in commitment, wrong time, other priorities, negative emotions, no one was good enough, and sexual concerns. Logistical regressions were used to assess associations between age, religiosity, sexual esteem, sexual distress, experience of sexual coercion, and dysfunctional sexual beliefs and having engaged in romantic and/or sexual avoidance. The

Functional neuroimaging of avoidance habits in obsessive-compulsive disorder.

PubMed

Gillan, Claire M; Apergis-Schoute, Annemieke M; Morein-Zamir, Sharon; Urcelay, Gonzalo P; Sule, Akeem; Fineberg, Naomi A; Sahakian, Barbara J; Robbins, Trevor W

2015-03-01

The purpose of this study was to determine the neural correlates of excessive habit formation in obsessive-compulsive disorder (OCD). The authors aimed to test for neurobiological convergence with the known pathophysiology of OCD and to infer, based on abnormalities in brain activation, whether these habits arise from dysfunction in the goal-directed or habit system. Thirty-seven OCD patients and 33 healthy comparison subjects learned to avoid shocks while undergoing a functional MRI scan. Following four blocks of training, the authors tested whether the avoidance response had become a habit by removing the threat of shock and measuring continued avoidance. Task-related differences in brain activity in three regions of interest (the caudate, the putamen, and the medial orbitofrontal cortex) were tested at a statistical threshold set at <0.05 (family-wise-error corrected). Excessive habit formation in OCD patients, which was associated with hyperactivation in the caudate, was observed. Activation in this region was also associated with subjective ratings of increased urge to perform habits. The OCD group, as a whole, showed hyperactivation in the medial orbitofrontal cortex during the acquisition of avoidance; however, this did not relate directly to habit formation. OCD patients exhibited excessive habits that were associated with hyperactivation in a key region implicated in the pathophysiology of OCD, the caudate nucleus. Previous studies indicate that this region is important for goal-directed behavior, suggesting that habit-forming biases in OCD may be a result of impairments in this system, rather than differences in the buildup of stimulus-response habits themselves.

"Watch out!": Effects of instructed threat and avoidance on human free-operant approach-avoidance behavior.

PubMed

Schlund, Michael W; Treacher, Kay; Preston, Oli; Magee, Sandy K; Richman, David M; Brewer, Adam T; Cameron, Gemma; Dymond, Simon

2017-01-01

Approach-avoidance paradigms create a competition between appetitive and aversive contingencies and are widely used in nonhuman research on anxiety. Here, we examined how instructions about threat and avoidance impact control by competing contingencies over human approach-avoidance behavior. Additionally, Experiment 1 examined the effects of threat magnitude (money loss amount) and avoidance cost (fixed ratio requirements), whereas Experiment 2 examined the effects of threat information (available, unavailable and inaccurate) on approach-avoidance. During the task, approach responding was modeled by reinforcing responding with money on a FR schedule. By performing an observing response, participants produced an escalating "threat meter". Instructions stated that the threat meter levels displayed the current probability of losing money, when in fact loss only occurred when the level reached the maximum. Instructions also stated pressing an avoidance button lowered the threat level. Overall, instructions produced cycles of approach and avoidance responding with transitions from approach to avoidance when threat was high and transitions back to approach after avoidance reduced threat. Experiment 1 revealed increasing avoidance cost, but not threat magnitude, shifted approach-avoidance transitions to higher threat levels and increased anxiety ratings, but did not influence the frequency of approach-avoidance cycles. Experiment 2 revealed when threat level information was available or absent earnings were high, but earnings decreased when inaccurate threat information was incompatible with contingencies. Our findings build on prior nonhuman and human approach-avoidance research by highlighting how instructed threat and avoidance can impact human AA behavior and self-reported anxiety. © 2017 Society for the Experimental Analysis of Behavior.

Response Activation in Overlapping Tasks and the Response-Selection Bottleneck

ERIC Educational Resources Information Center

Schubert, Torsten; Fischer, Rico; Stelzel, Christine

2008-01-01

The authors investigated the impact of response activation on dual-task performance by presenting a subliminal prime before the stimulus in Task 2 (S2) of a psychological refractory period (PRP) task. Congruence between prime and S2 modulated the reaction times in Task 2 at short stimulus onset asynchrony despite a PRP effect. This Task 2…

Telencephalic neural activation following passive avoidance learning in a terrestrial toad.

PubMed

Puddington, Martín M; Daneri, M Florencia; Papini, Mauricio R; Muzio, Rubén N

2016-12-15

The present study explores passive avoidance learning and its neural basis in toads (Rhinella arenarum). In Experiment 1, two groups of toads learned to move from a lighted compartment into a dark compartment. After responding, animals in the experimental condition were exposed to an 800-mM strongly hypertonic NaCl solution that leads to weight loss. Control animals received exposure to a 300-mM slightly hypertonic NaCl solution that leads to neither weight gain nor loss. After 10 daily acquisition trials, animals in the experimental group showed significantly longer latency to enter the dark compartment. Additionally, 10 daily trials in which both groups received the 300-mM NaCl solution after responding eliminated this group effect. Thus, experimental animals showed gradual acquisition and extinction of a passive avoidance respond. Experiment 2 replicated the gradual acquisition effect, but, after the last trial, animals were sacrificed and neural activation was assessed in five brain regions using AgNOR staining for nucleoli-an index of brain activity. Higher activation in the experimental animals, relative to controls, was observed in the amygdala and striatum. Group differences in two other regions, lateral pallium and septum, were borderline, but nonsignificant, whereas group differences in the medial pallium were nonsignificant. These preliminary results suggest that a striatal-amygdala activation could be a key component of the brain circuit controlling passive avoidance learning in amphibians. The results are discussed in relation to the results of analogous experiments with other vertebrates. Copyright © 2016 Elsevier B.V. All rights reserved.

Alterations in Resting-State Activity Relate to Performance in a Verbal Recognition Task

PubMed Central

López Zunini, Rocío A.; Thivierge, Jean-Philippe; Kousaie, Shanna; Sheppard, Christine; Taler, Vanessa

2013-01-01

In the brain, resting-state activity refers to non-random patterns of intrinsic activity occurring when participants are not actively engaged in a task. We monitored resting-state activity using electroencephalogram (EEG) both before and after a verbal recognition task. We show a strong positive correlation between accuracy in verbal recognition and pre-task resting-state alpha power at posterior sites. We further characterized this effect by examining resting-state post-task activity. We found marked alterations in resting-state alpha power when comparing pre- and post-task periods, with more pronounced alterations in participants that attained higher task accuracy. These findings support a dynamical view of cognitive processes where patterns of ongoing brain activity can facilitate –or interfere– with optimal task performance. PMID:23785436

Anodal transcranial direct current stimulation over right dorsolateral prefrontal cortex alters decision making during approach-avoidance conflict.

PubMed

Chrysikou, Evangelia G; Gorey, Claire; Aupperle, Robin L

2017-03-01

Approach-avoidance conflict (AAC) refers to situations associated with both rewarding and threatening outcomes. The AAC task was developed to measure AAC decision-making. Approach behavior during this task has been linked to self-reported anxiety sensitivity and has elicited anterior cingulate, insula, caudate and right dorsolateral prefrontal cortex (dlPFC) activity, with right lateral PFC tracking the extent of approach behavior. Guided by these results, we used excitatory transcranial direct current stimulation (tDCS) to demonstrate the causal involvement of right dlPFC in AAC decision-making. Participants received anodal tDCS at 1.5mA over either left or right dlPFC or sham stimulation, while performing the AAC task and a control short-term memory task. Analyses of variance (ANOVA) revealed that for individuals with high anxiety sensitivity excitatory right (but not left or sham) dlPFC stimulation elicited measurable decreases in approach behavior during conflict. Excitatory left (but not right or sham) dlPFC simulation improved performance on the control task. These results support a possible asymmetry between the contributions of right and left dlPFC to AAC resolution during emotional decision-making. Increased activity in right dlPFC may contribute to anxiety-related symptoms and, as such, serve as a neurobehavioral target of anxiolytic treatments aiming to decrease avoidance behavior. © The Author (2016). Published by Oxford University Press.

Volitional control of attention and brain activation in dual task performance.

PubMed

Newman, Sharlene D; Keller, Timothy A; Just, Marcel Adam

2007-02-01

This study used functional MRI (fMRI) to examine the neural effects of willfully allocating one's attention to one of two ongoing tasks. In a dual task paradigm, participants were instructed to focus either on auditory sentence comprehension, mental rotation, or both. One of the major findings is that the distribution of brain activation was amenable to strategic control, such that the amount of activation per task was systematically related to the attention-dividing instructions. The activation in language processing regions was lower when attending to mental rotation than when attending to the sentences, and the activation in visuospatial processing regions was lower when attending to sentences than when attending to mental rotations. Additionally, the activation was found to be underadditive, with the dual-task condition eliciting less activation than the sum of the attend sentence and attend rotation conditions. We also observed a laterality shift across conditions within language-processing regions, with the attend sentence condition showing bilateral activation, while the dual task condition showed a left hemispheric dominance. This shift suggests multiple language-processing modes and may explain the underadditivity in activation observed in the current and previous studies.

The Role of Informative and Ambiguous Feedback in Avoidance Behavior: Empirical and Computational Findings

PubMed Central

Moustafa, Ahmed A.; Sheynin, Jony; Myers, Catherine E.

2015-01-01

Avoidance behavior is a critical component of many psychiatric disorders, and as such, it is important to understand how avoidance behavior arises, and whether it can be modified. In this study, we used empirical and computational methods to assess the role of informational feedback and ambiguous outcome in avoidance behavior. We adapted a computer-based probabilistic classification learning task, which includes positive, negative and no-feedback outcomes; the latter outcome is ambiguous as it might signal either a successful outcome (missed punishment) or a failure (missed reward). Prior work with this task suggested that most healthy subjects viewed the no-feedback outcome as strongly positive. Interestingly, in a later version of the classification task, when healthy subjects were allowed to opt out of (i.e. avoid) responding, some subjects (“avoiders”) reliably avoided trials where there was a risk of punishment, but other subjects (“non-avoiders”) never made any avoidance responses at all. One possible interpretation is that the “non-avoiders” valued the no-feedback outcome so positively on punishment-based trials that they had little incentive to avoid. Another possible interpretation is that the outcome of an avoided trial is unspecified and that lack of information is aversive, decreasing subjects’ tendency to avoid. To examine these ideas, we here tested healthy young adults on versions of the task where avoidance responses either did or did not generate informational feedback about the optimal response. Results showed that provision of informational feedback decreased avoidance responses and also decreased categorization performance, without significantly affecting the percentage of subjects classified as “avoiders.” To better understand these results, we used a modified Q-learning model to fit individual subject data. Simulation results suggest that subjects in the feedback condition adjusted their behavior faster following better

Interrelating Behavioral Measures of Distress Tolerance with Self-Reported Experiential Avoidance.

PubMed

Schloss, Heather M; Haaga, David A F

2011-03-01

Experiential avoidance and distress intolerance play a central role in novel behavior therapies, yet they appear to overlap considerably the REBT concept of low frustration tolerance. Using baseline data from 100 adult cigarette smokers enrolled in a clinical trial of smoking cessation therapies, the present study evaluated the convergent validity of common questionnaire measures of experiential avoidance (Acceptance and Action Questionnaire; AAQ; Hayes et al. 2004, and Avoidance and Inflexibility Scale: AIS; Gifford et al. 2004) and behavioral measures of distress tolerance (computerized Mirror Tracing Persistence Task: MTPT-C: Strong et al. 2003; computerized Paced Auditory Serial Addition Task; PASAT-C; Lejuez et al. 2003). The distress tolerance measures correlated significantly (r = .29) with one another. However, the questionnaire measures of experiential avoidance did not correlate with each other, nor with the behavioral measures. Further research is needed on the validity of measuring experiential avoidance by self-report and of the overlap versus distinctiveness of seemingly similar constructs such as experiential avoidance, distress tolerance, and frustration tolerance.

The Color Red Supports Avoidance Reactions to Unhealthy Food.

PubMed

Rohr, Michaela; Kamm, Friederike; Koenigstorfer, Joerg; Groeppel-Klein, Andrea; Wentura, Dirk

2015-01-01

Empirical evidence suggests that the color red acts like an implicit avoidance cue in food contexts. Thus specific colors seem to guide the implicit evaluation of food items. We built upon this research by investigating the implicit meaning of color (red vs. green) in an approach-avoidance task with healthy and unhealthy food items. Thus, we examined the joint evaluative effects of color and food: Participants had to categorize food items by approach-avoidance reactions, according to their healthfulness. Items were surrounded by task-irrelevant red or green circles. We found that the implicit meaning of the traffic light colors influenced participants' reactions to the food items. The color red (compared to green) facilitated automatic avoidance reactions to unhealthy foods. By contrast, approach behavior toward healthy food items was not moderated by color. Our findings suggest that traffic light colors can act as implicit cues that guide automatic behavioral reactions to food.

Steering Clear: Avoidance in the Production of Idioms.

ERIC Educational Resources Information Center

Irujo, Suzanne

A study of advanced English learners' use or avoidance of English idioms is described. The investigation looked at whether the subjects would attempt to use English idioms in a translation task containing idioms, or would instead use non-idiomatic synonyms or paraphrase. It also looked at which idioms are used and which are avoided: those that are…

Resting-state brain activity in the motor cortex reflects task-induced activity: A multi-voxel pattern analysis.

PubMed

Kusano, Toshiki; Kurashige, Hiroki; Nambu, Isao; Moriguchi, Yoshiya; Hanakawa, Takashi; Wada, Yasuhiro; Osu, Rieko

2015-08-01

It has been suggested that resting-state brain activity reflects task-induced brain activity patterns. In this study, we examined whether neural representations of specific movements can be observed in the resting-state brain activity patterns of motor areas. First, we defined two regions of interest (ROIs) to examine brain activity associated with two different behavioral tasks. Using multi-voxel pattern analysis with regularized logistic regression, we designed a decoder to detect voxel-level neural representations corresponding to the tasks in each ROI. Next, we applied the decoder to resting-state brain activity. We found that the decoder discriminated resting-state neural activity with accuracy comparable to that associated with task-induced neural activity. The distribution of learned weighted parameters for each ROI was similar for resting-state and task-induced activities. Large weighted parameters were mainly located on conjunctive areas. Moreover, the accuracy of detection was higher than that for a decoder whose weights were randomly shuffled, indicating that the resting-state brain activity includes multi-voxel patterns similar to the neural representation for the tasks. Therefore, these results suggest that the neural representation of resting-state brain activity is more finely organized and more complex than conventionally considered.

Nitric oxide facilitates active avoidance learning via enhancement of glutamate levels in the hippocampal dentate gyrus.

PubMed

Wang, Shi; Pan, De-Xi; Wang, Dan; Wan, Peng; Qiu, De-Lai; Jin, Qing-Hua

2014-09-01

The hippocampus is a key structure for learning and memory in mammals, and long-term potentiation (LTP) is an important cellular mechanism responsible for learning and memory. Despite a number of studies indicating that nitric oxide (NO) is involved in the formation and maintenance of LTP as a retrograde messenger, few studies have used neurotransmitter release as a visual indicator in awake animals to explore the role of NO in learning-dependent long-term enhancement of synaptic efficiency. Therefore, in the present study, the effects of l-NMMA (a NO synthase inhibitor) and SNP (a NO donor) on extracellular glutamate (Glu) concentrations and amplitudes of field excitatory postsynaptic potential (fEPSP) were measured in the hippocampal dentate gyrus (DG) region during the acquisition and extinction of active-avoidance behavior in freely-moving conscious rats. In the control group, the extracellular concentration of Glu in the DG was significantly increased during the acquisition of active-avoidance behavior and gradually returned to baseline levels following extinction training. In the experimental group, the change in Glu concentration was significantly reduced by local microinjection of l-NMMA, as was the acquisition of the active-avoidance behavior. In contrast, the change in Glu concentration was significantly enhanced by SNP, and the acquisition of the active-avoidance behavior was significantly accelerated. Furthermore, in all groups, the changes in extracellular Glu were accompanied by corresponding changes in fEPSP amplitude and active-avoidance behavior. Our results suggest that NO in the hippocampal DG facilitates active avoidance learning via enhancements of glutamate levels and synaptic efficiency in rats. Copyright © 2014 Elsevier B.V. All rights reserved.

Higher doses of (+)MK-801 (dizocilpine) induced mortality and procedural but not cognitive deficits in delayed testing in the active place avoidance with reversal on the Carousel.

PubMed

Lobellová, V; Brichtová, E; Petrásek, T; Valeš, K; Stuchlík, A

2015-01-01

Schizophrenia is a devastating disorder affecting 1 % of the world's population. An important role in the study of this disease is played by animal models. Since there is evidence that acute psychotic episodes can have consequences on later cognitive functioning, the present study has investigated the effects of a single systemic application of higher doses of (+)MK-801 (3 mg/kg and 5 mg/kg) to adult male Long-Evans rats from the Institute's breeding colony on delayed testing in the active place avoidance task with reversal on the Carousel (a rotating arena). Besides significant mortality due to the injections, a disruption of procedural functions in active place avoidance, after the dose 5 mg/kg was observed. It was concluded that Long-Evans rats from our breeding colony do not represent a suitable biomodel for studying the effects of single high-dose NMDA antagonists.

The challenges for scientists in avoiding plagiarism.

PubMed

Fisher, E R; Partin, K M

2014-01-01

Although it might seem to be a simple task for scientists to avoid plagiarism and thereby an allegation of research misconduct, assessment of trainees in the Responsible Conduct of Research and recent findings from the National Science Foundation Office of Inspector General regarding plagiarism suggests otherwise. Our experiences at a land-grant academic institution in assisting researchers in avoiding plagiarism are described. We provide evidence from a university-wide multi-disciplinary course that understanding how to avoid plagiarism in scientific writing is more difficult than it might appear, and that a failure to learn the rules of appropriate citation may cause dire consequences. We suggest that new strategies to provide training in avoiding plagiarism are required.

Effect of pregabalin on fear-based conditioned avoidance learning and spatial learning in a mouse model of scopolamine-induced amnesia.

PubMed

Sałat, Kinga; Podkowa, Adrian; Malikowska, Natalia; Trajer, Jędrzej

2017-03-01

Cognitive deficits are one of the frequent symptoms accompanying epilepsy or its treatment. In this study, the effect on cognition of intraperitoneally administered antiepileptic drug, pregabalin (10 mg/kg), was investigated in scopolamine-induced memory-impaired mice in the passive avoidance task and Morris water maze task. The effect of scopolamine and pregabalin on animals' locomotor activity was also studied. In the retention phase of the passive avoidance task, pregabalin reversed memory deficits induced by scopolamine (p < 0.05). During the acquisition phase of the Morris water maze pregabalin-treated memory-impaired mice performed the test with longer escape latencies than the vehicle-treated mice (significant at p < 0.05 on Day 5, and at p < 0.001 on Day 6). There were no differences in this parameter between the scopolamine-treated control group and pregabalin-treated memory-impaired mice, which indicated that pregabalin had no influence on spatial learning in this task. During the probe trial a significant difference (p < 0.05) was observed in terms of the mean number of target crossings between vehicle-treated mice and pregabalin-treated memory-impaired mice but there was no difference between the scopolamine-treated control group and mice treated with pregabalin + scopolamine. Pregabalin did not influence locomotor activity increased by scopolamine. In passive avoidance task, pregabalin reversed learning deficits induced by scopolamine. In the Morris water maze, pregabalin did not influence spatial learning deficits induced by scopolamine. These results are relevant for epileptic patients treated with pregabalin and those who use it for other therapeutic indications (anxiety, pain).

Effect of dual task activity on reaction time in males and females.

PubMed

Kaur, Manjinder; Nagpal, Sangeeta; Singh, Harpreet; Suhalka, M L

2014-01-01

The present study was designed to compare the auditory and visual reaction time on an Audiovisual Reaction Time Machine with the concomitant use of mobile phones in 52 women and 30 men in the age group of 18-40 years. Males showed significantly (p < 0.05) shorter reaction times, both auditory and visual, than females both during single task and multi task performance. But the percentage increase from their respective baseline auditory reaction times, was more in men than women during multitasking, in hand held (24.38% & 18.70% respectively) and hands free modes (36.40% & 18.40% respectively) of the use of cell phone. VRT increased non significantly during multitasking in both the groups. However, the multitasking per se has detrimental effect on the reaction times in both the groups studied. Hence, it should best be avoided in crucial and high attention demanding tasks like driving.

Brain activity during auditory and visual phonological, spatial and simple discrimination tasks.

PubMed

Salo, Emma; Rinne, Teemu; Salonen, Oili; Alho, Kimmo

2013-02-16

We used functional magnetic resonance imaging to measure human brain activity during tasks demanding selective attention to auditory or visual stimuli delivered in concurrent streams. Auditory stimuli were syllables spoken by different voices and occurring in central or peripheral space. Visual stimuli were centrally or more peripherally presented letters in darker or lighter fonts. The participants performed a phonological, spatial or "simple" (speaker-gender or font-shade) discrimination task in either modality. Within each modality, we expected a clear distinction between brain activations related to nonspatial and spatial processing, as reported in previous studies. However, within each modality, different tasks activated largely overlapping areas in modality-specific (auditory and visual) cortices, as well as in the parietal and frontal brain regions. These overlaps may be due to effects of attention common for all three tasks within each modality or interaction of processing task-relevant features and varying task-irrelevant features in the attended-modality stimuli. Nevertheless, brain activations caused by auditory and visual phonological tasks overlapped in the left mid-lateral prefrontal cortex, while those caused by the auditory and visual spatial tasks overlapped in the inferior parietal cortex. These overlapping activations reveal areas of multimodal phonological and spatial processing. There was also some evidence for intermodal attention-related interaction. Most importantly, activity in the superior temporal sulcus elicited by unattended speech sounds was attenuated during the visual phonological task in comparison with the other visual tasks. This effect might be related to suppression of processing irrelevant speech presumably distracting the phonological task involving the letters. Copyright © 2012 Elsevier B.V. All rights reserved.

Changing implicit attitudes toward smoking: results from a web-based approach-avoidance practice intervention.

PubMed

Macy, Jonathan T; Chassin, Laurie; Presson, Clark C; Sherman, Jeffrey W

2015-02-01

Implicit attitudes have been shown to predict smoking behaviors. Therefore, an important goal is the development of interventions to change these attitudes. This study assessed the effects of a web-based intervention on implicit attitudes toward smoking and receptivity to smoking-related information. Smokers (N = 284) were recruited to a two-session web-based study. In the first session, baseline data were collected. Session two contained the intervention, which consisted of assignment to the experimental or control version of an approach-avoidance task and assignment to an anti-smoking or control public service announcement (PSA), and post-intervention measures. Among smokers with less education and with plans to quit, implicit attitudes were more negative for those who completed the approach-avoidance task. Smokers with more education who viewed the anti-smoking PSA and completed the approach-avoidance task spent more time reading smoking-related information. An approach-avoidance task is a potentially feasible strategy for changing implicit attitudes toward smoking and increasing receptivity to smoking-related information.

Task Inventory Construction. Evaluation of the Marine Corps Task Analysis Program. Technical Report No. 14.

ERIC Educational Resources Information Center

Kishi, Akemi

To aid in the construction of effective task analysis inventories, this technical report discusses: (1) an optimum questionnaire length that adequately covers Marine tasks without unduly fatiguing respondents; (2) procedures for the phrasing of task statements to avoid ambiguities and be understandable to as broad a range of Marines as is…

Active avoidance learning requires prefrontal suppression of amygdala-mediated defensive reactions.

PubMed

Moscarello, Justin M; LeDoux, Joseph E

2013-02-27

Signaled active avoidance (AA) paradigms train subjects to prevent an aversive outcome by performing a learned behavior during the presentation of a conditioned cue. This complex form of conditioning involves pavlovian and instrumental components, which produce competing behavioral responses that must be reconciled for the subject to successfully avoid an aversive stimulus. In signaled AA paradigm for rat, we tested the hypothesis that the instrumental component of AA training recruits infralimbic prefrontal cortex (ilPFC) to inhibit central amygdala (CeA)-mediated Pavlovian reactions. Pretraining lesions of ilPFC increased conditioned freezing while causing a corresponding decrease in avoidance; lesions of CeA produced opposite effects, reducing freezing and facilitating avoidance behavior. Pharmacological inactivation experiments demonstrated that ilPFC is relevant to both acquisition and expression phases of AA learning. Inactivation experiments also revealed that AA produces an ilPFC-mediated diminution of pavlovian reactions that extends beyond the training context, even when the conditioned stimulus is presented in an environment that does not allow the avoidance response. Finally, injection of a protein synthesis inhibitor into either ilPFC or CeA impaired or facilitated AA, respectively, showing that avoidance training produces two opposing memory traces in these regions. These data support a model in which AA learning recruits ilPFC to inhibit CeA-mediated defense behaviors, leading to a robust suppression of freezing that generalizes across environments. Thus, ilPFC functions as an inhibitory interface, allowing instrumental control over an aversive outcome to attenuate the expression of freezing and other reactions to conditioned threat.

From "rest" to language task: Task activation selects and prunes from broader resting-state network.

PubMed

Doucet, Gaelle E; He, Xiaosong; Sperling, Michael R; Sharan, Ashwini; Tracy, Joseph I

2017-05-01

Resting-state networks (RSNs) show spatial patterns generally consistent with networks revealed during cognitive tasks. However, the exact degree of overlap between these networks has not been clearly quantified. Such an investigation shows promise for decoding altered functional connectivity (FC) related to abnormal language functioning in clinical populations such as temporal lobe epilepsy (TLE). In this context, we investigated the network configurations during a language task and during resting state using FC. Twenty-four healthy controls, 24 right and 24 left TLE patients completed a verb generation (VG) task and a resting-state fMRI scan. We compared the language network revealed by the VG task with three FC-based networks (seeding the left inferior frontal cortex (IFC)/Broca): two from the task (ON, OFF blocks) and one from the resting state. We found that, for both left TLE patients and controls, the RSN recruited regions bilaterally, whereas both VG-on and VG-off conditions produced more left-lateralized FC networks, matching more closely with the activated language network. TLE brings with it variability in both task-dependent and task-independent networks, reflective of atypical language organization. Overall, our findings suggest that our RSN captured bilateral activity, reflecting a set of prepotent language regions. We propose that this relationship can be best understood by the notion of pruning or winnowing down of the larger language-ready RSN to carry out specific task demands. Our data suggest that multiple types of network analyses may be needed to decode the association between language deficits and the underlying functional mechanisms altered by disease. Hum Brain Mapp 38:2540-2552, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Antecedents of Approach-Avoidance Achievement Goal Adoption: An Analysis of Two Physical Education Activities

ERIC Educational Resources Information Center

Warburton, Victoria; Spray, Christopher

2013-01-01

The purpose of this study was to determine the relationship between implicit theories of ability and competence perceptions to changes in approach-avoidance goal adoption in two specific activities in the curriculum. Four hundred and thirty pupils, aged 11-15 years, completed measures of approach-avoidance goals, perceived competence and implicit…

Increased experience amplifies the activation of task-irrelevant category representations.

PubMed

Wu, Rachel; Pruitt, Zoe; Zinszer, Benjamin D; Cheung, Olivia S

2017-02-01

Prior research has demonstrated the benefits (i.e., task-relevant attentional selection) and costs (i.e., task-irrelevant attentional capture) of prior knowledge on search for an individual target or multiple targets from a category. This study investigated whether the level of experience with particular categories predicts the degree of task-relevant and task-irrelevant activation of item and category representations. Adults with varying levels of dieting experience (measured via 3 subscales of Disinhibition, Restraint, Hunger; Stunkard & Messick, Journal of Psychosomatic Research, 29(1), 71-83, 1985) searched for targets defined as either a specific food item (e.g., carrots), or a category (i.e., any healthy or unhealthy food item). Apart from the target-present trials, in the target-absent "foil" trials, when searching for a specific item (e.g., carrots), irrelevant items from the target's category (e.g., squash) were presented. The ERP (N2pc) results revealed that the activation of task-relevant representations (measured via Exemplar and Category N2pc amplitudes) did not differ based on the degree of experience. Critically, however, increased dieting experience, as revealed by lower Disinhibition scores, predicted activation of task-irrelevant representations (i.e., attentional capture of foils from the target item category). Our results suggest that increased experience with particular categories encourages the rapid activation of category representations even when category information is task irrelevant, and that the N2pc in foil trials could potentially serve as an indication of experience level in future studies on categorization.

Influence of dorsolateral prefrontal cortex and ventral striatum on risk avoidance in addiction: a mediation analysis.

PubMed

Yamamoto, Dorothy J; Woo, Choong-Wan; Wager, Tor D; Regner, Michael F; Tanabe, Jody

2015-04-01

Alterations in frontal and striatal function are hypothesized to underlie risky decision making in drug users, but how these regions interact to affect behavior is incompletely understood. We used mediation analysis to investigate how prefrontal cortex and ventral striatum together influence risk avoidance in abstinent drug users. Thirty-seven abstinent substance-dependent individuals (SDI) and 43 controls underwent fMRI while performing a decision-making task involving risk and reward. Analyses of a priori regions-of-interest tested whether activity in dorsolateral prefrontal cortex (DLPFC) and ventral striatum (VST) explained group differences in risk avoidance. Whole-brain analysis was conducted to identify brain regions influencing the negative VST-risk avoidance relationship. Right DLPFC (RDLPFC) positively mediated the group-risk avoidance relationship (p < 0.05); RDLPFC activity was higher in SDI and predicted higher risk avoidance across groups, controlling for SDI vs. Conversely, VST activity negatively influenced risk avoidance (p < 0.05); it was higher in SDI, and predicted lower risk avoidance. Whole-brain analysis revealed that, across group, RDLPFC and left temporal-parietal junction positively (p ≤ 0.001) while right thalamus and left middle frontal gyrus negatively (p < 0.005) mediated the VST activity-risk avoidance relationship. RDLPFC activity mediated less risky decision making while VST mediated more risky decision making across drug users and controls. These results suggest a dual pathway underlying decision making, which, if imbalanced, may adversely influence choices involving risk. Modeling contributions of multiple brain systems to behavior through mediation analysis could lead to a better understanding of mechanisms of behavior and suggest neuromodulatory treatments for addiction. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Influence of dorsolateral prefrontal cortex and ventral striatum on risk avoidance in addiction: a mediation analysis*

PubMed Central

Yamamoto, Dorothy J.; Woo, Choong-Wan; Wager, Tor D.; Regner, Michael F.; Tanabe, Jody

2015-01-01

Background Alterations in frontal and striatal function are hypothesized to underlie risky decision-making in drug users, but how these regions interact to affect behavior is incompletely understood. We used mediation analysis to investigate how prefrontal cortex and ventral striatum together influence risk avoidance in abstinent drug users. Method Thirty-seven abstinent substance-dependent individuals (SDI) and 43 controls underwent fMRI while performing a decision-making task involving risk and reward. Analyses of a priori regions-of-interest tested whether activity in dorsolateral prefrontal cortex (DLPFC) and ventral striatum (VST) explained group differences in risk avoidance. Whole-brain analysis was conducted to identify brain regions influencing the negative VST-risk avoidance relationship. Results Right DLPFC (RDLPFC) positively mediated the group-risk avoidance relationship (p < 0.05); RDLPFC activity was higher in SDI and predicted higher risk avoidance across groups, controlling for SDI vs. controls. Conversely, VST activity negatively influenced risk avoidance (p < 0.05); it was higher in SDI, and predicted lower risk avoidance. Whole-brain analysis revealed that, across group, RDLPFC and left temporal-parietal junction positively (p ≤ 0.001) while right thalamus and left middle frontal gyrus negatively (p < 0.005) mediated the VST activity-risk avoidance relationship. Conclusion RDLPFC activity mediated less risky decision-making while VST mediated more risky decision-making across drug users and controls. These results suggest a dual pathway underlying decision-making, which, if imbalanced, may adversely influence choices involving risk. Modeling contributions of multiple brain systems to behavior through mediation analysis could lead to a better understanding of mechanisms of behavior and suggest neuromodulatory treatments for addiction. PMID:25736619

Anxiety, not anger, induces inflammatory activity: An avoidance/approach model of immune system activation.

PubMed

Moons, Wesley G; Shields, Grant S

2015-08-01

Psychological stressors reliably trigger systemic inflammatory activity as indexed by levels of proinflammatory cytokines. This experiment demonstrates that one's specific emotional reaction to a stressor may be a significant determinant of whether an inflammatory reaction occurs in response to that stressor. Based on extant correlational evidence and theory, a causal approach was used to determine whether an avoidant emotion (anxiety) triggers more inflammatory activity than an approach emotion (anger). In an experimental design (N = 40), a 3-way Emotion Condition × Time × Analyte interaction revealed that a writing-based anxiety induction, but not a writing-based anger induction, increased mean levels of interferon-γ (IFN- γ) and interleukin-1β (IL-1β), but not interleukin-6 (IL-6) in oral mucous, F(2, 54) = 4.64, p = .01, ηp(²) = .15. Further, self-reported state anxiety predicted elevated levels of proinflammatory cytokines, all ΔR(²) >.06, ps <.04, but self-reported state anger did not. These results constitute the first evidence to our knowledge that specific negative emotions can differentially cause inflammatory activity and support a theoretical model explaining these effects based on the avoidance or approach motivations associated with emotions. (c) 2015 APA, all rights reserved).

Gender differences in brain activation on a mental rotation task.

PubMed

Semrud-Clikeman, Margaret; Fine, Jodene Goldenring; Bledsoe, Jesse; Zhu, David C

2012-10-01

Few neuroimaging studies have explored gender differences on mental rotation tasks. Most studies have utilized samples with both genders, samples mainly consisting of men, or samples with six or fewer females. Graduate students in science fields or liberal arts programs (20 males, 20 females) completed a mental rotation task during functional magnetic resonance imaging (fMRI). When a pair of cube figures was shown, the participant made a keypad response based on whether the pair is the same/similar or different. Regardless of gender, the bilateral middle frontal gyrus, bilateral intraparietal sulcus (IPS), and the left precuneus were activated when a subject tried to solve the mental rotation task. Increased activation in the right inferior frontal gyrus/middle frontal gyrus, the left precuneus/posterior cingulate cortex/cuneus region, and the left middle occipital gyrus was found for men as compared to women. Better accuracy and shorter response times were correlated with an increased activation in the bilateral intraparietal sulcus. No significant brain activity differences related to mental rotation were found between academic majors. These findings suggest that networks involved in visual attention appear to be more strongly activated in the mental rotation tasks in men as compared to women. It also suggests that men use a more automatic process when analyzing complex visual reasoning tasks while women use a more top-down process.

Predictors and outcome of pain-related avoidance of activities in persons with early symptomatic knee osteoarthritis: a five-year followup study.

PubMed

Holla, Jasmijn F M; van der Leeden, Marike; Knol, Dirk L; Roorda, Leo D; Hilberdink, Wim K H A; Lems, Willem F; Steultjens, Martijn P M; Dekker, Joost

2015-01-01

It has been hypothesized that pain and low vitality lead to an increase in avoidance of activities in persons with early symptomatic knee osteoarthritis (OA), and that avoidance of activities leads to an increase in activity limitations. The present study aimed to evaluate these hypotheses. Baseline, 2-year, and 5-year followup data of 828 participants from the Cohort Hip and Cohort Knee Study with early symptomatic knee OA were used. Autoregressive generalized estimating equations and linear regression models were used to analyze the longitudinal and cross-sectional associations between self-reported knee pain, vitality, pain-related avoidance of activities, and activity limitations. The models were adjusted for the covariates age, sex, education level, body mass index, comorbidity, radiographic severity, and hip pain. In longitudinal analyses, knee pain and vitality predicted a subsequent increase in avoidance of activities. Pain-related avoidance of activities predicted a subsequent increase in activity limitations; however, this relationship lost statistical significance (P = 0.089) after adjustment for covariates. Cross-sectional analyses showed strong relationships between knee pain, low vitality, pain-related avoidance of activities, and activity limitations at all time points. In persons with early symptomatic knee OA, knee pain and low vitality lead to a subsequent increase in avoidance of activities. Pain-related avoidance of activities is related to activity limitations at inception of symptoms, but also years later. Therefore, it can be recommended to monitor and target avoidance of activities at various stages of the disease. Copyright © 2015 by the American College of Rheumatology.

Task Analysis of Shuttle Entry and Landing Activities

NASA Technical Reports Server (NTRS)

Holland, Albert W.; Vanderark, Stephen T.

1993-01-01

The Task Analysis of Shuttle Entry and Landing (E/L) Activities documents all tasks required to land the Orbiter following an STS mission. In addition to analysis of tasks performed, task conditions are described, including estimated time for completion, altitude, relative velocity, normal and lateral acceleration, location of controls operated or monitored, and level of g's experienced. This analysis precedes further investigations into potential effects of zero g on piloting capabilities for landing the Orbiter following long-duration missions. This includes, but is not limited to, researching the effects of extended duration missions on piloting capabilities. Four primary constraints of the analysis must be clarified: (1) the analysis depicts E/L in a static manner--the actual process is dynamic; (2) the task analysis was limited to a paper analysis, since it was not feasible to conduct research in the actual setting (i.e., observing or filming duration an actual E/L); (3) the tasks included are those required for E/L during nominal, daylight conditions; and (4) certain E/L tasks will vary according to the flying style of each commander.

Experimental Studies Of Pilot Performance At Collision Avoidance During Closely Spaced Parallel Approaches

NASA Technical Reports Server (NTRS)

Pritchett, Amy R.; Hansman, R. John

1997-01-01

Efforts to increase airport capacity include studies of aircraft systems that would enable simultaneous approaches to closely spaced parallel runway in Instrument Meteorological Conditions (IMC). The time-critical nature of a parallel approach results in key design issues for current and future collision avoidance systems. Two part-task flight simulator studies have examined the procedural and display issues inherent in such a time-critical task, the interaction of the pilot with a collision avoidance system, and the alerting criteria and avoidance maneuvers preferred by subjects.

Interrelating Behavioral Measures of Distress Tolerance with Self-Reported Experiential Avoidance

PubMed Central

Schloss, Heather M.

2011-01-01

Experiential avoidance and distress intolerance play a central role in novel behavior therapies, yet they appear to overlap considerably the REBT concept of low frustration tolerance. Using baseline data from 100 adult cigarette smokers enrolled in a clinical trial of smoking cessation therapies, the present study evaluated the convergent validity of common questionnaire measures of experiential avoidance (Acceptance and Action Questionnaire; AAQ; Hayes et al. 2004, and Avoidance and Inflexibility Scale: AIS; Gifford et al. 2004) and behavioral measures of distress tolerance (computerized Mirror Tracing Persistence Task: MTPT-C: Strong et al. 2003; computerized Paced Auditory Serial Addition Task; PASAT-C; Lejuez et al. 2003). The distress tolerance measures correlated significantly (r = .29) with one another. However, the questionnaire measures of experiential avoidance did not correlate with each other, nor with the behavioral measures. Further research is needed on the validity of measuring experiential avoidance by self-report and of the overlap versus distinctiveness of seemingly similar constructs such as experiential avoidance, distress tolerance, and frustration tolerance. PMID:21448252

The Effects of Task Fluency and Concurrent Reinforcement Schedules on Student Choice Allocation between Math Tasks

ERIC Educational Resources Information Center

Zaman, Maliha

2010-01-01

Students may avoid working on difficult tasks because it takes them longer to complete those tasks, which results in a delay to reinforcement. Research studies show that reinforcer and response dimensions can be manipulated within a concurrent operants framework to bias choice allocation toward more difficult tasks. The current study extends…

Context-dependent activation of reduced autobiographical memory specificity as an avoidant coping style.

PubMed

Debeer, Elise; Raes, Filip; Williams, J Mark G; Hermans, Dirk

2011-12-01

According to the affect-regulation hypothesis (Williams et al., 2007), reduced autobiographical memory specificity (rAMS) or overgeneral memory (OGM) might be considered a cognitive avoidance strategy; that is, people learn to avoid the emotionally painful consequences associated with the retrieval of specific negative memories. Based on this hypothesis, one would predict significant negative associations between AMS and avoidant coping. However, studies investigating this prediction have led to equivocal results. In the present study we tested a possible explanation for these contradictory findings. It was hypothesized that rAMS (in part) reflects an avoidant coping strategy, which might only become apparent under certain conditions, that is, conditions that signal the possibility of 'danger.' To test this hypothesis, we assessed AMS and behavioral avoidance but experimentally manipulated the instructions. In the neutral condition, two parallel versions of the Autobiographical Memory Test (AMT) were presented under neutral instructions. In the threat condition, the first AMT was presented under neutral instructions, while the second AMT was presented under 'threat instructions.' Results showed no significant correlations between avoidance and OGM under neutral conditions but significant and markedly stronger correlations under threat conditions, with more avoidance being associated with fewer specific and more categoric memories. In addition, high avoiders showed a stronger reduction in AMS in the threat condition as compared with the neutral condition, while low avoiders showed no such difference between conditions. The data confirm that OGM can be considered as part of a broader avoidant coping style. However, more importantly, they show that, at least in nonclinical individuals, the activation of this coping style may depend on the context. (c) 2011 APA, all rights reserved.

Active controllers and the time duration to learn a task

NASA Technical Reports Server (NTRS)

Repperger, D. W.; Goodyear, C.

1986-01-01

An active controller was used to help train naive subjects involved in a compensatory tracking task. The controller is called active in this context because it moves the subject's hand in a direction to improve tracking. It is of interest here to question whether the active controller helps the subject to learn a task more rapidly than the passive controller. Six subjects, inexperienced to compensatory tracking, were run to asymptote root mean square error tracking levels with an active controller or a passive controller. The time required to learn the task was defined several different ways. The results of the different measures of learning were examined across pools of subjects and across controllers using statistical tests. The comparison between the active controller and the passive controller as to their ability to accelerate the learning process as well as reduce levels of asymptotic tracking error is reported here.

Changing Implicit Attitudes toward Smoking: Results from a Web-Based Approach-Avoidance Practice Intervention

PubMed Central

Macy, Jonathan T.; Chassin, Laurie; Presson, Clark C.; Sherman, Jeffrey W.

2014-01-01

Implicit attitudes have been shown to predict smoking behaviors. Therefore, an important goal is the development of interventions to change these attitudes. This study assessed the effects of a web-based intervention on implicit attitudes toward smoking and receptivity to smoking-related information. Smokers (N=284) were recruited to a two-session web-based study. In the first session, baseline data were collected. Session two contained the intervention, which consisted of assignment to the experimental or control version of an approach-avoidance task and assignment to an anti-smoking or control public service announcement (PSA), and post-intervention measures. Among smokers with less education and with plans to quit, implicit attitudes were more negative for those who completed the approach-avoidance task. Smokers with more education who viewed the anti-smoking PSA and completed the approach-avoidance task spent more time reading smoking-related information. An approach-avoidance task is a potentially feasible strategy for changing implicit attitudes toward smoking and increasing receptivity to smoking-related information. PMID:25059750

The Influence of Depression on Cognitive Control: Disambiguating Approach and Avoidance Tendencies.

PubMed

Huang, He; Movellan, Javier; Paulus, Martin P; Harlé, Katia M

2015-01-01

Dysfunctions of approach and avoidance motivation play an important role in depression, which in turn may affect cognitive control, i.e., the ability to regulate thoughts and action to achieve internal goals. We use a novel experimental paradigm, i.e. a computer simulated driving-task, to study the impact of depression on cognitive control by measuring approach and avoidance actions in continuous time. In this task, 39 subjects with minimal to severe depression symptoms were instructed to use a joystick to move a virtual car as quickly as possible to a target point without crossing a stop-sign or crashing into a wall. We recorded their continuous actions on a joystick and found that depression 1) leads to further stopping distance to task target; and 2) increases the magnitude of late deceleration (avoidance) but not early acceleration (approach), which was only observed in the stop-sign condition. Taken together, these results are consistent with the hypothesis that depressed individuals have greater avoidance motivation near stopping target, but are minimally affected by approach motivation.

How to Avoid Stereotypes? Evaluation of a Strategy based on Self-Regulatory Processes.

PubMed

Aranda, María; Montes-Berges, Beatriz

2016-06-10

Based on research on the motivational processes involved in preventing and controlling stereotypes, we aimed to assess whether temporary activation of egalitarian goals - by means of a task that gives respondents exposure to a text on gender inequality - can prevent stereotyped answers on the task. The task asks participants to place women and men into a hierarchical organizational structure. Two specific objectives were established: first, to control the effect of prejudice and egalitarian commitment on the dependent variable; and second, to study gender differences in task responses. The study included 474 college students, 153 men and 321 women. Their mean age was 20.04 (SD = 4.43). ANCOVA indicated main effects of condition, F(1) = 4.15, p = .042, η2 = .081 (control condition without goal activation vs. experimental condition with goal activation) and sex, F(1) = 40.46, p < .001, η2 = .081, on the dependent variable (female candidates placed in the chart). Specifically, responses from participants in the experimental condition avoided stereotyped answers more than participants in the control condition. Furthermore, women's performance on the task was more egalitarian than men's. Finally, there was a significant interaction effect of condition and type of organization, F(2) = 3.97, p = .019, η2 = .017; participants assigning candidates to the feminized organization differed the most across conditions.

Task-Driven Activity Reduces the Cortical Activity Space of the Brain: Experiment and Whole-Brain Modeling

PubMed Central

Hagmann, Patric; Deco, Gustavo

2015-01-01

How a stimulus or a task alters the spontaneous dynamics of the brain remains a fundamental open question in neuroscience. One of the most robust hallmarks of task/stimulus-driven brain dynamics is the decrease of variability with respect to the spontaneous level, an effect seen across multiple experimental conditions and in brain signals observed at different spatiotemporal scales. Recently, it was observed that the trial-to-trial variability and temporal variance of functional magnetic resonance imaging (fMRI) signals decrease in the task-driven activity. Here we examined the dynamics of a large-scale model of the human cortex to provide a mechanistic understanding of these observations. The model allows computing the statistics of synaptic activity in the spontaneous condition and in putative tasks determined by external inputs to a given subset of brain regions. We demonstrated that external inputs decrease the variance, increase the covariances, and decrease the autocovariance of synaptic activity as a consequence of single node and large-scale network dynamics. Altogether, these changes in network statistics imply a reduction of entropy, meaning that the spontaneous synaptic activity outlines a larger multidimensional activity space than does the task-driven activity. We tested this model’s prediction on fMRI signals from healthy humans acquired during rest and task conditions and found a significant decrease of entropy in the stimulus-driven activity. Altogether, our study proposes a mechanism for increasing the information capacity of brain networks by enlarging the volume of possible activity configurations at rest and reliably settling into a confined stimulus-driven state to allow better transmission of stimulus-related information. PMID:26317432

An architecture for intelligent task interruption

NASA Technical Reports Server (NTRS)

Sharma, D. D.; Narayan, Srini

1990-01-01

In the design of real time systems the capability for task interruption is often considered essential. The problem of task interruption in knowledge-based domains is examined. It is proposed that task interruption can be often avoided by using appropriate functional architectures and knowledge engineering principles. Situations for which task interruption is indispensable, a preliminary architecture based on priority hierarchies is described.

The tipping point: Value differences and parallel dorsal-ventral frontal circuits gating human approach-avoidance behavior.

PubMed

Schlund, Michael W; Brewer, Adam T; Magee, Sandy K; Richman, David M; Solomon, Scott; Ludlum, MaDonna; Dymond, Simon

2016-08-01

Excessive avoidance and diminished approach behavior are both prominent features of anxiety, trauma and stress related disorders. Despite this, little is known about the neuronal mechanisms supporting gating of human approach-avoidance behavior. Here, we used functional magnetic resonance imaging (fMRI) to track dorsal anterior cingulate and medial prefrontal (dACC/dmPFC) activation along an approach-avoidance continuum to assess sensitivity to competing appetitive and aversive contingencies and correspondence with behavior change. Behavioral and fMRI experiments were conducted using a novel approach-avoidance task where a monetary reward appeared in the presence of a conditioned stimulus (CS), or threat, that signaled increasing probability of unconditioned stimulus (US) delivery. Approach produced the reward or probabilistic US, while avoidance prevented US delivery, and across trials, reward remained fixed while the CS threat level varied unpredictably. Increasing the CS threat level (i.e., US probability) produced the desired approach-avoidance transition and inverted U-shaped changes in decision times, electrodermal activity and activation in pregenual ACC, dACC/dmPFC, striatum, anterior insula and inferior frontal regions. Conversely, U-shaped changes in activation were observed in dorsolateral and ventromedial prefrontal cortex and bimodal changes in the orbitofrontal and ventral hippocampus. These new results show parallel dorsal-ventral frontal circuits support gating of human approach-avoidance behavior where dACC/dmPFC signals inversely correlate with value differences between approach and avoidance contingencies while ventral frontal signals correlate with the value of predictable outcomes. Our findings provide an important bridge between basic research on brain mechanisms of value-guided decision-making and value-focused clinical theories of anxiety and related interventions. Published by Elsevier Inc.

The dense core vesicle protein IA-2, but not IA-2β, is required for active avoidance learning.

PubMed

Carmona, G N; Nishimura, T; Schindler, C W; Panlilio, L V; Notkins, A L

2014-06-06

The islet-antigens IA-2 and IA-2β are major autoantigens in type-1 diabetes and transmembrane proteins in dense core vesicles (DCV). Recently we showed that deletion of both IA-2 and IA-2β alters the secretion of hormones and neurotransmitters and impairs behavior and learning. The present study was designed to evaluate the contribution to learning of each of these genes by using single knockout (SKO) and double knockout (DKO) mice in an active avoidance test. After 5 days of training, wild-type (WT) mice showed 60-70% active avoidance responses, whereas the DKO mice showed only 10-15% active avoidance responses. The degree of active avoidance responses in the IA-2 SKO mice was similar to that of the DKO mice, but in contrast, the IA-2β SKO mice behaved like WT mice showing 60-70% active avoidance responses. Molecular studies revealed a marked decrease in the phosphorylation of the cAMP response element-binding protein (CREB) and Ca(2+)/calmodulin-dependent protein kinase II (CAMKII) in the striatum and hippocampus of the IA-2 SKO and DKO mice, but not in the IA-2β SKO mice. To evaluate the role of CREB and CAMKII in the SKO and DKO mice, GBR-12909, which selectively blocks the dopamine uptake transporter and increases CREB and CAMKII phosphorylation, was administered. GBR-12909 restored the phosphorylation of CREB and CAMKII and increased active avoidance learning in the DKO and IA-2 SKO to near the normal levels found in the WT and IA-2β SKO mice. We conclude that in the absence of the DCV protein IA-2, active avoidance learning is impaired. Published by Elsevier Ltd.

Perspective traffic display format and airline pilot traffic avoidance

NASA Technical Reports Server (NTRS)

Ellis, Stephen R.; Mcgreevy, Michael W.; Hitchcock, Robert J.

1987-01-01

Part-task experiments have examined perspective projections of cockpit displays of traffic information as a means of presenting aircraft separation information to airline pilots. Ten airline pilots served as subjects in an experiment comparing the perspective projection with plan-view projections of the same air traffic situations. The pilots' task was to monitor the traffic display in order to decide if an avoidance maneuver was needed. Pilots took more time to select avoidance maneuvers with a conventional plan-view display than with an experimental perspective display. In contrast to previous results, if the pilots selected a maneuver with the perspective display, they were more likely to choose one with a vertical component. Tabulation of the outcomes of their initial avoidance decisions with both perspective and plan-view displays showed that they were more likely to achieve required separation with maneuvers chosen with the aid of perspective displays.

Time pressure undermines performance more under avoidance than approach motivation.

PubMed

Roskes, Marieke; Elliot, Andrew J; Nijstad, Bernard A; De Dreu, Carsten K W

2013-06-01

Four experiments were designed to test the hypothesis that performance is particularly undermined by time pressure when people are avoidance motivated. The results supported this hypothesis across three different types of tasks, including those well suited and those ill suited to the type of information processing evoked by avoidance motivation. We did not find evidence that stress-related emotions were responsible for the observed effect. Avoidance motivation is certainly necessary and valuable in the self-regulation of everyday behavior. However, our results suggest that given its nature and implications, it seems best that avoidance motivation is avoided in situations that involve (time) pressure.

Brain Activations for Vestibular Stimulation and Dual Tasking Change with Spaceflight

NASA Technical Reports Server (NTRS)

Yuan, Peng; Koppelmans, Vincent; Reuter-Lorenz, Patricia; De Dios, Yiri; Gadd, Nichole; Wood, Scott; Riascos, Roy; Kofman, Igor; Bloomberg, Jacob; Mulavara, Ajitkumar;

Unique and Persistent Individual Patterns of Brain Activity Across Different Memory Retrieval Tasks

PubMed Central

Miller, Michael B.; Donovan, Christa-Lynn; Van Horn, John D.; German, Elaine; Sokol-Hessner, Peter; Wolford, George L.

2009-01-01

Fourteen subjects were scanned in two fMRI sessions separated by several months. During each session, subjects performed an episodic retrieval task, a semantic retrieval task, and a working memory task. We found that 1) despite extensive intersubject variability in the pattern of activity across the whole brain, individual activity patterns were stable over time, 2) activity patterns of the same individual performing different tasks were more similar than activity patterns of different individuals performing the same task, and 3) that individual differences in decision criterion on a recognition test predicted the degree of similarity between any two individuals’ patterns of brain activity, but individual differences in memory accuracy or similarity in structural anatomy did not. These results imply that the exclusive use of group maps may be ineffective in profiling the pattern of activations for a given task. This may be particularly true for a task like episodic retrieval, which is relatively strategic and can involve widely-distributed specialized processes that are peripheral to the actual retrieval of stored information. Further, these processes may be differentially engaged depending on individual differences in cognitive processing and/or physiology. PMID:19540922

Examining the Role of the Human Hippocampus in Approach-Avoidance Decision Making Using a Novel Conflict Paradigm and Multivariate Functional Magnetic Resonance Imaging.

PubMed

O'Neil, Edward B; Newsome, Rachel N; Li, Iris H N; Thavabalasingam, Sathesan; Ito, Rutsuko; Lee, Andy C H

2015-11-11

Rodent models of anxiety have implicated the ventral hippocampus in approach-avoidance conflict processing. Few studies have, however, examined whether the human hippocampus plays a similar role. We developed a novel decision-making paradigm to examine neural activity when participants made approach/avoidance decisions under conditions of high or absent approach-avoidance conflict. Critically, our task required participants to learn the associated reward/punishment values of previously neutral stimuli and controlled for mnemonic and spatial processing demands, both important issues given approach-avoidance behavior in humans is less tied to predation and foraging compared to rodents. Participants played a points-based game where they first attempted to maximize their score by determining which of a series of previously neutral image pairs should be approached or avoided. During functional magnetic resonance imaging, participants were then presented with novel pairings of these images. These pairings consisted of images of congruent or opposing learned valences, the latter creating conditions of high approach-avoidance conflict. A data-driven partial least squares multivariate analysis revealed two reliable patterns of activity, each revealing differential activity in the anterior hippocampus, the homolog of the rodent ventral hippocampus. The first was associated with greater hippocampal involvement during trials with high as opposed to no approach-avoidance conflict, regardless of approach or avoidance behavior. The second pattern encompassed greater hippocampal activity in a more anterior aspect during approach compared to avoid responses, for conflict and no-conflict conditions. Multivoxel pattern classification analyses yielded converging findings, underlining a role of the anterior hippocampus in approach-avoidance conflict decision making. Approach-avoidance conflict has been linked to anxiety and occurs when a stimulus or situation is associated with reward

Enhanced Avoidance Habits in Obsessive-Compulsive Disorder

PubMed Central

Gillan, Claire M.; Morein-Zamir, Sharon; Urcelay, Gonzalo P.; Sule, Akeem; Voon, Valerie; Apergis-Schoute, Annemieke M.; Fineberg, Naomi A.; Sahakian, Barbara J.; Robbins, Trevor W.

2014-01-01

Background Obsessive-compulsive disorder (OCD) is a psychiatric condition that typically manifests in compulsive urges to perform irrational or excessive avoidance behaviors. A recent account has suggested that compulsivity in OCD might arise from excessive stimulus-response habit formation, rendering behavior insensitive to goal value. We tested if OCD patients have a bias toward habits using a novel shock avoidance task. To explore how habits, as a putative model of compulsivity, might relate to obsessions and anxiety, we recorded measures of contingency knowledge, explicit fear, and physiological arousal. Methods Twenty-five OCD patients and 25 control subjects completed a shock avoidance task designed to induce habits through overtraining, which were identified using goal-devaluation. The relationship between habitual behavior, erroneous cognitions, and physiological arousal was assessed using behavior, questionnaires, subjective report, and skin conductance responses. Results A devaluation sensitivity test revealed that both groups could inhibit unnecessary behavioral responses before overtraining. Following overtraining, OCD patients showed greater avoidance habits than control subjects. Groups did not differ in conditioned arousal (skin conductance responses) at any stage. Additionally, groups did not differ in contingency knowledge or explicit ratings of shock expectancy following the habit test. Habit responses were associated with a subjective urge to respond. Conclusions These data indicate that OCD patients have a tendency to develop excessive avoidance habits, providing support for a habit account of OCD. Future research is needed to fully characterize the causal role of physiological arousal and explicit fear in habit formation in OCD. PMID:23510580

Life-threatening event reduces subjective well-being through activating avoidance motivation: a longitudinal study.

PubMed

Van Dijk, Dina; Seger-Guttmann, Tali; Heller, Daniel

2013-04-01

Drawing on the approach-avoidance theory, we have examined the role of avoidance motivation in explaining the negative effects of a life-threatening event on subjective well-being (SWB). Residents of the south of Israel were surveyed during heavy missile attacks in January 2009 (T1; n = 283), and again after 6 months (T2; n = 212) and 1 year (T3; n = 154). During the missile attacks, we also surveyed a group from the center of the country (T1; n = 102), not exposed to the attacks. The results indicate that avoidance motivation was activated by the life threat and further mediated its detrimental influence on SWB measures (positive/negative affects, anxiety, and subjective health). Moreover, within the southern sample, the drop in avoidance motivation over time mediated the parallel drop in SWB. In contrast to avoidance motivation, approach motivation remained stable over time and was related to positive emotions. The role of avoidance and approach motivations in life-threatening situations is further discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Increased subcortical neural activity among HIV+ individuals during a lexical retrieval task.

PubMed

Thames, April D; Sayegh, Philip; Terashima, Kevin; Foley, Jessica M; Cho, Andrew; Arentoft, Alyssa; Hinkin, Charles H; Bookheimer, Susan Y

2016-08-01

Deficits in lexical retrieval, present in approximately 40% of HIV+ patients, are thought to reflect disruptions to frontal-striatal functions and may worsen with immunosuppression. Coupling frontal-striatal tasks such as lexical retrieval with functional neuroimaging may help delineate the pathophysiologic mechanisms underlying HIV-associated neurological dysfunction. We examined whether HIV infection confers brain functional changes during lexical access and retrieval. It was expected that HIV+ individuals would demonstrate greater brain activity in frontal-subcortical regions despite minimal differences between groups on neuropsychological testing. Within the HIV+ sample, we examined associations between indices of immunosuppression (recent and nadir CD4+ count) and task-related signal change in frontostriatal structures. Method16 HIV+ participants and 12 HIV- controls underwent fMRI while engaged in phonemic/letter and semantic fluency tasks. Participants also completed standardized measures of verbal fluency HIV status groups performed similarly on phonemic and semantic fluency tasks prior to being scanned. fMRI results demonstrated activation differences during the phonemic fluency task as a function of HIV status, with HIV+ individuals demonstrating significantly greater activation in BG structures than HIV- individuals. There were no significant differences in frontal brain activation between HIV status groups during the phonemic fluency task, nor were there significant brain activation differences during the semantic fluency task. Within the HIV+ group, current CD4+ count, though not nadir, was positively correlated with increased activity in the inferior frontal gyrus and basal ganglia. During phonemic fluency performance, HIV+ patients recruit subcortical structures to a greater degree than HIV- controls despite similar task performances suggesting that fMRI may be sensitive to neurocompromise before overt cognitive declines can be detected. Among HIV

Operational support to collision avoidance activities by ESA's space debris office

NASA Astrophysics Data System (ADS)

Braun, V.; Flohrer, T.; Krag, H.; Merz, K.; Lemmens, S.; Bastida Virgili, B.; Funke, Q.

2016-09-01

The European Space Agency's (ESA) Space Debris Office provides a service to support operational collision avoidance activities. This support currently covers ESA's missions Cryosat-2, Sentinel-1A and -2A, the constellation of Swarm-A/B/C in low-Earth orbit (LEO), as well as missions of third-party customers. In this work, we describe the current collision avoidance process for ESA and third-party missions in LEO. We give an overview on the upgrades developed and implemented since the advent of conjunction summary messages (CSM)/conjunction data messages (CDM), addressing conjunction event detection, collision risk assessment, orbit determination, orbit and covariance propagation, process control, and data handling. We pay special attention to the effect of warning thresholds on the risk reduction and manoeuvre rates, as they are established through risk mitigation and analysis tools, such as ESA's Debris Risk Assessment and Mitigation Analysis (DRAMA) software suite. To handle the large number of CDMs and the associated risk analyses, a database-centric approach has been developed. All CDMs and risk analysis results are stored in a database. In this way, a temporary local "mini-catalogue" of objects close to our target spacecraft is obtained, which can be used, e.g., for manoeuvre screening and to update the risk analysis whenever a new ephemeris becomes available from the flight dynamics team. The database is also used as the backbone for a Web-based tool, which consists of the visualization component and a collaboration tool that facilitates the status monitoring and task allocation within the support team as well as communication with the control team. The visualization component further supports the information sharing by displaying target and chaser motion over time along with the involved uncertainties. The Web-based solution optimally meets the needs for a concise and easy-to-use way to obtain a situation picture in a very short time, and the support for

Genetic variation in MAOA modulates prefrontal cortical regulation of approach-avoidance reactions.

PubMed

Ernst, Lena H; Lutz, Elisabeth; Ehlis, Ann-Christine; Fallgatter, Andreas J; Reif, Andreas; Plichta, Michael M

2013-01-01

Regulation of automatic approach and avoidance behavior requires affective and cognitive control, which are both influenced by a genetic variation in the gene encoding Monoamine Oxidase A (termed MAOA-uVNTR). The current study investigated MAOA genotype as a moderator of prefrontal cortical activation measured with functional near-infrared spectroscopy (fNIRS) in 37 healthy young adults during performance of the approach-avoidance task with positive and negative pictures. Carriers of the low- compared to the high-expressing genetic variant (MAOA-L vs. MAOA-H) showed increasing regulatory activity in the right dorsolateral prefrontal cortex (DLPFC) during incompatible conditions (approach negative, avoid positive). This might have been a compensatory mechanism for stronger emotional reactions as shown in previous studies and might have prevented any influence of incompatibility on behavior. In contrast, fewer errors but also lower activity in the right DLPFC during processing of negative compared to positive stimuli indicated MAOA-H carriers to have used other regulatory areas. This resulted in slower reaction times in incompatible conditions, but--in line with the known better cognitive regulation efficiency--allowed them to perform incompatible reactions without activating the DLPFC as the highest control instance. Carriers of one low- and one high-expressing allele lay as an intermediate group between the reactions of the low- and high-expressing groups. The relatively small sample size and restriction to fNIRS for assessment of cortical activity limit our findings. Nevertheless, these first results suggest monoam-inergic mechanisms to contribute to interindividual differences in the two basic behavioral principles of approach and avoidance and their neuronal correlates. Copyright © 2013 S. Karger AG, Basel.

Task Lists for Health Occupations. Radiologic Aide. Activity Aide. Optometric Assistant. Physical Therapy Aide. Education for Employment Task Lists.

ERIC Educational Resources Information Center

Lathrop, Janice

These task lists contain employability skills and tasks for the following health occupations: radiologic aide, activity aide, physical therapy aide, and optometric assistant. The duties and tasks found in these lists form the basis of instructional content for secondary, postsecondary, and adult occupational training programs. Employability skills…

Lesions of the lateral habenula facilitate active avoidance learning and threat extinction.

PubMed

Song, Mihee; Jo, Yong Sang; Lee, Yeon-Kyung; Choi, June-Seek

2017-02-01

The lateral habenula (LHb) is an epithalamic brain structure that provides strong projections to midbrain monoaminergic systems that are involved in motivation, emotion, and reinforcement learning. LHb neurons are known to convey information about aversive outcomes and negative prediction errors, suggesting a role in learning from aversive events. To test this idea, we examined the effects of electrolytic lesions of the LHb on signaled two-way active avoidance learning in which rats were trained to avoid an unconditioned stimulus (US) by taking a proactive shuttling response to an auditory conditioned stimulus (CS). The lesioned animals learned the avoidance response significantly faster than the control groups. In a separate experiment, we also investigated whether the LHb contributes to Pavlovian threat (fear) conditioning and extinction. Following paired presentations of the CS and the US, LHb-lesioned animals showed normal acquisition of conditioned response (CR) measured with freezing. However, extinction of the CR in the subsequent CS-only session was significantly faster. The enhanced performance in avoidance learning and in threat extinction jointly suggests that the LHb normally plays an inhibitory role in learning driven by absence of aversive outcomes. Copyright © 2016 Elsevier B.V. All rights reserved.

Reward Activates Stimulus-Specific and Task-Dependent Representations in Visual Association Cortices

PubMed Central

Muller, Timothy; Yeung, Nick; Waszak, Florian

2014-01-01

Humans reliably learn which actions lead to rewards. One prominent question is how credit is assigned to environmental stimuli that are acted upon. Recent functional magnetic resonance imaging (fMRI) studies have provided evidence that representations of rewarded stimuli are activated upon reward delivery, providing possible eligibility traces for credit assignment. Our study sought evidence of postreward activation in sensory cortices satisfying two conditions of instrumental learning: postreward activity should reflect the stimulus category that preceded reward (stimulus specificity), and should occur only if the stimulus was acted on to obtain reward (task dependency). Our experiment implemented two tasks in the fMRI scanner. The first was a perceptual decision-making task on degraded face and house stimuli. Stimulus specificity was evident as rewards activated the sensory cortices associated with face versus house perception more strongly after face versus house decisions, respectively, particularly in the fusiform face area. Stimulus specificity was further evident in a psychophysiological interaction analysis wherein face-sensitive areas correlated with nucleus accumbens activity after face-decision rewards, whereas house-sensitive areas correlated with nucleus accumbens activity after house-decision rewards. The second task required participants to make an instructed response. The criterion of task dependency was fulfilled as rewards after face versus house responses activated the respective association cortices to a larger degree when faces and houses were relevant to the performed task. Our study is the first to show that postreward sensory cortex activity meets these two key criteria of credit assignment, and does so independently from bottom-up perceptual processing. PMID:25411489

An Avoidance-Based Rodent Model of Exposure With Response Prevention Therapy for Obsessive-Compulsive Disorder.

PubMed

Rodriguez-Romaguera, Jose; Greenberg, Benjamin D; Rasmussen, Steven A; Quirk, Gregory J

2016-10-01

Obsessive-compulsive disorder is treated with exposure with response prevention (ERP) therapy, in which patients are repeatedly exposed to compulsive triggers but prevented from expressing their compulsions. Many compulsions are an attempt to avoid perceived dangers, and the intent of ERP is to extinguish compulsions. Patients failing ERP therapy are candidates for deep brain stimulation (DBS) of the ventral capsule/ventral striatum, which facilitates patients' response to ERP therapy. An animal model of ERP would be useful for understanding the neural mechanisms of extinction in obsessive-compulsive disorder. Using a platform-mediated signaled avoidance task, we developed a rodent model of ERP called extinction with response prevention (Ext-RP), in which avoidance-conditioned rats are given extinction trials while blocking access to the avoidance platform. Following 3 days of Ext-RP, rats were tested with the platform unblocked to evaluate persistent avoidance. We then assessed if pharmacologic inactivation of lateral orbitofrontal cortex (lOFC) or DBS of the ventral striatum reduced persistent avoidance. Following Ext-RP training, most rats showed reduced avoidance at test (Ext-RP success), but a subset persisted in their avoidance (Ext-RP failure). Pharmacologic inactivation of lOFC eliminated persistent avoidance, as did DBS applied to the ventral striatum during Ext-RP. DBS of ventral striatum has been previously shown to inhibit lOFC activity. Thus, activity in lOFC, which is known to be hyperactive in obsessive-compulsive disorder, may be responsible for impairing patients' response to ERP therapy. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Upper Limb Muscle and Brain Activity in Light Assembly Task on Different Load Levels

NASA Astrophysics Data System (ADS)

Zadry, Hilma Raimona; Dawal, Siti Zawiah Md.; Taha, Zahari

2010-10-01

A study was conducted to investigate the effect of load on upper limb muscles and brain activities in light assembly task. The task was conducted at two levels of load (Low and high). Surface electromyography (EMG) was used to measure upper limb muscle activities of twenty subjects. Electroencephalography (EEG) was simultaneously recorded with EMG to record brain activities from Fz, Pz, O1 and O2 channels. The EMG Mean Power Frequency (MPF) of the right brachioradialis and the left upper trapezius activities were higher on the high-load task compared to low-load task. The EMG MPF values also decrease as time increases, that reflects muscle fatigue. Mean power of the EEG alpha bands for the Fz-Pz channels were found to be higher on the high-load task compared to low-load task, while for the O1-O2 channels, they were higher on the low-load task than on the high-load task. These results indicated that the load levels effect the upper limb muscle and brain activities. The high-load task will increase muscle activities on the right brachioradialis and the left upper tapezius muscles, and will increase the awareness and motivation of the subjects. Whilst the low-load task can generate drowsiness earlier. It signified that the longer the time and the more heavy of the task, the subjects will be more fatigue physically and mentally.

Left inferior-parietal lobe activity in perspective tasks: identity statements

PubMed Central

Arora, Aditi; Weiss, Benjamin; Schurz, Matthias; Aichhorn, Markus; Wieshofer, Rebecca C.; Perner, Josef

2015-01-01

We investigate the theory that the left inferior parietal lobe (IPL) is closely associated with tracking potential differences of perspective. Developmental studies find that perspective tasks are mastered at around 4 years of age. Our first study, meta-analyses of brain imaging studies shows that perspective tasks specifically activate a region in the left IPL and precuneus. These tasks include processing of false belief, visual perspective, and episodic memory. We test the location specificity theory in our second study with an unusual and novel kind of perspective task: identity statements. According to Frege's classical logical analysis, identity statements require appreciation of modes of presentation (perspectives). We show that identity statements, e.g., “the tour guide is also the driver” activate the left IPL in contrast to a control statements, “the tour guide has an apprentice.” This activation overlaps with the activations found in the meta-analysis. This finding is confirmed in a third study with different types of statements and different comparisons. All studies support the theory that the left IPL has as one of its overarching functions the tracking of perspective differences. We discuss how this function relates to the bottom-up attention function proposed for the bilateral IPL. PMID:26175677

Advantages and disadvantages of intraoperative language tasks in awake surgery: a three-task approach for prefrontal tumors.

PubMed

Rofes, A; Spena, G; Miozzo, A; Fontanella, M M; Miceli, G

2015-12-01

Multidisciplinary efforts are being made to provide surgical teams with sensitive and specific tasks for language mapping in awake surgery. Researchers and clinicians have elaborated different tasks over time. A fair amount of work has been directed to study the neurofunctional correlates of some of these tasks, and there is recent interest in their standardization. However, little discussion exists on the advantages and disadvantages that each task poses from the perspective of the cognitive neuroscience of language. Such an approach may be a relevant step to assess task validity, to avoid using tasks that tap onto similar processes, and to provide patients with a surgical treatment that ensures maximal tumor resection while avoiding postoperative language deficits. An understanding of the language components that each task entails may also be relevant to improve the current assessments and the ways in which tasks are administered, and to disentangle neurofunctional questions. We reviewed 17 language mapping tasks that have been used in awake surgery. Overt production tasks have been a preferred choice over comprehension tasks. Tasks tapping lexico-semantic processes, particularly object-naming, maintain their role as gold standards. Automated speech tasks are used to detect speech errors and to set the amplitude of the stimulator. Comprehension tasks, reading and writing tasks, and tasks that assess grammatical aspects of language may be regularly administered in the near future. We provide examples of a three-task approach we are administering to patients with prefrontal lesions. We believe that future advances in this area are contingent upon reviewing gold standards and introducing new assessment tools.

ICA model order selection of task co-activation networks.

PubMed

Ray, Kimberly L; McKay, D Reese; Fox, Peter M; Riedel, Michael C; Uecker, Angela M; Beckmann, Christian F; Smith, Stephen M; Fox, Peter T; Laird, Angela R

2013-01-01

Independent component analysis (ICA) has become a widely used method for extracting functional networks in the brain during rest and task. Historically, preferred ICA dimensionality has widely varied within the neuroimaging community, but typically varies between 20 and 100 components. This can be problematic when comparing results across multiple studies because of the impact ICA dimensionality has on the topology of its resultant components. Recent studies have demonstrated that ICA can be applied to peak activation coordinates archived in a large neuroimaging database (i.e., BrainMap Database) to yield whole-brain task-based co-activation networks. A strength of applying ICA to BrainMap data is that the vast amount of metadata in BrainMap can be used to quantitatively assess tasks and cognitive processes contributing to each component. In this study, we investigated the effect of model order on the distribution of functional properties across networks as a method for identifying the most informative decompositions of BrainMap-based ICA components. Our findings suggest dimensionality of 20 for low model order ICA to examine large-scale brain networks, and dimensionality of 70 to provide insight into how large-scale networks fractionate into sub-networks. We also provide a functional and organizational assessment of visual, motor, emotion, and interoceptive task co-activation networks as they fractionate from low to high model-orders.

ICA model order selection of task co-activation networks

PubMed Central

Ray, Kimberly L.; McKay, D. Reese; Fox, Peter M.; Riedel, Michael C.; Uecker, Angela M.; Beckmann, Christian F.; Smith, Stephen M.; Fox, Peter T.; Laird, Angela R.

2013-01-01

Independent component analysis (ICA) has become a widely used method for extracting functional networks in the brain during rest and task. Historically, preferred ICA dimensionality has widely varied within the neuroimaging community, but typically varies between 20 and 100 components. This can be problematic when comparing results across multiple studies because of the impact ICA dimensionality has on the topology of its resultant components. Recent studies have demonstrated that ICA can be applied to peak activation coordinates archived in a large neuroimaging database (i.e., BrainMap Database) to yield whole-brain task-based co-activation networks. A strength of applying ICA to BrainMap data is that the vast amount of metadata in BrainMap can be used to quantitatively assess tasks and cognitive processes contributing to each component. In this study, we investigated the effect of model order on the distribution of functional properties across networks as a method for identifying the most informative decompositions of BrainMap-based ICA components. Our findings suggest dimensionality of 20 for low model order ICA to examine large-scale brain networks, and dimensionality of 70 to provide insight into how large-scale networks fractionate into sub-networks. We also provide a functional and organizational assessment of visual, motor, emotion, and interoceptive task co-activation networks as they fractionate from low to high model-orders. PMID:24339802

Aversive disinhibition of behavior and striatal signaling in social avoidance.

PubMed

Ly, Verena; Cools, Roshan; Roelofs, Karin

2014-10-01

Social avoidance is a major factor contributing to the development and maintenance of anxiety and depressive symptoms. Converging evidence suggests that social avoidance is associated with abnormal aversive processing and hyperactive amygdala signaling. However, what are the consequences of such abnormal aversive processing for action and for the neural mechanisms implementing action is unclear. Existing literature is conflicting, pointing at either enhanced or reduced action inhibition. We investigated the interaction between aversion and action in social avoidance by comparing the effects of aversive vs appetitive faces on a go/no-go task and associated striatal signals in 42 high and low socially avoidant individuals. We combined fMRI with a novel probabilistic learning task, in which emotional valence (angry and happy faces) and optimal response (go- and no-go-responses) were manipulated independently. High compared with low socially avoidant individuals showed reduced behavioral inhibition (proportion no-go-responses) for angry relative to happy faces. This behavioral disinhibition correlated with greater striatal signal during no-go-responses for angry relative to happy faces. The results suggest that social avoidant coping style is accompanied by disinhibition of action and striatal signal in the context of social threat. The findings concur with recent theorizing about aversive disinhibition and affective disorders. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Tools for Activating Materials and Tasks in the English Language Classroom

ERIC Educational Resources Information Center

Rosenberg, Rick

2009-01-01

Most teachers have seen the reactions students can have to tasks and activities that they do not find engaging: the glassy or rolling eyes, the unfocused behavior, and the cries of "Not again!" This article provides practical techniques that the author's students have helped him learn over the years to better "activate" materials and tasks in the…

Risk avoidance versus risk reduction: a framework and segmentation profile for understanding adolescent sexual activity.

PubMed

Hopkins, Christopher D; Tanner, John F; Raymond, Mary Anne

2004-01-01

The teen birthrate in the United States is twice that of other industrialized nations. Adolescents in the U.S. are among high-risk groups for HIV/AIDS and other sexually transmitted diseases. As a result, the Department of Health and Human Services changed its policy on the promotion of abstinence to teenagers from a focus on a risk reduction strategy to a focus on a risk avoidance strategy. In order to create more effective risk avoidance as well as risk reduction campaigns, this study proposes a framework to illustrate the distinction that teens make between spontaneous sexual activity and planned sexual activity, as well as those teens that make a commitment to abstinence versus abstinence by default. Furthermore, this study classifies teens into three behavior segments (abstemious, promiscuous and monogamous) and then assesses specific differences that exist within these groups relative to their attitudes and perceptions concerning abstinence, sexual activity, contraception, fear and norms. This change in focus from a risk reduction to a risk avoidance strategy has important implications for social marketing, public policy and marketing theory.

Vigilance-avoidance and disengagement are differentially associated with fear and avoidant behaviors in social anxiety.

PubMed

Evans, Travis C; Walukevich, Katherine A; Britton, Jennifer C

2016-07-15

Individuals with Social Anxiety Disorder (SAD) often exhibit preferential attention for social threat, demonstrating abnormal orientation to threat (i.e., vigilance-avoidance) and/or difficulty disengaging from threat. However, no research has compared the relationship between attention indices (i.e., vigilance-avoidance, difficulty disengaging from threat) and characteristic features of the disorder such as fear during social situations (social fear) and avoidant behaviors (social avoidance). To address this issue, seventy adults (19.29±1.47 years, 33 females) were separated into low (n=37) or high (n=33) socially anxious groups using clinical cutoff scores on the Social Interaction Anxiety Scale (SIAS). Participants in both groups completed a dot-probe task with congruent, incongruent, and neutral trials to obtain measures of vigilance-avoidance and difficulty disengaging. Using linear regression, we examined the associations each attention index shared with self-reported social fear and social avoidance. Exclusively in the high anxious group, greater vigilance towards threat was associated with higher self-reported social fear, but not with social avoidance. However, difficulty disengaging was not associated with either social measure. In the low anxiety group, no relationships between attention indices and either social measure emerged. Future research with clinical samples is necessary to replicate and extend these findings. The small sample size studied may have limited our ability to detect other smaller effects. Indices of attention bias may contribute differently to the etiology and maintenance of SAD, which offers important implications for novel treatments that target attention. Copyright © 2016 Elsevier B.V. All rights reserved.

Patterns of brain and cardiovascular activation while solving rule-discovery and rule-application numeric tasks.

PubMed

Sosnowski, Tytus; Rynkiewicz, Andrzej; Wordecha, Małgorzata; Kępkowicz, Anna; Majewska, Adrianna; Pstrągowska, Aleksandra; Oleksy, Tomasz; Wypych, Marek; Marchewka, Artur

2017-07-01

It is known that solving mental tasks leads to tonic increase in cardiovascular activity. Our previous research showed that tasks involving rule application (RA) caused greater tonic increase in cardiovascular activity than tasks requiring rule discovery (RD). However, it is not clear what brain mechanisms are responsible for this difference. The aim of two experimental studies was to compare the patterns of brain and cardiovascular activity while both RD and the RA numeric tasks were being solved. The fMRI study revealed greater brain activation while solving RD tasks than while solving RA tasks. In particular, RD tasks evoked greater activation of the left inferior frontal gyrus and selected areas in the parietal, and temporal cortices, including the precuneus, supramarginal gyrus, angular gyrus, inferior parietal lobule, and the superior temporal gyrus, and the cingulate cortex. In addition, RA tasks caused larger increases in HR than RD tasks. The second study, carried out in a cardiovascular laboratory, showed greater increases in heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) while solving RA tasks than while solving RD tasks. The results support the hypothesis that RD and RA tasks involve different modes of information processing, but the neuronal mechanism responsible for the observed greater cardiovascular response to RA tasks than to RD tasks is not completely clear. Copyright © 2017. Published by Elsevier B.V.

Linguistic Characteristics of ESL Writing in Task-based E-mail Activities.

ERIC Educational Resources Information Center

Li, Yili

2000-01-01

Investigated the efficacy of integrating task-based e-mail activities into a process-oriented English-as-Second-Language (ESL) writing class. Particular focus was on the linguistic characteristics of 132 pieces of e-mail writing by ESL students in tasks that differed in terms of purpose, audience interaction, and task structure. Computerized text…

Public speaking avoidance as a treatment moderator for social anxiety disorder.

PubMed

Mesri, Bita; Niles, Andrea N; Pittig, Andre; LeBeau, Richard T; Haik, Ethan; Craske, Michelle G

2017-06-01

Cognitive behavioral therapy (CBT) and acceptance and commitment therapy (ACT) have both garnered empirical support for the effective treatment of social anxiety disorder. However, not every patient benefits equally from either treatment. Identifying moderators of treatment outcome can help to better understand which treatment is best suited for a particular patient. Forty-nine individuals who met criteria for social anxiety disorder were assessed as part of a randomized controlled trial comparing 12 weeks of CBT and ACT. Pre-treatment avoidance of social situations (measured via a public speaking task and clinician rating) was investigated as a moderator of post-treatment, 6-month follow-up, and 12-month follow-up social anxiety symptoms, stress reactivity, and quality of life. Public speaking avoidance was found to be a robust moderator of outcome measures, with more avoidant individuals generally benefitting more from CBT than ACT by 12-month follow-up. In contrast, clinician-rated social avoidance was not found to be a significant moderator of any outcome measure. Results were found only at 12-month follow-up. More comprehensive measures of avoidance would be useful for the field moving forward. Findings inform personalized medicine, suggesting that social avoidance measured behaviorally via a public speaking task may be a more robust factor in treatment prescription compared to clinician-rated social avoidance. Published by Elsevier Ltd.

Optimal consensus algorithm integrated with obstacle avoidance

NASA Astrophysics Data System (ADS)

Wang, Jianan; Xin, Ming

2013-01-01

This article proposes a new consensus algorithm for the networked single-integrator systems in an obstacle-laden environment. A novel optimal control approach is utilised to achieve not only multi-agent consensus but also obstacle avoidance capability with minimised control efforts. Three cost functional components are defined to fulfil the respective tasks. In particular, an innovative nonquadratic obstacle avoidance cost function is constructed from an inverse optimal control perspective. The other two components are designed to ensure consensus and constrain the control effort. The asymptotic stability and optimality are proven. In addition, the distributed and analytical optimal control law only requires local information based on the communication topology to guarantee the proposed behaviours, rather than all agents' information. The consensus and obstacle avoidance are validated through simulations.

Return to activity after concussion affects dual-task gait balance control recovery.

PubMed

Howell, David R; Osternig, Louis R; Chou, Li-Shan

2015-04-01

Recent work has identified deficits in dual-task gait balance control for up to 2 months after adolescent concussion; however, how resumption of preinjury physical activities affects recovery is unknown. The objective of this study is to examine how return to activity (RTA) affects recovery from concussion on measures of symptom severity, cognition, and balance control during single-task and dual-task walking. Nineteen adolescents with concussion who returned to preinjury activity within 2 months after injury and 19 uninjured, matched controls completed symptom inventories, computerized cognitive testing, and single-task and dual-task gait analyses. Concussion participants were assessed at five time points: within 72 h, 1 wk, 2 wk, 1 month, and 2 months postinjury. Control participants were assessed at the same time points as their matched concussion counterparts. RTA day was documented as the postinjury day in which physical activity participation was allowed. The effect of returning to physical activity was assessed by examining the percent change on each dependent variable across time before and directly after the RTA. Data were analyzed by two-way mixed effects ANOVAs. After the RTA day, concussion participants significantly increased their total center-of-mass medial/lateral displacement (P = 0.009, ηp = .175) and peak velocity (P = 0.048, ηp = 0.104) during dual-task walking when compared with pre-RTA data, whereas no changes for the concussion group or between groups were detected on measures of single-task walking, forward movement, or cognition. Adolescents with concussion displayed increased center-of-mass medial/lateral displacement and velocity during dual-task walking after RTA, suggesting a regression of recovery in gait balance control. This study reinforces the need for a multifaceted approach to concussion management and continued monitoring beyond the point of clinical recovery.

Upper Extremity Muscle Activity During In-Phase and Anti-Phase Continuous Pushing Tasks.

PubMed

Gruevski, Kristina M; Hodder, Joanne N; Keir, Peter J

2017-11-01

To determine the effect of anti-phase, in-phase bimanual and unimanual simulated industrial pushing tasks and frequency on upper extremity muscle activity. Research investigating symmetrical (in-phase) and asymmetrical (anti-phase) pushing exertions is limited despite a high prevalence in industry. Fifteen female participants completed five pushing tasks using a dual handle apparatus at three frequencies: 15 cycles per minute (cpm), 30 cpm, and self-selected. Tasks included two bimanual symmetrical pushes (constrained and unconstrained), two bimanual asymmetrical pushes (reciprocating and continuous), and one right unimanual push. Surface electromyography (EMG) from the right anterior, middle, and posterior deltoid (AD, MD, and PD); right and left trapezius (RT and LT); right pectoralis major (PM); and right and left external obliques (REO and LEO) was collected and normalized to maximum voluntary effort. There was a task by frequency interaction in the AD, MD, PD, and RT ( p < .005), where activity in AD, MD, and PD was highest in the continuous task at 15 cpm, but activity was similar across task in 30 cpm and self-selected. Muscle activity coefficient of variation was lowest during continuous task across all frequencies. Continuous, anti-phase pushes and constrained, in-phase pushes had the highest muscle activity demands and the least amount of variability in muscle activity and therefore may present the greatest risk of injury. Anti-phase pushing is known to have a greater cognitive demand, and this study demonstrated that it also has a greater physical demand when performed continuously.

Requirement of NF-kappa B Activation in Different Mice Brain Areas during Long-Term Memory Consolidation in Two Contextual One-Trial Tasks with Opposing Valences

PubMed Central

Salles, Angeles; Krawczyk, Maria del C.; Blake, Mariano; Romano, Arturo; Boccia, Mariano M.; Freudenthal, Ramiro

2017-01-01

NF-kappa B is a transcription factor whose activation has been shown to be necessary for long-term memory consolidation in several species. NF-kappa B is activated and translocates to the nucleus of cells in a specific temporal window during consolidation. Our work focuses on a one trial learning tasks associated to the inhibitory avoidance (IA) setting. Mice were trained either receiving or not a footshock when entering a dark compartment (aversive vs. appetitive learning). Regardless of training condition (appetitive or aversive), latencies to step-through during testing were significantly different to those measured during training. Additionally, these testing latencies were also different from those of a control group that only received a shock unrelated to context. Moreover, nuclear NF-kappa B DNA-binding activity was augmented in the aversive and the appetitive tasks when compared with control and naïve animals. NF-kappa B inhibition by Sulfasalazine injected either in the Hippocampus, Amygdala or Nucleus accumbens immediately after training was able to impair retention in both training versions. Our results suggest that NF-kappa B is a critical molecular step, in different brain areas on memory consolidation. This was the case for both the IA task and also the modified version of the same task where the footshock was omitted during training. This work aims to further investigate how appetitive and aversive memories are consolidated. PMID:28439227

NCAM deficiency in the mouse forebrain impairs innate and learned avoidance behaviours.

PubMed

Brandewiede, J; Stork, O; Schachner, M

2014-06-01

The neural cell adhesion molecule (NCAM) has been implicated in the development and plasticity of neural circuits and the control of hippocampus- and amygdala-dependent learning and behaviour. Previous studies in constitutive NCAM null mutants identified emotional behaviour deficits related to disturbances of hippocampal and amygdala functions. Here, we studied these behaviours in mice conditionally deficient in NCAM in the postmigratory forebrain neurons. We report deficits in both innate and learned avoidance behaviours, as observed in elevated plus maze and passive avoidance tasks. In contrast, general locomotor activity, trait anxiety or neophobia were unaffected by the mutation. Altered avoidance behaviour of the conditional NCAM mutants was associated with a deficit in serotonergic signalling, as indicated by their reduced responsiveness to (±)-8-hydroxy-2-(dipropylamino)-tetralin-induced hypothermia. Another serotonin-dependent behaviour, namely intermale aggression that is massively increased in constitutively NCAM-deficient mice, was not affected in the forebrain-specific mutants. Our data suggest that genetically or environmentally induced changes of NCAM expression in the late postnatal and mature forebrain determine avoidance behaviour and serotonin (5-HT)1A receptor signalling. © 2014 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Asymptotically Optimal Motion Planning for Learned Tasks Using Time-Dependent Cost Maps

PubMed Central

Bowen, Chris; Ye, Gu; Alterovitz, Ron

2015-01-01

In unstructured environments in people’s homes and workspaces, robots executing a task may need to avoid obstacles while satisfying task motion constraints, e.g., keeping a plate of food level to avoid spills or properly orienting a finger to push a button. We introduce a sampling-based method for computing motion plans that are collision-free and minimize a cost metric that encodes task motion constraints. Our time-dependent cost metric, learned from a set of demonstrations, encodes features of a task’s motion that are consistent across the demonstrations and, hence, are likely required to successfully execute the task. Our sampling-based motion planner uses the learned cost metric to compute plans that simultaneously avoid obstacles and satisfy task constraints. The motion planner is asymptotically optimal and minimizes the Mahalanobis distance between the planned trajectory and the distribution of demonstrations in a feature space parameterized by the locations of task-relevant objects. The motion planner also leverages the distribution of the demonstrations to significantly reduce plan computation time. We demonstrate the method’s effectiveness and speed using a small humanoid robot performing tasks requiring both obstacle avoidance and satisfaction of learned task constraints. Note to Practitioners Motivated by the desire to enable robots to autonomously operate in cluttered home and workplace environments, this paper presents an approach for intuitively training a robot in a manner that enables it to repeat the task in novel scenarios and in the presence of unforeseen obstacles in the environment. Based on user-provided demonstrations of the task, our method learns features of the task that are consistent across the demonstrations and that we expect should be repeated by the robot when performing the task. We next present an efficient algorithm for planning robot motions to perform the task based on the learned features while avoiding obstacles. We

Grid Task Execution

NASA Technical Reports Server (NTRS)

Hu, Chaumin

2007-01-01

IPG Execution Service is a framework that reliably executes complex jobs on a computational grid, and is part of the IPG service architecture designed to support location-independent computing. The new grid service enables users to describe the platform on which they need a job to run, which allows the service to locate the desired platform, configure it for the required application, and execute the job. After a job is submitted, users can monitor it through periodic notifications, or through queries. Each job consists of a set of tasks that performs actions such as executing applications and managing data. Each task is executed based on a starting condition that is an expression of the states of other tasks. This formulation allows tasks to be executed in parallel, and also allows a user to specify tasks to execute when other tasks succeed, fail, or are canceled. The two core components of the Execution Service are the Task Database, which stores tasks that have been submitted for execution, and the Task Manager, which executes tasks in the proper order, based on the user-specified starting conditions, and avoids overloading local and remote resources while executing tasks.

Violence Exposure and Psychopathology in Latino Youth: The Moderating Role of Active and Avoidant Coping.

PubMed

Gudiño, Omar G; Stiles, Allison A; Diaz, Kathleen I

2018-06-01

Despite high rates of exposure to community violence among Latino youth in urban communities, there is considerable variability in individual outcomes. This study examined (a) associations between coping and indices of Latino culture, (b) main effects of active/avoidant coping on psychopathology, and (c) whether coping moderates the impact of violence exposure on mental health in Latino youth. Participants included 168 Latino youth (56% female; ages 11-14) that took part in a short-term longitudinal study. Results indicate that youth acculturation was positively associated with active coping, but enculturation level and immigrant status were not associated with coping. Structural equation models suggested that active coping was negatively associated with internalizing problems (p = .046) while avoidant coping was positively associated with internalizing problems (p = .013) and posttraumatic stress symptoms (p = .024). Moderation analyses revealed that violence exposure was more strongly associated with internalizing problems as reliance on avoidance coping increased. However, at high levels of violence exposure, a greater reliance on active coping was related to increased posttraumatic stress problems. Findings suggest that consideration of the specific stressor, level of stress exposure, and mental health problem-type may be crucial in determining the effectiveness of a coping strategy. Implications for future research and intervention are discussed.

Development and Initial Validation of the Activity Patterns Scale in Patients With Chronic Pain.

PubMed

Esteve, Rosa; Ramírez-Maestre, Carmen; Peters, Madelon L; Serrano-Ibáñez, Elena R; Ruíz-Párraga, Gema T; López-Martínez, Alicia E

2016-04-01

Several self-report measures were used to identify 6 activity patterns in chronic pain patients: pain avoidance, activity avoidance, task-contingent persistence, excessive persistence, pain-contingent persistence, and pacing. Instruments for assessing pacing should include 3 pacing behaviors (breaking tasks into smaller tasks, taking frequent short rests, slowing down), each of which relate to a single goal (increasing activity levels, conserving energy for valued activities, and reducing pain). This article presents the Activity Patterns Scale (APS), which assesses these 6 activity patterns. Study 1 included 291 participants with chronic pain, and tested 3 structures using confirmatory factor analyses. The structure with the best fit had 8 factors corresponding to the hypothesized scales. High correlations in the expected direction were found between the APS subscales and the "Patterns of Activity Measure-Pain." Study 2 included 111 patients with chronic pain, and aimed at examining the association between the APS subscales and adjustment to pain. It was found that that activity avoidance was associated with daily functioning and impairment. Negative affect was positively associated with activity avoidance and excessive persistence, and negatively associated with task-contingent persistence, which was also positively associated with positive affect. This study showed that the APS is a valid and reliable instrument for clinical practice and research. This article presents a valid and reliable instrument to assess activity patterns in patients with chronic pain. The findings suggest that avoidance, persistence, and pacing are multidimensional constructs. Distinguishing between these dimensions sheds light on previous contradictory results and has direct clinical implications regarding recommending the most advisable activity patterns. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.

α1-Adrenoceptors in the hippocampal dentate gyrus involved in learning-dependent long-term potentiation during active-avoidance learning in rats.

PubMed

Lv, Jing; Zhan, Su-Yang; Li, Guang-Xie; Wang, Dan; Li, Ying-Shun; Jin, Qing-Hua

2016-11-09

The hippocampus is the key structure for learning and memory in mammals and long-term potentiation (LTP) is an important cellular mechanism responsible for learning and memory. The influences of norepinephrine (NE) on the modulation of learning and memory, as well as LTP, through β-adrenoceptors are well documented, whereas the role of α1-adrenoceptors in learning-dependent LTP is not yet clear. In the present study, we measured extracellular concentrations of NE in the hippocampal dentate gyrus (DG) region using an in-vivo brain microdialysis and high-performance liquid chromatography techniques during the acquisition and extinction of active-avoidance behavior in freely moving conscious rats. Next, the effects of prazosin (an antagonist of α1-adrenoceptor) and phenylephrine (an agonist of the α1-adrenoceptor) on amplitudes of field excitatory postsynaptic potential were measured in the DG region during the active-avoidance behavior. Our results showed that the extracellular concentration of NE in the DG was significantly increased during the acquisition of active-avoidance behavior and gradually returned to the baseline level following extinction training. A local microinjection of prazosin into the DG significantly accelerated the acquisition of the active-avoidance behavior, whereas a local microinjection of phenylephrine retarded the acquisition of the active-avoidance behavior. Furthermore, in all groups, the changes in field excitatory postsynaptic potential amplitude were accompanied by corresponding changes in active-avoidance behavior. Our results suggest that NE activation of α1-adrenoceptors in the hippocampal DG inhibits active-avoidance learning by modulation of synaptic efficiency in rats.

Formal Derivation of Lotka-Volterra-Haken Amplitude Equations of Task-Related Brain Activity in Multiple, Consecutively Performed Tasks

NASA Astrophysics Data System (ADS)

Frank, T. D.

The Lotka-Volterra-Haken equations have been frequently used in ecology and pattern formation. Recently, the equations have been proposed by several research groups as amplitude equations for task-related patterns of brain activity. In this theoretical study, the focus is on the circular causality aspect of pattern formation systems as formulated within the framework of synergetics. Accordingly, the stable modes of a pattern formation system inhibit the unstable modes, whereas the unstable modes excite the stable modes. Using this circular causality principle it is shown that under certain conditions the Lotka-Volterra-Haken amplitude equations can be derived from a general model of brain activity akin to the Wilson-Cowan model. The model captures the amplitude dynamics for brain activity patterns in experiments involving several consecutively performed multiple-choice tasks. This is explicitly demonstrated for two-choice tasks involving grasping and walking. A comment on the relevance of the theoretical framework for clinical psychology and schizophrenia is given as well.

Avoidance of seismic survey activities by penguins.

PubMed

Pichegru, Lorien; Nyengera, Reason; McInnes, Alistair M; Pistorius, Pierre

2017-11-24

Seismic surveys in search for oil or gas under the seabed, produce the most intense man-made ocean noise with known impacts on invertebrates, fish and marine mammals. No evidence to date exists, however, about potential impacts on seabirds. Penguins may be expected to be particularly affected by loud underwater sounds, due to their largely aquatic existence. This study investigated the behavioural response of breeding endangered African Penguins Spheniscus demersus to seismic surveys within 100 km of their colony in South Africa, using a multi-year GPS tracking dataset. Penguins showed a strong avoidance of their preferred foraging areas during seismic activities, foraging significantly further from the survey vessel when in operation, while increasing their overall foraging effort. The birds reverted to normal behaviour when the operation ceased, although longer-term repercussions on hearing capacities cannot be precluded. The rapid industrialization of the oceans has increased levels of underwater anthropogenic noises globally, a growing concern for a wide range of taxa, now also including seabirds. African penguin numbers have decreased by 70% in the last 10 years, a strong motivation for precautionary management decisions, including the exclusion of seismic exploratory activities within at least 100 km of their breeding colonies.

Children's Avoidance of Interrupting Others' Activities in Requesting Help: Cultural Aspects of Considerateness.

PubMed

Ruvalcaba, Omar; Rogoff, Barbara; López, Angélica; Correa-Chávez, Maricela; Gutiérrez, Kris

2015-01-01

To be able to collaborate skillfully, people need to coordinate well with others, taking into account how their actions fit with those of their partners. This is a key aspect of an approach to learning called Learning by Observing and Pitching In, hypothesized to be common in many Indigenous-heritage communities of the Americas. This chapter considers cultural values that emphasize considerateness and awareness of how one's actions impact others such as the Mexican cultural value of respeto and cultural differences in children's efforts to avoid interrupting others' activity. US Mexican-heritage children showed more evidence of avoiding interrupting the ongoing activity of an adult when they requested help, compared with European American children from families with extensive schooling experience. Most of the Mexican-heritage children's requests for help that gave evidence of avoiding interruption were made nonverbally, which may facilitate unobtrusive requests. There were no significant differences among children from two US Mexican-heritage backgrounds varying in experience with Western schooling and likely experience with Indigenous-American practices, suggesting that the Mexican cultural value of respeto and associated considerateness is widespread even among US Mexican-heritage families with extensive experience with Western schooling and life in the United States. © 2015 Elsevier Inc. All rights reserved.

Avoidant decision making in social anxiety: the interaction of angry faces and emotional responses

PubMed Central

Pittig, Andre; Pawlikowski, Mirko; Craske, Michelle G.; Alpers, Georg W.

2014-01-01

Recent research indicates that angry facial expressions are preferentially processed and may facilitate automatic avoidance response, especially in socially anxious individuals. However, few studies have examined whether this bias also expresses itself in more complex cognitive processes and behavior such as decision making. We recently introduced a variation of the Iowa Gambling Task which allowed us to document the influence of task-irrelevant emotional cues on rational decision making. The present study used a modified gambling task to investigate the impact of angry facial expressions on decision making in 38 individuals with a wide range of social anxiety. Participants were to find out which choices were (dis-) advantageous to maximize overall gain. To create a decision conflict between approach of reward and avoidance of fear-relevant angry faces, advantageous choices were associated with angry facial expressions, whereas disadvantageous choices were associated with happy facial expressions. Results indicated that higher social avoidance predicted less advantageous decisions in the beginning of the task, i.e., when contingencies were still uncertain. Interactions with specific skin conductance responses further clarified that this initial avoidance only occurred in combination with elevated responses before choosing an angry facial expressions. In addition, an interaction between high trait anxiety and elevated responses to early losses predicted faster learning of an advantageous strategy. These effects were independent of intelligence, general risky decision-making, self-reported state anxiety, and depression. Thus, socially avoidant individuals who respond emotionally to angry facial expressions are more likely to show avoidance of these faces under uncertainty. This novel laboratory paradigm may be an appropriate analog for central features of social anxiety. PMID:25324792

Avoidant decision making in social anxiety: the interaction of angry faces and emotional responses.

PubMed

Pittig, Andre; Pawlikowski, Mirko; Craske, Michelle G; Alpers, Georg W

2014-01-01

Recent research indicates that angry facial expressions are preferentially processed and may facilitate automatic avoidance response, especially in socially anxious individuals. However, few studies have examined whether this bias also expresses itself in more complex cognitive processes and behavior such as decision making. We recently introduced a variation of the Iowa Gambling Task which allowed us to document the influence of task-irrelevant emotional cues on rational decision making. The present study used a modified gambling task to investigate the impact of angry facial expressions on decision making in 38 individuals with a wide range of social anxiety. Participants were to find out which choices were (dis-) advantageous to maximize overall gain. To create a decision conflict between approach of reward and avoidance of fear-relevant angry faces, advantageous choices were associated with angry facial expressions, whereas disadvantageous choices were associated with happy facial expressions. Results indicated that higher social avoidance predicted less advantageous decisions in the beginning of the task, i.e., when contingencies were still uncertain. Interactions with specific skin conductance responses further clarified that this initial avoidance only occurred in combination with elevated responses before choosing an angry facial expressions. In addition, an interaction between high trait anxiety and elevated responses to early losses predicted faster learning of an advantageous strategy. These effects were independent of intelligence, general risky decision-making, self-reported state anxiety, and depression. Thus, socially avoidant individuals who respond emotionally to angry facial expressions are more likely to show avoidance of these faces under uncertainty. This novel laboratory paradigm may be an appropriate analog for central features of social anxiety.

An fMRI study of sex differences in regional activation to a verbal and a spatial task.

PubMed

Gur, R C; Alsop, D; Glahn, D; Petty, R; Swanson, C L; Maldjian, J A; Turetsky, B I; Detre, J A; Gee, J; Gur, R E

2000-09-01

Sex differences in cognitive performance have been documented, women performing better on some phonological tasks and men on spatial tasks. An earlier fMRI study suggested sex differences in distributed brain activation during phonological processing, with bilateral activation seen in women while men showed primarily left-lateralized activation. This blood oxygen level-dependent fMRI study examined sex differences (14 men, 13 women) in activation for a spatial task (judgment of line orientation) compared to a verbal-reasoning task (analogies) that does not typically show sex differences. Task difficulty was manipulated. Hypothesized ROI-based analysis documented the expected left-lateralized changes for the verbal task in the inferior parietal and planum temporal regions in both men and women, but only men showed right-lateralized increase for the spatial task in these regions. Image-based analysis revealed a distributed network of cortical regions activated by the tasks, which consisted of the lateral frontal, medial frontal, mid-temporal, occipitoparietal, and occipital regions. The activation was more left lateralized for the verbal and more right for the spatial tasks, but men also showed some left activation for the spatial task, which was not seen in women. Increased task difficulty produced more distributed activation for the verbal and more circumscribed activation for the spatial task. The results suggest that failure to activate the appropriate hemisphere in regions directly involved in task performance may explain certain sex differences in performance. They also extend, for a spatial task, the principle that bilateral activation in a distributed cognitive system underlies sex differences in performance. Copyright 2000 Academic Press.

Unhappiness Intensifies the Avoidance of Frequent Losses While Happiness Overcomes It.

PubMed

Yechiam, Eldad; Telpaz, Ariel; Krupenia, Stas; Rafaeli, Anat

2016-01-01

The implication of spontaneous and induced unhappiness to people's decision style is examined. It is postulated that unhappy individuals have a greater tendency to avoid frequent losses because these can have depleting effects, and unhappy individuals are more sensitive to such effects. This is evaluated in Study 1 by using an annoying customer call manipulation to induce negative affect; and by examining the effect of this manipulation on choices in an experiential decision task (the Iowa Gambling task). In Study 2 we examined the association between self-reported (un)happiness and choices on the same decision task. In Study 1 the induction of negative affect led to avoidance of choice alternatives with frequent losses, compared to those yielding rarer but larger losses. Specifically, this pertained to the advantageous alternatives with frequent vs. non-frequent losses. In Study 2 unhappiness was similarly associated with less exposure to frequent losses; while extreme high happiness was associated with no tendency to avoid frequent losses when these were part of an advantageous alternative. The findings clarify the role of happiness in decision making processes by indicating that unhappiness induces sensitivity to the frequency rather than to the total effect of negative events.

Mindfulness, Physical Activity and Avoidance of Secondhand Smoke: A Study of College Students in Shanghai.

PubMed

Gao, Yu; Shi, Lu

2015-08-21

To better understand the documented link between mindfulness and longevity, we examine the association between mindfulness and conscious avoidance of secondhand smoke (SHS), as well as the association between mindfulness and physical activity. In Shanghai University of Finance and Economics (SUFE) we surveyed a convenience sample of 1516 college freshmen. We measured mindfulness, weekly physical activity, and conscious avoidance of secondhand smoke, along with demographic and behavioral covariates. We used a multilevel logistic regression to test the association between mindfulness and conscious avoidance of secondhand smoke, and used a Tobit regression model to test the association between mindfulness and metabolic equivalent hours per week. In both models the home province of the student respondent was used as the cluster variable, and demographic and behavioral covariates, such as age, gender, smoking history, household registration status (urban vs. rural), the perceived smog frequency in their home towns, and the asthma diagnosis. The logistic regression of consciously avoiding SHS shows that a higher level of mindfulness was associated with an increase in the odds ratio of conscious SHS avoidance (logged odds: 0.22, standard error: 0.07, p < 0.01). The Tobit regression shows that a higher level of mindfulness was associated with more metabolic equivalent hours per week (Tobit coefficient: 4.09, standard error: 1.13, p < 0.001). This study is an innovative attempt to study the behavioral issue of secondhand smoke from the perspective of the potential victim, rather than the active smoker. The observed associational patterns here are consistent with previous findings that mindfulness is associated with healthier behaviors in obesity prevention and substance use. Research designs with interventions are needed to test the causal link between mindfulness and these healthy behaviors.

Mindfulness, Physical Activity and Avoidance of Secondhand Smoke: A Study of College Students in Shanghai

PubMed Central

Gao, Yu; Shi, Lu

2015-01-01

Introduction: To better understand the documented link between mindfulness and longevity, we examine the association between mindfulness and conscious avoidance of secondhand smoke (SHS), as well as the association between mindfulness and physical activity. Method: In Shanghai University of Finance and Economics (SUFE) we surveyed a convenience sample of 1516 college freshmen. We measured mindfulness, weekly physical activity, and conscious avoidance of secondhand smoke, along with demographic and behavioral covariates. We used a multilevel logistic regression to test the association between mindfulness and conscious avoidance of secondhand smoke, and used a Tobit regression model to test the association between mindfulness and metabolic equivalent hours per week. In both models the home province of the student respondent was used as the cluster variable, and demographic and behavioral covariates, such as age, gender, smoking history, household registration status (urban vs. rural), the perceived smog frequency in their home towns, and the asthma diagnosis. Results: The logistic regression of consciously avoiding SHS shows that a higher level of mindfulness was associated with an increase in the odds ratio of conscious SHS avoidance (logged odds: 0.22, standard error: 0.07, p < 0.01). The Tobit regression shows that a higher level of mindfulness was associated with more metabolic equivalent hours per week (Tobit coefficient: 4.09, standard error: 1.13, p < 0.001). Discussion: This study is an innovative attempt to study the behavioral issue of secondhand smoke from the perspective of the potential victim, rather than the active smoker. The observed associational patterns here are consistent with previous findings that mindfulness is associated with healthier behaviors in obesity prevention and substance use. Research designs with interventions are needed to test the causal link between mindfulness and these healthy behaviors. PMID:26308029

Sensorimotor Model of Obstacle Avoidance in Echolocating Bats

PubMed Central

Vanderelst, Dieter; Holderied, Marc W.; Peremans, Herbert

2015-01-01

Bat echolocation is an ability consisting of many subtasks such as navigation, prey detection and object recognition. Understanding the echolocation capabilities of bats comes down to isolating the minimal set of acoustic cues needed to complete each task. For some tasks, the minimal cues have already been identified. However, while a number of possible cues have been suggested, little is known about the minimal cues supporting obstacle avoidance in echolocating bats. In this paper, we propose that the Interaural Intensity Difference (IID) and travel time of the first millisecond of the echo train are sufficient cues for obstacle avoidance. We describe a simple control algorithm based on the use of these cues in combination with alternating ear positions modeled after the constant frequency bat Rhinolophus rouxii. Using spatial simulations (2D and 3D), we show that simple phonotaxis can steer a bat clear from obstacles without performing a reconstruction of the 3D layout of the scene. As such, this paper presents the first computationally explicit explanation for obstacle avoidance validated in complex simulated environments. Based on additional simulations modelling the FM bat Phyllostomus discolor, we conjecture that the proposed cues can be exploited by constant frequency (CF) bats and frequency modulated (FM) bats alike. We hypothesize that using a low level yet robust cue for obstacle avoidance allows bats to comply with the hard real-time constraints of this basic behaviour. PMID:26502063

Fear of movement and avoidance behaviour toward physical activity in chronic-fatigue syndrome and fibromyalgia: state of the art and implications for clinical practice.

PubMed

Nijs, Jo; Roussel, Nathalie; Van Oosterwijck, Jessica; De Kooning, Margot; Ickmans, Kelly; Struyf, Filip; Meeus, Mira; Lundberg, Mari

2013-08-01

Severe exacerbation of symptoms following physical activity is characteristic for chronic-fatigue syndrome (CFS) and fibromyalgia (FM). These exacerbations make it understandable for people with CFS and FM to develop fear of performing body movement or physical activity and consequently avoidance behaviour toward physical activity. The aims of this article were to review what measures are available for measuring fear of movement and avoidance behaviour, the prevalence fear of movement and avoidance behaviour toward physical activity and the therapeutic options with fear of movement and avoidance behaviour toward physical activity in patients with CFS and FM. The review revealed that fear of movement and avoidance behaviour toward physical activity is highly prevalent in both the CFS and FM population, and it is related to various clinical characteristics of CFS and FM, including symptom severity and self-reported quality of life and disability. It appears to be crucial for treatment (success) to identify CFS and FM patients displaying fear of movement and avoidance behaviour toward physical activity. Individually tailored cognitive behavioural therapy plus exercise training, depending on the patient's classification as avoiding or persisting, appears to be the most promising strategy for treating fear of movement and avoidance behaviour toward physical activity in patients with CFS and FM.

[Delayed reactions of active avoidance in white rats under conditions of an alternative choice].

PubMed

Ioseliani, T K; Sikharulidze, N I; Kadagishvili, A Ia; Mitashvili, E G

1995-01-01

It was shown that if the rats had been learned and then tested using conventional pain punishment of erroneous choice they were able to solve the problem of alternative choice only in the period of immediate action of conditioned stimuli. If the pain punishment for erroneously chosen compartment had not been applied in animal learning and testing, rats successfully solved the problem of alternative choice even after 5-second delay. Introduction of pain punishment led to the frustration of earlier elaborated delayed avoidance reactions. Analysis of the obtained results allows us to argue that the apparent incapability of white rats for solving the problems of delayed avoidance is caused by simultaneous action of two different mechanisms, i.e., those of the active and passive avoidance rather than short-term memory deficit.

Characterizing "fibrofog": Subjective appraisal, objective performance, and task-related brain activity during a working memory task.

PubMed

Walitt, Brian; Čeko, Marta; Khatiwada, Manish; Gracely, John L; Rayhan, Rakib; VanMeter, John W; Gracely, Richard H

2016-01-01

The subjective experience of cognitive dysfunction ("fibrofog") is common in fibromyalgia. This study investigated the relation between subjective appraisal of cognitive function, objective cognitive task performance, and brain activity during a cognitive task using functional magnetic resonance imaging (fMRI). Sixteen fibromyalgia patients and 13 healthy pain-free controls completed a battery of questionnaires, including the Multiple Ability Self-Report Questionnaire (MASQ), a measure of self-perceived cognitive difficulties. Participants were evaluated for working memory performance using a modified N-back working memory task while undergoing Blood Oxygen Level Dependent (BOLD) fMRI measurements. Fibromyalgia patients and controls did not differ in working memory performance. Subjective appraisal of cognitive function was associated with better performance (accuracy) on the working memory task in healthy controls but not in fibromyalgia patients. In fibromyalgia patients, increased perceived cognitive difficulty was positively correlated with the severity of their symptoms. BOLD response during the working memory task did not differ between the groups. BOLD response correlated with task accuracy in control subjects but not in fibromyalgia patients. Increased subjective cognitive impairment correlated with decreased BOLD response in both groups but in different anatomic regions. In conclusion, "fibrofog" appears to be better characterized by subjective rather than objective impairment. Neurologic correlates of this subjective experience of impairment might be separate from those involved in the performance of cognitive tasks.

In action or inaction? Social approach-avoidance tendencies in major depression.

PubMed

Radke, Sina; Güths, Franziska; André, Julia A; Müller, Bernhard W; de Bruijn, Ellen R A

2014-11-30

In depression, approach deficits often impair everyday social functioning, but empirical findings on performance-based measurements of approach-avoidance behavior remain conflicting. To investigate action tendencies in patients with depression, the current study used an explicit version of the Approach-Avoidance Task (AAT). In this task, participants responded to emotional faces by either pulling a joystick toward (approach) or pushing it away from themselves (avoid). Reaction times to happy and angry expressions with direct and averted gaze were assessed in 30 patients with major depressive disorder and 20 matched healthy controls. In contrast to healthy individuals, depressed patients did not show approach-avoidance tendencies, i.e., there was no dominant behavioral tendency and they reacted to happy and angry expressions likewise. These results indicate that behavioral adjustments to different emotional expressions, gaze directions or motivational demands were lacking in depression. Crucially, this distinguishes depressed patients not only from healthy individuals, but also from other clinical populations that demonstrate aberrant approach-avoidance tendencies, e.g., patients with social anxiety or psychopathy. As responding flexibly to different social signals is integral to social interactions, the absence of any social motivational tendencies seems maladaptive, but may also provide opportunities for modifying action tendencies in a therapeutic context. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Brain activity during divided and selective attention to auditory and visual sentence comprehension tasks

PubMed Central

Moisala, Mona; Salmela, Viljami; Salo, Emma; Carlson, Synnöve; Vuontela, Virve; Salonen, Oili; Alho, Kimmo

2015-01-01

Using functional magnetic resonance imaging (fMRI), we measured brain activity of human participants while they performed a sentence congruence judgment task in either the visual or auditory modality separately, or in both modalities simultaneously. Significant performance decrements were observed when attention was divided between the two modalities compared with when one modality was selectively attended. Compared with selective attention (i.e., single tasking), divided attention (i.e., dual-tasking) did not recruit additional cortical regions, but resulted in increased activity in medial and lateral frontal regions which were also activated by the component tasks when performed separately. Areas involved in semantic language processing were revealed predominantly in the left lateral prefrontal cortex by contrasting incongruent with congruent sentences. These areas also showed significant activity increases during divided attention in relation to selective attention. In the sensory cortices, no crossmodal inhibition was observed during divided attention when compared with selective attention to one modality. Our results suggest that the observed performance decrements during dual-tasking are due to interference of the two tasks because they utilize the same part of the cortex. Moreover, semantic dual-tasking did not appear to recruit additional brain areas in comparison with single tasking, and no crossmodal inhibition was observed during intermodal divided attention. PMID:25745395

Brain activity during divided and selective attention to auditory and visual sentence comprehension tasks.

PubMed

Moisala, Mona; Salmela, Viljami; Salo, Emma; Carlson, Synnöve; Vuontela, Virve; Salonen, Oili; Alho, Kimmo

2015-01-01

Using functional magnetic resonance imaging (fMRI), we measured brain activity of human participants while they performed a sentence congruence judgment task in either the visual or auditory modality separately, or in both modalities simultaneously. Significant performance decrements were observed when attention was divided between the two modalities compared with when one modality was selectively attended. Compared with selective attention (i.e., single tasking), divided attention (i.e., dual-tasking) did not recruit additional cortical regions, but resulted in increased activity in medial and lateral frontal regions which were also activated by the component tasks when performed separately. Areas involved in semantic language processing were revealed predominantly in the left lateral prefrontal cortex by contrasting incongruent with congruent sentences. These areas also showed significant activity increases during divided attention in relation to selective attention. In the sensory cortices, no crossmodal inhibition was observed during divided attention when compared with selective attention to one modality. Our results suggest that the observed performance decrements during dual-tasking are due to interference of the two tasks because they utilize the same part of the cortex. Moreover, semantic dual-tasking did not appear to recruit additional brain areas in comparison with single tasking, and no crossmodal inhibition was observed during intermodal divided attention.

[Effect of serotonin-modulated anticonsolidation protein on formation of long-term memory in carps Cyprinus carpio in the model of active avoidance learning].

PubMed

Garina, D V; Mekhtiev, A A

2014-01-01

Effect of serotonin-modulated anticonsolidation protein (SMAP) that has property of disturbing formation of memory trace in mammals and of learning and memory in teleost fish was studied in the model of active avoidance learning. The experiment was performed in three stages: (1) fry of carps Cyprinus carpio L. was injected intracerebrovenricularly with the SMAP protein at a dose of 0.3 μg/g; control individuals were administered with equal amount of the buffered saline for poikilothermic animals; (2) 24 h after the injection, fish were learnt during 8 sèances for 2 days the conditioned reflex of active avoidance; (3) 48 h after the learning the testing of the skill was performed. The administration of the protein was shown to lead to disturbance of reproduction of the skill in the fish: the latent time of the skill reproduction in experimental individuals exceeded that in control fish more than two times, while the number of individuals succeeding the task in the experimental group was non-significantly lower than in the control group. However, unlike mammals, injection of the SMAP protein in this model produced no effect on the process of learning in carps. Thus, there was first demonstrated the inhibiting effect of the SMAP protein whose concentration correlated positively with the content of the neurotransmitter serotonin in brain on consolidation of memory traces in teleost fish.

Top-down attentional control in spatially coincident stimuli enhances activity in both task-relevant and task-irrelevant regions of cortex

PubMed Central

Erickson, Kirk I.; Prakash, Ruchika Shaurya; Kim, Jennifer S.; Sutton, Bradley P.; Colcombe, Stanley J.; Kramer, Arthur F.

2010-01-01

Models of selective attention predict that focused attention to spatially contiguous stimuli may result in enhanced activity in areas of cortex specialized for processing task-relevant and task-irrelevant information. We examined this hypothesis by localizing color-sensitive areas (CSA) and word and letter sensitive areas of cortex and then examining modulation of these regions during performance of a modified version of the Stroop task in which target and distractors are spatially coincident. We report that only the incongruent condition with the highest cognitive demand showed increased activity in CSA relative to other conditions, indicating an attentional enhancement in target processing areas. We also found an enhancement of activity in one region sensitive to word/letter processing during the most cognitively demanding incongruent condition indicating greater processing of the distractor dimension. Correlations with performance revealed that top-down modulation during the task was critical for effective filtering of irrelevant information in conflict conditions. These results support predictions made by models of selective attention and suggest an important mechanism of top-down attentional control in spatially contiguous stimuli. PMID:18804123

The nucleus accumbens is involved in both the pursuit of social reward and the avoidance of social punishment.

PubMed

Kohls, Gregor; Perino, Michael T; Taylor, James M; Madva, Elizabeth N; Cayless, Sarah J; Troiani, Vanessa; Price, Elinora; Faja, Susan; Herrington, John D; Schultz, Robert T

2013-09-01

Human social motivation is characterized by the pursuit of social reward and the avoidance of social punishment. The ventral striatum/nucleus accumbens (VS/Nacc), in particular, has been implicated in the reward component of social motivation, i.e., the 'wanting' of social incentives like approval. However, it is unclear to what extent the VS/Nacc is involved in avoiding social punishment like disapproval, an intrinsically pleasant outcome. Thus, we conducted an event-related functional magnetic resonance imaging (fMRI) study using a social incentive delay task with dynamic video stimuli instead of static pictures as social incentives in order to examine participants' motivation for social reward gain and social punishment avoidance. As predicted, the anticipation of avoidable social punishment (i.e., disapproval) recruited the VS/Nacc in a manner that was similar to VS/Nacc activation observed during the anticipation of social reward gain (i.e., approval). Stronger VS/Nacc activity was accompanied by faster reaction times of the participants to obtain those desired outcomes. This data support the assumption that dynamic social incentives elicit robust VS/Nacc activity, which likely reflects motivation to obtain social reward and to avoid social punishment. Clinical implications regarding the involvement of the VS/Nacc in social motivation dysfunction in autism and social phobia are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Differences in the activation and co-activation ratios of the four subdivisions of trapezius between genders following a computer typing task.

PubMed

Szucs, Kimberly A; Molnar, Megan

2017-04-01

The aim of this study was to provide a description of gender differences of the activation patterns of the four subdivisions of the trapezius (clavicular, upper, middle, lower) following a 60min computer work task. Surface EMG was collected from these subdivisions from 21 healthy subjects during bilateral arm elevation pre-/post- task. Subjects completed a standardized 60min computer work task at a standard, ergonomic workstation. Normalized activation and activation ratios of each trapezius subdivision were compared between genders and condition with repeated measures ANOVAs. The interaction effect of Gender×Condition for upper trapezius% activation approached significance at p=0.051with males demonstrating greater activation post-task. The main effect of Condition was statistically significant for% activation of middle and lower trapezius (p<0.05), with both muscles demonstrating increase activation post-task. There was a statistically significant interaction effect of Gender×Condition for the Middle Trapezius/Upper Trapezius ratio and main effect of Condition for the Clavicular Trapezius/Upper Trapezius ratio, with a decreased ratio post-typing. Gender differences exist following 60min of a low force computer typing task. Imbalances in muscle activation and activation ratios following computer work may affect total shoulder kinematics and should be further explored. Copyright © 2017 Elsevier B.V. All rights reserved.

Individual Differences in Approach and Avoidance Inclinations Moderate the Effect of Self-Control Depletion on Ad-Lib Drinking

PubMed Central

Schlauch, Robert C.; Christensen, Rita L.; Derrick, Jaye L.; Crane, Cory A.; Collins, R. Lorraine

2015-01-01

Background The current study sought to examine how exerting self-control to inhibit stereotype use affects alcohol consumption. In addition, we sought to expand previous findings via examination of how individual differences in motivations to approach or avoid alcohol consumption interact with self-control depletion to determine the regulation of ad-lib drinking behavior. Methods Sixty-one social drinkers (31 female) were recruited to participate in a socially relevant self-control depletion task in which they were randomly assigned to one of two creative writing conditions: 1) the self-control depletion condition with explicit instructions to refrain from using stereotypes, or 2) the non-depletion condition in which no instructions were given regarding the use of stereotypes. Participants then completed an ad-lib drinking task and self-report questionnaires pertaining to their motivation to consume alcohol. Results As predicted, results indicated a significant three-way interaction between depletion condition, approach inclinations, and avoidance inclinations. Specifically, self-control depletion predicted greater drinking disinhibition (i.e., mean sip size, total alcohol consumption) only among participants high in both approach and avoidance. Conclusions Taken together, results from the current study highlight the importance of both approach and avoidance inclinations in the failure to regulate alcohol consumption following a routine, socially relevant form of self-control depletion. Our results also suggest that the high approach / high avoidance motivational profile may predict the greatest risk among those actively trying to regulate their drinking. PMID:26756800

Neural substrates of approach-avoidance conflict decision-making.

PubMed

Aupperle, Robin L; Melrose, Andrew J; Francisco, Alex; Paulus, Martin P; Stein, Murray B

2015-02-01

Animal approach-avoidance conflict paradigms have been used extensively to operationalize anxiety, quantify the effects of anxiolytic agents, and probe the neural basis of fear and anxiety. Results from human neuroimaging studies support that a frontal-striatal-amygdala neural circuitry is important for approach-avoidance learning. However, the neural basis of decision-making is much less clear in this context. Thus, we combined a recently developed human approach-avoidance paradigm with functional magnetic resonance imaging (fMRI) to identify neural substrates underlying approach-avoidance conflict decision-making. Fifteen healthy adults completed the approach-avoidance conflict (AAC) paradigm during fMRI. Analyses of variance were used to compare conflict to nonconflict (avoid-threat and approach-reward) conditions and to compare level of reward points offered during the decision phase. Trial-by-trial amplitude modulation analyses were used to delineate brain areas underlying decision-making in the context of approach/avoidance behavior. Conflict trials as compared to the nonconflict trials elicited greater activation within bilateral anterior cingulate cortex, anterior insula, and caudate, as well as right dorsolateral prefrontal cortex (PFC). Right caudate and lateral PFC activation was modulated by level of reward offered. Individuals who showed greater caudate activation exhibited less approach behavior. On a trial-by-trial basis, greater right lateral PFC activation related to less approach behavior. Taken together, results suggest that the degree of activation within prefrontal-striatal-insula circuitry determines the degree of approach versus avoidance decision-making. Moreover, the degree of caudate and lateral PFC activation related to individual differences in approach-avoidance decision-making. Therefore, the approach-avoidance conflict paradigm is ideally suited to probe anxiety-related processing differences during approach-avoidance decision

Avoidance of wind farms by harbour seals is limited to pile driving activities.

PubMed

Russell, Debbie J F; Hastie, Gordon D; Thompson, David; Janik, Vincent M; Hammond, Philip S; Scott-Hayward, Lindesay A S; Matthiopoulos, Jason; Jones, Esther L; McConnell, Bernie J

2016-12-01

As part of global efforts to reduce dependence on carbon-based energy sources there has been a rapid increase in the installation of renewable energy devices. The installation and operation of these devices can result in conflicts with wildlife. In the marine environment, mammals may avoid wind farms that are under construction or operating. Such avoidance may lead to more time spent travelling or displacement from key habitats. A paucity of data on at-sea movements of marine mammals around wind farms limits our understanding of the nature of their potential impacts.Here, we present the results of a telemetry study on harbour seals Phoca vitulina in The Wash, south-east England, an area where wind farms are being constructed using impact pile driving. We investigated whether seals avoid wind farms during operation, construction in its entirety, or during piling activity. The study was carried out using historical telemetry data collected prior to any wind farm development and telemetry data collected in 2012 during the construction of one wind farm and the operation of another.Within an operational wind farm, there was a close-to-significant increase in seal usage compared to prior to wind farm development. However, the wind farm was at the edge of a large area of increased usage, so the presence of the wind farm was unlikely to be the cause.There was no significant displacement during construction as a whole. However, during piling, seal usage (abundance) was significantly reduced up to 25 km from the piling activity; within 25 km of the centre of the wind farm, there was a 19 to 83% (95% confidence intervals) decrease in usage compared to during breaks in piling, equating to a mean estimated displacement of 440 individuals. This amounts to significant displacement starting from predicted received levels of between 166 and 178 dB re 1 μPa (p-p) . Displacement was limited to piling activity; within 2 h of cessation of pile driving, seals were distributed as

Implicit Approach-Avoidance Associations for Craved Food Cues

ERIC Educational Resources Information Center

Kemps, Eva; Tiggemann, Marika; Martin, Rachel; Elliott, Mecia

2013-01-01

Implicit approach associations are well documented for substances such as alcohol, tobacco, and illicit drugs. This study reports two experiments designed to establish and modify such associations specifically in the food craving domain. Experiment 1 used a pictorial implicit association task to examine approach-avoidance associations with…

Gaming is related to enhanced working memory performance and task-related cortical activity.

PubMed

Moisala, M; Salmela, V; Hietajärvi, L; Carlson, S; Vuontela, V; Lonka, K; Hakkarainen, K; Salmela-Aro, K; Alho, K

2017-01-15

Gaming experience has been suggested to lead to performance enhancements in a wide variety of working memory tasks. Previous studies have, however, mostly focused on adult expert gamers and have not included measurements of both behavioral performance and brain activity. In the current study, 167 adolescents and young adults (aged 13-24 years) with different amounts of gaming experience performed an n-back working memory task with vowels, with the sensory modality of the vowel stream switching between audition and vision at random intervals. We studied the relationship between self-reported daily gaming activity, working memory (n-back) task performance and related brain activity measured using functional magnetic resonance imaging (fMRI). The results revealed that the extent of daily gaming activity was related to enhancements in both performance accuracy and speed during the most demanding (2-back) level of the working memory task. This improved working memory performance was accompanied by enhanced recruitment of a fronto-parietal cortical network, especially the dorsolateral prefrontal cortex. In contrast, during the less demanding (1-back) level of the task, gaming was associated with decreased activity in the same cortical regions. Our results suggest that a greater degree of daily gaming experience is associated with better working memory functioning and task difficulty-dependent modulation in fronto-parietal brain activity already in adolescence and even when non-expert gamers are studied. The direction of causality within this association cannot be inferred with certainty due to the correlational nature of the current study. Copyright © 2016 Elsevier B.V. All rights reserved.

Task-dependent modulations of prefrontal and hippocampal activity during intrinsic word production.

PubMed

Whitney, Carin; Weis, Susanne; Krings, Timo; Huber, Walter; Grossman, Murray; Kircher, Tilo

2009-04-01

Functional imaging studies of single word production have consistently reported activation of the lateral prefrontal and cingulate cortex. Its contribution has been shown to be sensitive to task demands, which can be manipulated by the degree of response specification. Compared with classical verbal fluency, free word association relies less on response restrictions but to a greater extent on associative binding processes, usually subserved by the hippocampus. To elucidate the relevance of the frontal and medial-temporal areas during verbal retrieval tasks, we applied varying degrees of response specification. During fMRI data acquisition, 18 subjects performed a free verbal association (FVA), a semantic verbal fluency (SVF) task, and a phonological verbal fluency (PVF) task. Externally guided word production served as a baseline condition to control for basic articulatory and reading processes. As expected, increased brain activity was observed in the left lateral and bilateral medial frontal cortices for SVF and PVF. The anterior cingulate gyrus was the only structure common to both fluency tasks in direct comparison to the less restricted FVA task. The hippocampus was engaged during associative and semantic retrieval. Interestingly, hippocampal activity was selectively evident during FVA in direct comparison to SVF when it was controlled for stimulus-response relations. The current data confirm the role of the left prefrontal-cingulate network in constrained word production. Hippocampal activity during spontaneous word production is a novel finding and seems to be dependent on the retrieval process (free vs. constrained) rather than the variety of stimulus-response relationships that is involved.

Passive versus active hazard detection and avoidance systems

NASA Astrophysics Data System (ADS)

Neveu, D.; Mercier, G.; Hamel, J.-F.; Simard Bilodeau, V.; Woicke, S.; Alger, M.; Beaudette, D.

2015-06-01

Upcoming planetary exploration missions will require advanced guidance, navigation and control technologies to reach landing sites with high precision and safety. Various technologies are currently in development to meet that goal. Some technologies rely on passive sensors and benefit from the low mass and power of such solutions while others rely on active sensors and benefit from an improved robustness and accuracy. This paper presents two different hazard detection and avoidance (HDA) system design approaches. The first architecture relies only on a camera as the passive HDA sensor while the second relies, in addition, on a Lidar as the active HDA sensor. Both options use in common an innovative hazard map fusion algorithm aiming at identifying the safest landing locations. This paper presents the simulation tools and reports the closed-loop software simulation results obtained using each design option. The paper also reports the Monte Carlo simulation campaign that was used to assess the robustness of each design option. The performance of each design option is compared against each other in terms of performance criteria such as percentage of success, mean distance to nearest hazard, etc. The applicability of each design option to planetary exploration missions is also discussed.

Unhappiness Intensifies the Avoidance of Frequent Losses While Happiness Overcomes It

PubMed Central

Yechiam, Eldad; Telpaz, Ariel; Krupenia, Stas; Rafaeli, Anat

2016-01-01

The implication of spontaneous and induced unhappiness to people's decision style is examined. It is postulated that unhappy individuals have a greater tendency to avoid frequent losses because these can have depleting effects, and unhappy individuals are more sensitive to such effects. This is evaluated in Study 1 by using an annoying customer call manipulation to induce negative affect; and by examining the effect of this manipulation on choices in an experiential decision task (the Iowa Gambling task). In Study 2 we examined the association between self-reported (un)happiness and choices on the same decision task. In Study 1 the induction of negative affect led to avoidance of choice alternatives with frequent losses, compared to those yielding rarer but larger losses. Specifically, this pertained to the advantageous alternatives with frequent vs. non-frequent losses. In Study 2 unhappiness was similarly associated with less exposure to frequent losses; while extreme high happiness was associated with no tendency to avoid frequent losses when these were part of an advantageous alternative. The findings clarify the role of happiness in decision making processes by indicating that unhappiness induces sensitivity to the frequency rather than to the total effect of negative events. PMID:27853443

Integrating the Use of Interdisciplinary Learning Activity Task in Creating Students' Mathematical Knowledge

ERIC Educational Resources Information Center

Mahanin, Hajah Umisuzimah Haji; Shahrill, Masitah; Tan, Abby; Mahadi, Mar Aswandi

2017-01-01

This study investigated the use of interdisciplinary learning activity task to construct students' knowledge in Mathematics, specifically on the topic of scale drawing application. The learning activity task involved more than one academic discipline, which is Mathematics, English Language, Art, Geography and integrating the Brunei Darussalam…

Passive avoidance is linked to impaired fear extinction in humans

PubMed Central

Cornwell, Brian R.; Overstreet, Cassie; Krimsky, Marissa; Grillon, Christian

2013-01-01

Conventional wisdom dictates we must face our fears to conquer them. This idea is embodied in exposure-based treatments for anxiety disorders, where the intent of exposure is to reverse a history of avoidant behavior that is thought to fuel a patient’s irrational fears. We tested in humans the relationship between fear and avoidance by combining Pavlovian differential fear conditioning with a novel task for quantifying spontaneous passive avoidant behavior. During self-guided navigation in virtual reality following de novo fear conditioning, we observed participants keeping their distance from the feared object. At the individual level, passive avoidant behavior was highly associated with maladaptive fear expression (fear-potentiated startle) during late extinction training, indicating that extinction learning was impaired following a brief episode of avoidance. Avoidant behavior, however, was not related to initial acquired fear, raising doubt about a straightforward link between physiological fear and behavioral avoidance. We conclude that a deeper understanding of what motivates avoidance may offer a target for early intervention, before fears transition from the rational to the irrational. PMID:23427168

Neural substrates of approach-avoidance conflict decision-making

PubMed Central

Aupperle, Robin L.; Melrose, Andrew J.; Francisco, Alex; Paulus, Martin P.; Stein, Murray B.

2014-01-01

Animal approach-avoidance conflict paradigms have been used extensively to operationalize anxiety, quantify the effects of anxiolytic agents, and probe the neural basis of fear and anxiety. Results from human neuroimaging studies support that a frontal-striatal-amygdala neural circuitry is important for approach-avoidance learning. However, the neural basis of decision-making is much less clear in this context. Thus, we combined a recently developed human approach-avoidance paradigm with functional magnetic resonance imaging (fMRI) to identify neural substrates underlying approach-avoidance conflict decision-making. Fifteen healthy adults completed the approach-avoidance conflict (AAC) paradigm during fMRI. Analyses of variance were used to compare conflict to non-conflict (avoid-threat and approach-reward) conditions and to compare level of reward points offered during the decision phase. Trial-by-trial amplitude modulation analyses were used to delineate brain areas underlying decision-making in the context of approach/avoidance behavior. Conflict trials as compared to the non-conflict trials elicited greater activation within bilateral anterior cingulate cortex (ACC), anterior insula, and caudate, as well as right dorsolateral prefrontal cortex. Right caudate and lateral PFC activation was modulated by level of reward offered. Individuals who showed greater caudate activation exhibited less approach behavior. On a trial-by-trial basis, greater right lateral PFC activation related to less approach behavior. Taken together, results suggest that the degree of activation within prefrontal-striatal-insula circuitry determines the degree of approach versus avoidance decision-making. Moreover, the degree of caudate and lateral PFC activation is related to individual differences in approach-avoidance decision-making. Therefore, the AAC paradigm is ideally suited to probe anxiety-related processing differences during approach-avoidance decision-making. PMID:25224633

Acupuncture inhibits the decrease in brain catecholamine contents and the impairment of passive avoidance task in ovariectomized mice.

PubMed

Toriizuka, K; Okumura, M; Iijima, K; Haruyama, K; Cyong, J C

1999-01-01

The effects of acupuncture on the disorders elicited by abnormalities of endocrine system were investigated in ovariectomized mice. Female mice (strain; C57BL/6) were ovariectomized (OVX) and acupuncture points, Shenshu ([Japanese pictograph see text] : BL23) on both side of the back were continuously stimulated by subcutaneous needles for 20 days. After completion of experimental sessions, animals were sacrificed and specific brain regions were assayed for catecholamine contents by high performance liquid chromatography with electro chemical detector (ECD-HPLC). The mitogenic activities of splenic lymphocytes were measured by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTS) assay and alkaline phosphatase (ALP) assay. Furthermore, the effects of needle stimulation on learning and memory ability were studied by the step-through type passive avoidance test. Norepinephrine and dopamine contents in the frontoparietal cerebral cortex, ventral hippocampus and olfactory bulb were decreased in the OVX group, and both MTS activity and ALP activity were decreased 20 days after ovariectomy. The mean latent period was also shortened in the passive avoidance test in the OVX group. However, applying needle stimulation increased norepinephrine and dopamine contents in the brain regions, and enhanced mitogenic activities of splenic lymphocytes. The stimulation also improved memory-related behavior. It was concluded from this study that after mice were stimulated by subcutaneous needle insertion, overall changes were observed in central nervous system (including retention of memory) and immune functions. The study suggests that acupuncture improves the memory loss and decrease of immune responses accompanying aging and/or menopause, and the that it may have an important role in medical care for the elderly.

Neural Correlates of Attentional Flexibility during Approach and Avoidance Motivation

PubMed Central

Calcott, Rebecca D.; Berkman, Elliot T.

2015-01-01

Dynamic, momentary approach or avoidance motivational states have downstream effects on eventual goal success and overall well being, but there is still uncertainty about how those states affect the proximal neurocognitive processes (e.g., attention) that mediate the longer-term effects. Attentional flexibility, or the ability to switch between different attentional foci, is one such neurocognitive process that influences outcomes in the long run. The present study examined how approach and avoidance motivational states affect the neural processes involved in attentional flexibility using fMRI with the aim of determining whether flexibility operates via different neural mechanisms under these different states. Attentional flexibility was operationalized as subjects’ ability to switch between global and local stimulus features. In addition to subjects’ motivational state, the task context was manipulated by varying the ratio of global to local trials in a block in light of recent findings about the moderating role of context on motivation-related differences in attentional flexibility. The neural processes involved in attentional flexibility differ under approach versus avoidance states. First, differences in the preparatory activity in key brain regions suggested that subjects’ preparedness to switch was influenced by motivational state (anterior insula) and the interaction between motivation and context (superior temporal gyrus, inferior parietal lobule). Additionally, we observed motivation-related differences the anterior cingulate cortex during switching. These results provide initial evidence that motivation-induced behavioral changes may arise via different mechanisms in approach versus avoidance motivational states. PMID:26000735

Neural Correlates of Attentional Flexibility during Approach and Avoidance Motivation.

PubMed

Calcott, Rebecca D; Berkman, Elliot T

2015-01-01

Dynamic, momentary approach or avoidance motivational states have downstream effects on eventual goal success and overall well being, but there is still uncertainty about how those states affect the proximal neurocognitive processes (e.g., attention) that mediate the longer-term effects. Attentional flexibility, or the ability to switch between different attentional foci, is one such neurocognitive process that influences outcomes in the long run. The present study examined how approach and avoidance motivational states affect the neural processes involved in attentional flexibility using fMRI with the aim of determining whether flexibility operates via different neural mechanisms under these different states. Attentional flexibility was operationalized as subjects' ability to switch between global and local stimulus features. In addition to subjects' motivational state, the task context was manipulated by varying the ratio of global to local trials in a block in light of recent findings about the moderating role of context on motivation-related differences in attentional flexibility. The neural processes involved in attentional flexibility differ under approach versus avoidance states. First, differences in the preparatory activity in key brain regions suggested that subjects' preparedness to switch was influenced by motivational state (anterior insula) and the interaction between motivation and context (superior temporal gyrus, inferior parietal lobule). Additionally, we observed motivation-related differences the anterior cingulate cortex during switching. These results provide initial evidence that motivation-induced behavioral changes may arise via different mechanisms in approach versus avoidance motivational states.

Avoiding the conflict: Metacognitive awareness drives the selection of low-demand contexts.

PubMed

Desender, Kobe; Buc Calderon, Cristian; Van Opstal, Filip; Van den Bussche, Eva

2017-07-01

Previous research attempted to explain how humans strategically adapt behavior in order to achieve successful task performance. Recently, it has been suggested that 1 potential strategy is to avoid tasks that are too demanding. Here, we report 3 experiments that investigate the empirically neglected role of metacognitive awareness in this process. In these experiments, participants could freely choose between performing a task in either a high-demand or a low-demand context. Using subliminal priming, we ensured that participants were not aware of the visual stimuli creating these different demand contexts. Our results showed that participants who noticed a difference in task difficulty (i.e., metacognitive aware participants) developed a clear preference for the low-demand context. In contrast, participants who experienced no difference in task difficulty (i.e., metacognitive unaware participants) based their choices on variables unrelated to cognitive demand (e.g., the color or location associated with a context), and did not develop a preference for the low-demand context. Crucially, this pattern was found despite identical task performance in both metacognitive awareness groups. A multiple regression approach confirmed that metacognitive awareness was the main factor driving the preference for low-demand contexts. These results argue for an important role of metacognitive awareness in the strategic avoidance of demanding tasks. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Vagus nerve stimulation ameliorated deficits in one-way active avoidance learning and stimulated hippocampal neurogenesis in bulbectomized rats.

PubMed

Gebhardt, Nils; Bär, Karl-Jürgen; Boettger, Michael K; Grecksch, Gisela; Keilhoff, Gerburg; Reichart, Rupert; Becker, Axel

2013-01-01

Vagus nerve stimulation (VNS) has been introduced as a therapeutic option for treatment-resistant depression. The neural and chemical mechanisms responsible for the effects of VNS are largely unclear. Bilateral removal of the olfactory bulbs (OBX) is a validated animal model in depression research. We studied the effects of vagus nerve stimulation (VNS) on disturbed one-way active avoidance learning and neurogenesis in the hippocampal dentate gyrus of rats. After a stimulation period of 3 weeks, OBX rats acquired the learning task as controls. In addition, the OBX-related decrease of neuronal differentiated BrdU positive cells in the dentate gyrus was prevented by VNS. This suggests that chronic VNS and changes in hippocampal neurogenesis induced by VNS may also account for the amelioration of behavioral deficits in OBX rats. To the best of our knowledge, this is the first report on the restorative effects of VNS on behavioral function in an animal model of depression that can be compared with the effects of antidepressants. Copyright © 2013 Elsevier Inc. All rights reserved.

Is Neural Activity Detected by ERP-Based Brain-Computer Interfaces Task Specific?

PubMed

Wenzel, Markus A; Almeida, Inês; Blankertz, Benjamin

2016-01-01

Brain-computer interfaces (BCIs) that are based on event-related potentials (ERPs) can estimate to which stimulus a user pays particular attention. In typical BCIs, the user silently counts the selected stimulus (which is repeatedly presented among other stimuli) in order to focus the attention. The stimulus of interest is then inferred from the electroencephalogram (EEG). Detecting attention allocation implicitly could be also beneficial for human-computer interaction (HCI), because it would allow software to adapt to the user's interest. However, a counting task would be inappropriate for the envisaged implicit application in HCI. Therefore, the question was addressed if the detectable neural activity is specific for silent counting, or if it can be evoked also by other tasks that direct the attention to certain stimuli. Thirteen people performed a silent counting, an arithmetic and a memory task. The tasks required the subjects to pay particular attention to target stimuli of a random color. The stimulus presentation was the same in all three tasks, which allowed a direct comparison of the experimental conditions. Classifiers that were trained to detect the targets in one task, according to patterns present in the EEG signal, could detect targets in all other tasks (irrespective of some task-related differences in the EEG). The neural activity detected by the classifiers is not strictly task specific but can be generalized over tasks and is presumably a result of the attention allocation or of the augmented workload. The results may hold promise for the transfer of classification algorithms from BCI research to implicit relevance detection in HCI.

Gaze direction differentially affects avoidance tendencies to happy and angry faces in socially anxious individuals.

PubMed

Roelofs, Karin; Putman, Peter; Schouten, Sonja; Lange, Wolf-Gero; Volman, Inge; Rinck, Mike

2010-04-01

Increasing evidence indicates that eye gaze direction affects the processing of emotional faces in anxious individuals. However, the effects of eye gaze direction on the behavioral responses elicited by emotional faces, such as avoidance behavior, remain largely unexplored. We administered an Approach-Avoidance Task (AAT) in high (HSA) and low socially anxious (LSA) individuals. All participants responded to photographs of angry, happy and neutral faces (presented with direct and averted gaze), by either pushing a joystick away from them (avoidance) or pulling it towards them (approach). Compared to LSA, HSA were faster in avoiding than approaching angry faces. Most crucially, this avoidance tendency was only present when the perceived anger was directed towards the subject (direct gaze) and not when the gaze of the face-stimulus was averted. In contrast, HSA individuals tended to avoid happy faces irrespectively of gaze direction. Neutral faces elicited no approach-avoidance tendencies. Thus avoidance of angry faces in social anxiety as measured by AA-tasks reflects avoidance of subject-directed anger and not of negative stimuli in general. In addition, although both anger and joy are considered to reflect approach-related emotions, gaze direction did not affect HSA's avoidance of happy faces, suggesting differential mechanisms affecting responses to happy and angry faces in social anxiety. 2009 Elsevier Ltd. All rights reserved.

Avoidance-related EEG asymmetry predicts circulating interleukin-6.

PubMed

Shields, Grant S; Moons, Wesley G

2016-03-01

Recent research has linked avoidance-oriented motivational states to elevated pro-inflammatory cytokine levels. According to one of many theories regarding the association between avoidance and cytokine levels, because the evolutionarily basic avoidance system may be activated when an organism is threatened or overwhelmed, an associated inflammatory response may be adaptive for dealing with potential injury in such threatening situations. To examine this hypothesis, we tested whether the neural correlate of avoidance motivation associates with baseline levels of the circulating pro-inflammatory cytokine interleukin-6 (IL-6). Controlling for covariates, greater resting neural activity in the right frontal cortex relative to the left frontal cortex-the neural correlate of avoidance motivation-was associated with baseline IL-6. These results thus support the hypothesis that the avoidance motivational system may be closely linked to systemic inflammatory activity. (c) 2016 APA, all rights reserved).

Inhibition of memory consolidation by antibodies against cell adhesion molecules after active avoidance conditioning in zebrafish.

PubMed

Pradel, G; Schachner, M; Schmidt, R

1999-05-01

Cell adhesion molecules are expected to play an important role in long-term storage of information in the central nervous system. Several of these glycoproteins, such as NCAM, L1, and the ependymins, express the HNK-1 carbohydrate structure, which is known to be involved in cell-cell and cell-matrix interactions. To investigate the contribution of the HNK-1 epitope and the secretory glycoproteins ependymins to memory formation in zebrafish (Brachydanio rerio), we developed an active avoidance conditioning paradigm. Zebrafish were trained in a shuttle-box to cross a hurdle, to avoid mild electric shocks following a conditioning light signal. One hour after acquisition of the task, zebrafish were injected intracerebroventricularly with monoclonal antibodies against the HNK-1 epitope or polyclonal antibodies against ependymins. Control fish received immunoglobulins G (IgGs) from nonimmune rat serum or the monoclonal antibody C183 against an unrelated cell-surface protein of the cyprinid brain. Two days later, injected zebrafish were tested for recall, and for quantitative evaluation a retention score (RS), ranging from 1.0 for immediate recall to 0.0, indicating no saving, was calculated. The average RS of anti-HNK-1-injected fish (RS = 0.30) and anti-ependymin-injected fish (0.24) were significantly different from the RS of uninjected fish (0.77), of controls injected with nonimmune serum IgGs (0.68), of C183-injected controls (0.78), and of overtrained fish injected with anti-HNK-1 antibodies (0.81). Anti-HNK-1 and anti-ependymin antibodies were characterized by Western blot analyses of subcellular brain fractions and immunohistochemical staining of the zebrafish optic tectum. Our data suggest that the antibodies influence cell recognition events at synaptic membranes and/or associated intracellular signaling cascades, and thereby block memory consolidation.

Characterizing “fibrofog”: Subjective appraisal, objective performance, and task-related brain activity during a working memory task

PubMed Central

Walitt, Brian; Čeko, Marta; Khatiwada, Manish; Gracely, John L.; Rayhan, Rakib; VanMeter, John W.; Gracely, Richard H.

2016-01-01

The subjective experience of cognitive dysfunction (“fibrofog”) is common in fibromyalgia. This study investigated the relation between subjective appraisal of cognitive function, objective cognitive task performance, and brain activity during a cognitive task using functional magnetic resonance imaging (fMRI). Sixteen fibromyalgia patients and 13 healthy pain-free controls completed a battery of questionnaires, including the Multiple Ability Self-Report Questionnaire (MASQ), a measure of self-perceived cognitive difficulties. Participants were evaluated for working memory performance using a modified N-back working memory task while undergoing Blood Oxygen Level Dependent (BOLD) fMRI measurements. Fibromyalgia patients and controls did not differ in working memory performance. Subjective appraisal of cognitive function was associated with better performance (accuracy) on the working memory task in healthy controls but not in fibromyalgia patients. In fibromyalgia patients, increased perceived cognitive difficulty was positively correlated with the severity of their symptoms. BOLD response during the working memory task did not differ between the groups. BOLD response correlated with task accuracy in control subjects but not in fibromyalgia patients. Increased subjective cognitive impairment correlated with decreased BOLD response in both groups but in different anatomic regions. In conclusion, “fibrofog” appears to be better characterized by subjective rather than objective impairment. Neurologic correlates of this subjective experience of impairment might be separate from those involved in the performance of cognitive tasks. PMID:26955513

Differences in neural activation as a function of risk-taking task parameters

PubMed Central

Congdon, Eliza; Bato, Angelica A.; Schonberg, Tom; Mumford, Jeanette A.; Karlsgodt, Katherine H.; Sabb, Fred W.; London, Edythe D.; Cannon, Tyrone D.; Bilder, Robert M.; Poldrack, Russell A.

2013-01-01

Despite evidence supporting a relationship between impulsivity and naturalistic risk-taking, the relationship of impulsivity with laboratory-based measures of risky decision-making remains unclear. One factor contributing to this gap in our understanding is the degree to which different risky decision-making tasks vary in their details. We conducted an fMRI investigation of the Angling Risk Task (ART), which is an improved behavioral measure of risky decision-making. In order to examine whether the observed pattern of neural activation was specific to the ART or generalizable, we also examined correlates of the Balloon Analog Risk Taking (BART) task in the same sample of 23 healthy adults. Exploratory analyses were conducted to examine the relationship between neural activation, performance, impulsivity and self-reported risk-taking. While activation in a valuation network was associated with reward tracking during the ART but not the BART, increased fronto-cingulate activation was seen during risky choice trials in the BART as compared to the ART. Thus, neural activation during risky decision-making trials differed between the two tasks, and this observation was likely driven by differences in task parameters, namely the absence vs. presence of ambiguity and/or stationary vs. increasing probability of loss on the ART and BART, respectively. Exploratory association analyses suggest that sensitivity of neural response to the magnitude of potential reward during the ART was associated with a suboptimal performance strategy, higher scores on a scale of dysfunctional impulsivity (DI) and a greater likelihood of engaging in risky behaviors, while this pattern was not seen for the BART. Our results suggest that the ART is decomposable and associated with distinct patterns of neural activation; this represents a preliminary step toward characterizing a behavioral measure of risky decision-making that may support a better understanding of naturalistic risk-taking. PMID

Differences in neural activation as a function of risk-taking task parameters.

PubMed

Congdon, Eliza; Bato, Angelica A; Schonberg, Tom; Mumford, Jeanette A; Karlsgodt, Katherine H; Sabb, Fred W; London, Edythe D; Cannon, Tyrone D; Bilder, Robert M; Poldrack, Russell A

2013-01-01

Despite evidence supporting a relationship between impulsivity and naturalistic risk-taking, the relationship of impulsivity with laboratory-based measures of risky decision-making remains unclear. One factor contributing to this gap in our understanding is the degree to which different risky decision-making tasks vary in their details. We conducted an fMRI investigation of the Angling Risk Task (ART), which is an improved behavioral measure of risky decision-making. In order to examine whether the observed pattern of neural activation was specific to the ART or generalizable, we also examined correlates of the Balloon Analog Risk Taking (BART) task in the same sample of 23 healthy adults. Exploratory analyses were conducted to examine the relationship between neural activation, performance, impulsivity and self-reported risk-taking. While activation in a valuation network was associated with reward tracking during the ART but not the BART, increased fronto-cingulate activation was seen during risky choice trials in the BART as compared to the ART. Thus, neural activation during risky decision-making trials differed between the two tasks, and this observation was likely driven by differences in task parameters, namely the absence vs. presence of ambiguity and/or stationary vs. increasing probability of loss on the ART and BART, respectively. Exploratory association analyses suggest that sensitivity of neural response to the magnitude of potential reward during the ART was associated with a suboptimal performance strategy, higher scores on a scale of dysfunctional impulsivity (DI) and a greater likelihood of engaging in risky behaviors, while this pattern was not seen for the BART. Our results suggest that the ART is decomposable and associated with distinct patterns of neural activation; this represents a preliminary step toward characterizing a behavioral measure of risky decision-making that may support a better understanding of naturalistic risk-taking.

A Quantitative Relationship between Signal Detection in Attention and Approach/Avoidance Behavior.

PubMed

Viswanathan, Vijay; Sheppard, John P; Kim, Byoung W; Plantz, Christopher L; Ying, Hao; Lee, Myung J; Raman, Kalyan; Mulhern, Frank J; Block, Martin P; Calder, Bobby; Lee, Sang; Mortensen, Dale T; Blood, Anne J; Breiter, Hans C

2017-01-01

This study examines how the domains of reward and attention, which are often studied as independent processes, in fact interact at a systems level. We operationalize divided attention with a continuous performance task and variables from signal detection theory (SDT), and reward/aversion with a keypress task measuring approach/avoidance in the framework of relative preference theory (RPT). Independent experiments with the same subjects showed a significant association between one SDT and two RPT variables, visualized as a three-dimensional structure. Holding one of these three variables constant, further showed a significant relationship between a loss aversion-like metric from the approach/avoidance task, and the response bias observed during the divided attention task. These results indicate that a more liberal response bias under signal detection (i.e., a higher tolerance for noise, resulting in a greater proportion of false alarms) is associated with higher "loss aversion." Furthermore, our functional model suggests a mechanism for processing constraints with divided attention and reward/aversion. Together, our results argue for a systematic relationship between divided attention and reward/aversion processing in humans.

A methodology for assessing the effect of correlations among muscle synergy activations on task-discriminating information.

PubMed

Delis, Ioannis; Berret, Bastien; Pozzo, Thierry; Panzeri, Stefano

2013-01-01

Muscle synergies have been hypothesized to be the building blocks used by the central nervous system to generate movement. According to this hypothesis, the accomplishment of various motor tasks relies on the ability of the motor system to recruit a small set of synergies on a single-trial basis and combine them in a task-dependent manner. It is conceivable that this requires a fine tuning of the trial-to-trial relationships between the synergy activations. Here we develop an analytical methodology to address the nature and functional role of trial-to-trial correlations between synergy activations, which is designed to help to better understand how these correlations may contribute to generating appropriate motor behavior. The algorithm we propose first divides correlations between muscle synergies into types (noise correlations, quantifying the trial-to-trial covariations of synergy activations at fixed task, and signal correlations, quantifying the similarity of task tuning of the trial-averaged activation coefficients of different synergies), and then uses single-trial methods (task-decoding and information theory) to quantify their overall effect on the task-discriminating information carried by muscle synergy activations. We apply the method to both synchronous and time-varying synergies and exemplify it on electromyographic data recorded during performance of reaching movements in different directions. Our method reveals the robust presence of information-enhancing patterns of signal and noise correlations among pairs of synchronous synergies, and shows that they enhance by 9-15% (depending on the set of tasks) the task-discriminating information provided by the synergy decompositions. We suggest that the proposed methodology could be useful for assessing whether single-trial activations of one synergy depend on activations of other synergies and quantifying the effect of such dependences on the task-to-task differences in muscle activation patterns.

Blue or red? Exploring the effect of color on cognitive task performances.

PubMed

Mehta, Ravi; Zhu, Rui Juliet

2009-02-27

Existing research reports inconsistent findings with regard to the effect of color on cognitive task performances. Some research suggests that blue or green leads to better performances than red; other studies record the opposite. Current work reconciles this discrepancy. We demonstrate that red (versus blue) color induces primarily an avoidance (versus approach) motivation (study 1, n = 69) and that red enhances performance on a detail-oriented task, whereas blue enhances performance on a creative task (studies 2 and 3, n = 208 and 118). Further, we replicate these results in the domains of product design (study 4, n = 42) and persuasive message evaluation (study 5, n = 161) and show that these effects occur outside of individuals' consciousness (study 6, n = 68). We also provide process evidence suggesting that the activation of alternative motivations mediates the effect of color on cognitive task performances.

Stroop Task-Related Brain Activity in Patients With Insomnia: Changes After Cognitive-Behavioral Therapy for Insomnia.

PubMed

Hwang, Jeong Yeon; Kim, Nambeom; Kim, Soohyun; Park, Juhyun; Choi, Jae-Won; Kim, Seog Ju; Kang, Chang-Ki; Lee, Yu Jin

2018-02-16

In the present study, we compared differences in brain activity during the Stroop task between patients with chronic insomnia disorder (CID) and good sleepers (GS). Furthermore, we evaluated changes in Stroop task-related brain activity after cognitive-behavioral therapy for insomnia (CBT-I). The final analysis included 21 patients with CID and 25 GS. All participants underwent functional magnetic resonance imaging (fMRI) while performing the color-word Stroop task. CBT-I, consisting of 5 sessions, was administered to 14 patients with CID in the absence of medication. After CBT-I, fMRI was repeated in the patients with CID while performing the same task. Sleep-related questionnaires and sleep variables from a sleep diary were also obtained before and after CBT-I. No significant differences in behavioral performance in the Stroop task or task-related brain activation were observed between the CID and GS groups. No changes in behavioral performance or brain activity were found after CBT-I. However, clinical improvement in the Insomnia Severity Index (ISI) score was significantly associated with changes in the Stroop task-related regional blood oxygen level-dependent signals in the left supramarginal gyrus. Our findings suggest that cognitive impairment in patients with CID was not detectable by the Stroop task or Stroop task-related brain activation on fMRI. Moreover, there was no altered brain activity during the Stroop task after CBT-I. However, the ISI score reflected changes in the neural correlates of cognitive processes in patients with CID after CBT-I.

Extendable supervised dictionary learning for exploring diverse and concurrent brain activities in task-based fMRI.

PubMed

Zhao, Shijie; Han, Junwei; Hu, Xintao; Jiang, Xi; Lv, Jinglei; Zhang, Tuo; Zhang, Shu; Guo, Lei; Liu, Tianming

2018-06-01

Recently, a growing body of studies have demonstrated the simultaneous existence of diverse brain activities, e.g., task-evoked dominant response activities, delayed response activities and intrinsic brain activities, under specific task conditions. However, current dominant task-based functional magnetic resonance imaging (tfMRI) analysis approach, i.e., the general linear model (GLM), might have difficulty in discovering those diverse and concurrent brain responses sufficiently. This subtraction-based model-driven approach focuses on the brain activities evoked directly from the task paradigm, thus likely overlooks other possible concurrent brain activities evoked during the information processing. To deal with this problem, in this paper, we propose a novel hybrid framework, called extendable supervised dictionary learning (E-SDL), to explore diverse and concurrent brain activities under task conditions. A critical difference between E-SDL framework and previous methods is that we systematically extend the basic task paradigm regressor into meaningful regressor groups to account for possible regressor variation during the information processing procedure in the brain. Applications of the proposed framework on five independent and publicly available tfMRI datasets from human connectome project (HCP) simultaneously revealed more meaningful group-wise consistent task-evoked networks and common intrinsic connectivity networks (ICNs). These results demonstrate the advantage of the proposed framework in identifying the diversity of concurrent brain activities in tfMRI datasets.

Middle-aged human apoE4 targeted-replacement mice show retention deficits on a wide range of spatial memory tasks.

PubMed

Bour, Alexandra; Grootendorst, Jeannette; Vogel, Elise; Kelche, Christian; Dodart, Jean-Cosme; Bales, Kelly; Moreau, Pierre-Henri; Sullivan, Patrick M; Mathis, Chantal

2008-11-21

Apolipoprotein (apo) E4, one of three human apoE (h-apoE) isoforms, has been identified as a major genetic risk factor for Alzheimer's disease and for cognitive deficits associated with aging. However, the biological mechanisms involving apoE in learning and memory processes are unclear. A potential isoform-dependent role of apoE in cognitive processes was studied in human apoE targeted-replacement (TR) mice. These mice express either the human apoE3 or apoE4 gene under the control of endogenous murine apoE regulatory sequences, resulting in physiological expression of h-apoE in both a temporal and spatial pattern similar to humans. Male and female apoE3-TR, apoE4-TR, apoE-knockout and C57BL/6J mice (15-18 months) were tested with spatial memory and avoidance conditioning tasks. Compared to apoE3-TR mice, spatial memory in female apoE4-TR mice was impaired based on their poor performances in; (i) the probe test of the water-maze reference memory task, (ii) the water-maze working memory task and (iii) an active avoidance Y-maze task. Retention performance on a passive avoidance task was also impaired in apoE4-TR mice, but not in other genotypes. These deficits in both spatial and avoidance memory tasks may be related to the anatomical and functional abnormalities previously reported in the hippocampus and the amygdala of apoE4-TR mice. We conclude that the apoE4-TR mice provide an excellent model for understanding the mechanisms underlying apoE4-dependent susceptibility to cognitive decline.

How do walkers avoid a mobile robot crossing their way?

PubMed

Vassallo, Christian; Olivier, Anne-Hélène; Souères, Philippe; Crétual, Armel; Stasse, Olivier; Pettré, Julien

2017-01-01

Robots and Humans have to share the same environment more and more often. In the aim of steering robots in a safe and convenient manner among humans it is required to understand how humans interact with them. This work focuses on collision avoidance between a human and a robot during locomotion. Having in mind previous results on human obstacle avoidance, as well as the description of the main principles which guide collision avoidance strategies, we observe how humans adapt a goal-directed locomotion task when they have to interfere with a mobile robot. Our results show differences in the strategy set by humans to avoid a robot in comparison with avoiding another human. Humans prefer to give the way to the robot even when they are likely to pass first at the beginning of the interaction. Copyright © 2016 Elsevier B.V. All rights reserved.

Terbinafine is a novel and selective activator of the two-pore domain potassium channel TASK3.

PubMed

Wright, Paul D; Veale, Emma L; McCoull, David; Tickle, David C; Large, Jonathan M; Ococks, Emma; Gothard, Gemma; Kettleborough, Catherine; Mathie, Alistair; Jerman, Jeffrey

2017-11-04

Two-pore domain potassium channels (K2Ps) are characterized by their four transmembrane domain and two-pore topology. They carry background (or leak) potassium current in a variety of cell types. Despite a number of important roles there is currently a lack of pharmacological tools with which to further probe K2P function. We have developed a cell-based thallium flux assay, using baculovirus delivered TASK3 (TWIK-related acid-sensitive K + channel 3, KCNK9, K2P9.1) with the aim of identifying novel, selective TASK3 activators. After screening a library of 1000 compounds, including drug-like and FDA approved molecules, we identified Terbinafine as an activator of TASK3. In a thallium flux assay a pEC50 of 6.2 ( ±0.12) was observed. When Terbinafine was screened against TASK2, TREK2, THIK1, TWIK1 and TRESK no activation was observed in thallium flux assays. Several analogues of Terbinafine were also purchased and structure activity relationships examined. To confirm Terbinafine's activation of TASK3 whole cell patch clamp electrophysiology was carried out and clear potentiation observed in both the wild type channel and the pathophysiological, Birk-Barel syndrome associated, G236R TASK3 mutant. No activity at TASK1 was observed in electrophysiology studies. In conclusion, we have identified the first selective activator of the two-pore domain potassium channel TASK3. Copyright © 2017 Elsevier Inc. All rights reserved.

Variability in emotional responsiveness and coping style during active avoidance as a window onto psychological vulnerability to stress.

PubMed

Gorka, Adam X; LaBar, Kevin S; Hariri, Ahmad R

2016-05-01

Individual differences in coping styles are associated with psychological vulnerability to stress. Recent animal research suggests that coping styles reflect trade-offs between proactive and reactive threat responses during active avoidance paradigms, with proactive responses associated with better stress tolerance. Based on these preclinical findings, we developed a novel instructed active avoidance paradigm to characterize patterns of proactive and reactive responses using behavioral, motoric, and autonomic measures in humans. Analyses revealed significant inter-individual variability not only in the magnitude of general emotional responsiveness but also the likelihood to specifically express proactive or reactive responses. In men but not women, individual differences in general emotional responsiveness were linked to increased trait anxiety while proactive coping style was linked to increased trait aggression. These patterns are consistent with preclinical findings and suggest that instructed active avoidance paradigms may be useful in assessing psychological vulnerability to stress using objective behavioral measures. Copyright © 2016. Published by Elsevier Inc.

Heart rate variability moderates the association between attachment avoidance and self-concept reorganization following marital separation.

PubMed

Sbarra, David A; Borelli, Jessica L

2013-06-01

Despite substantial evidence indicating that relationships shape people's self-concept, relatively little is known about how people reorganize their sense of self when relationships end and whether this varies as a function of people's beliefs about relationships. In this report, we examine the prospective association between self-report adult attachment style and self-concept recovery among 89 adults following a recent marital separation. People high in attachment avoidance are characterized by the tendency to deactivate (i.e., suppress) painful attachment-related thoughts and feelings, and, following Fagundes, Diamond, and Allen (2012), we hypothesized that highly avoidant people would show better or worse self-concept outcomes depending on their ability to successfully regulate their emotional experience during a divorce-related mental recall task. We operationalized self-regulation using respiratory sinus arrhythmia (RSA) and found that highly avoidant people who showed RSA increases across our divorce-related mental activation task (DMAT) evidenced improvements in their self-concept over three months. In contrast, highly avoidant adults who showed RSA decreases during the DMAT showed no improvement (or a worsening) in their self-concept disruptions over the subsequent three months. These results suggest that RSA, an index of heart rate variability, may provide a window into self-regulation that has the potential to shed new light on why some people cope well or poorly following the loss of a relationship. Discussion centers on the potential mechanisms of action that explain why some people are able to successfully deactivate attachment-related thoughts and feelings whereas other people are not. Copyright © 2012. Published by Elsevier B.V.

Central as well as Peripheral Attentional Bottlenecks in Dual-Task Performance Activate Lateral Prefrontal Cortices

PubMed Central

Szameitat, André J.; Vanloo, Azonya; Müller, Hermann J.

2016-01-01

Human information processing suffers from severe limitations in parallel processing. In particular, when required to respond to two stimuli in rapid succession, processing bottlenecks may appear at central and peripheral stages of task processing. Importantly, it has been suggested that executive functions are needed to resolve the interference arising at such bottlenecks. The aims of the present study were to test whether central attentional limitations (i.e., bottleneck at the decisional response selection stage) as well as peripheral limitations (i.e., bottleneck at response initiation) both demand executive functions located in the lateral prefrontal cortex. For this, we re-analyzed two previous studies, in which a total of 33 participants performed a dual-task according to the paradigm of the psychological refractory period (PRP) during functional magnetic resonance imaging (fMRI). In one study (N = 17), the PRP task consisted of two two-choice response tasks known to suffer from a central bottleneck (CB group). In the other study (N = 16), the PRP task consisted of two simple-response tasks known to suffer from a peripheral bottleneck (PB group). Both groups showed considerable dual-task costs in form of slowing of the second response in the dual-task (PRP effect). Imaging results are based on the subtraction of both single-tasks from the dual-task within each group. In the CB group, the bilateral middle frontal gyri and inferior frontal gyri were activated. Higher activation in these areas was associated with lower dual-task costs. In the PB group, the right middle frontal and inferior frontal gyrus (IFG) were activated. Here, higher activation was associated with higher dual-task costs. In conclusion we suggest that central and peripheral bottlenecks both demand executive functions located in lateral prefrontal cortices (LPFC). Differences between the CB and PB groups with respect to the exact prefrontal areas activated and the correlational patterns

International Reference Ionosphere (IRI): Task Force Activity 2000

NASA Technical Reports Server (NTRS)

Bilitza, D.

2000-01-01

The annual IRI Task Force Activity was held at the Abdus Salam International Center for Theoretical Physics in Trieste, Italy from July 10 to July 14. The participants included J. Adeniyi (University of Ilorin, Nigeria), D. Bilitza (NSSDC/RITSS, USA), D. Buresova (Institute of Atmospheric Physics, Czech Republic), B. Forte (ICTP, Italy), R. Leitinger (University of Graz, Austria), B. Nava (ICTP, Italy), M. Mosert (University National Tucuman, Argentina), S. Pulinets (IZMIRAN, Russia), S. Radicella (ICTP, Italy), and B. Reinisch (University of Mass. Lowell, USA). The main topic of this Task Force Activity was the modeling of the topside ionosphere and the development of strategies for modeling of ionospheric variability. Each day during the workshop week the team debated a specific modeling problem in the morning during informal presentations and round table discussions of all participants. Ways of resolving the specific modeling problem were devised and tested in the afternoon in front of the computers of the ICTP Aeronomy and Radiopropagation Laboratory using ICTP s computer networks and internet access.

Avoiding Cancer Risk Information

PubMed Central

Emanuel, Amber S.; Kiviniemi, Marc T.; Howell, Jennifer L.; Hay, Jennifer L.; Waters, Erika A.; Orom, Heather; Shepperd, James A.

2015-01-01

RATIONALE Perceived risk for health problems such as cancer is a central construct in many models of health decision making and a target for behavior change interventions. However, some portion of the population actively avoids cancer risk information. The prevalence of, explanations for, and consequences of such avoidance are not well understood. OBJECTIVE We examined the prevalence and demographic and psychosocial correlates of cancer risk information avoidance preference in a nationally representative sample. We also examined whether avoidance of cancer risk information corresponds with avoidance of cancer screening. RESULTS Based on our representative sample, 39% of the population indicated that they agreed or strongly agreed that they would “rather not know [their] chance of getting cancer.” This preference was stronger among older participants, female participants, and participants with lower levels of education. Preferring to avoid cancer risk information was stronger among participants who agreed with the beliefs that everything causes cancer, that there’s not much one can do to prevent cancer, and that there are too many recommendations to follow. Finally, the preference to avoid cancer risk information was associated with lower levels of screening for colon cancer. CONCLUSION These findings suggest that cancer risk information avoidance is a multi-determined phenomenon that is associated with demographic characteristics and psychosocial individual differences and also relates to engagement in cancer screening. PMID:26560410

Does practicing a wide range of joint angle configurations lead to higher flexibility in a manual obstacle-avoidance target-pointing task?

PubMed Central

Bootsma, Reinoud J.; Schoemaker, Marina M.; Otten, Egbert; Mouton, Leonora J.; Bongers, Raoul M.

2017-01-01

Flexibility in motor actions can be defined as variability in the use of degrees of freedom (e.g., joint angles in the arm) over repetitions while keeping performance (e.g., fingertip position) stabilized. We examined whether flexibility can be increased through enlarging the joint angle range during practice in a manual obstacle-avoidance target-pointing task. To establish differences in flexibility we partitioned the variability in joint angles over repetitions in variability within (GEV) and variability outside the solution space (NGEV). More GEV than NGEV reflects flexibility; when the ratio of the GEV and NGEV is higher, flexibility is higher. The pretest and posttest consisted of 30 repetitions of manual pointing to a target while moving over a 10 cm high obstacle. To enlarge the joint angle range during practice participants performed 600 target-pointing movements while moving over obstacles of different heights (5–9 cm, 11–15 cm). The results indicated that practicing movements over obstacles of different heights led participants to use enlarged range of joint angles compared to the range of joint angles used in movements over the 10 cm obstacle in the pretest. However, for each individual obstacle neither joint angle variance nor flexibility were higher during practice. We also did not find more flexibility after practice. In the posttest, joint angle variance was in fact smaller than before practice, primarily in GEV. The potential influences of learning effects and the task used that could underlie the results obtained are discussed. We conclude that with this specific type of practice in this specific task, enlarging the range of joint angles does not lead to more flexibility. PMID:28700695

Extinction of avoidance behavior by safety learning depends on endocannabinoid signaling in the hippocampus.

PubMed

Micale, Vincenzo; Stepan, Jens; Jurik, Angela; Pamplona, Fabricio A; Marsch, Rudolph; Drago, Filippo; Eder, Matthias; Wotjak, Carsten T

2017-07-01

The development of exaggerated avoidance behavior is largely responsible for the decreased quality of life in patients suffering from anxiety disorders. Studies using animal models have contributed to the understanding of the neural mechanisms underlying the acquisition of avoidance responses. However, much less is known about its extinction. Here we provide evidence in mice that learning about the safety of an environment (i.e., safety learning) rather than repeated execution of the avoided response in absence of negative consequences (i.e., response extinction) allowed the animals to overcome their avoidance behavior in a step-down avoidance task. This process was context-dependent and could be blocked by pharmacological (3 mg/kg, s.c.; SR141716) or genetic (lack of cannabinoid CB1 receptors in neurons expressing dopamine D1 receptors) inactivation of CB1 receptors. In turn, the endocannabinoid reuptake inhibitor AM404 (3 mg/kg, i.p.) facilitated safety learning in a CB1-dependent manner and attenuated the relapse of avoidance behavior 28 days after conditioning. Safety learning crucially depended on endocannabinoid signaling at level of the hippocampus, since intrahippocampal SR141716 treatment impaired, whereas AM404 facilitated safety learning. Other than AM404, treatment with diazepam (1 mg/kg, i.p.) impaired safety learning. Drug effects on behavior were directly mirrored by drug effects on evoked activity propagation through the hippocampal trisynaptic circuit in brain slices: As revealed by voltage-sensitive dye imaging, diazepam impaired whereas AM404 facilitated activity propagation to CA1 in a CB1-dependent manner. In line with this, systemic AM404 enhanced safety learning-induced expression of Egr1 at level of CA1. Together, our data render it likely that AM404 promotes safety learning by enhancing information flow through the trisynaptic circuit to CA1. Copyright © 2017 Elsevier Ltd. All rights reserved.

Phasic dopamine release in the rat nucleus accumbens predicts approach and avoidance performance

PubMed Central

Gentry, Ronny N.; Lee, Brian; Roesch, Matthew R.

2016-01-01

Dopamine (DA) is critical for reward processing, but significantly less is known about its role in punishment avoidance. Using a combined approach-avoidance task, we measured phasic DA release in the nucleus accumbens (NAc) of rats during presentation of cues that predicted reward, punishment or neutral outcomes and investigated individual differences based on avoidance performance. Here we show that DA release within a single microenvironment is higher for reward and avoidance cues compared with neutral cues and positively correlated with poor avoidance behaviour. We found that DA release delineates trial-type during sessions with good avoidance but is non-selective during poor avoidance, with high release correlating with poor performance. These data demonstrate that phasic DA is released during cued approach and avoidance within the same microenvironment and abnormal processing of value signals is correlated with poor performance. PMID:27786172

Task Performance and Meta-Cognitive Outcomes When Using Activity Workstations and Traditional Desks

PubMed Central

Pilcher, June J.; Baker, Victoria C.

2016-01-01

The purpose of the current study is to compare the effects of light physical activity to sedentary behavior on cognitive task performance and meta-cognitive responses. Thirty-eight undergraduate students participated in the study. The participants used a stationary bicycle with a desk top and a traditional desk while completing two complex cognitive tasks and measures of affect, motivation, morale, and engagement. The participants pedaled the stationary bicycle at a slow pace (similar in exertion to a normal walking pace) while working. The results indicated that cognitive task performance did not change between the two workstations. However, positive affect, motivation, and morale improved when using the stationary bicycle. These results suggest that activity workstations could be implemented in the work place and in educational settings to help decrease sedentary behavior without negatively affecting performance. Furthermore, individuals could experience a positive emotional response when working on activity workstations which in turn could help encourage individuals to choose to be more physical active during daily activities. PMID:27445921

Methodology for Determining the Avoidable and Fully Allocated Costs of Amtrak Routes : Volume II, Appendix A

DOT National Transportation Integrated Search

2009-08-01

The Federal Railroad Administration tasked the Volpe Center with developing a methodology for determining the avoidable and fully allocated costs of Amtrak routes. Avoidable costs are costs that would not be incurred if an Amtrak route were discontin...

Methodology for determining the avoidable and fully allocated costs of Amtrak routes, volume 1 : main report

DOT National Transportation Integrated Search

2009-08-01

The Federal Railroad Administration tasked the Volpe Center with developing a methodology for determining the avoidable and fully allocated costs of Amtrak routes. Avoidable costs are costs that would not be incurred if an Amtrak route were discontin...

Task activation and functional connectivity show concordant memory laterality in temporal lobe epilepsy.

PubMed

Sideman, Noah; Chaitanya, Ganne; He, Xiaosong; Doucet, Gaelle; Kim, Na Young; Sperling, Michael R; Sharan, Ashwini D; Tracy, Joseph I

2018-04-01

In epilepsy, asymmetries in the organization of mesial temporal lobe (MTL) functions help determine the cognitive risk associated with procedures such as anterior temporal lobectomy. Past studies have investigated the change/shift in a visual episodic memory laterality index (LI) in mesial temporal lobe structures through functional magnetic resonance imaging (fMRI) task activations. Here, we examine whether underlying task-related functional connectivity (FC) is concordant with such standard fMRI laterality measures. A total of 56 patients with temporal lobe epilepsy (TLE) (Left TLE [LTLE]: 31; Right TLE [RTLE]: 25) and 34 matched healthy controls (HC) underwent fMRI scanning during performance of a scene encoding task (SET). We assessed an activation-based LI of the hippocampal gyrus (HG) and parahippocampal gyrus (PHG) during the SET and its correspondence with task-related FC measures. Analyses involving the HG and PHG showed that the patients with LTLE had a consistently higher LI (right-lateralized) than that of the HC and group with RTLE, indicating functional reorganization. The patients with RTLE did not display a reliable contralateral shift away from the pathology, with the mesial structures showing quite distinct laterality patterns (HG, no laterality bias; PHG, no evidence of LI shift). The FC data for the group with LTLE provided confirmation of reorganization effects, revealing that a rightward task LI may be based on underlying connections between several left-sided regions (middle/superior occipital and left medial frontal gyri) and the right PHG. The FCs between the right HG and left anterior cingulate/medial frontal gyri were also observed in LTLE. Importantly, the data demonstrate that the areas involved in the LTLE task activation shift to the right hemisphere showed a corresponding increase in task-related FCs between the hemispheres. Altered laterality patterns based on mesial temporal lobe epilepsy (MTLE) pathology manifest as several

fMRI activation patterns in an analytic reasoning task: consistency with EEG source localization

NASA Astrophysics Data System (ADS)

Li, Bian; Vasanta, Kalyana C.; O'Boyle, Michael; Baker, Mary C.; Nutter, Brian; Mitra, Sunanda

2010-03-01

Functional magnetic resonance imaging (fMRI) is used to model brain activation patterns associated with various perceptual and cognitive processes as reflected by the hemodynamic (BOLD) response. While many sensory and motor tasks are associated with relatively simple activation patterns in localized regions, higher-order cognitive tasks may produce activity in many different brain areas involving complex neural circuitry. We applied a recently proposed probabilistic independent component analysis technique (PICA) to determine the true dimensionality of the fMRI data and used EEG localization to identify the common activated patterns (mapped as Brodmann areas) associated with a complex cognitive task like analytic reasoning. Our preliminary study suggests that a hybrid GLM/PICA analysis may reveal additional regions of activation (beyond simple GLM) that are consistent with electroencephalography (EEG) source localization patterns.

Somatic Arc protein expression in hippocampal granule cells is increased in response to environmental change but independent of task-specific learning.

PubMed

Cleland, J P; Willis, E F; Bartlett, P F; Vukovic, J

2017-09-29

Activated neurons express immediate-early genes, such as Arc. Expression of Arc in the hippocampal granule cell layer, an area crucial for spatial learning and memory, is increased during acquisition of spatial learning; however, it is unclear whether this effect is related to the task-specific learning process or to nonspecific aspects of the testing procedure (e.g. exposure to the testing apparatus and exploration of the environment). Herein, we show that Arc-positive cells numbers are increased to the same extent in the granule cell layer after both acquisition of a single spatial learning event in the active place avoidance task and exploration of the testing environment, as compared to naïve (i.e. caged) mice. Repeated exposure the testing apparatus and environment did not reduce Arc expression. Furthermore, Arc expression did not correlate with performance in both adult and aged animals, suggesting that exploration of the testing environment, rather than the specific acquisition of the active place avoidance task, induces Arc expression in the dentate granule cell layer. These findings thus suggest that Arc is an experience-induced immediate-early gene.

The influence of approach-avoidance motivational orientation on conflict adaptation.

PubMed

Hengstler, Maikel; Holland, Rob W; van Steenbergen, Henk; van Knippenberg, Ad

2014-06-01

To deal effectively with a continuously changing environment, our cognitive system adaptively regulates resource allocation. Earlier findings showed that an avoidance orientation (induced by arm extension), relative to an approach orientation (induced by arm flexion), enhanced sustained cognitive control. In avoidance conditions, performance on a cognitive control task was enhanced, as indicated by a reduced congruency effect, relative to approach conditions. Extending these findings, in the present behavioral studies we investigated dynamic adaptations in cognitive control-that is, conflict adaptation. We proposed that an avoidance state recruits more resources in response to conflicting signals, and thereby increases conflict adaptation. Conversely, in an approach state, conflict processing diminishes, which consequently weakens conflict adaptation. As predicted, approach versus avoidance arm movements affected both behavioral congruency effects and conflict adaptation: As compared to approach, avoidance movements elicited reduced congruency effects and increased conflict adaptation. These results are discussed in line with a possible underlying neuropsychological model.

Fall-related activity avoidance in relation to a history of falls or near falls, fear of falling and disease severity in people with Parkinson's disease.

PubMed

Kader, Manzur; Iwarsson, Susanne; Odin, Per; Nilsson, Maria H

2016-06-02

There is limited knowledge concerning fall-related activity avoidance in people with Parkinson's disease (PD); such knowledge would be of importance for the development of more efficient PD-care and rehabilitation. This study aimed to examine how fall-related activity avoidance relates to a history of self-reported falls/near falls and fear of falling (FOF) as well as to disease severity in people with PD. Data were collected from 251 (61 % men) participants with PD; their median (min-max) age and PD duration were 70 (45-93) and 8 (1-43) years, respectively. A self-administered postal survey preceded a home visit which included observations, clinical tests and interview-administered questionnaires. Fall-related activity avoidance was assessed using the modified Survey of Activities and Fear of Falling in the Elderly (mSAFFE) as well as by using a dichotomous (Yes/No) question. Further dichotomous questions concerned: the presence of FOF and the history (past 6 months) of falls or near falls, followed by stating the number of incidents. Disease severity was assessed according to the Hoehn and Yahr (HY) stages. In the total sample (n = 251), 41 % of the participants reported fall-related activity avoidance; the median mSAFFE score was 22. In relation to a history of fall, the proportions of participants (p < 0.001) that reported fall-related activity avoidance were: non-fallers (30 %), single fallers (50 %) and recurrent fallers, i.e. ≥ 2 falls (57 %). Among those that reported near falls (but no falls), 51 % (26 out of 51) reported fall-related activity avoidance. Of those that reported FOF, 70 % reported fall-related activity avoidance. Fall-related activity avoidance ranged from 24 % in the early PD-stage (HY I) to 74 % in the most severe stages (HY IV-V). Results indicate that fall-related activity avoidance may be related to a history of self-reported falls/near falls, FOF and disease severity in people with PD. Importantly, fall

Active avoidance: escape and dodging behaviors for reactive control

NASA Astrophysics Data System (ADS)

Arkin, Ronald C.; Carter, William M.

1992-03-01

New methods for producing avoidance behavior among moving obstacles within the context of reactive robotic control are described. These specifically include escape and dodging behaviors. Dodging is concerned with the avoidance of a ballistic projectile while escape is more useful within the context of chase. The motivation and formulation of these new reactive behaviors are presented. Simulation results of a robot in a cluttered and moving world are also provided.

Run-Off-Road Collision Avoidance Countermeasures Using IVHS Countermeasures: Task 3, Volume 1

DOT National Transportation Integrated Search

1995-08-23

The Run-Off-Road Collision Avoidance Using IVHS Countermeasures program is to address the single vehicle crash problem through application of technology to prevent and/or reduce the severity oi these crashes. This report describes the findings of the...

Run-Off-Road Collision Avoidance Countermeasures Using IVHS Countermeasures Task 3 - Volume 2

DOT National Transportation Integrated Search

1995-08-23

The Run-Off-Road Collision Avoidance Using IVHS Countermeasures program is to address the single vehicle crash problem through application of technology to prevent and/or reduce the severity of these crashes. : This report describes the findings of t...

Effect of visual feedback on brain activation during motor tasks: an FMRI study.

PubMed

Noble, Jeremy W; Eng, Janice J; Boyd, Lara A

2013-07-01

This study examined the effect of visual feedback and force level on the neural mechanisms responsible for the performance of a motor task. We used a voxel-wise fMRI approach to determine the effect of visual feedback (with and without) during a grip force task at 35% and 70% of maximum voluntary contraction. Two areas (contralateral rostral premotor cortex and putamen) displayed an interaction between force and feedback conditions. When the main effect of feedback condition was analyzed, higher activation when visual feedback was available was found in 22 of the 24 active brain areas, while the two other regions (contralateral lingual gyrus and ipsilateral precuneus) showed greater levels of activity when no visual feedback was available. The results suggest that there is a potentially confounding influence of visual feedback on brain activation during a motor task, and for some regions, this is dependent on the level of force applied.

Cognitive Activities in Solving Mathematical Tasks: The Role of a Cognitive Obstacle

ERIC Educational Resources Information Center

Antonijevic, Radovan

2016-01-01

In the process of learning mathematics, students practice various forms of thinking activities aimed to substantially contribute to the development of their different cognitive structures. In this paper, the subject matter is a "cognitive obstacle", a phenomenon that occurs in the procedures of solving mathematical tasks. Each task in…

Methylphenidate and brain activity in a reward/conflict paradigm: role of the insula in task performance.

PubMed

Ivanov, Iliyan; Liu, Xun; Clerkin, Suzanne; Schulz, Kurt; Fan, Jin; Friston, Karl; London, Edythe D; Schwartz, Jeffrey; Newcorn, Jeffrey H

2014-06-01

Psychostimulants, such as methylphenidate, are thought to improve information processing in motivation-reward and attention-activation networks by enhancing the effects of more relevant signals and suppressing those of less relevant ones; however the nature of such reciprocal influences remains poorly understood. To explore this question, we tested the effect of methylphenidate on performance and associated brain activity in the Anticipation, Conflict, Reward (ACR) task. Sixteen healthy adult volunteers, ages 21-45, were scanned twice using functional magnetic resonance imaging (fMRI) as they performed the ACR task under placebo and methylphenidate conditions. A three-way repeated measures analysis of variance, with cue (reward vs. non-reward), target (congruent vs. incongruent) and medication condition (methylphenidate vs. placebo) as the factors, was used to analyze behaviors on the task. Blood oxygen level dependent (BOLD) signals, reflecting task-related neural activity, were evaluated using linear contrasts. Participants exhibited significantly greater accuracy in the methylphenidate condition than the placebo condition. Compared with placebo, the methylphenidate condition also was associated with lesser task-related activity in components of attention-activation systems irrespective of the reward cue, and less task-related activity in components of the reward-motivation system, particularly the insula, during reward trials irrespective of target difficulty. These results suggest that methylphenidate enhances task performance by improving efficiency of information processing in both reward-motivation and in attention-activation systems. Published by Elsevier B.V.

All for one but not one for all: how multiple number representations are recruited in one numerical task.

PubMed

Wood, Guilherme; Nuerk, Hans-Christoph; Moeller, Korbinian; Geppert, Barbara; Schnitker, Ralph; Weber, Jochen; Willmes, Klaus

2008-01-02

Number processing recruits a complex network of multiple numerical representations. Usually the components of this network are examined in a between-task approach with the disadvantage of relying upon different instructions, tasks, and inhomogeneous stimulus sets across different studies. A within-task approach may avoid these disadvantages and access involved numerical representations more specifically. In the present study we employed a within-task approach to investigate numerical representations activated in the number bisection task (NBT) using parametric rapid event-related fMRI. Participants were to judge whether the central number of a triplet was also its arithmetic mean (e.g. 23_26_29) or not (e.g. 23_25_29). Activation in the left inferior parietal cortex was associated with the deployment of arithmetic fact knowledge, while activation of the intraparietal cortex indicated more intense magnitude processing, instrumental aspects of calculation and integration of the base-10 structure of two-digit numbers. These results replicate evidence from the literature. Furthermore, activation in the dorsolateral and ventrolateral prefrontal cortex revealed mechanisms of feature monitoring and inhibition as well as allocation of cognitive resources recruited to solve a specific triplet. We conclude that the network of numerical representations should rather be studied in a within-task approach than in varying between-task approaches.

Brain activation and deactivation during location and color working memory tasks in 11-13-year-old children.

PubMed

Vuontela, Virve; Steenari, Maija-Riikka; Aronen, Eeva T; Korvenoja, Antti; Aronen, Hannu J; Carlson, Synnöve

2009-02-01

Using functional magnetic resonance imaging (fMRI) and n-back tasks we investigated whether, in 11-13-year-old children, spatial (location) and nonspatial (color) information is differentially processed during visual attention (0-back) and working memory (WM) (2-back) tasks and whether such cognitive task performance, compared to a resting state, results in regional deactivation. The location 0-back task, compared to the color 0-back task, activated segregated areas in the frontal, parietal and occipital cortices whereas no differentially activated voxels were obtained when location and color 2-back tasks were directly contrasted. Several midline cortical areas were less active during 0- and 2-back task performance than resting state. The task-induced deactivation increased with task difficulty as demonstrated by larger deactivation during 2-back than 0-back tasks. The results suggest that, in 11-13-year-old children, the visual attentional network is differently recruited by spatial and nonspatial information processing, but the functional organization of cortical activation in WM in this age group is not based on the type of information processed. Furthermore, 11-13-year-old children exhibited a similar pattern of cortical deactivation that has been reported in adults during cognitive task performance compared to a resting state.

Accident Avoidance Skill Training and Performance Testing. Final Report.

ERIC Educational Resources Information Center

Hatterick, G. Richard; Barthurst, James R.

A two-phased study was conducted to determine the feasibility of training drivers to acquire skills needed to avoid critical conflict motor vehicle accidents, and to develop the procedures and materials necessary for such training. Basic data were derived from indepth accident investigations and task analyses of driver behavior. Principal…

A Quantitative Relationship between Signal Detection in Attention and Approach/Avoidance Behavior

PubMed Central

Viswanathan, Vijay; Sheppard, John P.; Kim, Byoung W.; Plantz, Christopher L.; Ying, Hao; Lee, Myung J.; Raman, Kalyan; Mulhern, Frank J.; Block, Martin P.; Calder, Bobby; Lee, Sang; Mortensen, Dale T.; Blood, Anne J.; Breiter, Hans C.

2017-01-01

This study examines how the domains of reward and attention, which are often studied as independent processes, in fact interact at a systems level. We operationalize divided attention with a continuous performance task and variables from signal detection theory (SDT), and reward/aversion with a keypress task measuring approach/avoidance in the framework of relative preference theory (RPT). Independent experiments with the same subjects showed a significant association between one SDT and two RPT variables, visualized as a three-dimensional structure. Holding one of these three variables constant, further showed a significant relationship between a loss aversion-like metric from the approach/avoidance task, and the response bias observed during the divided attention task. These results indicate that a more liberal response bias under signal detection (i.e., a higher tolerance for noise, resulting in a greater proportion of false alarms) is associated with higher “loss aversion.” Furthermore, our functional model suggests a mechanism for processing constraints with divided attention and reward/aversion. Together, our results argue for a systematic relationship between divided attention and reward/aversion processing in humans. PMID:28270776

Post-traumatic stress avoidance is attenuated by corticosterone and associated with brain levels of steroid receptor co-activator-1 in rats.

PubMed

Whitaker, Annie M; Farooq, Muhammad A; Edwards, Scott; Gilpin, Nicholas W

2016-01-01

Individuals with post-traumatic stress disorder (PTSD) avoid trauma-related stimuli and exhibit blunted hypothalamic-pituitary-adrenal (HPA) axis activation at the time of stress. Our rodent model of stress mimics the avoidance symptom cluster of PTSD. Rats are classified as "Avoiders" or "Non-Avoiders" post-stress based on the avoidance of a predator-odor paired context. Previously, we found Avoiders exhibit an attenuated HPA stress response to predator odor. We hypothesized that corticosterone administration before stress would reduce the magnitude and incidence of stress-paired context avoidance. Furthermore, we also predicted that Avoiders would exhibit altered expression of glucocorticoid receptor (GR) signaling machinery elements, including steroid receptor co-activator (SRC)-1. Male Wistar rats (n = 16) were pretreated with corticosterone (25 mg/kg) or saline and exposed to predator-odor stress paired with a context and tested for avoidance 24 h later. A second group of corticosterone-naïve rats (n = 24) were stressed (or not), indexed for avoidance 24 h later, and killed 48 h post-odor exposure to measure phosphorylated GR, FKBP51 and SRC-1 levels in the paraventricular nucleus (PVN), central amygdala (CeA) and ventral hippocampus (VH), all brain sites that highly express GRs and regulate HPA function. Corticosterone pretreatment reduced the magnitude and incidence of avoidance. In Avoiders, predator-odor exposure led to lower SRC-1 expression in the PVN and CeA, and higher SRC-1 expression in the VH. SRC-1 expression in PVN, CeA and VH was predicted by prior avoidance behavior. Hence, a blunted HPA stress response may contribute to stress-induced neuroadaptations in central SRC-1 levels and behavioral dysfunction in Avoider rats.

Approach/avoidance in dreams.

PubMed

Malcolm-Smith, Susan; Koopowitz, Sheri; Pantelis, Eleni; Solms, Mark

2012-03-01

The influential threat simulation theory (TST) asserts that dreaming yields adaptive advantage by providing a virtual environment in which threat-avoidance may be safely rehearsed. We have previously found the incidence of biologically threatening dreams to be around 20%, with successful threat avoidance occurring in approximately one-fifth of such dreams. TST asserts that threat avoidance is over-represented relative to other possible dream contents. To begin assessing this issue, we contrasted the incidence of 'avoidance' dreams with that of their opposite: 'approach' dreams. Because TST states that the threat-avoidance function is only fully activated in ecologically valid (biologically threatening) contexts, we also performed this contrast for populations living in both high- and low-threat environments. We find that 'approach' dreams are significantly more prevalent across both contexts. We suggest these results are more consistent with the view that dreaming is generated by reward-seeking systems than by fear-conditioning systems, although reward-seeking is clearly not the only factor determining the content of dreams. Copyright © 2011 Elsevier Inc. All rights reserved.

Contrasting effects of acute and chronic treatment with imipramine and fluoxetine on inhibitory avoidance and escape responses in mice exposed to the elevated T-maze.

PubMed

Gomes, Karina Santos; de Carvalho-Netto, Eduardo Ferreira; Monte, Kátia Cristina Da Silva; Acco, Bruno; Nogueira, Paulo José de Campos; Nunes-de-Souza, Ricardo Luiz

2009-03-30

The elevated T-maze (ETM) is an animal model of anxiety-like behavior that assesses two different defensive behavioral tasks in the same animal-acquisition of inhibitory avoidance and latency to escape from an open and elevated arm. In rats, cute and chronic treatments with anxiolytic-like drugs impair avoidance acquisition while only chronic administration of panicolytic-like drugs impairs open arm withdrawal. To date, only the acute effects of anxiolytic/anxiogenic or panicolytic/panicogenic drugs have been tested in the mouse ETM and the results have partially corroborated those found in the rat ETM. This study investigated the effects of acute (a single intraperitoneal injection 30 min before testing) and chronic (daily i.p. injections for 15 consecutive days) treatment with imipramine or fluoxetine, non-selective and selective serotonin reuptake inhibitors, respectively, on inhibitory avoidance and escape tasks in the mouse ETM. Neither acute nor chronic treatment with imipramine (0, 1, 5 or 10 mg/kg, i.p.) significantly changed the behavioral profile of mice in the two ETM tasks. Interestingly, while acute fluoxetine (0, 5, 10, 20 or 40 mg/kg, i.p.) facilitated inhibitory avoidance and impaired escape latency, chronic treatment (0, 5, 20 or 40 mg/kg, i.p.) with this selective serotonin reuptake inhibitor (SSRI) produced an opposite effect, i.e., it impaired inhibitory avoidance acquisition and facilitated open arm withdrawal. Importantly, acute or chronic treatment with imipramine (except at the highest dose that increased locomotion when given acutely) or fluoxetine failed to alter general locomotor activity in mice as assessed in an ETM in which all arms were enclosed by lateral walls (eETM). These results suggest that inhibitory avoidance acquisition is a useful task for the evaluation of acute and chronic effects of SSRI treatment on anxiety in mice. However, as open arm latency was actually increased and reduced by acute and chronic fluoxetine

Mice learn to avoid regret.

PubMed

Sweis, Brian M; Thomas, Mark J; Redish, A David

2018-06-01

Regret can be defined as the subjective experience of recognizing that one has made a mistake and that a better alternative could have been selected. The experience of regret is thought to carry negative utility. This typically takes two distinct forms: augmenting immediate postregret valuations to make up for losses, and augmenting long-term changes in decision-making strategies to avoid future instances of regret altogether. While the short-term changes in valuation have been studied in human psychology, economics, neuroscience, and even recently in nonhuman-primate and rodent neurophysiology, the latter long-term process has received far less attention, with no reports of regret avoidance in nonhuman decision-making paradigms. We trained 31 mice in a novel variant of the Restaurant Row economic decision-making task, in which mice make decisions of whether to spend time from a limited budget to achieve food rewards of varying costs (delays). Importantly, we tested mice longitudinally for 70 consecutive days, during which the task provided their only source of food. Thus, decision strategies were interdependent across both trials and days. We separated principal commitment decisions from secondary reevaluation decisions across space and time and found evidence for regret-like behaviors following change-of-mind decisions that corrected prior economically disadvantageous choices. Immediately following change-of-mind events, subsequent decisions appeared to make up for lost effort by altering willingness to wait, decision speed, and pellet consumption speed, consistent with past reports of regret in rodents. As mice were exposed to an increasingly reward-scarce environment, we found they adapted and refined distinct economic decision-making strategies over the course of weeks to maximize reinforcement rate. However, we also found that even without changes in reinforcement rate, mice transitioned from an early strategy rooted in foraging to a strategy rooted in

Ventrolateral prefrontal activation during a N-back task assessed with multichannel functional near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Zhou, Yuan; Zhu, Ye; Jiang, Tianzi

2007-05-01

Functional near-infrared spectroscopy (fNIRS) has been used to investigate the changes in the concentration of oxygenated (O2Hb) and deoxygenated (HHb) hemoglobin in brain issue during several cognitive tasks. In the present study, by means of multichannel dual wavelength light-emitting diode continuous-wave (CW) NIRS, we investigated the blood oxygenation changes of prefrontal cortex in 18 healthy subjects while performing a verbal n-back task (0-back and 2-back), which has been rarely investigated by fNIRS. Compared to the 0-back task (control task), we found a significant increase of O2Hb and total amount of hemoglobin (THb) in left and right ventrolateral prefrontal cortex (VLPFC) during the execution of the 2-back task compared to the 0-back task (p<0.05, FDR corrected). This result is consistent with the previous functional neuroimaging studies that have found the VLPFC activation related to verbal working memory. However, we found no significant hemisphere dominance. In addition, the effects of gender and its interaction with task performance on O2Hb concentration change were suggested in the present study. Our findings not only confirm that multichannel fNIRS is suitable to detect spatially specific activation during the performance of cognitive tasks; but also suggest that it should be cautious of gender-dependent difference in cerebral activation when interpreting the fNIRS data during cognitive tasks.

Analysis of proximal and distal muscle activity during handwriting tasks.

PubMed

Naider-Steinhart, Shoshana; Katz-Leurer, Michal

2007-01-01

In this study we sought to describe upper-extremity proximal and distal muscle activity in typically developing children during a handwriting task and to explore the relationship between muscle activity and speed and quality of writing. We evaluated 35 third- and fourth-grade Israeli children using the Alef-Alef Ktav Yad Hebrew Handwriting Test. Simultaneously, we recorded the participants' upper trapezius and thumb muscle activity by surface electromyography. Using the coefficient of variation (standard deviation divided by mean amplitude) as a measure of variability within each muscle, we analyzed differences in muscle activity variability within and between muscles. The proximal muscle displayed significantly less variability than the distal muscles. Decreased variability in proximal muscle activity was associated with decreased variability in distal muscle activity, and decreased variability in the distal muscles was significantly associated with faster speed of writing. The lower amount of variability exhibited in the proximal muscle compared with the distal muscles seems to indicate that the proximal muscle functions as a stabilizer during a handwriting task. In addition, decreased variability in both proximal and distal muscle activity appears to be more economical and is related to faster writing speed. Knowledge of the type of proximal and distal muscle activity used during handwriting can help occupational therapists plan treatment for children with handwriting disabilities.

Radar-based collision avoidance for unmanned surface vehicles

NASA Astrophysics Data System (ADS)

Zhuang, Jia-yuan; Zhang, Lei; Zhao, Shi-qi; Cao, Jian; Wang, Bo; Sun, Han-bing

2016-12-01

Unmanned surface vehicles (USVs) have become a focus of research because of their extensive applications. To ensure safety and reliability and to perform complex tasks autonomously, USVs are required to possess accurate perception of the environment and effective collision avoidance capabilities. To achieve these, investigation into realtime marine radar target detection and autonomous collision avoidance technologies is required, aiming at solving the problems of noise jamming, uneven brightness, target loss, and blind areas in marine radar images. These technologies should also satisfy the requirements of real-time and reliability related to high navigation speeds of USVs. Therefore, this study developed an embedded collision avoidance system based on the marine radar, investigated a highly real-time target detection method which contains adaptive smoothing algorithm and robust segmentation algorithm, developed a stable and reliable dynamic local environment model to ensure the safety of USV navigation, and constructed a collision avoidance algorithm based on velocity obstacle (V-obstacle) which adjusts the USV's heading and speed in real-time. Sea trials results in multi-obstacle avoidance firstly demonstrate the effectiveness and efficiency of the proposed avoidance system, and then verify its great adaptability and relative stability when a USV sailing in a real and complex marine environment. The obtained results will improve the intelligent level of USV and guarantee the safety of USV independent sailing.

Acquisition and extinction of human avoidance behavior: attenuating effect of safety signals and associations with anxiety vulnerabilities.

PubMed

Sheynin, Jony; Beck, Kevin D; Servatius, Richard J; Myers, Catherine E

2014-01-01

While avoidance behavior is often an adaptive strategy, exaggerated avoidance can be detrimental and result in the development of psychopathologies, such as anxiety disorders. A large animal literature shows that the acquisition and extinction of avoidance behavior in rodents depends on individual differences (e.g., sex, strain) and might be modulated by the presence of environmental cues. However, there is a dearth of such reports in human literature, mainly due to the lack of adequate experimental paradigms. In the current study, we employed a computer-based task, where participants control a spaceship and attempt to gain points by shooting an enemy spaceship that appears on the screen. Warning signals predict on-screen aversive events; the participants can learn a protective response to escape or avoid these events. This task has been recently used to reveal facilitated acquisition of avoidance behavior in individuals with anxiety vulnerability due to female sex or inhibited personality. Here, we extended the task to include an extinction phase, and tested the effect of signals that appeared during "safe" periods. Healthy young adults (n = 122) were randomly assigned to a testing condition with or without such signals. Results showed that the addition of safety signals during the acquisition phase impaired acquisition (in females) and facilitated extinction of the avoidance behavior. We also replicated our recent finding of an association between female sex and longer avoidance duration and further showed that females continued to demonstrate more avoidance behavior even on extinction trials when the aversive events no longer occurred. This study is the first to show sex differences on the acquisition and extinction of human avoidance behavior and to demonstrate the role of safety signals in such behavior, highlighting the potential relevance of safety signals for cognitive therapies that focus on extinction learning to treat anxiety symptoms.

Acquisition and Extinction of Human Avoidance Behavior: Attenuating Effect of Safety Signals and Associations with Anxiety Vulnerabilities

PubMed Central

Sheynin, Jony; Beck, Kevin D.; Servatius, Richard J.; Myers, Catherine E.

2014-01-01

While avoidance behavior is often an adaptive strategy, exaggerated avoidance can be detrimental and result in the development of psychopathologies, such as anxiety disorders. A large animal literature shows that the acquisition and extinction of avoidance behavior in rodents depends on individual differences (e.g., sex, strain) and might be modulated by the presence of environmental cues. However, there is a dearth of such reports in human literature, mainly due to the lack of adequate experimental paradigms. In the current study, we employed a computer-based task, where participants control a spaceship and attempt to gain points by shooting an enemy spaceship that appears on the screen. Warning signals predict on-screen aversive events; the participants can learn a protective response to escape or avoid these events. This task has been recently used to reveal facilitated acquisition of avoidance behavior in individuals with anxiety vulnerability due to female sex or inhibited personality. Here, we extended the task to include an extinction phase, and tested the effect of signals that appeared during “safe” periods. Healthy young adults (n = 122) were randomly assigned to a testing condition with or without such signals. Results showed that the addition of safety signals during the acquisition phase impaired acquisition (in females) and facilitated extinction of the avoidance behavior. We also replicated our recent finding of an association between female sex and longer avoidance duration and further showed that females continued to demonstrate more avoidance behavior even on extinction trials when the aversive events no longer occurred. This study is the first to show sex differences on the acquisition and extinction of human avoidance behavior and to demonstrate the role of safety signals in such behavior, highlighting the potential relevance of safety signals for cognitive therapies that focus on extinction learning to treat anxiety symptoms. PMID

Inhibition of memory consolidation after active avoidance conditioning by antisense intervention with ependymin gene expression.

PubMed

Schmidt, R; Brysch, W; Rother, S; Schlingensiepen, K H

1995-10-01

A rapid increase in ependymin mRNA expression demonstrated by semiquantitative in situ hybridization after avoidance conditioning on goldfish suggested a molecular demand for newly synthesized ependymin translation product. To inhibit de novo synthesis of ependymin molecules without interference with preexisting ones, 18 mer anti-ependymin mRNA-phosphorothioate oligodeoxynucleotides (S-ODNs) were injected into the perimeningeal brain fluid before active avoidance training. S-ODN-injected animals learned the avoidance response; however, they were amnesic in the test. When injected into overtrained animals, S-ODNs did not interfere with retrieval or performance of the avoidance response. Fish treated with randomized S-ODN sequences served as further controls. Incorporation of S-ODNs was analyzed by injection of fluorescein isothiocyanate (FITC)-conjugated oligodeoxynucleotide probes. Microscopic observation revealed strong FITC-S-ODN fluorescence in reticular-shaped fibroblasts, the only known site of ependymin synthesis. Results demonstrate that selective inhibition of ependymin gene expression in vivo can specifically prevent memory formation. We conclude that in particular the newly synthesized ependymin molecules are involved in memory consolidation, possibly because they have not yet undergone irreversible molecular changes, which have been reported of this glycoprotein in a low-calcium microenvironment.

Prism adaptation and generalization during visually guided locomotor tasks.

PubMed

Alexander, M Scott; Flodin, Brent W G; Marigold, Daniel S

2011-08-01

The ability of individuals to adapt locomotion to constraints associated with the complex environments normally encountered in everyday life is paramount for survival. Here, we tested the ability of 24 healthy young adults to adapt to a rightward prism shift (∼11.3°) while either walking and stepping to targets (i.e., precision stepping task) or stepping over an obstacle (i.e., obstacle avoidance task). We subsequently tested for generalization to the other locomotor task. In the precision stepping task, we determined the lateral end-point error of foot placement from the targets. In the obstacle avoidance task, we determined toe clearance and lateral foot placement distance from the obstacle before and after stepping over the obstacle. We found large, rightward deviations in foot placement on initial exposure to prisms in both tasks. The majority of measures demonstrated adaptation over repeated trials, and adaptation rates were dependent mainly on the task. On removal of the prisms, we observed negative aftereffects for measures of both tasks. Additionally, we found a unilateral symmetric generalization pattern in that the left, but not the right, lower limb indicated generalization across the 2 locomotor tasks. These results indicate that the nervous system is capable of rapidly adapting to a visuomotor mismatch during visually demanding locomotor tasks and that the prism-induced adaptation can, at least partially, generalize across these tasks. The results also support the notion that the nervous system utilizes an internal model for the control of visually guided locomotion.

Post-Traumatic Stress Avoidance is Attenuated by Corticosterone and Associated with Brain Levels of Steroid Receptor Co-Activator-1 in Rats

PubMed Central

Whitaker, Annie M.; Farooq, Muhammad A.; Edwards, Scott; Gilpin, Nicholas W.

2016-01-01

Individuals with post-traumatic stress disorder (PTSD) avoid trauma-related stimuli and exhibit blunted hypothalamic-pituitary-adrenal (HPA) axis activation at the time of stress. Our laboratory has established a rodent model of stress that mimics the avoidance symptom cluster of PTSD. Rats are classified as ‘Avoiders’ or ‘Non-Avoiders’ post-stress based on avoidance of a predator-odor paired context. Previously, we demonstrated that Avoiders exhibit an attenuated HPA stress response to predator odor. We hypothesized that corticosterone administration prior to stress would reduce magnitude and incidence of avoidance of a stress-paired context. Furthermore, we predicted that Avoiders would exhibit altered expression of GR signaling machinery elements, such as steroid receptor co-activator (SRC)-1. Male Wistar rats (n = 16) were pre-treated with corticosterone (25 mg/kg) or saline and exposed to predator odor stress paired with a context, and tested for avoidance 24 h later, A second group of corticosterone-naïve rats (n = 24) were stressed (or not stressed), indexed for avoidance 24 h later, and killed 48 h post-odor exposure for analysis of phosphorylated GR, FKBP51, and SRC-1 levels in the paraventricular nucleus (PVN), central amygdala (CeA) and ventral hippocampus (VH), all brain sites that express high quantities of GRs and regulate HPA function. Rats pre-treated with corticosterone exhibited lower magnitude and incidence of avoidance. Predator odor exposure also reduced SRC-1 expression in the PVN and CeA of Avoiders, and increased SRC-1 expression in the VH of Avoiders. SRC-1 expression in PVN, CeA, and VH was predicted by prior avoidance behavior. These results suggest that blunted HPA stress response may contribute to stress-induced neuroadaptations in central SRC-1 levels and behavioral dysfunction in Avoider rats. PMID:26482332

Two-photon imaging of neuronal activity in motor cortex of marmosets during upper-limb movement tasks.

PubMed

Ebina, Teppei; Masamizu, Yoshito; Tanaka, Yasuhiro R; Watakabe, Akiya; Hirakawa, Reiko; Hirayama, Yuka; Hira, Riichiro; Terada, Shin-Ichiro; Koketsu, Daisuke; Hikosaka, Kazuo; Mizukami, Hiroaki; Nambu, Atsushi; Sasaki, Erika; Yamamori, Tetsuo; Matsuzaki, Masanori

2018-05-14

Two-photon imaging in behaving animals has revealed neuronal activities related to behavioral and cognitive function at single-cell resolution. However, marmosets have posed a challenge due to limited success in training on motor tasks. Here we report the development of protocols to train head-fixed common marmosets to perform upper-limb movement tasks and simultaneously perform two-photon imaging. After 2-5 months of training sessions, head-fixed marmosets can control a manipulandum to move a cursor to a target on a screen. We conduct two-photon calcium imaging of layer 2/3 neurons in the motor cortex during this motor task performance, and detect task-relevant activity from multiple neurons at cellular and subcellular resolutions. In a two-target reaching task, some neurons show direction-selective activity over the training days. In a short-term force-field adaptation task, some neurons change their activity when the force field is on. Two-photon calcium imaging in behaving marmosets may become a fundamental technique for determining the spatial organization of the cortical dynamics underlying action and cognition.

The time course of location-avoidance learning in fear of spiders.

PubMed

Rinck, Mike; Koene, Marieke; Telli, Sibel; Moerman-van den Brink, Wiltine; Verhoeven, Barbara; Becker, Eni S

2016-01-01

Two experiments were designed to study the time course of avoidance learning in spider fearfuls (SFs) under controlled experimental conditions. To achieve this, we employed an immersive virtual environment (IVE): While walking freely through a virtual art museum to search for specific paintings, the participants were exposed to virtual spiders. Unbeknown to the participants, only two of four museum rooms contained spiders, allowing for avoidance learning. Indeed, the more SF the participants were, the faster they learned to avoid the rooms that contained spiders (Experiment. 1), and within the first six trials, high fearfuls already developed a preference for starting their search task in rooms without spiders (Experiment 2). These results illustrate the time course of avoidance learning in SFs, and they speak to the usefulness of IVEs in fundamental anxiety research.

Methodology for Determining the Avoidable and Fully Allocated Costs of Amtrak Routes : Volume III, Appendix B-H

DOT National Transportation Integrated Search

2009-08-01

The Federal Railroad Administration tasked the Volpe Center with developing a methodology for determining the avoidable and fully allocated costs of Amtrak routes. Avoidable costs are costs that would not be incurred if an Amtrak route were discontin...

Comparison of pro-amnesic efficacy of scopolamine, biperiden, and phencyclidine by using passive avoidance task in CD-1 mice.

PubMed

Malikowska, Natalia; Sałat, Kinga; Podkowa, Adrian

2017-07-01

Memory disorders accompany numerous diseases and therapies, and this is becoming a growing medical issue worldwide. Currently, various animal models of memory impairments are available; however, many of them require high financial outlay and/or are time-consuming. A simple way to achieve an efficient behavioral model of cognitive disorders is to inject defined drug that has pro-amnesic properties. Since the involvement of cholinergic and glutamatergic neurotransmission in cognition is well established, the utilization of a nonselective muscarinic receptor antagonist, scopolamine (SCOP), a selective M1 muscarinic receptor antagonist, biperiden (BIP), and a non-competitive N-methyl-d-aspartate (NMDA) receptor antagonist, phencyclidine (PCP) seems to be reliable tools to induce amnesia. As the determination of their effective doses remains vague and the active doses vary significantly in laboratory settings and in mouse species being tested, the aim of this study was to compare these three models of amnesia in CD-1 mice. Male Swiss Albino mice were used in passive avoidance (PA) test. All the compounds were administered intraperitoneally (ip) at doses 1mg/kg, 5mg/kg, and 10mg/kg (SCOP and BIP), and 1mg/kg, 3mg/kg, and 6mg/kg (PCP). In the retention trial of the PA task, SCOP and PCP led to the reduction of step-through latency at all the tested doses as compared to control, but BIP was effective only at the dose of 10mg/kg. This study revealed the effectiveness of SCOP, PCP, and BIP as tools to induce amnesia, with the PCP model being the most efficacious and SCOP being the only model that demonstrates a clear dose-response relationship. Copyright © 2017. Published by Elsevier Inc.

Advanced Marketing 8130. Instructional Areas. Duties and Tasks. Learning Activities. Referenced Resources.

ERIC Educational Resources Information Center

Virginia State Dept. of Education, Richmond.

This resource handbook, which is designed for use by instructors of courses in advanced marketing, consists of a duty/task list with referenced resources, a duty/task list with learning activities, and a list of resources. Included in each list are materials dealing with the following topics: communication in marketing, economics in marketing,…

ALHAT: Autonomous Landing and Hazard Avoidance Technology

NASA Technical Reports Server (NTRS)

Robertson, Edward A.; Carson, John M., III

2015-01-01

The ALHAT project was chartered by NASA HQ in 2006 to develop and mature to TRL 6 an autonomous lunar landing GN&C and sensing system for crewed, cargo, and robotic planetary landing vehicles. The multi-center ALHAT team was tasked with providing a system capable of identifying and avoiding surface hazards in real time to enable safe precision landing to within tens of meters of a designated planetary landing site under any lighting conditions.

Embodied simulation as part of affective evaluation processes: task dependence of valence concordant EMG activity.

PubMed

Weinreich, André; Funcke, Jakob Maria

2014-01-01

Drawing on recent findings, this study examines whether valence concordant electromyography (EMG) responses can be explained as an unconditional effect of mere stimulus processing or as somatosensory simulation driven by task-dependent processing strategies. While facial EMG over the Corrugator supercilii and the Zygomaticus major was measured, each participant performed two tasks with pictures of album covers. One task was an affective evaluation task and the other was to attribute the album covers to one of five decades. The Embodied Emotion Account predicts that valence concordant EMG is more likely to occur if the task necessitates a somatosensory simulation of the evaluative meaning of stimuli. Results support this prediction with regard to Corrugator supercilii in that valence concordant EMG activity was only present in the affective evaluation task but not in the non-evaluative task. Results for the Zygomaticus major were ambiguous. Our findings are in line with the view that EMG activity is an embodied part of the evaluation process and not a mere physical outcome.

Fear-avoidance beliefs and parental responses to pain in adolescents with chronic pain.

PubMed

Wilson, Anna C; Lewandowski, Amy S; Palermo, Tonya M

2011-01-01

The fear-avoidance model of chronic pain posits that fear of pain is associated with fear and avoidance of activity, which can lead to deconditioning and persistence of pain and disability. Despite being well supported in adults, little is known about the role of fear-avoidance beliefs regarding physical activity in children. Research has shown that parental protectiveness contributes to activity limitations in children; however, no studies have examined relationships between protectiveness, and fear and avoidance. To conduct a cross-sectional study to provide additional information regarding the reliability and validity of the Fear-Avoidance Beliefs Questionnaire physical activity subscale among adolescents with chronic pain; examine fear-avoidance beliefs and depressive symptoms as concurrent predictors of physical activity limitations; and test competing models using fear-avoidance beliefs as mediators and moderators of the association between parental protectiveness and activity limitations. Adolescents (n=42) 11 to 17 years of age with chronic pain completed questionnaires assessing pain intensity, fear-avoidance beliefs, depressive symptoms and physical activity limitations. Their parents completed questionnaires regarding protectiveness and adolescent activity limitations. The Fear-Avoidance Beliefs Questionnaire physical activity subscale was useful for assessing fear-avoidance beliefs in the present population. In support of hypotheses, greater fear-avoidance beliefs were associated with greater activity limitations, above pain intensity and depressive symptoms. Support was found for fear-avoidance beliefs as mediators of the association between parental protectiveness and activity limitations. Tests of moderation were not significant. Fear-avoidance beliefs may be an important target for interventions focused on decreasing activity limitations in youth with chronic pain. Future research should investigate these associations longitudinally.

A neural measure of behavioral engagement: task-residual low-frequency blood oxygenation level-dependent activity in the precuneus.

PubMed

Zhang, Sheng; Li, Chiang-Shan Ray

2010-01-15

Brain imaging has provided a useful tool to examine the neural processes underlying human cognition. A critical question is whether and how task engagement influences the observed regional brain activations. Here we highlighted this issue and derived a neural measure of task engagement from the task-residual low-frequency blood oxygenation level-dependent (BOLD) activity in the precuneus. Using independent component analysis, we identified brain regions in the default circuit - including the precuneus and medial prefrontal cortex (mPFC) - showing greater activation during resting as compared to task residuals in 33 individuals. Time series correlations with the posterior cingulate cortex as the seed region showed that connectivity with the precuneus was significantly stronger during resting as compared to task residuals. We hypothesized that if the task-residual BOLD activity in the precuneus reflects engagement, it should account for a certain amount of variance in task-related regional brain activation. In an additional experiment of 59 individuals performing a stop signal task, we observed that the fractional amplitude of low-frequency fluctuation (fALFF) of the precuneus but not the mPFC accounted for approximately 10% of the variance in prefrontal activation related to attentional monitoring and response inhibition. Taken together, these results suggest that task-residual fALFF in the precuneus may be a potential indicator of task engagement. This measurement may serve as a useful covariate in identifying motivation-independent neural processes that underlie the pathogenesis of a psychiatric or neurological condition.

Pathological gambling and alcohol dependence: neural disturbances in reward and loss avoidance processing.

PubMed

Romanczuk-Seiferth, Nina; Koehler, Saskia; Dreesen, Caspar; Wüstenberg, Torsten; Heinz, Andreas

2015-05-01

Pathological gambling (PG) shares clinical characteristics such as craving and loss of control with substance use disorders and is thus considered a behavioral addiction. While functional alterations in the mesolimbic reward system have been correlated with craving and relapse in substance use disorders, only a few studies have examined this brain circuit in PG, and no direct comparison has been conducted so far. Thus, we investigated the neuronal correlates of reward processing in PG in contrast to alcohol-dependent (AD) patients and healthy subjects. Eighteen PG patients, 15 AD patients and 17 controls were investigated with a monetary incentive delay task, in which visual cues predict the consequence (monetary gain, avoidance of loss, none) of a fast response to a subsequent target stimulus. Functional magnetic resonance imaging data were analyzed to account for possible confounding factors such as local gray matter volume. Activity in the right ventral striatum during loss anticipation was increased in PG patients compared with controls and AD patients. Moreover, PG patients showed decreased activation in the right ventral striatum and right medial prefrontal cortex during successful loss avoidance compared with controls, which was inversely associated with severity of gambling behavior. Thus, despite neurobiological similarities to substance use disorders in reward processing, as reported by previous studies, we found relevant differences with respect to the anticipation of loss as well as its avoidance (negative reinforcement), which further contributes to the understanding of PG. © 2014 Society for the Study of Addiction.

The push and pull of grief: Approach and avoidance in bereavement.

PubMed

Maccallum, Fiona; Sawday, Simon; Rinck, Mike; Bryant, Richard A

2015-09-01

Prolonged Grief (PG) is recognized as a post-bereavement syndrome that is associated with significant impairment. Although approach and avoidance tendencies have both been hypothesized to play key roles in maintaining PG symptoms, understanding of these relationships has been limited by a reliance on self-report methodology. This study applies an experimental paradigm to simultaneously investigate the relationship between PG severity and approach-avoidance behavioral tendencies. Fifty-five bereaved individuals with and without PG completed a behavioral measure of approach and avoidance responding in which they pulled or pushed a joystick in response to grief-related, positive, negative and neutral images that appeared on a computer screen. Concurrent visual feedback created the illusion that the images were either approaching or receding from the participant. Half of the participants also received a prime designed to activate their grief prior to the task. Irrespective of prime condition, PG participants pulled grief-related images more quickly than they pushed them. This difference was not observed in response to non-grief related images. Non PG participants showed no difference in their reaction times to grief-stimuli. This study was undertaken in a nonclinical setting and the majority of participants had lost a loved one due to chronic illness. Future research with treatment-seeking populations and sudden loss will be needed to explore the generalizability of the findings. The findings from this study provide preliminary evidence supporting models of PG that integrate approach and avoidance tendencies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Unintended activity in homologous muscle during intended unilateral contractions increases with greater task difficulty.

PubMed

Watanabe, Hironori; Kanehisa, Hiroaki; Yoshitake, Yasuhide

2017-10-01

The present study aimed to examine (1) the effect of task difficulty on unintended muscle activation (UIMA) levels in contralateral homologous muscle, (2) the difference between young and old adults in degree of UIMA with respect to task difficulty, and (3) temporal correlations between intended and contralateral unintended muscle activity at low frequency during unilateral intended force-matching tasks. Twelve young (21.8 ± 2.4 years) and twelve old (69.9 ± 5.3 years) adult men performed steady isometric abductions with the left index finger at 20-80% of maximal voluntary contraction force. Two task difficulties were set by adjusting the spacing between two bars centered about the target force used for visual feedback on a monitor. The amplitude of surface electromyogram (aEMG) for both hands was calculated and normalized with respect to the maximal value. To determine if oscillations between intended and unintended muscle activities were correlated, cross-correlation function (CCF) of rectified EMG for both hands at low frequency was calculated for samples deemed adequate. The unintended aEMG (right hand) had significant main effects in task difficulty, age, and target force (all P < 0.05) without any interactions. Distinct significant peaks in CCF (0.38 on average, P < 0.05) with small time lags were present between rectified EMGs of intended and unintended muscles in 14 of the 17 samples. The current results indicate that UIMA increases with greater task difficulty regardless of age, and temporal correlations exist between intended and contralateral unintended muscle activities at low frequency.

Comparison of fMRI data from passive listening and active-response story processing tasks in children

PubMed Central

Vannest, Jennifer J.; Karunanayaka, Prasanna R.; Altaye, Mekibib; Schmithorst, Vincent J.; Plante, Elena M.; Eaton, Kenneth J.; Rasmussen, Jerod M.; Holland, Scott K.

2009-01-01

Purpose To use functional MRI methods to visualize a network of auditory and language-processing brain regions associated with processing an aurally-presented story. We compare a passive listening (PL) story paradigm to an active-response (AR) version including on-line performance monitoring and a sparse acquisition technique. Materials/Methods Twenty children (ages 11−13) completed PL and AR story processing tasks. The PL version presented alternating 30-second blocks of stories and tones; the AR version presented story segments, comprehension questions, and 5s tone sequences, with fMRI acquisitions between stimuli. fMRI data was analyzed using a general linear model approach and paired t-test identifying significant group activation. Results Both tasks activated in primary auditory cortex, superior temporal gyrus bilaterally, left inferior frontal gyrus. The AR task demonstrated more extensive activation, including dorsolateral prefrontal cortex and anterior/posterior cingulate cortex. Comparison of effect size in each paradigm showed a larger effect for the AR paradigm in a left inferior frontal ROI. Conclusion Activation patterns for story processing in children are similar in passive listening and active-response tasks. Increases in extent and magnitude of activation in the AR task are likely associated with memory and attention resources engaged across acquisition intervals. PMID:19306445

Remote Maneuver of Space Debris Using Photon Pressure for Active Collision Avoidance

NASA Astrophysics Data System (ADS)

Smith, C.

2014-09-01

The Space Environment Research Corporation (SERC) is a consortium of companies and research institutions that have joined together to pursue research and development of technologies and capabilities that will help to preserve the orbital space environment. The consortium includes, Electro Optics Systems (Australia), Lockheed Martin Australia, Optus Satellite Systems (Australia), The Australian national University, RMIT University, National Institute of Information and Communications Technology (NICT, Japan) as well as affiliates from NASA Ames and ESA. SERC is also the recipient of and Australian Government Cooperative Research Centre grant. SERC will pursue a wide ranging research program including technologies to improve tracking capability and capacity, orbit determination and propagation algorithms, conjunction analysis and collision avoidance. All of these technologies will contribute to the flagship program to demonstrate active collision avoidance using photon pressure to provide remote maneuver of space debris. This project joins of the proposed NASA Lightforce concept with infrastructure and capabilities provided by SERC. This paper will describe the proposed research and development program to provide an on-orbit demonstration within the next five years for remote maneuver of space debris.

Frontal brain activation during a working memory task: a time-domain fNIRS study

NASA Astrophysics Data System (ADS)

Molteni, E.; Baselli, G.; Bianchi, A. M.; Caffini, M.; Contini, D.; Spinelli, L.; Torricelli, A.; Cerutti, S.; Cubeddu, R.

2009-02-01

We evaluated frontal brain activation during a working memory task with graded levels of difficulty in a group of 19 healthy subjects, by means of time-resolved fNIRS technique. Brain activation was computed, and was then separated into a "block-related" and a "tonic" components. Load-related increases of blood oxygenation were studied for the four different levels of task difficulty. Generalized Linear Models were applied to the data in order to explore the metabolic processes occurring during the mental effort and, possibly, their involvement in short term memorization. Results attest the presence of a persistent attentional-related metabolic activity, superimposed to a task-related mnemonic contribution. Moreover, a systemic component probably deriving from the extra-cerebral capillary bed was detected.

Reward sensitivity modulates brain activity in the prefrontal cortex, ACC and striatum during task switching.

PubMed

Fuentes-Claramonte, Paola; Ávila, César; Rodríguez-Pujadas, Aina; Ventura-Campos, Noelia; Bustamante, Juan C; Costumero, Víctor; Rosell-Negre, Patricia; Barrós-Loscertales, Alfonso

2015-01-01

Current perspectives on cognitive control acknowledge that individual differences in motivational dispositions may modulate cognitive processes in the absence of reward contingencies. This work aimed to study the relationship between individual differences in Behavioral Activation System (BAS) sensitivity and the neural underpinnings involved in processing a switching cue in a task-switching paradigm. BAS sensitivity was hypothesized to modulate brain activity in frontal regions, ACC and the striatum. Twenty-eight healthy participants underwent fMRI while performing a switching task, which elicited activity in fronto-striatal regions during the processing of the switch cue. BAS sensitivity was negatively associated with activity in the lateral prefrontal cortex, anterior cingulate cortex and the ventral striatum. Combined with previous results, our data indicate that BAS sensitivity modulates the neurocognitive processes involved in task switching in a complex manner depending on task demands. Therefore, individual differences in motivational dispositions may influence cognitive processing in the absence of reward contingencies.

Reward Sensitivity Modulates Brain Activity in the Prefrontal Cortex, ACC and Striatum during Task Switching

PubMed Central

Fuentes-Claramonte, Paola; Ávila, César; Rodríguez-Pujadas, Aina; Ventura-Campos, Noelia; Bustamante, Juan C.; Costumero, Víctor; Rosell-Negre, Patricia; Barrós-Loscertales, Alfonso

2015-01-01

Current perspectives on cognitive control acknowledge that individual differences in motivational dispositions may modulate cognitive processes in the absence of reward contingencies. This work aimed to study the relationship between individual differences in Behavioral Activation System (BAS) sensitivity and the neural underpinnings involved in processing a switching cue in a task-switching paradigm. BAS sensitivity was hypothesized to modulate brain activity in frontal regions, ACC and the striatum. Twenty-eight healthy participants underwent fMRI while performing a switching task, which elicited activity in fronto-striatal regions during the processing of the switch cue. BAS sensitivity was negatively associated with activity in the lateral prefrontal cortex, anterior cingulate cortex and the ventral striatum. Combined with previous results, our data indicate that BAS sensitivity modulates the neurocognitive processes involved in task switching in a complex manner depending on task demands. Therefore, individual differences in motivational dispositions may influence cognitive processing in the absence of reward contingencies. PMID:25875640

Beyond negligence: avoidability and medical injury compensation.

PubMed

Kachalia, Allen B; Mello, Michelle M; Brennan, Troyen A; Studdert, David M

2008-01-01

improve patient safety, and the avoidability standard appears to be well suited for this task.

Sex differences on a mental rotation task: variations in electroencephalogram hemispheric activation between children and college students.

PubMed

Roberts, J E; Bell, M A

2000-01-01

The area of cognitive research that has produced the most consistent sex differences is spatial ability. In particular, men usually perform better on mental rotation tasks than women. Performance on mental rotation tasks has been associated with right parietal activation levels, both during task performance and prior to performance during baseline recordings. This study examined the relations among sex, age, electroencephalogram (EEG) hemispheric activation (at the 10.5 Hz to 13.5 Hz frequency band), and 2-D mental rotation task ability. Nineteen 8-year-olds (10 boys) and 20 college students (10 men) had EEG recorded at baseline and while performing a mental rotation task. Men had a faster reaction time on the mental rotation task than women, whereas there were no differences between boys and girls. After covarying for baseline EEG power values, men exhibited more activation (lower EEG power values) than women in the parietal and posterior temporal regions, whereas boys' and girls' power values did not differ in the parietal or posterior temporal regions. Furthermore, during the baseline condition, men generally exhibited more activation (lower EEG power values) throughout all regions of the scalp. Results support the hypothesis that a change that affects both brain activation and performance on mental rotation tasks occurs sometime between childhood and adulthood.

Gap junctions and memory: an investigation using a single trial discrimination avoidance task for the neonate chick.

PubMed

Verwey, L J; Edwards, T M

2010-02-01

Gap junctions are important to how the brain functions but are relatively under-investigated with respect to their contribution towards behaviour. In the present study a single trial discrimination avoidance task was used to investigate the effect of the gap junction inhibitor 18-alpha-glycyrrhetinic acid (alphaGA) on retention. Past studies within our research group have implied a potential role for gap junctions during the short-term memory (STM) stage which decays by 15 min post-training. A retention function study comparing 10 microM alphaGA and vehicle given immediately post-training demonstrated a significant main effect for drug with retention loss at all times of test (10-180 min post-training). Given that the most common gap junction in the brain is that forming the astrocytic network it is reasonable to conclude that alphaGA was acting upon these. To confirm this finding and interpretation two additional investigations were undertaken using endothelin-1 (ET-1) and ET-1+tolbutamide. Importantly, a retention function study using 10nM ET-1 replicated the retention loss observed for alphaGA. In order to confirm that ET-1 was acting on astrocytic gap junctions the amnestic action of ET-1 was effectively challenged with increasing concentrations of tolbutamide. The present findings suggest that astrocytic gap junctions are important for memory processing. Copyright 2009 Elsevier Inc. All rights reserved.

Parsing the Role of the Hippocampus in Approach-Avoidance Conflict.

PubMed

Loh, Eleanor; Kurth-Nelson, Zeb; Berron, David; Dayan, Peter; Duzel, Emrah; Dolan, Ray; Guitart-Masip, Marc

2017-01-01

The hippocampus plays a central role in the approach-avoidance conflict that is central to the genesis of anxiety. However, its exact functional contribution has yet to be identified. We designed a novel gambling task that generated approach-avoidance conflict while controlling for spatial processing. We fit subjects' behavior using a model that quantified the subjective values of choice options, and recorded neural signals using functional magnetic resonance imaging (fMRI). Distinct functional signals were observed in anterior hippocampus, with inferior hippocampus selectively recruited when subjects rejected a gamble, to a degree that covaried with individual differences in anxiety. The superior anterior hippocampus, in contrast, uniquely demonstrated value signals that were potentiated in the context of approach-avoidance conflict. These results implicate the anterior hippocampus in behavioral avoidance and choice monitoring, in a manner relevant to understanding its role in anxiety. Our findings highlight interactions between subregions of the hippocampus as an important focus for future study. © The Author 2016. Published by Oxford University Press.

Parsing the Role of the Hippocampus in Approach–Avoidance Conflict

PubMed Central

Loh, Eleanor; Kurth-Nelson, Zeb; Berron, David; Dayan, Peter; Duzel, Emrah; Dolan, Ray; Guitart-Masip, Marc

2017-01-01

Abstract The hippocampus plays a central role in the approach–avoidance conflict that is central to the genesis of anxiety. However, its exact functional contribution has yet to be identified. We designed a novel gambling task that generated approach–avoidance conflict while controlling for spatial processing. We fit subjects’ behavior using a model that quantified the subjective values of choice options, and recorded neural signals using functional magnetic resonance imaging (fMRI). Distinct functional signals were observed in anterior hippocampus, with inferior hippocampus selectively recruited when subjects rejected a gamble, to a degree that covaried with individual differences in anxiety. The superior anterior hippocampus, in contrast, uniquely demonstrated value signals that were potentiated in the context of approach–avoidance conflict. These results implicate the anterior hippocampus in behavioral avoidance and choice monitoring, in a manner relevant to understanding its role in anxiety. Our findings highlight interactions between subregions of the hippocampus as an important focus for future study. PMID:27993819

Dual-Task Performance: Influence of Frailty, Level of Physical Activity, and Cognition.

PubMed

Giusti Rossi, Paulo; Pires de Andrade, Larissa; Hotta Ansai, Juliana; Silva Farche, Ana Claudia; Carnaz, Leticia; Dalpubel, Daniela; Ferriolli, Eduardo; Assis Carvalho Vale, Francisco; de Medeiros Takahashi, Anielle Cristhine

2018-03-08

Cognition and level of physical activity have been associated with frailty syndrome. The development of tools that assess deficits related to physical and cognitive frailties simultaneously are of common interest. However, little is known about how much these aspects influence the performance of dual-task tests. Our aims were (a) to verify the influence of frailty syndrome and objectively measured physical activity and cognition on the Timed Up and Go (TUG) test and Timed Up and Go associated with dual-task (TUG-DT) performances; and (b) to compare TUG and TUG-DT performances between older adults who develop frailty syndrome. Sixty-four community-dwelling older adults were divided into frail, prefrail, and nonfrail groups, according to frailty phenotype. Assessments included anamnesis, screening of frailty syndrome, cognitive assessment (Addenbrooke's cognitive examination), placement of a triaxial accelerometer to assess level of physical activity, and TUG and TUG-DT (TUG associated with a motor-cognitive task of calling a phone number) performances. After 7 days, the accelerometer was removed. A multiple linear regression was applied to identify which independent variables could explain performances in the TUG and TUG-DT. Subsequently, the analysis of covariance test, adjusted for age, cognition, and level of physical activity covariates, was used to compare test performances. There were no differences in cognition between groups. Significant differences in the level of physical activity were found in the frail group. Compared with the frail group, the nonfrail group required less time and fewer steps to complete the TUG. Regarding the TUG-DT, cognition and age influenced the time spent and number of steps, respectively; however, no differences were found between groups. Frail older adults presented worse performance in the TUG when compared with nonfrail older adults. The dual-task test does not differentiate older adults with frailty syndrome, regardless of

Active listening: task-dependent plasticity of spectrotemporal receptive fields in primary auditory cortex.

PubMed

Fritz, Jonathan; Elhilali, Mounya; Shamma, Shihab

2005-08-01

Listening is an active process in which attentive focus on salient acoustic features in auditory tasks can influence receptive field properties of cortical neurons. Recent studies showing rapid task-related changes in neuronal spectrotemporal receptive fields (STRFs) in primary auditory cortex of the behaving ferret are reviewed in the context of current research on cortical plasticity. Ferrets were trained on spectral tasks, including tone detection and two-tone discrimination, and on temporal tasks, including gap detection and click-rate discrimination. STRF changes could be measured on-line during task performance and occurred within minutes of task onset. During spectral tasks, there were specific spectral changes (enhanced response to tonal target frequency in tone detection and discrimination, suppressed response to tonal reference frequency in tone discrimination). However, only in the temporal tasks, the STRF was changed along the temporal dimension by sharpening temporal dynamics. In ferrets trained on multiple tasks, distinctive and task-specific STRF changes could be observed in the same cortical neurons in successive behavioral sessions. These results suggest that rapid task-related plasticity is an ongoing process that occurs at a network and single unit level as the animal switches between different tasks and dynamically adapts cortical STRFs in response to changing acoustic demands.

Comparison of fMRI data from passive listening and active-response story processing tasks in children.

PubMed

Vannest, Jennifer J; Karunanayaka, Prasanna R; Altaye, Mekibib; Schmithorst, Vincent J; Plante, Elena M; Eaton, Kenneth J; Rasmussen, Jerod M; Holland, Scott K

2009-04-01

To use functional MRI (fMRI) methods to visualize a network of auditory and language-processing brain regions associated with processing an aurally-presented story. We compare a passive listening (PL) story paradigm to an active-response (AR) version including online performance monitoring and a sparse acquisition technique. Twenty children (ages 11-13 years) completed PL and AR story processing tasks. The PL version presented alternating 30-second blocks of stories and tones; the AR version presented story segments, comprehension questions, and 5-second tone sequences, with fMRI acquisitions between stimuli. fMRI data was analyzed using a general linear model approach and paired t-test identifying significant group activation. Both tasks showed activation in the primary auditory cortex, superior temporal gyrus bilaterally, and left inferior frontal gyrus (IFG). The AR task demonstrated more extensive activation, including the dorsolateral prefrontal cortex and anterior/posterior cingulate cortex. Comparison of effect size in each paradigm showed a larger effect for the AR paradigm in a left inferior frontal region-of-interest (ROI). Activation patterns for story processing in children are similar in PL and AR tasks. Increases in extent and magnitude of activation in the AR task are likely associated with memory and attention resources engaged across acquisition intervals.

Effects of task complexity on activation of language areas in a semantic decision fMRI protocol.

PubMed

Lopes, Tátila Martins; Yasuda, Clarissa Lin; de Campos, Brunno Machado; Balthazar, Marcio L F; Binder, Jeffrey R; Cendes, Fernando

2016-01-29

Language tasks used for clinical fMRI studies may be too complex for some patients with cognitive impairments, and "easier" versions are sometimes substituted, though the effects on brain activity of such changes in task complexity are largely unknown. To investigate these differences, we compared two versions of an fMRI language comprehension protocol, with different levels of difficulty, in 24 healthy right-handed adults. The protocol contrasted an auditory word comprehension task (semantic decision) with a nonspeech control task using tone sequences (tone decision). In the "complex" version (CV), the semantic decision task required two complex semantic decisions for each word, and the tone decision task required the participant to count the number of target tones in each sequence. In the "easy" version (EV), the semantic task required only a single easier decision, and the tone task required only detection of the presence or absence of a target tone in each sequence. The protocols were adapted for a Brazilian population. Typical left hemisphere language lateralization was observed in 92% of participants for both CV and EV using the whole-brain lateralization index, and typical language lateralization was also observed for others regions of interest. Task performance was superior on the EV compared to the CV (p=0.014). There were many common areas of activation across the two version; however, the CV produced greater activation in the left superior and middle frontal giri, angular gyrus, and left posterior cingulate gyrus compared to the EV, the majority of which are areas previously identified with language and semantic processing. The EV produced stronger activation only in a small area in the posterior middle temporal gyrus. These results reveal differences between two versions of the protocol and provide evidence that both are useful for language lateralization and worked well for Brazilian population. The complex version produces stronger activation in

Intrahippocampal Insulin Improves Memory in a Passive-Avoidance Task in Male Wistar Rats

ERIC Educational Resources Information Center

Babri, Shirin; Badie, Hamid Gholamipour; Khamenei, Saeed; Seyedlar, Mehdi Ordikhani

2007-01-01

The main impacts of insulin favor the peripheral organs. Although it functions as a neuropeptide, insulin possesses also some central effects. The aim of this study was to determine the effect of intrahippocampal infusion of insulin on passive avoidance learning in healthy male rats. Thirty male wistar rats were divided into three groups (n = 10…

Analysis of Time-Dependent Brain Network on Active and MI Tasks for Chronic Stroke Patients

PubMed Central

Chang, Won Hyuk; Kim, Yun-Hee; Lee, Seong-Whan; Kwon, Gyu Hyun

2015-01-01

Several researchers have analyzed brain activities by investigating brain networks. However, there is a lack of the research on the temporal characteristics of the brain network during a stroke by EEG and the comparative studies between motor execution and imagery, which became known to have similar motor functions and pathways. In this study, we proposed the possibility of temporal characteristics on the brain networks of a stroke. We analyzed the temporal properties of the brain networks for nine chronic stroke patients by the active and motor imagery tasks by EEG. High beta band has a specific role in the brain network during motor tasks. In the high beta band, for the active task, there were significant characteristics of centrality and small-worldness on bilateral primary motor cortices at the initial motor execution. The degree centrality significantly increased on the contralateral primary motor cortex, and local efficiency increased on the ipsilateral primary motor cortex. These results indicate that the ipsilateral primary motor cortex constructed a powerful subnetwork by influencing the linked channels as compensatory effect, although the contralateral primary motor cortex organized an inefficient network by using the connected channels due to lesions. For the MI task, degree centrality and local efficiency significantly decreased on the somatosensory area at the initial motor imagery. Then, there were significant correlations between the properties of brain networks and motor function on the contralateral primary motor cortex and somatosensory area for each motor execution/imagery task. Our results represented that the active and MI tasks have different mechanisms of motor acts. Based on these results, we indicated the possibility of customized rehabilitation according to different motor tasks. We expect these results to help in the construction of the customized rehabilitation system depending on motor tasks by understanding temporal functional

Subjective Significance Shapes Arousal Effects on Modified Stroop Task Performance: A Duality of Activation Mechanisms Account.

PubMed

Imbir, Kamil K

2016-01-01

Activation mechanisms such as arousal are known to be responsible for slowdown observed in the Emotional Stroop and modified Stroop tasks. Using the duality of mind perspective, we may conclude that both ways of processing information (automatic or controlled) should have their own mechanisms of activation, namely, arousal for an experiential mind, and subjective significance for a rational mind. To investigate the consequences of both, factorial manipulation was prepared. Other factors that influence Stroop task processing such as valence, concreteness, frequency, and word length were controlled. Subjective significance was expected to influence arousal effects. In the first study, the task was to name the color of font for activation charged words. In the second study, activation charged words were, at the same time, combined with an incongruent condition of the classical Stroop task around a fixation point. The task was to indicate the font color for color-meaning words. In both studies, subjective significance was found to shape the arousal impact on performance in terms of the slowdown reduction for words charged with subjective significance.

The Association Between Weight Status, Weight History, Physical Activity, and Cognitive Task Performance.

PubMed

Edwards, Meghan K; Dankel, Scott J; Loenneke, Jeremy P; Loprinzi, Paul D

2017-06-01

Physical activity has been shown to attenuate the association between overweight/obesity and deleterious cardiovascular health-related outcomes, with emerging work also taking the duration of overweight/obesity into consideration. No previous work, however, has explored the interrelationships between physical activity, obesity, and obesity duration in the context of cognitive task performance, which was the purpose of this study. Data from the 1999-2002 National Health and Nutrition Examination Survey were used (N = 2322 adults 60-85 yrs). Physical activity was assessed via self-report, with body mass index (BMI) directly measured. Participants were classified into one of eight mutually exclusive groups: (0) normal weight now and 10 years ago and active now (n = 195), (1) normal weight and 10 years ago and inactive now (n = 265), (2) normal weight now but not 10 years ago and active now (n = 46), (3) normal weight now but not 10 years ago and inactive now (n = 123), (4) overweight/obese now but not 10 years ago and active now (n = 117), (5) overweight/obese now but not 10 years ago and inactive now (n = 168), (6) overweight/obese now and 10 years ago and active now (n = 435), and (7) overweight/obese now and 10 years ago and inactive now (n = 973). The digit symbol substitution test (DSST) was employed to assess cognitive task performance. After adjustments, only individuals who were inactive (groups 1, 3, 5, and 7) had significantly lower cognitive task performance. Being inactive, regardless of weight classification and duration of overweight/obesity, was inversely associated with cognitive task performance in this national sample of older adults.

Is All Motivation Good for Learning? Dissociable Influences of Approach and Avoidance Motivation in Declarative Memory

ERIC Educational Resources Information Center

Murty, Vishnu P.; LaBar, Kevin S.; Hamilton, Derek A.; Adcock, R. Alison

2011-01-01

The present study investigated the effects of approach versus avoidance motivation on declarative learning. Human participants navigated a virtual reality version of the Morris water task, a classic spatial memory paradigm, adapted to permit the experimental manipulation of motivation during learning. During this task, participants were instructed…

Coordinated Dynamic Behaviors for Multirobot Systems With Collision Avoidance.

PubMed

Sabattini, Lorenzo; Secchi, Cristian; Fantuzzi, Cesare

2017-12-01

In this paper, we propose a novel methodology for achieving complex dynamic behaviors in multirobot systems. In particular, we consider a multirobot system partitioned into two subgroups: 1) dependent and 2) independent robots. Independent robots are utilized as a control input, and their motion is controlled in such a way that the dependent robots solve a tracking problem, that is following arbitrarily defined setpoint trajectories, in a coordinated manner. The control strategy proposed in this paper explicitly addresses the collision avoidance problem, utilizing a null space-based behavioral approach: this leads to combining, in a non conflicting manner, the tracking control law with a collision avoidance strategy. The combination of these control actions allows the robots to execute their task in a safe way. Avoidance of collisions is formally proven in this paper, and the proposed methodology is validated by means of simulations and experiments on real robots.

Closing your eyes to follow your heart: Avoiding information to protect a strong intuitive preference.

PubMed

Woolley, Kaitlin; Risen, Jane L

2018-02-01

Rationally, people should want to receive information that is costless and relevant for a decision. But people sometimes choose to remain ignorant. The current paper identifies intuitive-deliberative conflict as a driver of information avoidance. Moreover, we examine whether people avoid information not only to protect their feelings or experiences, but also to protect the decision itself. We predict that people avoid information that could encourage a more thoughtful, deliberative decision to make it easier to enact their intuitive preference. In Studies 1 and 2, people avoid learning the calories in a tempting dessert and compensation for a boring task to protect their preferences to eat the dessert and work on a more enjoyable task. The same people who want to avoid the information, however, use it when it is provided. In Studies 3-5, people decide whether to learn how much money they could earn by accepting an intuitively unappealing bet (that a sympathetic student performs poorly or that a hurricane hits a third-world country). Although intuitively unappealing, the bets are financially rational because they only have financial upside. If people avoid information in part to protect their intuitive preference, then avoidance should be greater when an intuitive preference is especially strong and when information could influence the decision. As predicted, avoidance is driven by the strength of the intuitive preference (Study 3) and, ironically, information avoidance is greater before a decision is made, when the information is decision relevant, than after, when the information is irrelevant for the decision (Studies 4 and 5). (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Abnormal Brain Activation During Theory of Mind Tasks in Schizophrenia: A Meta-Analysis.

PubMed

Kronbichler, Lisa; Tschernegg, Melanie; Martin, Anna Isabel; Schurz, Matthias; Kronbichler, Martin

2017-10-21

Social cognition abilities are severely impaired in schizophrenia (SZ). The current meta-analysis used foci of 21 individual studies on functional abnormalities in the schizophrenic brain in order to identify regions that reveal convergent under- or over-activation during theory of mind (TOM) tasks. Studies were included in the analyses when contrasting tasks that require the processing of mental states with tasks which did not. Only studies that investigated patients with an ICD or DSM diagnosis were included. Quantitative voxel-based meta-analyses were done using Seed-based d Mapping software. Common TOM regions like medial-prefrontal cortex and temporo-parietal junction revealed abnormal activation in schizophrenic patients: Under-activation was identified in the medial prefrontal cortex, left orbito-frontal cortex, and in a small section of the left posterior temporo-parietal junction. Remarkably, robust over-activation was identified in a more dorsal, bilateral section of the temporo-parietal junction. Further abnormal activation was identified in medial occipito-parietal cortex, right premotor areas, left cingulate gyrus, and lingual gyrus. The findings of this study suggest that SZ patients simultaneously show over- and under-activation in TOM-related regions. Especially interesting, temporo-parietal junction reveals diverging activation patterns with an under-activating left posterior and an over-activating bilateral dorsal section. In conclusion, SZ patients show less specialized brain activation in regions linked to TOM and increased activation in attention-related networks suggesting compensatory effects. © The Author 2017. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.

Investigation of crew performance in a multi-vehicle supervisory control task

NASA Technical Reports Server (NTRS)

Miller, R. A.; Plamondon, B. D.; Jagacinski, R. J.; Kirlik, A. C.

1986-01-01

Crew information processing and decision making in a supervisory control task which is loosely based on the mission of future generation helicopters is measured and represented. Subjects control the motion and activities of their own vehicle and direct the activities of four additional craft. The task involves searching an uncertain environment for cargo and enemies, returning cargo to home base and destroying enemies while attempting to avoid destruction of the scout and the supervised vehicles. A series of experiments with two-person crews and one-person crews were performed. Resulting crew performance was modeled with the objective of describing and understanding the information processing strategies utilized. Of particular interest are problem simplification strategies under time stress and high work load, simplification and compensation in the one-person cases, crew coordination in the two-person cases, and the relationship between strategy and errors in all cases. The results should provide some insight into the effective use of aids, particularly aids based on artificial intelligence, for similar tasks. The simulation is described which is used for the study and some preliminary results from the first two-person crew study are discussed.

Simultaneous fNIRS and thermal infrared imaging during cognitive task reveal autonomic correlates of prefrontal cortex activity

NASA Astrophysics Data System (ADS)

Pinti, Paola; Cardone, Daniela; Merla, Arcangelo

2015-12-01

Functional Near Infrared-Spectroscopy (fNIRS) represents a powerful tool to non-invasively study task-evoked brain activity. fNIRS assessment of cortical activity may suffer for contamination by physiological noises of different origin (e.g. heart beat, respiration, blood pressure, skin blood flow), both task-evoked and spontaneous. Spontaneous changes occur at different time scales and, even if they are not directly elicited by tasks, their amplitude may result task-modulated. In this study, concentration changes of hemoglobin were recorded over the prefrontal cortex while simultaneously recording the facial temperature variations of the participants through functional infrared thermal (fIR) imaging. fIR imaging provides touch-less estimation of the thermal expression of peripheral autonomic. Wavelet analysis revealed task-modulation of the very low frequency (VLF) components of both fNIRS and fIR signals and strong coherence between them. Our results indicate that subjective cognitive and autonomic activities are intimately linked and that the VLF component of the fNIRS signal is affected by the autonomic activity elicited by the cognitive task. Moreover, we showed that task-modulated changes in vascular tone occur both at a superficial and at larger depth in the brain. Combined use of fNIRS and fIR imaging can effectively quantify the impact of VLF autonomic activity on the fNIRS signals.

Avoiding sports-related sudden cardiac death in children with congenital channelopathy : Recommendations for sports activities.

PubMed

Lang, C N; Steinfurt, J; Odening, K E

2017-04-01

For the past few years, children affected by an inherited channelopathy have been counseled to avoid (recreational) sports activities and all competitive sports so as to prevent exercise-induced arrhythmia and sudden cardiac death. An increased understanding of the pathophysiological mechanisms, better anti-arrhythmic strategies, and, in particular, more epidemiological data on exercise-induced arrhythmia in active athletes with channelopathies have changed the universal recommendation of "no sports," leading to revised, less strict, and more differentiated guidelines (published by the American Heart Association/American College of Cardiology in 2015). In this review, we outline the disease- and genotype-specific mechanisms of exercise-induced arrhythmia; give an overview of trigger-, symptom-, and genotype-dependent guidance in sports activities for children with long QT syndrome (LQTS), Brugada syndrome (BrS), catecholaminergic polymorphic ventricular tachycardia (CPVT), or short QT syndrome (SQTS); and highlight the novelties in the current guidelines compared with previous versions. While it is still recommended for patients with LQT1 and CPVT (even when asymptomatic) and all symptomatic LQTS patients (independent of genotype) to avoid any competitive and high-intensity sports, other LQTS patients successfully treated with anti-arrhythmic therapies and phenotype-negative genotype-positive patients may be allowed to perform sports at different activity levels - provided they undergo regular, sophisticated evaluations to detect any changes in arrhythmogenic risk.

The contribution of coping related variables and cardiac vagal activity on the performance of a dart throwing task under pressure.

PubMed

Mosley, Emma; Laborde, Sylvain; Kavanagh, Emma

2017-10-01

The aims of this study were 1) to assess the predictive role of coping related variables (CRV) on cardiac vagal activity (derived from heart rate variability), and 2) to investigate the influence of CRV (including cardiac vagal activity) on a dart throwing task under low pressure (LP) and high pressure (HP) conditions. Participants (n=51) completed trait CRV questionnaires: Decision Specific Reinvestment Scale, Movement Specific Reinvestment Scale and Trait Emotional Intelligence Questionnaire. They competed in a dart throwing task under LP and HP conditions. Cardiac vagal activity measurements were taken at resting, task and during recovery for 5min. Self-reported ratings of stress were recorded at three time points via a visual analogue scale. Upon completion of the task, self-report measures of motivation, stress appraisal, attention, perceived pressure and dart throwing experience were completed. Results indicated that resting cardiac vagal activity had no predictors. Task cardiac vagal activity was predicted by resting cardiac vagal activity in both pressure conditions with the addition of a trait CRV in HP. Post task cardiac vagal activity was predicted by resting cardiac vagal activity in both conditions with the addition of a trait CRV in HP. Cardiac vagal reactivity (difference from resting to task) was predicted by a trait CRV in HP conditions. Cardiac vagal recovery (difference from task to post task) was predicted by a state CRV only in LP. Dart throwing task performance was predicted by a combination of both CRV and cardiac vagal activity. The current research suggests that coping related variables and cardiac vagal activity influence dart throwing task performance differently dependent on pressure condition. Copyright © 2017 Elsevier Inc. All rights reserved.

Age-related increase in brain activity during task-related and -negative networks and numerical inductive reasoning.

PubMed

Sun, Li; Liang, Peipeng; Jia, Xiuqin; Qi, Zhigang; Li, Kuncheng

2014-01-01

Recent neuroimaging studies have shown that elderly adults exhibit increased and decreased activation on various cognitive tasks, yet little is known about age-related changes in inductive reasoning. To investigate the neural basis for the aging effect on inductive reasoning, 15 young and 15 elderly subjects performed numerical inductive reasoning while in a magnetic resonance (MR) scanner. Functional magnetic resonance imaging (fMRI) analysis revealed that numerical inductive reasoning, relative to rest, yielded multiple frontal, temporal, parietal, and some subcortical area activations for both age groups. In addition, the younger participants showed significant regions of task-induced deactivation, while no deactivation occurred in the elderly adults. Direct group comparisons showed that elderly adults exhibited greater activity in regions of task-related activation and areas showing task-induced deactivation (TID) in the younger group. Our findings suggest an age-related deficiency in neural function and resource allocation during inductive reasoning.

PFC Activity Pattern During Verbal WM Task in Healthy Male and Female Subjects: A NIRS Study.

PubMed

Gao, Chenyang; Zhang, Lei; Luo, Dewu; Liu, Dan; Gong, Hui

2016-01-01

Near-infrared spectroscopy (NIRS), as a non-invasive optical imaging method, has been widely used in psychology research. Working memory (WM) is an extensively researched psychological concept related to the temporary storage and processing of information. Many neuropsychological studies demonstrate that several brain areas of prefrontal cortex (PFC) are engaged during verbal WM tasks. The gender-based differences in WM remains under dispute. To better understand the active module and gender differences in PFC activity patterns during verbal WM tasks, we investigated the blood oxygenation changes of the PFC in 15 healthy subjects using a homemade multichannel continuous-wave NIRS instrument, while performing a verbal n-back task. We employed traditional activation and novel connectivity analyses simultaneously. Males had a higher level of oxygenation activity and connectivity in PFC than females. Only the results of females revealed a leftward lateralization in the 2-back task.

Neuronal activity in primate auditory cortex during the performance of audiovisual tasks.

PubMed

Brosch, Michael; Selezneva, Elena; Scheich, Henning

2015-03-01

This study aimed at a deeper understanding of which cognitive and motivational aspects of tasks affect auditory cortical activity. To this end we trained two macaque monkeys to perform two different tasks on the same audiovisual stimulus and to do this with two different sizes of water rewards. The monkeys had to touch a bar after a tone had been turned on together with an LED, and to hold the bar until either the tone (auditory task) or the LED (visual task) was turned off. In 399 multiunits recorded from core fields of auditory cortex we confirmed that during task engagement neurons responded to auditory and non-auditory stimuli that were task-relevant, such as light and water. We also confirmed that firing rates slowly increased or decreased for several seconds during various phases of the tasks. Responses to non-auditory stimuli and slow firing changes were observed during both the auditory and the visual task, with some differences between them. There was also a weak task-dependent modulation of the responses to auditory stimuli. In contrast to these cognitive aspects, motivational aspects of the tasks were not reflected in the firing, except during delivery of the water reward. In conclusion, the present study supports our previous proposal that there are two response types in the auditory cortex that represent the timing and the type of auditory and non-auditory elements of a auditory tasks as well the association between elements. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Sympathetic nervous system activity measured by skin conductance quantifies the challenge of walking adaptability tasks after stroke.

PubMed

Clark, David J; Chatterjee, Sudeshna A; McGuirk, Theresa E; Porges, Eric C; Fox, Emily J; Balasubramanian, Chitralakshmi K

2018-02-01

Walking adaptability tasks are challenging for people with motor impairments. The construct of perceived challenge is typically measured by self-report assessments, which are susceptible to subjective measurement error. The development of an objective physiologically-based measure of challenge may help to improve the ability to assess this important aspect of mobility function. The objective of this study to investigate the use of sympathetic nervous system (SNS) activity measured by skin conductance to gauge the physiological stress response to challenging walking adaptability tasks in people post-stroke. Thirty adults with chronic post-stroke hemiparesis performed a battery of seventeen walking adaptability tasks. SNS activity was measured by skin conductance from the palmar surface of each hand. The primary outcome variable was the percent change in skin conductance level (ΔSCL) between the baseline resting and walking phases of each task. Task difficulty was measured by performance speed and by physical therapist scoring of performance. Walking function and balance confidence were measured by preferred walking speed and the Activities-specific Balance Confidence Scale, respectively. There was a statistically significant negative association between ΔSCL and task performance speed and between ΔSCL and clinical score, indicating that tasks with greater SNS activity had slower performance speed and poorer clinical scores. ΔSCL was significantly greater for low functioning participants versus high functioning participants, particularly during the most challenging walking adaptability tasks. This study supports the use of SNS activity measured by skin conductance as a valuable approach for objectively quantifying the perceived challenge of walking adaptability tasks in people post-stroke. Published by Elsevier B.V.

Sympathetic nervous system activity measured by skin conductance quantifies the challenge of walking adaptability tasks after stroke

PubMed Central

Clark, David J.; Chatterjee, Sudeshna A.; McGuirk, Theresa E.; Porges, Eric C.; Fox, Emily J.; Balasubramanian, Chitralakshmi K.

2018-01-01

Background Walking adaptability tasks are challenging for people with motor impairments. The construct of perceived challenge is typically measured by self-report assessments, which are susceptible to subjective measurement error. The development of an objective physiologically-based measure of challenge may help to improve the ability to assess this important aspect of mobility function. The objective of this study to investigate the use of sympathetic nervous system (SNS) activity measured by skin conductance to gauge the physiological stress response to challenging walking adaptability tasks in people post-stroke. Methods Thirty adults with chronic post-stroke hemiparesis performed a battery of seventeen walking adaptability tasks. SNS activity was measured by skin conductance from the palmar surface of each hand. The primary outcome variable was the percent change in skin conductance level (ΔSCL) between the baseline resting and walking phases of each task. Task difficulty was measured by performance speed and by physical therapist grading of performance. Walking function and balance confidence were measured by preferred walking speed and the Activities Specific Balance Confidence Scale, respectively. Results There was a statistically significant negative association between ΔSCL and task performance speed and between ΔSCL and clinical score, indicating that tasks with greater SNS activity had slower performance speed and poorer clinical scores. ΔSCL was significantly greater for low functioning participants versus high functioning participants, particularly during the most challenging walking adaptability tasks. Conclusion This study supports the use of SNS activity measured by skin conductance as a valuable approach for objectively quantifying the perceived challenge of walking adaptability tasks in people post-stroke. PMID:29216598

Escape from harm: linking affective vision and motor responses during active avoidance

PubMed Central

Keil, Andreas

2014-01-01

When organisms confront unpleasant objects in their natural environments, they engage in behaviors that allow them to avoid aversive outcomes. Here, we linked visual processing of threat to its behavioral consequences by including a motor response that terminated exposure to an aversive event. Dense-array steady-state visual evoked potentials were recorded in response to conditioned threat and safety signals viewed in active or passive behavioral contexts. The amplitude of neuronal responses in visual cortex increased additively, as a function of emotional value and action relevance. The gain in local cortical population activity for threat relative to safety cues persisted when aversive reinforcement was behaviorally terminated, suggesting a lingering emotionally based response amplification within the visual system. Distinct patterns of long-range neural synchrony emerged between the visual cortex and extravisual regions. Increased coupling between visual and higher-order structures was observed specifically during active perception of threat, consistent with a reorganization of neuronal populations involved in linking sensory processing to action preparation. PMID:24493849

Differences in Spontaneously Avoiding or Approaching Mice Reflect Differences in CB1-Mediated Signaling of Dorsal Striatal Transmission

PubMed Central

Laricchiuta, Daniela; Rossi, Silvia; Musella, Alessandra; De Chiara, Valentina; Cutuli, Debora; Centonze, Diego; Petrosini, Laura

2012-01-01

Approach or avoidance behaviors are accompanied by perceptual vigilance for, affective reactivity to and behavioral predisposition towards rewarding or punitive stimuli, respectively. We detected three subpopulations of C57BL/6J mice that responded with avoiding, balancing or approaching behaviors not induced by any experimental manipulation but spontaneously displayed in an approach/avoidance conflict task. Although the detailed neuronal mechanisms underlying the balancing between approach and avoidance are not fully clarified, there is growing evidence that endocannabinoid system (ECS) plays a critical role in the control of these balancing actions. The sensitivity of dorsal striatal synapses to the activation of cannabinoid CB1 receptors was investigated in the subpopulations of spontaneously avoiding, balancing or approaching mice. Avoiding animals displayed decreased control of CB1 receptors on GABAergic striatal transmission and in parallel increase of behavioral inhibition. Conversely, approaching animals exhibited increased control of CB1 receptors and in parallel increase of explorative behavior. Balancing animals reacted with balanced responses between approach and avoidance patterns. Treating avoiding animals with URB597 (fatty acid amide hydrolase inhibitor) or approaching animals with AM251 (CB1 receptor inverse agonist) reverted their respective behavioral and electrophysiological patterns. Therefore, enhanced or reduced CB1-mediated control on dorsal striatal transmission represents the synaptic hallmark of the approach or avoidance behavior, respectively. Thus, the opposite spontaneous responses to conflicting stimuli are modulated by a different involvement of endocannabinoid signaling of dorsal striatal neurons in the range of temperamental traits related to individual differences. PMID:22413007

Hit or Run: Exploring Aggressive and Avoidant Reactions to Interpersonal Provocation Using a Novel Fight-or-Escape Paradigm (FOE).

PubMed

Beyer, Frederike; Buades-Rotger, Macià; Claes, Marie; Krämer, Ulrike M

2017-01-01

Interpersonal provocation presents an approach-avoidance conflict to the provoked person: responding aggressively might yield the joy of retribution, whereas withdrawal can provide safety. Experimental aggression studies typically measure only retaliation intensity, neglecting whether individuals want to confront the provocateur at all. To overcome this shortcoming of previous measures, we developed and validated the Fight-or-Escape paradigm (FOE). The FOE is a competitive reaction time (RT) task in which the winner can choose the volume of a sound blast to be directed at his/her opponent. Participants face two ostensible opponents who consistently select either high or low punishments. At the beginning of each trial, subjects are given the chance to avoid the encounter for a limited number of times. In a first experiment ( n = 27, all women), we found that fear potentiation (FP) of the startle response was related to lower scores in a composite measure of aggression and avoidance against the provoking opponent. In a second experiment ( n = 34, 13 men), we altered the paradigm such that participants faced the opponents in alternating rather than in random order. Participants completed the FOE as well as the Dot-Probe Task (DPT) and the Approach-Avoidance Task (AAT). Subjects with higher approach bias scores in the AAT avoided the provoking opponent less frequently. Hence, individuals with high threat reactivity and low approach motivation displayed more avoidant responses to provocation, whereas participants high in approach motivation were more likely to engage in aggressive interactions when provoked. The FOE is thus a promising laboratory measure of avoidance and aggression.

Hit or Run: Exploring Aggressive and Avoidant Reactions to Interpersonal Provocation Using a Novel Fight-or-Escape Paradigm (FOE)

PubMed Central

Beyer, Frederike; Buades-Rotger, Macià; Claes, Marie; Krämer, Ulrike M.

2017-01-01

Interpersonal provocation presents an approach-avoidance conflict to the provoked person: responding aggressively might yield the joy of retribution, whereas withdrawal can provide safety. Experimental aggression studies typically measure only retaliation intensity, neglecting whether individuals want to confront the provocateur at all. To overcome this shortcoming of previous measures, we developed and validated the Fight-or-Escape paradigm (FOE). The FOE is a competitive reaction time (RT) task in which the winner can choose the volume of a sound blast to be directed at his/her opponent. Participants face two ostensible opponents who consistently select either high or low punishments. At the beginning of each trial, subjects are given the chance to avoid the encounter for a limited number of times. In a first experiment (n = 27, all women), we found that fear potentiation (FP) of the startle response was related to lower scores in a composite measure of aggression and avoidance against the provoking opponent. In a second experiment (n = 34, 13 men), we altered the paradigm such that participants faced the opponents in alternating rather than in random order. Participants completed the FOE as well as the Dot-Probe Task (DPT) and the Approach-Avoidance Task (AAT). Subjects with higher approach bias scores in the AAT avoided the provoking opponent less frequently. Hence, individuals with high threat reactivity and low approach motivation displayed more avoidant responses to provocation, whereas participants high in approach motivation were more likely to engage in aggressive interactions when provoked. The FOE is thus a promising laboratory measure of avoidance and aggression. PMID:29089875

Effects of reaction time variability and age on brain activity during Stroop task performance.

PubMed

Tam, Angela; Luedke, Angela C; Walsh, Jeremy J; Fernandez-Ruiz, Juan; Garcia, Angeles

2015-09-01

Variability in reaction time during task performance may reflect fluctuations in attention and cause reduced performance in goal-directed tasks, yet it is unclear whether the mechanisms behind this phenomenon change with age. Using fMRI, we tested young and cognitively healthy older adults with the Stroop task to determine whether aging affects the neural mechanisms underlying intra-individual reaction time variability. We found significant between-group differences in BOLD activity modulated by reaction time. In older adults, longer reaction times were associated with greater activity in frontoparietal attentional areas, while in younger adults longer reaction times were associated with greater activity in default mode network areas. Our results suggest that the neural correlates of reaction time variability change with healthy aging, reinforcing the concept of functional plasticity to maintain high cognitive function throughout the lifespan.

Advanced obstacle avoidance for a laser based wheelchair using optimised Bayesian neural networks.

PubMed

Trieu, Hoang T; Nguyen, Hung T; Willey, Keith

2008-01-01

In this paper we present an advanced method of obstacle avoidance for a laser based intelligent wheelchair using optimized Bayesian neural networks. Three neural networks are designed for three separate sub-tasks: passing through a door way, corridor and wall following and general obstacle avoidance. The accurate usable accessible space is determined by including the actual wheelchair dimensions in a real-time map used as inputs to each networks. Data acquisitions are performed separately to collect the patterns required for specified sub-tasks. Bayesian frame work is used to determine the optimal neural network structure in each case. Then these networks are trained under the supervision of Bayesian rule. Experiment results showed that compare to the VFH algorithm our neural networks navigated a smoother path following a near optimum trajectory.

Memory-driven attentional capture reveals the waxing and waning of working memory activation due to dual-task interference.

PubMed

Sasin, Edyta; Nieuwenstein, Mark

2016-12-01

Previous studies have shown that information held in working memory (WM) actively or as a residue of previous processing can lead to attentional capture by corresponding stimuli in the environment. Here, we compared attentional capture by goal-driven and residual WM activation and examined how these effects are affected by dual-task interference. In two experiments, participants performed an animacy judgment task for a word that they did or did not have to remember for a later recognition test. The word was followed in half of the trials by an arithmetic task that served to disrupt the WM activation of the previously processed word. Subsequently, WM-driven capture was assessed by having participants perform a single-target rapid serial visual presentation task in which a line drawing corresponding to the word was presented shortly before a target. The results showed that the line drawing captured attention irrespective of the presence of the arithmetic task when the word had to be remembered. In comparison, the animacy judgment alone resulted in capture only when the arithmetic task was absent, and this effect was equally strong as the capture effect caused by a to-be-remembered word. Taken together, these findings show that although residual and goal-driven WM activation may be equally potent in guiding attentional selection, these two forms of WM activation differ in that residual activation is overwritten by an attention-demanding task, whereas goal-driven WM activation can lead to the reinstatement of a stimulus after performing such a task.

Modeling Avoidance in Mood and Anxiety Disorders Using Reinforcement Learning.

PubMed

Mkrtchian, Anahit; Aylward, Jessica; Dayan, Peter; Roiser, Jonathan P; Robinson, Oliver J

2017-10-01

Serious and debilitating symptoms of anxiety are the most common mental health problem worldwide, accounting for around 5% of all adult years lived with disability in the developed world. Avoidance behavior-avoiding social situations for fear of embarrassment, for instance-is a core feature of such anxiety. However, as for many other psychiatric symptoms the biological mechanisms underlying avoidance remain unclear. Reinforcement learning models provide formal and testable characterizations of the mechanisms of decision making; here, we examine avoidance in these terms. A total of 101 healthy participants and individuals with mood and anxiety disorders completed an approach-avoidance go/no-go task under stress induced by threat of unpredictable shock. We show an increased reliance in the mood and anxiety group on a parameter of our reinforcement learning model that characterizes a prepotent (pavlovian) bias to withhold responding in the face of negative outcomes. This was particularly the case when the mood and anxiety group was under stress. This formal description of avoidance within the reinforcement learning framework provides a new means of linking clinical symptoms with biophysically plausible models of neural circuitry and, as such, takes us closer to a mechanistic understanding of mood and anxiety disorders. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

A Cross-Cultural Investigation into How Tasks Influence Seatwork Activities in Mathematics Lessons

ERIC Educational Resources Information Center

Serrano, Ana M.

2012-01-01

This study examined how types of tasks influenced student activities/thinking and defined the role of Seatwork in mathematics lessons. It used 60 lessons from the TIMSS videotaped Study. These data indicated that practice was the most prevalent form of tasks in the U.S. In Germany, students completed mathematical calculations after a complex…

Physiological Aging Influence on Brain Hemodynamic Activity during Task-Switching: A fNIRS Study.

PubMed

Vasta, Roberta; Cutini, Simone; Cerasa, Antonio; Gramigna, Vera; Olivadese, Giuseppe; Arabia, Gennarina; Quattrone, Aldo

2017-01-01

Task-switching (TS) paradigm is a well-known validated tool useful for exploring the neural substrates of cognitive control, in particular the activity of the lateral and medial prefrontal cortex. This work is aimed at investigating how physiological aging influences hemodynamic response during the execution of a color-shape TS paradigm. A multi-channel near infrared spectroscopy (fNIRS) was used to measure hemodynamic activity in 27 young (30.00 ± 7.90 years) and 11 elderly participants (57.18 ± 9.29 years) healthy volunteers (55% male, age range: (19-69) years) during the execution of a TS paradigm. Two holders were placed symmetrically over the left/right hemispheres to record cortical activity [oxy-(HbO) and deoxy-hemoglobin (HbR) concentration] of the dorso-lateral prefrontal cortex (DLPFC), the dorsal premotor cortex (PMC), and the dorso-medial part of the superior frontal gyrus (sFG). TS paradigm requires participants to repeat the same task over a variable number of trials, and then to switch to a different task during the trial sequence. A two-sample t -test was carried out to detect differences in cortical responses between groups. Multiple linear regression analysis was used to evaluate the impact of age on the prefrontal neural activity. Elderly participants were significantly slower than young participants in both color- ( p < 0.01, t = -3.67) and shape-single tasks ( p = 0.026, t = -2.54) as well as switching ( p = 0.026, t = -2.41) and repetition trials ( p = 0.012, t = -2.80). Differences in cortical activation between groups were revealed for HbO mean concentration of switching task in the PMC ( p = 0.048, t = 2.94). In the whole group, significant increases of behavioral performance were detected in switching trials, which positively correlated with aging. Multivariate regression analysis revealed that the HbO mean concentration of switching task in the PMC ( p = 0.01, β = -0.321) and of shape single-task in the sFG ( p = 0.003, β = 0

Learning and memory deficits in mice lacking protease activated receptor-1

PubMed Central

Almonte, Antoine G.; Hamill, Cecily E.; Chhatwal, Jasmeer P.; Wingo, Thomas S.; Barber, Jeremy A.; Lyuboslavsky, Polina N.; Sweatt, J. David; Ressler, Kerry J.; White, David A.; Traynelis, Stephen F.

2007-01-01

The roles of serine proteases and protease activated receptors have been extensively studied in coagulation, wound healing, inflammation, and neurodegeneration. More recently, serine proteases have been suggested to influence synaptic plasticity. In this context, we examined the role of protease activated receptor 1 (PAR1), which is activated following proteolytic cleavage by thrombin and plasmin, in emotionally-motivated learning. We were particularly interested in PAR1 because its activation enhances the function of NMDA receptors, which are required for some forms of synaptic plasticity. We examined several baseline behavioral measures, including locomotor activity, expression of anxiety-like behavior, motor task acquisition, nociceptive responses, and startle responses in C57Bl/6 mice in which the PAR1 receptor has been genetically deleted. In addition, we evaluated learning and memory in these mice using two memory tasks, passive avoidance and cued fear-conditioning. Whereas locomotion, pain response, startle, and measures of baseline anxiety were largely unaffected by PAR1 removal, PAR1−/− animals showed significant deficits in a passive avoidance task and in cued fear conditioning. These data suggest that PAR1 may play an important role in emotionally-motivated learning. PMID:17544303

Finance Students' Experiences of Lecture-Based Active Learning Tasks

ERIC Educational Resources Information Center

McCullough, Kerry; Munro, Nicholas

2018-01-01

Consistent with current higher education concerns with student engagement and the student experience, this study explored third-year undergraduate Finance students' experiences of lecture-based active learning tasks. Finance students from the 2012 and 2014 cohorts from a South African university were invited to complete an anonymous questionnaire…

Age-related increase in brain activity during task-related and -negative networks and numerical inductive reasoning

PubMed Central

Sun, Li; Liang, Peipeng; Jia, Xiuqin; Qi, Zhigang; Li, Kuncheng

2014-01-01

Objective: Recent neuroimaging studies have shown that elderly adults exhibit increased and decreased activation on various cognitive tasks, yet little is known about age-related changes in inductive reasoning. Methods: To investigate the neural basis for the aging effect on inductive reasoning, 15 young and 15 elderly subjects performed numerical inductive reasoning while in a magnetic resonance (MR) scanner. Results: Functional magnetic resonance imaging (fMRI) analysis revealed that numerical inductive reasoning, relative to rest, yielded multiple frontal, temporal, parietal, and some subcortical area activations for both age groups. In addition, the younger participants showed significant regions of task-induced deactivation, while no deactivation occurred in the elderly adults. Direct group comparisons showed that elderly adults exhibited greater activity in regions of task-related activation and areas showing task-induced deactivation (TID) in the younger group. Conclusions: Our findings suggest an age-related deficiency in neural function and resource allocation during inductive reasoning. PMID:25337240

Implicit Associations with Popularity in Early Adolescence: An Approach-Avoidance Analysis

ERIC Educational Resources Information Center

Lansu, Tessa A. M.; Cillessen, Antonius H. N.; Karremans, Johan C.

2012-01-01

This study examined 241 early adolescents' implicit and explicit associations with popularity. The peer status and gender of both the targets and the perceivers were considered. Explicit associations with popularity were assessed with sociometric methods. Implicit associations with popularity were assessed with an approach-avoidance task (AAT).…

Acute ethanol does not always affect delay discounting in rats selected to prefer or avoid ethanol.

PubMed

Wilhelm, Clare J; Mitchell, Suzanne H

2012-01-01

The purpose of this study was to determine whether animals predisposed to prefer alcohol possess an altered acute response to alcohol on a delay discounting task relative to animals predisposed to avoid alcohol. We used rats selected to prefer or avoid alcohol to assess whether genotype moderates changes in delay discounting induced by acute ethanol exposure. Selectively bred rat lines of Sardinian alcohol-preferring (sP; n = 8) and non-preferring (sNP; n = 8) rats, and alko alcohol (AA, n = 8) and alko non-alcohol (ANA, n = 8) rats were trained in an adjusting amount task to assess delay discounting. There were no significant effects of line on baseline discounting; however, both lines of alcohol-preferring rats exhibit slowed reaction times. Acute ethanol (0, 0.25, 0.5 g/kg) treatment also had no effect on delay discounting in any of the selectively bred rat lines. Our data indicate that in these lines of animals, alcohol preference or avoidance has no impact on delay discounting following acute ethanol exposure. It is possible that other genetic models or lines may be differentially affected by alcohol and exhibit qualitatively and quantitatively different responses in delay discounting tasks.

Vision-Based UAV Flight Control and Obstacle Avoidance

DTIC Science & Technology

2006-01-01

denoted it by Vb = (Vb1, Vb2 , Vb3). Fig. 2 shows the block diagram of the proposed vision-based motion analysis and obstacle avoidance system. We denote...structure analysis often involve computation- intensive computer vision tasks, such as feature extraction and geometric modeling. Computation-intensive...First, we extract a set of features from each block. 2) Second, we compute the distance between these two sets of features. In conventional motion

Automatic intersection map generation task 10 report.

DOT National Transportation Integrated Search

2016-02-29

This report describes the work conducted in Task 10 of the V2I Safety Applications Development Project. The work was performed by the University of Michigan Transportation Research Institute (UMTRI) under contract to the Crash Avoidance Metrics Partn...

β-Amyloid Deposition Is Associated with Decreased Right Prefrontal Activation during Task Switching among Cognitively Normal Elderly

PubMed Central

Steffener, Jason; Razlighi, Qolamreza R.; Habeck, Christian; Stern, Yaakov

2016-01-01

The accumulation of β-amyloid (Aβ) peptides, a pathological hallmark of Alzheimer's disease (AD), has been associated with functional alterations, often in an episodic memory system with a particular emphasis on medial temporal lobe function. The topography of Aβ deposition, however, largely overlaps with frontoparietal control (FPC) regions implicated in cognitive control that has been shown to be impaired in early mild AD. To understand the neural mechanism underlying early changes in cognitive control with AD, we examined the impact of Aβ deposition on task-evoked FPC activation using functional magnetic resonance imaging (fMRI) in humans. Forty-three young and 62 cognitively normal older adults underwent an fMRI session during an executive contextual task in which task difficulty varied: single (either letter case or vowel/consonant judgment task) vs dual (switching between letter case and vowel/consonant decisions) task. Older subjects additionally completed 18F-florbetaben positron emission tomography scans and were classified as either amyloid positive (Aβ+) or negative (Aβ−). Consistent with previous reports, age-related increases in brain activity were found in FPC regions commonly identified across groups. For both task conditions, Aβ-related increases in brain activity were found compared with baseline activity. For higher cognitive control load, however, Aβ+ elderly showed reduced task-switching activation in the right inferior frontal cortex. Our findings suggest that with Aβ deposition, brain activation in the cognitive control region reaches a maximum with lower control demand and decreases with higher control demand, which may underlie early impairment in cognitive control with AD progression. SIGNIFICANCE STATEMENT The accumulation of β-amyloid (Aβ) peptides, a pathological hallmark of Alzheimer's disease, spatially overlaps with frontoparietal control (FPC) regions implicated in cognitive control, but the impact of Aβ deposition on

Obstacle stepping involves spinal anticipatory activity associated with quadrupedal limb coordination.

PubMed

Michel, J; van Hedel, H J A; Dietz, V

2008-04-01

Obstacle avoidance steps are associated with a facilitation of spinal reflexes in leg muscles. Here we have examined the involvement of both leg and arm muscles. Subjects walking with reduced vision on a treadmill were acoustically informed about an approaching obstacle and received feedback about task performance. Reflex responses evoked by tibial nerve stimulation were observed in all arm and leg muscles examined in this study. They were enhanced before the execution of obstacle avoidance compared with normal steps and showed an exponential adaptation in contralateral arm flexor muscles corresponding to the improvement of task performance. This enhancement was absent when the body was partially supported during the task. During the execution of obstacle steps, electromyographic activity in the arm muscles mimicked the preceding reflex behaviour with respect to enhancement and adaptation. Our results demonstrate an anticipatory quadrupedal limb coordination with an involvement of proximal arm muscles in the acquisition and performance of this precision locomotor task. This is presumably achieved by an up-regulated activity of coupled cervico-thoracal interneuronal circuits.

Brain Activations Related to Saccadic Response Conflict are not Sensitive to Time on Task.

PubMed

Beldzik, Ewa; Domagalik, Aleksandra; Oginska, Halszka; Marek, Tadeusz; Fafrowicz, Magdalena

2015-01-01

Establishing a role of the dorsal medial frontal cortex in the performance monitoring and cognitive control has been a challenge to neuroscientists for the past decade. In light of recent findings, the conflict monitoring hypothesis has been elaborated to an action-outcome predictor theory. One of the findings that led to this re-evaluation was the fMRI study in which conflict-related brain activity was investigated in terms of the so-called time on task effect, i.e., a linear increase of the BOLD signal with longer response times. The aim of this study was to investigate brain regions involved in the processing of saccadic response conflict and to account for the time on task effect. A modified spatial cueing task was implemented in the event-related fMRI study with oculomotor responses. The results revealed several brain regions which show higher activity for incongruent trials in comparison to the congruent ones, including pre-supplementary motor area together with the frontal and parietal regions. Further analysis accounting for the effect of response time provided evidence that these brain activations were not sensitive to time on task but reflected purely the congruency effect.

Absence of “Warm-Up” during Active Avoidance Learning in a Rat Model of Anxiety Vulnerability: Insights from Computational Modeling

PubMed Central

Myers, Catherine E.; Smith, Ian M.; Servatius, Richard J.; Beck, Kevin D.

2014-01-01

Avoidance behaviors, in which a learned response causes omission of an upcoming punisher, are a core feature of many psychiatric disorders. While reinforcement learning (RL) models have been widely used to study the development of appetitive behaviors, less attention has been paid to avoidance. Here, we present a RL model of lever-press avoidance learning in Sprague-Dawley (SD) rats and in the inbred Wistar Kyoto (WKY) rat, which has been proposed as a model of anxiety vulnerability. We focus on “warm-up,” transiently decreased avoidance responding at the start of a testing session, which is shown by SD but not WKY rats. We first show that a RL model can correctly simulate key aspects of acquisition, extinction, and warm-up in SD rats; we then show that WKY behavior can be simulated by altering three model parameters, which respectively govern the tendency to explore new behaviors vs. exploit previously reinforced ones, the tendency to repeat previous behaviors regardless of reinforcement, and the learning rate for predicting future outcomes. This suggests that several, dissociable mechanisms may contribute independently to strain differences in behavior. The model predicts that, if the “standard” inter-session interval is shortened from 48 to 24 h, SD rats (but not WKY) will continue to show warm-up; we confirm this prediction in an empirical study with SD and WKY rats. The model further predicts that SD rats will continue to show warm-up with inter-session intervals as short as a few minutes, while WKY rats will not show warm-up, even with inter-session intervals as long as a month. Together, the modeling and empirical data indicate that strain differences in warm-up are qualitative rather than just the result of differential sensitivity to task variables. Understanding the mechanisms that govern expression of warm-up behavior in avoidance may lead to better understanding of pathological avoidance, and potential pathways to modify these processes. PMID

Integrating obstacle avoidance, global path planning, visual cue detection, and landmark triangulation in a mobile robot

NASA Astrophysics Data System (ADS)

Kortenkamp, David; Huber, Marcus J.; Congdon, Clare B.; Huffman, Scott B.; Bidlack, Clint R.; Cohen, Charles J.; Koss, Frank V.; Raschke, Ulrich; Weymouth, Terry E.

1993-05-01

This paper describes the design and implementation of an integrated system for combining obstacle avoidance, path planning, landmark detection and position triangulation. Such an integrated system allows the robot to move from place to place in an environment, avoiding obstacles and planning its way out of traps, while maintaining its position and orientation using distinctive landmarks. The task the robot performs is to search a 22 m X 22 m arena for 10 distinctive objects, visiting each object in turn. This same task was recently performed by a dozen different robots at a competition in which the robot described in this paper finished first.

Assessing the influence of a passive, upper extremity exoskeletal vest for tasks requiring arm elevation: Part I - "Expected" effects on discomfort, shoulder muscle activity, and work task performance.

PubMed

Kim, Sunwook; Nussbaum, Maury A; Mokhlespour Esfahani, Mohammad Iman; Alemi, Mohammad Mehdi; Alabdulkarim, Saad; Rashedi, Ehsan

2018-03-07

Use of exoskeletal vests (designed to support overhead work) can be an effective intervention approach for tasks involving arm elevation, yet little is known on the potential beneficial impacts of their use on physical demands and task performance. This laboratory study (n = 12) evaluated the effects of a prototype exoskeletal vest during simulated repetitive overhead drilling and light assembly tasks. Anticipated or expected benefits were assessed, in terms of perceived discomfort, shoulder muscle activity, and task performance. Using the exoskeletal vest did not substantially influence perceived discomfort, but did decrease normalized shoulder muscle activity levels (e.g., ≤ 45% reduction in peak activity). Drilling task completion time decreased by nearly 20% with the vest, but the number of errors increased. Overall, exoskeletal vest use has the potential to be a new intervention for work requiring arm elevation; however, additional investigations are needed regarding potential unexpected or adverse influences (see Part II). Copyright © 2018 Elsevier Ltd. All rights reserved.

Teachers Avoiding Learners' Avoidance: Is It Possible?

ERIC Educational Resources Information Center

Tadayyon, Maedeh; Zarrinabadi, Nourollah; Ketabi, Saeed

2016-01-01

Dealing with learners who prefer to take the back seat and avoid classroom participation can be every teacher's nightmare. This lack of participation may cause teacher frustration, and possibly the only way to reduce this lack of participation is to access the concept of avoidance strategy. Avoidance strategy is the abandonment of a classroom task…

Brain activity across the development of automatic categorization: A comparison of categorization tasks using multi-voxel pattern analysis

PubMed Central

Soto, Fabian A.; Waldschmidt, Jennifer G.; Helie, Sebastien; Ashby, F. Gregory

2013-01-01

Previous evidence suggests that relatively separate neural networks underlie initial learning of rule-based and information-integration categorization tasks. With the development of automaticity, categorization behavior in both tasks becomes increasingly similar and exclusively related to activity in cortical regions. The present study uses multi-voxel pattern analysis to directly compare the development of automaticity in different categorization tasks. Each of three groups of participants received extensive training in a different categorization task: either an information-integration task, or one of two rule-based tasks. Four training sessions were performed inside an MRI scanner. Three different analyses were performed on the imaging data from a number of regions of interest (ROIs). The common patterns analysis had the goal of revealing ROIs with similar patterns of activation across tasks. The unique patterns analysis had the goal of revealing ROIs with dissimilar patterns of activation across tasks. The representational similarity analysis aimed at exploring (1) the similarity of category representations across ROIs and (2) how those patterns of similarities compared across tasks. The results showed that common patterns of activation were present in motor areas and basal ganglia early in training, but only in the former later on. Unique patterns were found in a variety of cortical and subcortical areas early in training, but they were dramatically reduced with training. Finally, patterns of representational similarity between brain regions became increasingly similar across tasks with the development of automaticity. PMID:23333700

ERP correlates of object recognition memory in Down syndrome: Do active and passive tasks measure the same thing?

PubMed

Van Hoogmoed, A H; Nadel, L; Spanò, G; Edgin, J O

2016-02-01

Event related potentials (ERPs) can help to determine the cognitive and neural processes underlying memory functions and are often used to study populations with severe memory impairment. In healthy adults, memory is typically assessed with active tasks, while in patient studies passive memory paradigms are generally used. In this study we examined whether active and passive continuous object recognition tasks measure the same underlying memory process in typically developing (TD) adults and in individuals with Down syndrome (DS), a population with known hippocampal impairment. We further explored how ERPs in these tasks relate to behavioral measures of memory. Data-driven analysis techniques revealed large differences in old-new effects in the active versus passive task in TD adults, but no difference between these tasks in DS. The group with DS required additional processing in the active task in comparison to the TD group in two ways. First, the old-new effect started 150 ms later. Second, more repetitions were required to show the old-new effect. In the group with DS, performance on a behavioral measure of object-location memory was related to ERP measures across both tasks. In total, our results suggest that active and passive ERP memory measures do not differ in DS and likely reflect the use of implicit memory, but not explicit processing, on both tasks. Our findings highlight the need for a greater understanding of the comparison between active and passive ERP paradigms before they are inferred to measure similar functions across populations (e.g., infants or intellectual disability). Copyright © 2016 Elsevier Ltd. All rights reserved.

Threat to Freedom and the Detrimental Effect of Avoidance Goal Frames: Reactance as a Mediating Variable

PubMed Central

Niesta Kayser, Daniela; Graupmann, Verena; Fryer, James W.; Frey, Dieter

2016-01-01

Two experiments examined how individuals respond to a restriction presented within an approach versus an avoidance frame. In Study 1, working on a problem-solving task, participants were initially free to choose their strategy, but for a second task were told to change their strategy. The message to change was embedded in either an approach or avoidance frame. When confronted with an avoidance compared to an approach frame, the participants’ reactance toward the request was greater and, in turn, led to impaired performance. The role of reactance as a response to threat to freedom was explicitly examined in Study 2, in which participants evaluated a potential change in policy affecting their program of study herein explicitly varying whether a restriction was present or absent and whether the message was embedded in an approach versus avoidance frame. When communicated with an avoidance frame and as a restriction, participants showed the highest resistance in terms of reactance, message agreement and evaluation of the communicator. The difference in agreement with the change was mediated by reactance only when a restriction was present. Overall, avoidance goal frames were associated with more resistance to change on different levels of experience (reactance, performance, and person perception). Reactance mediated the effect of goal frame on other outcomes only when a restriction was present. PMID:27242572

Non-Interfering Effects of Active Post-Encoding Tasks on Episodic Memory Consolidation in Humans.

PubMed

Varma, Samarth; Takashima, Atsuko; Krewinkel, Sander; van Kooten, Maaike; Fu, Lily; Medendorp, W Pieter; Kessels, Roy P C; Daselaar, Sander M

2017-01-01

So far, studies that investigated interference effects of post-learning processes on episodic memory consolidation in humans have used tasks involving only complex and meaningful information. Such tasks require reallocation of general or encoding-specific resources away from consolidation-relevant activities. The possibility that interference can be elicited using a task that heavily taxes our limited brain resources, but has low semantic and hippocampal related long-term memory processing demands, has never been tested. We address this question by investigating whether consolidation could persist in parallel with an active, encoding-irrelevant, minimally semantic task, regardless of its high resource demands for cognitive processing. We distinguish the impact of such a task on consolidation based on whether it engages resources that are: (1) general/executive, or (2) specific/overlapping with the encoding modality. Our experiments compared subsequent memory performance across two post-encoding consolidation periods: quiet wakeful rest and a cognitively demanding n-Back task. Across six different experiments (total N = 176), we carefully manipulated the design of the n-Back task to target general or specific resources engaged in the ongoing consolidation process. In contrast to previous studies that employed interference tasks involving conceptual stimuli and complex processing demands, we did not find any differences between n-Back and rest conditions on memory performance at delayed test, using both recall and recognition tests. Our results indicate that: (1) quiet, wakeful rest is not a necessary prerequisite for episodic memory consolidation; and (2) post-encoding cognitive engagement does not interfere with memory consolidation when task-performance has minimal semantic and hippocampally-based episodic memory processing demands. We discuss our findings with reference to resource and reactivation-led interference theories.

Effects of long-term voluntary exercise on learning and memory processes: dependency of the task and level of exercise.

PubMed

García-Capdevila, Sílvia; Portell-Cortés, Isabel; Torras-Garcia, Meritxell; Coll-Andreu, Margalida; Costa-Miserachs, David

2009-09-14

The effect of long-term voluntary exercise (running wheel) on anxiety-like behaviour (plus maze and open field) and learning and memory processes (object recognition and two-way active avoidance) was examined on Wistar rats. Because major individual differences in running wheel behaviour were observed, the data were analysed considering the exercising animals both as a whole and grouped according to the time spent in the running wheel (low, high, and very-high running). Although some variables related to anxiety-like behaviour seem to reflect an anxiogenic compatible effect, the view of the complete set of variables could be interpreted as an enhancement of defensive and risk assessment behaviours in exercised animals, without major differences depending on the exercise level. Effects on learning and memory processes were dependent on task and level of exercise. Two-way avoidance was not affected either in the acquisition or in the retention session, while the retention of object recognition task was affected. In this latter task, an enhancement in low running subjects and impairment in high and very-high running animals were observed.

Atypical Activation during the Embedded Figures Task as a Functional Magnetic Resonance Imaging Endophenotype of Autism

ERIC Educational Resources Information Center

Spencer, Michael D.; Holt, Rosemary J.; Chura, Lindsay R.; Calder, Andrew J.; Suckling, John; Bullmore, Edward T.; Baron-Cohen, Simon

2012-01-01

Atypical activation during the Embedded Figures Task has been demonstrated in autism, but has not been investigated in siblings or related to measures of clinical severity. We identified atypical activation during the Embedded Figures Task in participants with autism and unaffected siblings compared with control subjects in a number of temporal…

Cortical activity in fine-motor tasks in children with Developmental Coordination Disorder: A preliminary fNIRS study.

PubMed

Caçola, Priscila; Getchell, Nancy; Srinivasan, Dhivya; Alexandrakis, Georgios; Liu, Hanli

2018-04-01

Developmental Coordination Disorder (DCD) is as a neurodevelopmental condition characterized by poor motor proficiency, which impacts academic performance and activities of daily living. Several studies have determined that children with DCD activate different regions of the brain when performing motor skills in comparison to typically developing (TD) children. However, none have used Functional Near-Infrared Spectroscopy (fNIRS) to explore cortical activation in this population. With that, the goal of this preliminary study was to investigate cortical activation using fNIRS in six children with DCD and six TD children between ages of 8 and 12 years. Three fine-motor tasks were performed: Finger Tapping (FT), Curve Tracing (CT), and Paragraph Writing (PW). Tasks were presented in counterbalanced order and had a baseline of 30s. Cortical activity elicited during performance of the FT, CT, and PW tasks was measured by fNIRS, and activation areas within each group were statistically compared. Results indicated that participant groups used different focal activation areas as well as different neural networks to perform the tasks. These distinct patterns were also task-specific, with differences in the right Pre-Motor Cortex (Pre-MC) and Supplementary Motor Area (SMA) for CT, and the right Dorsolateral Prefrontal Cortex (DLPFC) and the right Pre-MC for the PW task. These results add to the body of research exploring neurological alterations in children with DCD, and establish the feasibility of using fNIRS technology with this population. Copyright © 2017 ISDN. Published by Elsevier Ltd. All rights reserved.

Comparable cortical activation with inferior performance in women during a novel cognitive inhibition task.

PubMed

Halari, R; Kumari, V

2005-03-07

Men are hypothesised to perform better than women at tasks requiring cognitive inhibition. The present study applied whole-brain functional magnetic resonance imaging to investigate the neural correlates of cognitive inhibition using a novel task, requiring detection of numbers decreasing in numerical order, in relation to sex. The study involved 19 young healthy subjects (9 men, 10 women). Behavioural sex differences favouring men were found on the inhibition, but not on the automatization (i.e. detection of numbers increasing in numerical order), condition of the task. Significant areas of activation associated with cognitive inhibition included the right inferior prefrontal and bilateral dorsolateral prefrontal cortices, left inferior and superior parietal lobes, and bilateral temporal regions across men and women. No brain region was significantly differently activated in men and women. Our findings demonstrate that (a) cognitive inhibition is dependent on intact processes within frontal and parietal regions, and (b) women show inferior cognitive inhibition despite of comparable activation to men in relevant regions. Equated behavioural performance may elicit sex differences in brain activation.

Avoidance of accelerated aging in schizophrenia?: Clinical and biological characterization of an exceptionally high functioning individual.

PubMed

Palmer, Barton W; Moore, Raeanne C; Eyler, Lisa T; Pinto, Luz L; Saks, Elyn R; Jeste, Dilip V

2018-06-01

To determine the clinical and biological characteristics of an exceptionally high functioning index person (IP) with schizophrenia in her mid-50s, which may represent compensatory mechanisms, and potentially, avoidance of the accelerated aging typically associated with schizophrenia. IP, 11 other women with schizophrenia, and 11 non-psychiatric comparison (NC) women were assessed with standard ratings of psychopathology, neurocognitive function, decisional capacity, and functional brain imaging. IP was also compared to a sample of demographically similar NCs (N=45) and persons with schizophrenia (N=42) on a set of blood-based biomarkers of aging related to metabolic function, oxidative stress, and inflammation. IP's scores on working memory, and levels of brain activation during an affective face matching task in the left fusiform, right lingual, and left precentral gyri, exceeded NCs. IP was similar to NCs in severity of negative symptoms, most neurocognitive functions, decisional capacity, and brain activation in the left inferior occipital gyrus during a selective stopping task. IP's levels on 11 of 14 metabolic and inflammatory biomarkers of aging were better than NCs and the schizophrenia group. Although speculative, results suggest a possible model in which superior working memory permits a person to be aware of the potentially psychotic nature of a thought or perception, and adjust response accordingly. Compensatory overactivity of brain regions during affective processing may also reflect heightened meta-awareness in emotional situations. Biomarker levels raise the possibility that IP partially avoided the accelerated biological aging associated with schizophrenia. Published by Elsevier B.V.

Brain Activation for Language Dual-Tasking: Listening to Two People Speak at the Same Time and a Change in Network Timing

PubMed Central

Buchweitz, Augusto; Keller, Timothy A.; Meyler, Ann; Just, Marcel Adam

2011-01-01

The study used fMRI to investigate brain activation in participants who were able to listen to and successfully comprehend two people speaking at the same time (dual-tasking). The study identified brain mechanisms associated with high-level, concurrent dual-tasking, as compared to comprehending a single message. Results showed an increase in the functional connectivity among areas of the language network in the dual task. The increase in synchronization of brain activation for dual-tasking was brought about primarily by a change in the timing of left inferior frontal gyrus (LIFG) activation relative to posterior temporal activation, bringing the LIFG activation into closer correspondence with temporal activation. The results show that the change in LIFG timing was greater in participants with lower working memory capacity, and that recruitment of additional activation in the dual-task occurred only in the areas adjacent to the language network that was activated in the single task. The shift in LIFG activation may be a brain marker of how the brain adapts to high-level dual-tasking. PMID:21618666

Brain activation for language dual-tasking: listening to two people speak at the same time and a change in network timing.

PubMed

Buchweitz, Augusto; Keller, Timothy A; Meyler, Ann; Just, Marcel Adam

2012-08-01

The study used fMRI to investigate brain activation in participants who were able to listen to and successfully comprehend two people speaking at the same time (dual-tasking). The study identified brain mechanisms associated with high-level, concurrent dual-tasking, as compared with comprehending a single message. Results showed an increase in the functional connectivity among areas of the language network in the dual task. The increase in synchronization of brain activation for dual-tasking was brought about primarily by a change in the timing of left inferior frontal gyrus (LIFG) activation relative to posterior temporal activation, bringing the LIFG activation into closer correspondence with temporal activation. The results show that the change in LIFG timing was greater in participants with lower working memory capacity, and that recruitment of additional activation in the dual-task occurred only in the areas adjacent to the language network that was activated in the single task. The shift in LIFG activation may be a brain marker of how the brain adapts to high-level dual-tasking. Copyright © 2011 Wiley Periodicals, Inc.

Physical activity during work and leisure show contrasting associations with fear-avoidance beliefs: cross-sectional study among more than 10,000 wage earners of the general working population.

PubMed

Tribian, Annika; Vinstrup, Jonas; Sundstrup, Emil; Jay, Kenneth; Bös, Klaus; Andersen, Lars L

2018-01-26

The association between different types of physical activity and fear-avoidance beliefs remains unclear. This study investigates the association between work-related and leisure-time physical activity with fear-avoidance beliefs in the general working population. Currently employed wage earners (n=10,427) from the 2010 round of the Danish Work Environment Cohort Study replied to questions about work, lifestyle and health. General linear models controlling for lifestyle, psychosocial work factors, education, pain, medication-use and chronic diseases tested associations of work-related and leisure-time physical activity (explanatory variables) with fear-avoidance beliefs (outcome variable, scale 0-100). The level of fear-avoidance was 41.7 (SD 27.3), 38.0 (SD 26.9) and 54.3 (SD 27.7) among the general working population, a subgroup of pain-free individuals, and a subgroup with back disease, respectively. In the general working population, the level of fear-avoidance among those with low, moderate and high physical activity during leisure were 47 [95% confidence intervals (CI) 45-49], 44 (95% CI 42-46) and 43 (95% CI 41-45), and physical activity at work were 40 (95% CI 39-42), 44 (95% CI 42-46) and 49 (95% CI 48-51), respectively. Individuals with back disease and a high level of physical activity at work showed the overall highest level of fear-avoidance whereas pain-free individuals with a low level of physical activity at work showed the overall lowest level of fear-avoidance. Physical activity during work and leisure shows contrasting associations with fear-avoidance beliefs. While high physical activity during leisure is associated with lower levels, high physical activity at work is associated with higher levels of fear-avoidance. The present results may reflect some deeply rooted negative beliefs about pain and work in the population. On the societal level, campaigns may be a possible way forward as these have shown to improve beliefs about musculoskeletal

Identifying Empirically Supported Treatments for Phobic Avoidance in Individuals with Intellectual Disabilities

ERIC Educational Resources Information Center

Jennett, Heather K.; Hagopian, Louis P.

2008-01-01

This paper reviews the literature regarding the treatment of phobic avoidance in individuals with intellectual disabilities. Criteria for classifying interventions as empirically supported, developed by the American Psychological Association (APA) Division 12 Task Force on Promotion and Dissemination of Psychological Procedures, were used. For…

Hippocampal activation during the recall of remote spatial memories in radial maze tasks.

PubMed

Schlesiger, Magdalene I; Cressey, John C; Boublil, Brittney; Koenig, Julie; Melvin, Neal R; Leutgeb, Jill K; Leutgeb, Stefan

2013-11-01

Temporally graded retrograde amnesia is observed in human patients with medial temporal lobe lesions as well as in animal models of medial temporal lobe lesions. A time-limited role for these structures in memory recall has also been suggested by the observation that the rodent hippocampus and entorhinal cortex are activated during the retrieval of recent but not of remote memories. One notable exception is the recall of remote memories for platform locations in the water maze, which requires an intact hippocampus and results in hippocampal activation irrespective of the age of the memory. These findings raise the question whether the hippocampus is always involved in the recall of spatial memories or, alternatively, whether it might be required for procedural computations in the water maze task, such as for calculating a path to a hidden platform. We performed spatial memory testing in radial maze tasks to distinguish between these possibilities. Radial maze tasks require a choice between spatial locations on a center platform and thus have a lesser requirement for navigation than the water maze. However, we used a behavioral design in the radial maze that retained other aspects of the standard water maze task, such as the use of multiple start locations and retention testing in a single trial. Using the immediate early gene c-fos as a marker for neuronal activation, we found that all hippocampal subregions were more activated during the recall of remote compared to recent spatial memories. In areas CA3 and CA1, activation during remote memory testing was higher than in rats that were merely reexposed to the testing environment after the same time interval. Conversely, Fos levels in the dentate gyrus were increased after retention testing to the extent that was also observed in the corresponding exposure control group. This pattern of hippocampal activation was also obtained in a second version of the task that only used a single start arm instead of multiple

Time stamp in conditioned place avoidance can be set to different circadian phases.

PubMed

Cain, Sean W; McDonald, Robert J; Ralph, Martin R

2008-05-01

We have reported that the expression of conditioned place avoidance (CPA) in the golden hamster is regulated in a circadian pattern such that the preference is exhibited strongly at the circadian time of prior training but not at other circadian times [Cain, S. W., Chou, T., & Ralph, M. R. (2004a). Circadian modulation of performance on an aversion-based place learning task in hamsters. Behavioural Brain Research, 150(1-2), 201-205]. In that study, animals that were trained at a specific circadian time to discriminate between a "safe" context and one paired with foot shock, showed strong avoidance of the paired context at 24 and 48h following the last training session, and showed no avoidance at 32 and 40h following training. In the present study, we hypothesized that this "time stamp" effect is settable to any circadian phase. This was tested by training animals at one of two times of day (ZT13 or ZT4) and testing whether a time stamp would be observed, with avoidance occurring only when training and testing times match. Results confirmed our hypothesis, suggesting that the time stamp in the performance of learned tasks can be set to any circadian phase. Such an ability may allow animals in nature to predict the recurrence of 24h events, regardless of the time of day the event was encountered.

Hierarchical Brain Networks Active in Approach and Avoidance Goal Pursuit

PubMed Central

Spielberg, Jeffrey M.; Heller, Wendy; Miller, Gregory A.

2013-01-01

Effective approach/avoidance goal pursuit is critical for attaining long-term health and well-being. Research on the neural correlates of key goal-pursuit processes (e.g., motivation) has long been of interest, with lateralization in prefrontal cortex being a particularly fruitful target of investigation. However, this literature has often been limited by a lack of spatial specificity and has not delineated the precise aspects of approach/avoidance motivation involved. Additionally, the relationships among brain regions (i.e., network connectivity) vital to goal-pursuit remain largely unexplored. Specificity in location, process, and network relationship is vital for moving beyond gross characterizations of function and identifying the precise cortical mechanisms involved in motivation. The present paper integrates research using more spatially specific methodologies (e.g., functional magnetic resonance imaging) with the rich psychological literature on approach/avoidance to propose an integrative network model that takes advantage of the strengths of each of these literatures. PMID:23785328

Hierarchical brain networks active in approach and avoidance goal pursuit.

PubMed

Spielberg, Jeffrey M; Heller, Wendy; Miller, Gregory A

2013-01-01

Effective approach/avoidance goal pursuit is critical for attaining long-term health and well-being. Research on the neural correlates of key goal-pursuit processes (e.g., motivation) has long been of interest, with lateralization in prefrontal cortex being a particularly fruitful target of investigation. However, this literature has often been limited by a lack of spatial specificity and has not delineated the precise aspects of approach/avoidance motivation involved. Additionally, the relationships among brain regions (i.e., network connectivity) vital to goal-pursuit remain largely unexplored. Specificity in location, process, and network relationship is vital for moving beyond gross characterizations of function and identifying the precise cortical mechanisms involved in motivation. The present paper integrates research using more spatially specific methodologies (e.g., functional magnetic resonance imaging) with the rich psychological literature on approach/avoidance to propose an integrative network model that takes advantage of the strengths of each of these literatures.

Attentional Flexibility During Approach and Avoidance Motivational States: The Role of Context in Shifts of Attentional Breadth

PubMed Central

Calcott, Rebecca D.; Berkman, Elliot T.

2014-01-01

In the present studies, we aimed to understand how approach and avoidance states affect attentional flexibility by examining attentional shifts on a trial-by-trial basis. We also examined how a novel construct in this area, task context, might interact with motivation to influence attentional flexibility. Participants completed a modified composite letter task in which the ratio of global to local targets was varied by block, making different levels of attentional focus beneficial to performance on different blocks. Study 1 demonstrated that, in the absence of a motivation manipulation, switch costs were lowest on blocks with an even ratio of global and local trials and were higher on blocks with an uneven ratio. Other participants completed the task while viewing pictures (Studies 2 and 3) and assuming arm positions (Studies 2 and 4) to induce approach, avoidance, and neutral motivational states. Avoidance motivation reduced switch costs in evenly proportioned contexts, whereas approach motivation reduced switch costs in mostly global contexts. Additionally, approach motivation imparted a similar switch cost magnitude across different contexts, whereas avoidance and neutral states led to variable switch costs depending on the context. Subsequent analyses revealed that these effects were driven largely by faster switching to local targets on mostly global blocks in the approach condition. These findings suggest that avoidance facilitates attentional shifts when switches are frequent, whereas approach facilitates responding to rare or unexpected local stimuli. The main implication of these results is that motivation has different effects on attentional shifts depending on the context. PMID:24294866

PWZ-029, A COMPOUND WITH MODERATE INVERSE AGONIST FUNCTIONAL SELECTIVITY AT GABAA RECEPTORS CONTAINING α5 SUBUNITS, IMPROVES PASSIVE, BUT NOT ACTIVE, AVOIDANCE LEARNING IN RATS