Visual impairment as an independent risk factor for falls in hospitalized patients.

PubMed

Kasuga, Toshimitsu; Aruga, Fumiko; Ono, Koichi; Hiratsuka, Yoshimune; Murakami, Akira

2017-12-01

To investigate the association between visual impairment and the risk of falls in hospitalized patients. Individually matched case-control study. The medical records of patients who fell while hospitalized at Juntendo Tokyo Koto Geriatric Medical Center (JTKGMC) from January to December 2014 were reviewed retrospectively. Among them, 36 patients who were recorded as visiting the Ophthalmology Outpatient Clinic from 1 year before to 1 year after the fall were included as cases. As the control subjects, 36 individually matched patients were chosen who were hospitalized in the same beds in the same hospital wards. Visual impairment and blindness were defined according to U.S. criteria. Conditional logistic regression analysis was used for both univariate and multivariate analyses. Based on previous reports, multivariate analysis was performed with adjustment for age, sex, a history of falls, and use of walking aids. This study was approved by the institutional review board of JTKGMC and was performed according to the tenets of the Declaration of Helsinki. The crude odds ratio (OR) for visual impairment was 6.0 (95% confidence interval [CI]: 0.72-49.83). For a history of falls and use of walking aids, the crude OR (95% CI) was 2.5 (0.97-6.44) and 2.8 (0.88-8.64), respectively. After adjustment for age, sex, a history of falls, and use of walking aids, the association between falls and visual impairment was significant (OR: 13.9; 95% CI: 1.0004-194.41). These findings suggest that visual impairment could be an independent risk factor for falls among hospitalized patients. Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

Postural Control in Young People with Visual Impairments and Various Risks of Falls

ERIC Educational Resources Information Center

Sadowska, Dorota; Stemplewski, Rafal; Szeklicki, Robert

2017-01-01

Introduction: Early diagnosis of postural control deficiencies facilitates implementation of an individual rehabilitation plan to prevent falls. The aim of the study was to assess the risk of falling in individuals with visual impairments, and to compare performance-based and theoretical limits of stability in subjects with various risks of…

Fear of falling and postural reactivity in patients with glaucoma.

PubMed

Daga, Fábio B; Diniz-Filho, Alberto; Boer, Erwin R; Gracitelli, Carolina P B; Abe, Ricardo Y; Medeiros, Felipe A

2017-01-01

To investigate the relationship between postural metrics obtained by dynamic visual stimulation in a virtual reality environment and the presence of fear of falling in glaucoma patients. This cross-sectional study included 35 glaucoma patients and 26 controls that underwent evaluation of postural balance by a force platform during presentation of static and dynamic visual stimuli with head-mounted goggles (Oculus Rift). In dynamic condition, a peripheral translational stimulus was used to induce vection and assess postural reactivity. Standard deviations of torque moments (SDTM) were calculated as indicative of postural stability. Fear of falling was assessed by a standardized questionnaire. The relationship between a summary score of fear of falling and postural metrics was investigated using linear regression models, adjusting for potentially confounding factors. Subjects with glaucoma reported greater fear of falling compared to controls (-0.21 vs. 0.27; P = 0.039). In glaucoma patients, postural metrics during dynamic visual stimulus were more associated with fear of falling (R2 = 18.8%; P = 0.001) than static (R2 = 3.0%; P = 0.005) and dark field (R2 = 5.7%; P = 0.007) conditions. In the univariable model, fear of falling was not significantly associated with binocular standard perimetry mean sensitivity (P = 0.855). In the multivariable model, each 1 Nm larger SDTM in anteroposterior direction during dynamic stimulus was associated with a worsening of 0.42 units in the fear of falling questionnaire score (P = 0.001). In glaucoma patients, postural reactivity to a dynamic visual stimulus using a virtual reality environment was more strongly associated with fear of falling than visual field testing and traditional balance assessment.

Fear of falling and postural reactivity in patients with glaucoma

PubMed Central

Daga, Fábio B.; Diniz-Filho, Alberto; Boer, Erwin R.; Gracitelli, Carolina P. B.; Abe, Ricardo Y.; Medeiros, Felipe A.

2017-01-01

Purpose To investigate the relationship between postural metrics obtained by dynamic visual stimulation in a virtual reality environment and the presence of fear of falling in glaucoma patients. Methods This cross-sectional study included 35 glaucoma patients and 26 controls that underwent evaluation of postural balance by a force platform during presentation of static and dynamic visual stimuli with head-mounted goggles (Oculus Rift). In dynamic condition, a peripheral translational stimulus was used to induce vection and assess postural reactivity. Standard deviations of torque moments (SDTM) were calculated as indicative of postural stability. Fear of falling was assessed by a standardized questionnaire. The relationship between a summary score of fear of falling and postural metrics was investigated using linear regression models, adjusting for potentially confounding factors. Results Subjects with glaucoma reported greater fear of falling compared to controls (-0.21 vs. 0.27; P = 0.039). In glaucoma patients, postural metrics during dynamic visual stimulus were more associated with fear of falling (R2 = 18.8%; P = 0.001) than static (R2 = 3.0%; P = 0.005) and dark field (R2 = 5.7%; P = 0.007) conditions. In the univariable model, fear of falling was not significantly associated with binocular standard perimetry mean sensitivity (P = 0.855). In the multivariable model, each 1 Nm larger SDTM in anteroposterior direction during dynamic stimulus was associated with a worsening of 0.42 units in the fear of falling questionnaire score (P = 0.001). Conclusion In glaucoma patients, postural reactivity to a dynamic visual stimulus using a virtual reality environment was more strongly associated with fear of falling than visual field testing and traditional balance assessment. PMID:29211742

Visual-somatosensory integration and balance: evidence for psychophysical integrative differences in aging.

PubMed

Mahoney, Jeannette R; Holtzer, Roee; Verghese, Joe

2014-01-01

Research detailing multisensory integration (MSI) processes in aging and their association with clinically relevant outcomes is virtually non-existent. To our knowledge, the relationship between MSI and balance has not been well-established in aging. Given known alterations in unisensory processing with increasing age, the aims of the current study were to determine differential behavioral patterns of MSI in aging and investigate whether MSI was significantly associated with balance and fall-risk. Seventy healthy older adults (M = 75 years; 58% female) participated in the current study. Participants were instructed to make speeded responses to visual, somatosensory, and visual-somatosensory (VS) stimuli. Based on reaction times (RTs) to all stimuli, participants were classified into one of two groups (MSI or NO MSI), depending on their MSI RT benefit. Static balance was assessed using mean unipedal stance time. Overall, results revealed that RTs to VS stimuli were significantly shorter than those elicited to constituent unisensory conditions. Further, the current experimental design afforded differential patterns of multisensory processing, with 75% of the elderly sample demonstrating multisensory enhancements. Interestingly, 25% of older adults did not demonstrate multisensory RT facilitation; a finding that was attributed to extremely fast RTs overall and specifically in response to somatosensory inputs. Individuals in the NO MSI group maintained significantly better unipedal stance times and reported less falls, compared to elders in the MSI group. This study reveals the existence of differential patterns of multisensory processing in aging, while describing the clinical translational value of MSI enhancements in predicting balance and falls risk.

Visual-Somatosensory Integration and Balance: Evidence for Psychophysical Integrative Differences in Aging

PubMed Central

Mahoney, Jeannette R.; Holtzer, Roee; Verghese, Joe

2014-01-01

Research detailing multisensory integration (MSI) processes in aging and their association with clinically relevant outcomes is virtually non-existent. To our knowledge, the relationship between MSI and balance has not been well-established in aging. Given known alterations in unisensory processing with increasing age, the aims of the current study were to determine differential behavioral patterns of MSI in aging and investigate whether MSI was significantly associated with balance and fall-risk. Seventy healthy older adults (M = 75 years; 58% female) participated in the current study. Participants were instructed to make speeded responses to visual, somatosensory, and visual-somatosensory (VS) stimuli. Based on reaction times (RTs) to all stimuli, participants were classified into one of two groups (MSI or NO MSI), depending on their MSI RT benefit. Static balance was assessed using mean unipedal stance time. Overall, results revealed that RTs to VS stimuli were significantly shorter than those elicited to constituent unisensory conditions. Further, the current experimental design afforded differential patterns of multisensory processing, with 75% of the elderly sample demonstrating multisensory enhancements. Interestingly, 25% of older adults did not demonstrate multisensory RT facilitation; a finding that was attributed to extremely fast RTs overall and specifically in response to somatosensory inputs. Individuals in the NO MSI group maintained significantly better unipedal stance times and reported less falls, compared to elders in the MSI group. This study reveals the existence of differential patterns of multisensory processing in aging, while describing the clinical translational value of MSI enhancements in predicting balance and falls risk. PMID:25102664

A systematic review and meta-analysis of exercise-based falls prevention strategies in adults aged 50+ years with visual impairment.

PubMed

Dillon, Lisa; Clemson, Lindy; Ramulu, Pradeep; Sherrington, Catherine; Keay, Lisa

2018-05-06

To determine the impact of exercise or physical training on falls or physical function in people aged 50+ years with visual impairment, compared with control (no intervention or usual care). An updated systematic review of randomised controlled trials, investigating the effect of exercise or physical activity on falls prevention or physical function in adults aged 50+ with visual impairment. Searches of CINAHL, the Cochrane Register of Controlled Trials (CENTRAL), Embase, and Medline were undertaken. Three trials were identified for the period February 2013 to July 2017 and added to the four in the original review. New trials evaluated yoga, the Otago Exercise Programme in combination with a home safety programme and the Alexander Technique. Meta-analysis of data from two trials (n = 163) indicated a non-statistically significant positive impact of exercise on the Chair Stand Test (WMD -1.85 s, 95% CI -4.65 to 0.96, p = 0.20, I 2 22%). In this update, two new trials measured falls so meta-analysis was possible for three trials (n = 539) and revealed no impact on falls (RR 1.05, 95% CI 0.73 to 1.50, p = 0.81, I 2 30%). Although exercise or physical training can improve physical function in older adults with visual impairment, and diverse strategies are being evaluated, there are no proven falls prevention strategies. In the few studies available, falls are not consistently reported and more work is required to investigate falls prevention in older adults with visual impairment. © 2018 The Authors Ophthalmic & Physiological Optics © 2018 The College of Optometrists.

The Rise and Fall of Priming: How Visual Exposure Shapes Cortical Representations of Objects

PubMed Central

Zago, Laure; Fenske, Mark J.; Aminoff, Elissa; Bar, Moshe

2006-01-01

How does the amount of time for which we see an object influence the nature and content of its cortical representation? To address this question, we varied the duration of initial exposure to visual objects and then measured functional magnetic resonance imaging (fMRI) signal and behavioral performance during a subsequent repeated presentation of these objects. We report a novel ‘rise-and-fall’ pattern relating exposure duration and the corresponding magnitude of fMRI cortical signal. Compared with novel objects, repeated objects elicited maximal cortical response reduction when initially presented for 250 ms. Counter-intuitively, initially seeing an object for a longer duration significantly reduced the magnitude of this effect. This ‘rise-and-fall’ pattern was also evident for the corresponding behavioral priming. To account for these findings, we propose that the earlier interval of an exposure to a visual stimulus results in a fine-tuning of the cortical response, while additional exposure promotes selection of a subset of key features for continued representation. These two independent mechanisms complement each other in shaping object representations with experience. PMID:15716471

Perceived orientation in free-fall dependson visual, postural, and architectural factors

NASA Technical Reports Server (NTRS)

Lackner, J. R.; Graybiel, A.

1983-01-01

In orbital flight and in the free-fall phase of parabolic flight, feelings of inversion of self and spacecraft, or aircraft, are often experienced. It is shown here that perceived orientation in free-fall is dependent on the position of one's body in relation to the aircraft, the architectural features of the aircraft, and one's visual appreciation of the relative configurations of his body and the aircraft. Compelling changes in the apparent orientation of one's body and of the aircraft can be reliably and systematically induced by manipulating this relationship. Moreover, while free-floating in the absence of visual, touch, and pressure stimulation, all sense of orientation to the surroundings may be lost with only an awareness of the relative configuration of the body preserved. The absences of falling sensations during weightlessness points to the importance of visual and cognitive factors in eliciting such sensations.

Spatially Pooled Contrast Responses Predict Neural and Perceptual Similarity of Naturalistic Image Categories

PubMed Central

Groen, Iris I. A.; Ghebreab, Sennay; Lamme, Victor A. F.; Scholte, H. Steven

2012-01-01

The visual world is complex and continuously changing. Yet, our brain transforms patterns of light falling on our retina into a coherent percept within a few hundred milliseconds. Possibly, low-level neural responses already carry substantial information to facilitate rapid characterization of the visual input. Here, we computationally estimated low-level contrast responses to computer-generated naturalistic images, and tested whether spatial pooling of these responses could predict image similarity at the neural and behavioral level. Using EEG, we show that statistics derived from pooled responses explain a large amount of variance between single-image evoked potentials (ERPs) in individual subjects. Dissimilarity analysis on multi-electrode ERPs demonstrated that large differences between images in pooled response statistics are predictive of more dissimilar patterns of evoked activity, whereas images with little difference in statistics give rise to highly similar evoked activity patterns. In a separate behavioral experiment, images with large differences in statistics were judged as different categories, whereas images with little differences were confused. These findings suggest that statistics derived from low-level contrast responses can be extracted in early visual processing and can be relevant for rapid judgment of visual similarity. We compared our results with two other, well- known contrast statistics: Fourier power spectra and higher-order properties of contrast distributions (skewness and kurtosis). Interestingly, whereas these statistics allow for accurate image categorization, they do not predict ERP response patterns or behavioral categorization confusions. These converging computational, neural and behavioral results suggest that statistics of pooled contrast responses contain information that corresponds with perceived visual similarity in a rapid, low-level categorization task. PMID:23093921

Factors associated with developing a fear of falling in subjects with primary open-angle glaucoma.

PubMed

Adachi, Sayaka; Yuki, Kenya; Awano-Tanabe, Sachiko; Ono, Takeshi; Shiba, Daisuke; Murata, Hiroshi; Asaoka, Ryo; Tsubota, Kazuo

2018-02-13

To investigate the relationship between clinical risk factors, including visual field (VF) defects and visual acuity, and a fear of falling, among patients with primary open-angle glaucoma (POAG). All participants answered the following question at a baseline ophthalmic examination: Are you afraid of falling? The same question was then answered every 12 months for 3 years. A binocular integrated visual field was calculated by merging a patient's monocular Humphrey field analyzer VFs, using the 'best sensitivity' method. The means of total deviation values in the whole, superior peripheral, superior central, inferior central, and inferior peripheral VFs were calculated. The relationship between these mean VF measurements, and various clinical factors, against patients' baseline fear of falling and future fear of falling was analyzed using multiple logistic regression. Among 392 POAG subjects, 342 patients (87.2%) responded to the fear of falling question at least twice in the 3 years study period. The optimal regression model for patients' baseline fear of falling included age, gender, mean of total deviation values in the inferior peripheral VF and number of previous falls. The optimal regression equation for future fear of falling included age, gender, mean of total deviation values in the inferior peripheral VF and number of previous falls. Defects in the inferior peripheral VF area are significantly related to the development of a fear of falling.

Seniors' self-preservation by maintaining established self and defying deterioration - A grounded theory.

PubMed

Eriksson, Jeanette Källstrand; Hildingh, Cathrine; Buer, Nina; Thulesius, Hans

2016-01-01

The purpose of this classic grounded theory study was to understand how seniors who are living independently resolve issues influenced by visual impairment and high fall risk. We interviewed and observed 13 seniors with visual impairment in their homes. We also interviewed six visual instructors with experience from many hundreds of relevant incidents from the same group of seniors. We found that the seniors are resolving their main concern of "remaining themselves as who they used to be" by self-preservation. Within this category, the strategies maintaining the established self and defying deterioration emerged as the most prominent in our data. The theme maintaining the established self is mostly guided by change inertia and includes living the past (retaining past activities, reminiscing, and keeping the home intact) and facading (hiding impairment, leading to avoidance of becoming a burden and to risk juggling). Defying deterioration is a proactive scheme and involves moving (by exercising, adapting activities, using walking aids, driving), adapting (by finding new ways), and networking by sustaining old support networks or finding new networks. Self-preservation is generic human behavior and modifying this theory to other fields may therefore be worthwhile. In addition, health care providers may have use for the theory in fall preventive planning.

Seniors’ self-preservation by maintaining established self and defying deterioration – A grounded theory

PubMed Central

Eriksson, Jeanette Källstrand; Hildingh, Cathrine; Buer, Nina; Thulesius, Hans

2016-01-01

The purpose of this classic grounded theory study was to understand how seniors who are living independently resolve issues influenced by visual impairment and high fall risk. We interviewed and observed 13 seniors with visual impairment in their homes. We also interviewed six visual instructors with experience from many hundreds of relevant incidents from the same group of seniors. We found that the seniors are resolving their main concern of “remaining themselves as who they used to be” by self-preservation. Within this category, the strategies maintaining the established self and defying deterioration emerged as the most prominent in our data. The theme maintaining the established self is mostly guided by change inertia and includes living the past (retaining past activities, reminiscing, and keeping the home intact) and facading (hiding impairment, leading to avoidance of becoming a burden and to risk juggling). Defying deterioration is a proactive scheme and involves moving (by exercising, adapting activities, using walking aids, driving), adapting (by finding new ways), and networking by sustaining old support networks or finding new networks. Self-preservation is generic human behavior and modifying this theory to other fields may therefore be worthwhile. In addition, health care providers may have use for the theory in fall preventive planning. PMID:27172511

Risk factors for falls in community-dwelling patients with Alzheimer's disease and dementia with Lewy bodies: walking with visuocognitive impairment may cause a fall.

PubMed

Kudo, Yuri; Imamura, Toru; Sato, Atsushi; Endo, Naoto

2009-01-01

To identify risk factors for falls in community-dwelling patients with Alzheimer's disease (AD) and dementia with Lewy bodies (DLB). 78 consecutive patients (51 AD, 27 DLB) were recruited from the Niigata Rehabilitation Hospital memory clinic. We assessed the number of falls each patient had had in the previous 4 months. The data for DLB patients without motor parkinsonism were analyzed both as part of the whole DLB group and separately to determine the effect of parkinsonism alone on falls. Of 78 patients, 17 (21.8%) reported at least 1 fall during the period. A diagnosis of DLB, visual hallucinations, parkinsonism and cognitive fluctuation were significant predictors, but none of them was significant in the stepwise multivariate analysis. After excluding patients with parkinsonism, the use of hypnotics-anxiolytics and a worse score on the constructional task were significant and independent predictors of falling. Parkinsonism was a major risk factor for falls. When AD or DLB patients walk with incongruent visual information, they may increase their postural sway or instability, because of their executive dysfunction. If elementary and/or higher-order visuocognitive impairment in AD or DLB patients alters visual information sufficiently, they may fall when walking. Copyright 2009 S. Karger AG, Basel.

Use of the Dynamic Visual Acuity Test as a screener for community-dwelling older adults who fall.

PubMed

Honaker, Julie A; Shepard, Neil T

2011-01-01

Adequate function of the peripheral vestibular system, specifically the vestibulo-ocular reflex (VOR; a network of neural connections between the peripheral vestibular system and the extraocular muscles) is essential for maintaining stable vision during head movements. Decreased visual acuity resulting from an impaired peripheral vestibular system may impede balance and postural control and place an individual at risk of falling. Therefore, sensitive measures of the vestibular system are warranted to screen for the tendency to fall, alerting clinicians to recommend further risk of falling assessment and referral to a falling risk reduction program. Dynamic Visual Acuity (DVA) testing is a computerized VOR assessment method to evaluate the peripheral vestibular system during head movements; reduced visual acuity as documented with DVA testing may be sensitive to screen for falling risk. This study examined the sensitivity and specificity of the computerized DVA test with yaw plane head movements for identifying community-dwelling adults (58-78 years) who are prone to falling. A total of 16 older adults with a history of two or more unexplained falls in the previous twelve months and 16 age and gender matched controls without a history of falls in the previous twelve months participated. Computerized DVA with horizontal head movements at a fixed velocity of 120 deg/sec was measured and compared with the Dynamic Gait Index (DGI) a gold standard gait assessment measurement for identifying falling risk. Receiver operating characteristics (ROC) curve analysis and area under the ROC curve (AUC) were used to assess the sensitivity and specificity of the computerized DVA as a screening measure for falling risk as determined by the DGI. Results suggested a link between computerized DVA and the propensity to fall; DVA in the yaw plane was found to be a sensitive (92%) and accurate screening measure when using a cutoff logMAR value of >0.25.

A measure of fall risk behaviors and perceptions among community-dwelling older adults.

PubMed

Yuen, Hon Keung; Carter, Rickey E

2006-01-01

Relatively little is known about the interaction between behavioral and environmental circumstances associated with falls among community-dwelling older adults. This study is designed to develop an instrument that measures community-dwelling older adults' participation in and perceptions of fall risk behaviors. Eighty-seven community-dwelling older adults aged 60 or above (mean +/- SD = 76 +/- 7.9), who had experienced at least one fall in the past 12 months, completed a questionnaire dealing with frequency of their participation in fall risk behaviors, their perceptions of these behaviors, and their fall history. Data were subjected to exploratory factor analysis. A 20-item instrument consisting of three constructs was presented as the Fall Risk Behaviors and Perceptions Scale (FRB&PS). Two of the three constructs of the instrument were de-stabilizers and non-supports, both of which measure participation in fall risk behaviors; the third was perceptions of fall risk behaviors. Internal consistency coefficient of the FRB&PS is 0.733 with a root mean square error of approximation (RMSEA) score of 0.075, which indicates an adequate model fit. Results from the stepwise regression analyses indicated that adults aged 75 and above (the old-old) participated less frequently in fall risk activities (p = 0.025), and had more knowledge about fall risks as measured by a higher perception score (p = 0.025) than those aged 60 to 75 (the young-old). Older men tended to participate more frequently in fall risk activities (p = 0.020) than older women; in addition, those older adults who are more mobile (p = 0.002) also participated more frequently in fall risk behaviors than those who are less mobile. Preliminary findings indicate that the pilot FRB&PS is a reliable and valid instrument to measure community-dwelling older adults' participation in and perceptions of fall risk behaviors. Additional psychometric validation of the FRB&PS on predicting the likelihood of falls is warranted.

Perception and Processing of Faces in the Human Brain Is Tuned to Typical Feature Locations

PubMed Central

Schwarzkopf, D. Samuel; Alvarez, Ivan; Lawson, Rebecca P.; Henriksson, Linda; Kriegeskorte, Nikolaus; Rees, Geraint

2016-01-01

Faces are salient social stimuli whose features attract a stereotypical pattern of fixations. The implications of this gaze behavior for perception and brain activity are largely unknown. Here, we characterize and quantify a retinotopic bias implied by typical gaze behavior toward faces, which leads to eyes and mouth appearing most often in the upper and lower visual field, respectively. We found that the adult human visual system is tuned to these contingencies. In two recognition experiments, recognition performance for isolated face parts was better when they were presented at typical, rather than reversed, visual field locations. The recognition cost of reversed locations was equal to ∼60% of that for whole face inversion in the same sample. Similarly, an fMRI experiment showed that patterns of activity evoked by eye and mouth stimuli in the right inferior occipital gyrus could be separated with significantly higher accuracy when these features were presented at typical, rather than reversed, visual field locations. Our findings demonstrate that human face perception is determined not only by the local position of features within a face context, but by whether features appear at the typical retinotopic location given normal gaze behavior. Such location sensitivity may reflect fine-tuning of category-specific visual processing to retinal input statistics. Our findings further suggest that retinotopic heterogeneity might play a role for face inversion effects and for the understanding of conditions affecting gaze behavior toward faces, such as autism spectrum disorders and congenital prosopagnosia. SIGNIFICANCE STATEMENT Faces attract our attention and trigger stereotypical patterns of visual fixations, concentrating on inner features, like eyes and mouth. Here we show that the visual system represents face features better when they are shown at retinal positions where they typically fall during natural vision. When facial features were shown at typical (rather than reversed) visual field locations, they were discriminated better by humans and could be decoded with higher accuracy from brain activity patterns in the right occipital face area. This suggests that brain representations of face features do not cover the visual field uniformly. It may help us understand the well-known face-inversion effect and conditions affecting gaze behavior toward faces, such as prosopagnosia and autism spectrum disorders. PMID:27605606

Sustained Splits of Attention within versus across Visual Hemifields Produce Distinct Spatial Gain Profiles.

PubMed

Walter, Sabrina; Keitel, Christian; Müller, Matthias M

2016-01-01

Visual attention can be focused concurrently on two stimuli at noncontiguous locations while intermediate stimuli remain ignored. Nevertheless, behavioral performance in multifocal attention tasks falters when attended stimuli fall within one visual hemifield as opposed to when they are distributed across left and right hemifields. This "different-hemifield advantage" has been ascribed to largely independent processing capacities of each cerebral hemisphere in early visual cortices. Here, we investigated how this advantage influences the sustained division of spatial attention. We presented six isoeccentric light-emitting diodes (LEDs) in the lower visual field, each flickering at a different frequency. Participants attended to two LEDs that were spatially separated by an intermediate LED and responded to synchronous events at to-be-attended LEDs. Task-relevant pairs of LEDs were either located in the same hemifield ("within-hemifield" conditions) or separated by the vertical meridian ("across-hemifield" conditions). Flicker-driven brain oscillations, steady-state visual evoked potentials (SSVEPs), indexed the allocation of attention to individual LEDs. Both behavioral performance and SSVEPs indicated enhanced processing of attended LED pairs during "across-hemifield" relative to "within-hemifield" conditions. Moreover, SSVEPs demonstrated effective filtering of intermediate stimuli in "across-hemifield" condition only. Thus, despite identical physical distances between LEDs of attended pairs, the spatial profiles of gain effects differed profoundly between "across-hemifield" and "within-hemifield" conditions. These findings corroborate that early cortical visual processing stages rely on hemisphere-specific processing capacities and highlight their limiting role in the concurrent allocation of visual attention to multiple locations.

Image-based fall detection and classification of a user with a walking support system

NASA Astrophysics Data System (ADS)

Taghvaei, Sajjad; Kosuge, Kazuhiro

2017-10-01

The classification of visual human action is important in the development of systems that interact with humans. This study investigates an image-based classification of the human state while using a walking support system to improve the safety and dependability of these systems.We categorize the possible human behavior while utilizing a walker robot into eight states (i.e., sitting, standing, walking, and five falling types), and propose two different methods, namely, normal distribution and hidden Markov models (HMMs), to detect and recognize these states. The visual feature for the state classification is the centroid position of the upper body, which is extracted from the user's depth images. The first method shows that the centroid position follows a normal distribution while walking, which can be adopted to detect any non-walking state. The second method implements HMMs to detect and recognize these states. We then measure and compare the performance of both methods. The classification results are employed to control the motion of a passive-type walker (called "RT Walker") by activating its brakes in non-walking states. Thus, the system can be used for sit/stand support and fall prevention. The experiments are performed with four subjects, including an experienced physiotherapist. Results show that the algorithm can be adapted to the new user's motion pattern within 40 s, with a fall detection rate of 96.25% and state classification rate of 81.0%. The proposed method can be implemented to other abnormality detection/classification applications that employ depth image-sensing devices.

Gravity in the Brain as a Reference for Space and Time Perception.

PubMed

Lacquaniti, Francesco; Bosco, Gianfranco; Gravano, Silvio; Indovina, Iole; La Scaleia, Barbara; Maffei, Vincenzo; Zago, Myrka

2015-01-01

Moving and interacting with the environment require a reference for orientation and a scale for calibration in space and time. There is a wide variety of environmental clues and calibrated frames at different locales, but the reference of gravity is ubiquitous on Earth. The pull of gravity on static objects provides a plummet which, together with the horizontal plane, defines a three-dimensional Cartesian frame for visual images. On the other hand, the gravitational acceleration of falling objects can provide a time-stamp on events, because the motion duration of an object accelerated by gravity over a given path is fixed. Indeed, since ancient times, man has been using plumb bobs for spatial surveying, and water clocks or pendulum clocks for time keeping. Here we review behavioral evidence in favor of the hypothesis that the brain is endowed with mechanisms that exploit the presence of gravity to estimate the spatial orientation and the passage of time. Several visual and non-visual (vestibular, haptic, visceral) cues are merged to estimate the orientation of the visual vertical. However, the relative weight of each cue is not fixed, but depends on the specific task. Next, we show that an internal model of the effects of gravity is combined with multisensory signals to time the interception of falling objects, to time the passage through spatial landmarks during virtual navigation, to assess the duration of a gravitational motion, and to judge the naturalness of periodic motion under gravity.

Disease state fingerprint for fall risk assessment.

PubMed

Similä, Heidi; Immonen, Milla

2014-01-01

Fall prevention is an important and complex multifactorial challenge, since one third of people over 65 years old fall at least once every year. A novel application of Disease State Fingerprint (DSF) algorithm is presented for holistic visualization of fall risk factors and identifying persons with falls history or decreased level of physical functioning based on fall risk assessment data. The algorithm is tested with data from 42 older adults, that went through a comprehensive fall risk assessment. Within the study population the Activities-specific Balance Confidence (ABC) scale score, Berg Balance Scale (BBS) score and the number of drugs in use were the three most relevant variables, that differed between the fallers and non-fallers. This study showed that the DSF visualization is beneficial in inspection of an individual's significant fall risk factors, since people have problems in different areas and one single assessment scale is not enough to expose all the people at risk.

Relationship Between Perceived Risk of Falling and Adoption of Precautions to Reduce Fall Risk.

PubMed

Blalock, Susan J; Gildner, Paula L; Jones, Jennifer L; Bowling, James M; Casteel, Carri H

2016-06-01

To better understand the relationship between perceived risk of falling and awareness and adoption of four specific precautions that older adults have taken to reduce this risk. Cross-sectional. Data were collected in in-person interviews conducted in the homes of study participants. Interviews conducted between March 2011 and September 2013 and lasted an average of 60-90 minutes. A stratified sampling strategy designed to enroll an equal number of homebound and nonhomebound participants was used. All participants (N = 164) were recruited from central North Carolina. Participants were asked about 1-year fall history, perceived risk of falling, restriction of activities because of fear of falling, awareness of four recommended fall prevention behaviors (exercise, annual medication review, bathroom grab bars, safe footwear), and current practice of these behaviors. In bivariate analyses, individuals who were aware of two behaviors recommended to reduce the risk of falling (exercise, use of safe footwear) and had adopted these behaviors perceived their risk of falling as lower than individuals who were aware of the recommended behaviors but had not adopted them. Moreover, in multivariate analyses, individuals who did not know that exercise is recommended to reduce the risk of falling perceived their risk of falling as lower than those who were aware of this recommendation and had adopted it. Individuals were least likely to be aware that medication reviews and exercise are recommended to reduce fall risk. Awareness of behaviors recommended to reduce fall risk appears necessary for adoption of these behaviors to reduce perceived risk. Fall-prevention campaigns should emphasize behaviors where awareness is low. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.

Impact of fall-related behaviors as risk factors for falls among the elderly patients with dementia in a geriatric facility in Japan.

PubMed

Suzuki, Mizue; Kurata, Sadami; Yamamoto, Emiko; Makino, Kumiko; Kanamori, Masao

2012-09-01

The purpose of this study was to clarify potential fall-related behaviors as fall risk factors that may predict the potential for falls among the elderly patients with dementia at a geriatric facility in Japan. This study was conducted from April 2008 to May 2009. A baseline study was conducted in April 2008 to evaluate Mini-Mental State Examination, Physical Self-Maintenance Scale, fall-related behaviors, and other factors. For statistical analysis, paired t test and logistic analysis were used to compare each item between fallers and nonfallers. A total of 135 participants were followed up for 1 year; 50 participants (37.04%) fell during that period. Results of multiple logistic regression analysis showed that the total score for fall-related behaviors was significantly related to falls. It was suggested that 11 fall-related behaviors may be effective indicators to predict falls among the elderly patients with dementia.

Visual acuity, self-reported vision and falls in the EPIC-Norfolk Eye study.

PubMed

Yip, Jennifer L Y; Khawaja, Anthony P; Broadway, David; Luben, Robert; Hayat, Shabina; Dalzell, Nichola; Bhaniani, Amit; Wareham, Nicholas; Khaw, Kay-Tee; Foster, Paul J

2014-03-01

To examine the relationship between visual acuity (VA) and self-reported vision (SRV) in relation to falls in 8317 participants of the European Prospective Investigation into Cancer-Norfolk Eye study. All participants completed a health questionnaire that included a question regarding SRV and questions regarding the number of falls in the past year. Distance VA was measured using a logMAR chart for each eye. Poor SRV was defined as those reporting fair or poor distance vision. The relationship between VA and SRV and self-rated falls was analysed by logistic regression, adjusting for age, sex, physical activity, body mass index, chronic disease, medication use and grip strength. Of 8317 participants, 26.7% (95% CI 25.7% to 27.7%) had fallen in the past 12 months. Worse VA and poorer SRV were associated with one or more falls in multivariable analysis (OR for falls=1.31, 95% CI 1.04 to 1.66 and OR=1.32, 95% CI 1.09 to 1.61, respectively). Poorer SRV was significantly associated with falls even after adjusting for VA (OR=1.28, 95% CI 1.05 to 1.57). SRV was associated with falls independently of VA and could be used as a simple proxy measure for other aspects of visual function to detect people requiring vision-related falls interventions.

Rise and fall of the two visual systems theory.

PubMed

Rossetti, Yves; Pisella, Laure; McIntosh, Robert D

2017-06-01

Among the many dissociations describing the visual system, the dual theory of two visual systems, respectively dedicated to perception and action, has yielded a lot of support. There are psychophysical, anatomical and neuropsychological arguments in favor of this theory. Several behavioral studies that used sensory and motor psychophysical parameters observed differences between perceptive and motor responses. The anatomical network of the visual system in the non-human primate was very readily organized according to two major pathways, dorsal and ventral. Neuropsychological studies, exploring optic ataxia and visual agnosia as characteristic deficits of these two pathways, led to the proposal of a functional double dissociation between visuomotor and visual perceptual functions. After a major wave of popularity that promoted great advances, particularly in knowledge of visuomotor functions, the guiding theory is now being reconsidered. Firstly, the idea of a double dissociation between optic ataxia and visual form agnosia, as cleanly separating visuomotor from visual perceptual functions, is no longer tenable; optic ataxia does not support a dissociation between perception and action and might be more accurately viewed as a negative image of action blindsight. Secondly, dissociations between perceptive and motor responses highlighted in the framework of this theory concern a very elementary level of action, even automatically guided action routines. Thirdly, the very rich interconnected network of the visual brain yields few arguments in favor of a strict perception/action dissociation. Overall, the dissociation between motor function and perceptive function explored by these behavioral and neuropsychological studies can help define an automatic level of action organization deficient in optic ataxia and preserved in action blindsight, and underlines the renewed need to consider the perception-action circle as a functional ensemble. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Fear of Falling and Older Adult Peer Production of Audio-Visual Discussion Material

ERIC Educational Resources Information Center

Bailey, Cathy; King, Karen; Dromey, Ben; Wynne, Ciaran

2010-01-01

A growing body of work suggests that negative stereotypes of, and associations between, falling, fear of falling, and ageing, may mean that older adults reject falls information and advice. Against a widely accepted backdrop of demographic ageing in Europe and that alleviating the impacts of falls and fear of falling are pressing health care…

Laserlight cues for gait freezing in Parkinson's disease: an open-label study.

PubMed

Donovan, S; Lim, C; Diaz, N; Browner, N; Rose, P; Sudarsky, L R; Tarsy, D; Fahn, S; Simon, D K

2011-05-01

Freezing of gait (FOG) and falls are major sources of disability for Parkinson's disease (PD) patients, and show limited responsiveness to medications. We assessed the efficacy of visual cues for overcoming FOG in an open-label study of 26 patients with PD. The change in the frequency of falls was a secondary outcome measure. Subjects underwent a 1-2 month baseline period of use of a cane or walker without visual cues, followed by 1 month using the same device with the laserlight visual cue. The laserlight visual cue was associated with a modest but significant mean reduction in FOG Questionnaire (FOGQ) scores of 1.25 ± 0.48 (p = 0.0152, two-tailed paired t-test), representing a 6.6% improvement compared to the mean baseline FOGQ scores of 18.8. The mean reduction in fall frequency was 39.5 ± 9.3% with the laserlight visual cue among subjects experiencing at least one fall during the baseline and subsequent study periods (p = 0.002; two-tailed one-sample t-test with hypothesized mean of 0). Though some individual subjects may have benefited, the overall mean performance on the timed gait test (TGT) across all subjects did not significantly change. However, among the 4 subjects who underwent repeated testing of the TGT, one showed a 50% mean improvement in TGT performance with the laserlight visual cue (p = 0.005; two-tailed paired t-test). This open-label study provides evidence for modest efficacy of a laserlight visual cue in overcoming FOG and reducing falls in PD patients. Copyright © 2010 Elsevier Ltd. All rights reserved.

Randomized controlled trial comparing tailoring methods of multimedia-based fall prevention education for community-dwelling older adults.

PubMed

Schepens, Stacey L; Panzer, Victoria; Goldberg, Allon

2011-01-01

We attempted to determine whether multimedia fall prevention education using different instructional strategies increases older adults' knowledge of fall threats and their fall prevention behaviors. Fifty-three community-dwelling older adults were randomized to iwo educational groups or a control group. Multimedia-based educational interventions to increase fall threats knowledge and encourage fall prevention behaviors had two tailoring strategies: (1) improve content realism for individual learners (authenticity group) and (2) highlight program goals and benefits while using participants' content selections (motivation group). Knowledge was measured at baseline and 1-mo follow-up. Participants recorded prevention behaviors for 1 mo. Intervention group participants showed greater knowledge gains and posttest knowledge than did control group participants. The motivation group engaged in more prevention behaviors over 1 mo than did the other groups. Tailoring fall prevention education by addressing authenticity and motivation successfully improved fall threats knowledge. Combining motivational strategies with multimedia education increased the effectiveness of the intervention in encouraging fall prevention behaviors.

A Portable Platform for Evaluation of Visual Performance in Glaucoma Patients

PubMed Central

Rosen, Peter N.; Boer, Erwin R.; Gracitelli, Carolina P. B.; Abe, Ricardo Y.; Diniz-Filho, Alberto; Marvasti, Amir H.; Medeiros, Felipe A.

2015-01-01

Purpose To propose a new tablet-enabled test for evaluation of visual performance in glaucoma, the PERformance CEntered Portable Test (PERCEPT), and to evaluate its ability to predict history of falls and motor vehicle crashes. Design Cross-sectional study. Methods The study involved 71 patients with glaucomatous visual field defects on standard automated perimetry (SAP) and 59 control subjects. The PERCEPT was based on the concept of increasing visual task difficulty to improve detection of central visual field losses in glaucoma patients. Subjects had to perform a foveal 8-alternative-forced-choice orientation discrimination task, while detecting a simultaneously presented peripheral stimulus within a limited presentation time. Subjects also underwent testing with the Useful Field of View (UFOV) divided attention test. The ability to predict history of motor vehicle crashes and falls was investigated by odds ratios and incident-rate ratios, respectively. Results When adjusted for age, only the PERCEPT processing speed parameter showed significantly larger values in glaucoma compared to controls (difference: 243ms; P<0.001). PERCEPT results had a stronger association with history of motor vehicle crashes and falls than UFOV. Each 1 standard deviation increase in PERCEPT processing speed was associated with an odds ratio of 2.69 (P = 0.003) for predicting history of motor vehicle crashes and with an incident-rate ratio of 1.95 (P = 0.003) for predicting history of falls. Conclusion A portable platform for testing visual function was able to detect functional deficits in glaucoma, and its results were significantly associated with history of involvement in motor vehicle crashes and history of falls. PMID:26445501

The occurrence of visual and cognitive impairment, and eye diseases in the super-elderly in Japan: a cross-sectional single-center study.

PubMed

Fukuoka, Hideki; Nagaya, Masahiro; Toba, Kenji

2015-10-29

The current state of eye diseases and treatments in the elderly as well as the relationships between dementia and systemic diseases remain unclear. Therefore, this study evaluated the prevalence of eye diseases, visual impairment, cognitive impairment, and falls (which are an important health issue and are considered one of the Geriatric Giants) in super-elderly people in Japan. The subjects were 31 elderly people (62 eyes; mean age: 84.6 ± 8.8 years; age range 61-98 years) who were admitted to a geriatric health services facility. Eye treatment status, systemic diseases, dementia, and recent falls were investigated. Eye examinations including vision and intraocular pressure measurement, and slit-lamp biomicroscopy were conducted. Mean best corrected visual acuity (logMAR) was 0.51 ± 0.56, and mean intraocular pressure was 13.7 ± 3.5 mmHg. Approximately half of the subjects exhibited excavation of the optic nerve head including cataracts and glaucoma. Ten subjects had visual impairment (i.e., visual acuity of the eye with the better vision <20/40). The mean Hasegawa dementia scale scores between the visually impaired and non-visually impaired groups were 10.2 ± 6 and 16 ± 8 points, respectively (p < 0.05). Furthermore, 70% of subjects with visual impairment experienced a fall in the past year compared to 48% of those without visual impairment, although the difference was not significant. Regarding systemic diseases, there were 6, 5, and 15 cases of diabetes, hyperlipidemia, and hypertension, respectively. There was no significant difference between these systemic diseases and visual function after adjusted for age and gender. The percentages of patients with age-related eye diseases and poor visual acuity in a geriatric health services facility were extremely high. Compared to those without visual impairment, those with visual impairment had lower dementia scores and a higher rate of falls.

Regional white matter lesions predict falls in patients with amnestic mild cognitive impairment and Alzheimer's disease.

PubMed

Ogama, Noriko; Sakurai, Takashi; Shimizu, Atsuya; Toba, Kenji

2014-01-01

Preventive strategy for falls in demented elderly is a clinical challenge. From early-stage of Alzheimer's disease (AD), patients show impaired balance and gait. The purpose of this study is to determine whether regional white matter lesions (WMLs) can predict balance/gait disturbance and falls in elderly with amnestic mild cognitive impairment (aMCI) or AD. Cross-sectional. Hospital out-patient clinic. One hundred sixty-three patients diagnosed with aMCI or AD were classified into groups having experienced falls (n = 63) or not (n = 100) in the previous year. Cognition, depression, behavior and psychological symptoms of dementia, medication, and balance/gait function were evaluated. Regional WMLs were visually analyzed as periventricular hyperintensity in frontal caps, bands, and occipital caps, and as deep white matter hyperintensity in frontal, parietal, temporal, and occipital lobes, basal ganglia, thalamus, and brain stem. Brain atrophy was linearly measured. The fallers had a greater volume of WMLs and their posture/gait performance tended to be worse than nonfallers. Several WMLs in particular brain regions were closely associated with balance and gait impairment. Besides polypharmacy, periventricular hyperintensity in frontal caps and occipital WMLs were strong predictors for falls, even after potential risk factors for falls were considered. Regional white matter burden, independent of cognitive decline, correlates with balance/gait disturbance and predicts falls in elderly with aMCI and AD. Careful insight into regional WMLs on brain magnetic resonance may greatly help to diagnose demented elderly with a higher risk of falls. Copyright © 2014 American Medical Directors Association, Inc. Published by Elsevier Inc. All rights reserved.

Randomized Controlled Trial Comparing Tailoring Methods of Multimedia-Based Fall Prevention Education for Community-Dwelling Older Adults

PubMed Central

Schepens, Stacey L.; Panzer, Victoria; Goldberg, Allon

2012-01-01

OBJECTIVE We attempted to determine whether multimedia fall prevention education using different instructional strategies increases older adults’ knowledge of fall threats and their fall prevention behaviors. METHOD Fifty-three community-dwelling older adults were randomized to two educational groups or a control group. Multimedia-based educational interventions to increase fall threats knowledge and encourage fall prevention behaviors had two tailoring strategies: (1) improve content realism for individual learners (authenticity group) and (2) highlight program goals and benefits while using participants’ content selections (motivation group). Knowledge was measured at baseline and 1-mo follow-up. Participants recorded prevention behaviors for 1 mo. RESULTS Intervention group participants showed greater knowledge gains and posttest knowledge than did control group participants. The motivation group engaged in more prevention behaviors over 1 mo than did the other groups. CONCLUSION Tailoring fall prevention education by addressing authenticity and motivation successfully improved fall threats knowledge. Combining motivational strategies with multimedia education increased the effectiveness of the intervention in encouraging fall prevention behaviors. PMID:22214115

Visual Sensor Based Abnormal Event Detection with Moving Shadow Removal in Home Healthcare Applications

PubMed Central

Lee, Young-Sook; Chung, Wan-Young

2012-01-01

Vision-based abnormal event detection for home healthcare systems can be greatly improved using visual sensor-based techniques able to detect, track and recognize objects in the scene. However, in moving object detection and tracking processes, moving cast shadows can be misclassified as part of objects or moving objects. Shadow removal is an essential step for developing video surveillance systems. The goal of the primary is to design novel computer vision techniques that can extract objects more accurately and discriminate between abnormal and normal activities. To improve the accuracy of object detection and tracking, our proposed shadow removal algorithm is employed. Abnormal event detection based on visual sensor by using shape features variation and 3-D trajectory is presented to overcome the low fall detection rate. The experimental results showed that the success rate of detecting abnormal events was 97% with a false positive rate of 2%. Our proposed algorithm can allow distinguishing diverse fall activities such as forward falls, backward falls, and falling asides from normal activities. PMID:22368486

Gender Differences and the Risk of Falls in Individuals with Profound Vision Loss

ERIC Educational Resources Information Center

Ray, Christopher T.; Wolf, Steven L.

2010-01-01

Adults with visual impairments experience a loss of balance and mobility, which presents a barrier to independence and is associated with the fear of falling. The purpose of this study was to determine the extent to which visual status, age, gender, body mass index (BMI), and the strength of quadriceps and hamstrings contribute to compromised…

The association between primary open-angle glaucoma and fall: an observational study.

PubMed

Tanabe, Sachiko; Yuki, Kenya; Ozeki, Naoki; Shiba, Daisuke; Tsubota, Kazuo

2012-01-01

Falls are among the most serious public health concerns for the elderly. Information conveyed via the visual sense is relevant to postural balance and movement, and proper visual function is essential to avoid falls. Here we investigated the prevalence of injurious falls among patients with primary open-angle glaucoma (POAG) who were more than 45 years old, compared with comparably aged healthy subjects. This is a cross-sectional study. Consecutive patients who visited the Tanabe Eye Clinic, Yamanashi, Japan between January 1 and March 30, 2009 were screened for eligibility by ophthalmic examination. A total of 117 control subjects (77 men, 40 women; aged 60.2 ± 7.5 years) who were free of ocular disease and 101 POAG patients (58 men, 43 women; aged 62.3 ± 8.7 years) were consecutively enrolled. Participants answered a questionnaire on injurious fall experience during the previous 10 years. The prevalence of injurious fall in subjects with POAG versus healthy controls was examined with Fisher's exact test. Adjusted odds ratios and 95% confidence intervals were estimated with logistic regression models for the subjects with POAG (factors: age, gender, mean deviation in the better eye or worse eye). The self-reported prevalence of injurious fall was 0.9% (1/117) in the control group and 6.9% (7/101) in the POAG group. The association between injurious fall and POAG was statistically significant (P = 0.026, Fisher's exact test). Within the POAG patients, the group reporting falls was significantly older and had a lower BMI, worse BCVA, and worse mean deviation in both the better and worse eye than the group reporting no falls. Worse mean deviation in the eye with the better visual field (odds ratios 0.75; 95% confidence intervals: 0.57 to 0.99; P = 0.036) was a significant risk factor for injurious falls in subjects with POAG. POAG was significantly associated with injurious falls.

Visuo-motor coordination and internal models for object interception.

PubMed

Zago, Myrka; McIntyre, Joseph; Senot, Patrice; Lacquaniti, Francesco

2009-02-01

Intercepting and avoiding collisions with moving objects are fundamental skills in daily life. Anticipatory behavior is required because of significant delays in transforming sensory information about target and body motion into a timed motor response. The ability to predict the kinematics and kinetics of interception or avoidance hundreds of milliseconds before the event may depend on several different sources of information and on different strategies of sensory-motor coordination. What are exactly the sources of spatio-temporal information and what are the control strategies remain controversial issues. Indeed, these topics have been the battlefield of contrasting views on how the brain interprets visual information to guide movement. Here we attempt a synthetic overview of the vast literature on interception. We discuss in detail the behavioral and neurophysiological aspects of interception of targets falling under gravity, as this topic has received special attention in recent years. We show that visual cues alone are insufficient to predict the time and place of interception or avoidance, and they need to be supplemented by prior knowledge (or internal models) about several features of the dynamic interaction with the moving object.

Split Fovea Theory and the Role of the Two Cerebral Hemispheres in Reading: A Review of the Evidence

ERIC Educational Resources Information Center

Ellis, Andrew W.; Brysbaert, Marc

2010-01-01

Split fovea theory proposes that when the eyes are fixated within a written word, visual information about the letters falling to the left of fixation is projected initially to the right cerebral hemisphere while visual information about the letters falling to the right of fixation is projected to the left cerebral hemisphere. The two parts of the…

Effectiveness of a home-based cognitive behavioral program to manage concerns about falls in community-dwelling, frail older people: results of a randomized controlled trial.

PubMed

Dorresteijn, Tanja A C; Zijlstra, G A Rixt; Ambergen, Antonius W; Delbaere, Kim; Vlaeyen, Johan W S; Kempen, Gertrudis I J M

2016-01-06

Concerns about falls are common among older people. These concerns, also referred to as fear of falling, can have serious physical and psychosocial consequences, such as functional decline, increased risk of falls, activity restriction, and lower social participation. Although cognitive behavioral group programs to reduce concerns about falls are available, no home-based approaches for older people with health problems, who may not be able to attend such group programs are available yet. The aim of this study was to assess the effectiveness of a home-based cognitive behavioral program on concerns about falls, in frail, older people living in the community. In a randomized controlled trial in the Netherlands, 389 people aged 70 years and older, in fair or poor perceived health, who reported at least some concerns about falls and related activity avoidance were allocated to a control (n = 195) or intervention group (n = 194). The intervention was a home-based, cognitive behavioral program consisting of seven sessions including three home visits and four telephone contacts. The program aims to instill adaptive and realistic views about fall risks via cognitive restructuring and to increase activity and safe behavior using goal setting and action planning and was facilitated by community nurses. Control group participants received usual care. Outcomes at 5 and 12 months follow-up were concerns about falls, activity avoidance due to concerns about falls, disability and falls. At 12 months, the intervention group showed significant lower levels of concerns about falls compared to the control group. Furthermore, significant reductions in activity avoidance, disability and indoor falls were identified in the intervention group compared with the control group. Effect sizes were small to medium. No significant difference in total number of falls was noted between the groups. The home-based, cognitive behavioral program significantly reduces concerns about falls, related activity avoidance, disability and indoor falls in community-living, frail older people. The program may prolong independent living and provides an alternative for those people who are not able or willing to attend group programs. ClinicalTrials.gov, NCT01358032. Registered 17 May 2011.

Falls and health status in elderly women following first eye cataract surgery: a randomised controlled trial

PubMed Central

Harwood, R H; Foss, A J E; Osborn, F; Gregson, R M; Zaman, A; Masud, T

2005-01-01

Background/aim: A third of elderly people fall each year. Poor vision is associated with increased risk of falls. The authors aimed to determine if first eye cataract surgery reduces the risk of falling, and to measure associated health gain. Methods: 306 women aged over 70, with cataract, were randomised to expedited (approximately 4 weeks) or routine (12 months wait) surgery. Falls were ascertained by diary, with follow up every 3 months. Health status was measured after 6 months. Results: Visual function improved in the operated group (corrected binocular acuity improved by 0.25 logMAR units; 8% had acuity worse than 6/12 compared with 37% of controls). Over 12 months of follow up, 76 (49%) operated participants fell at least once, and 28 (18%) fell more than once. 69 (45%) unoperated participants fell at least once, 38 (25%) fell more than once. Rate of falling was reduced by 34% in the operated group (rate ratio 0.66, 95% confidence interval 0.45 to 0.96, p = 0.03). Activity, anxiety, depression, confidence, visual disability, and handicap all improved in the operated group compared with the control group. Four participants in the operated group had fractures (3%), compared with 12 (8%) in the control group (p = 0.04). Conclusion: First eye cataract surgery reduces the rate of falling, and risk of fractures and improves visual function and general health status. PMID:15615747

Visual accumulation tube for size analysis of sands

USGS Publications Warehouse

Colby, B.C.; Christensen, R.P.

1956-01-01

The visual-accumulation-tube method was developed primarily for making size analyses of the sand fractions of suspended-sediment and bed-material samples. Because the fundamental property governing the motion of a sediment particle in a fluid is believed to be its fall velocity. the analysis is designed to determine the fall-velocity-frequency distribution of the individual particles of the sample. The analysis is based on a stratified sedimentation system in which the sample is introduced at the top of a transparent settling tube containing distilled water. The procedure involves the direct visual tracing of the height of sediment accumulation in a contracted section at the bottom of the tube. A pen records the height on a moving chart. The method is simple and fast, provides a continuous and permanent record, gives highly reproducible results, and accurately determines the fall-velocity characteristics of the sample. The apparatus, procedure, results, and accuracy of the visual-accumulation-tube method for determining the sedimentation-size distribution of sands are presented in this paper.

Evaluation of Postural Control in Patients with Glaucoma Using a Virtual Reality Environment.

PubMed

Diniz-Filho, Alberto; Boer, Erwin R; Gracitelli, Carolina P B; Abe, Ricardo Y; van Driel, Nienke; Yang, Zhiyong; Medeiros, Felipe A

2015-06-01

To evaluate postural control using a dynamic virtual reality environment and the relationship between postural metrics and history of falls in patients with glaucoma. Cross-sectional study. The study involved 42 patients with glaucoma with repeatable visual field defects on standard automated perimetry (SAP) and 38 control healthy subjects. Patients underwent evaluation of postural stability by a force platform during presentation of static and dynamic visual stimuli on stereoscopic head-mounted goggles. The dynamic visual stimuli presented rotational and translational ecologically valid peripheral background perturbations. Postural stability was also tested in a completely dark field to assess somatosensory and vestibular contributions to postural control. History of falls was evaluated by a standard questionnaire. Torque moments around the center of foot pressure on the force platform were measured, and the standard deviations of the torque moments (STD) were calculated as a measurement of postural stability and reported in Newton meters (Nm). The association with history of falls was investigated using Poisson regression models. Age, gender, body mass index, severity of visual field defect, best-corrected visual acuity, and STD on dark field condition were included as confounding factors. Patients with glaucoma had larger overall STD than controls during both translational (5.12 ± 2.39 Nm vs. 3.85 ± 1.82 Nm, respectively; P = 0.005) and rotational stimuli (5.60 ± 3.82 Nm vs. 3.93 ± 2.07 Nm, respectively; P = 0.022). Postural metrics obtained during dynamic visual stimuli performed better in explaining history of falls compared with those obtained in static and dark field condition. In the multivariable model, STD values in the mediolateral direction during translational stimulus were significantly associated with a history of falls in patients with glaucoma (incidence rate ratio, 1.85; 95% confidence interval, 1.30-2.63; P = 0.001). The study presented and validated a novel paradigm for evaluation of balance control in patients with glaucoma on the basis of the assessment of postural reactivity to dynamic visual stimuli using a virtual reality environment. The newly developed metrics were associated with a history of falls and may help to provide a better understanding of balance control in patients with glaucoma. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Evaluation of Postural Control in Glaucoma Patients Using a Virtual 1 Reality Environment

PubMed Central

Diniz-Filho, Alberto; Boer, Erwin R.; Gracitelli, Carolina P. B.; Abe, Ricardo Y.; van Driel, Nienke; Yang, Zhiyong; Medeiros, Felipe A.

2015-01-01

Purpose To evaluate postural control using a dynamic virtual reality environment and the relationship between postural metrics and history of falls in glaucoma patients. Design Cross-sectional study. Participants The study involved 42 glaucoma patients with repeatable visual field defects on standard automated perimetry (SAP) and 38 control healthy subjects. Methods Patients underwent evaluation of postural stability by a force platform during presentation of static and dynamic visual stimuli on stereoscopic head-mounted goggles. The dynamic visual stimuli presented rotational and translational ecologically valid peripheral background perturbations. Postural stability was also tested in a completely dark field to assess somatosensory and vestibular contributions to postural control. History of falls was evaluated by a standard questionnaire. Main Outcome Measures Torque moments around the center of foot pressure on the force platform were measured and the standard deviations (STD) of these torque moments were calculated as a measurement of postural stability and reported in Newton meter (Nm). The association with history of falls was investigated using Poisson regression models. Age, gender, body mass index, severity of visual field defect, best-corrected visual acuity, and STD on dark field condition were included as confounding factors. Results Glaucoma patients had larger overall STD than controls during both translational (5.12 ± 2.39 Nm vs. 3.85 ± 1.82 Nm, respectively; P = 0.005) as well as rotational stimuli (5.60 ± 3.82 Nm vs. 3.93 ± 2.07 Nm, respectively; P = 0.022). Postural metrics obtained during dynamic visual stimuli performed better in explaining history of falls compared to those obtained in static and dark field condition. In the multivariable model, STD values in the mediolateral direction during translational stimulus were significantly associated with history of falls in glaucoma patients (incidence-rate ratio = 1.85; 95% CI: 1.30 – 2.63; P = 0.001). Conclusions The study presented and validated a novel paradigm for evaluation of balance control in glaucoma patients based on the assessment of postural reactivity to dynamic visual stimuli using a virtual reality environment. The newly developed metrics were associated with history of falls and may help to provide a better understanding of balance control in glaucoma patients. PMID:25892017

Gait and functionality of individuals with visual impairment who participate in sports.

PubMed

da Silva, Edson Soares; Fischer, Gabriela; da Rosa, Rodrigo Gomes; Schons, Pedro; Teixeira, Luísa Beatriz Trevisan; Hoogkamer, Wouter; Peyré-Tartaruga, Leonardo Alexandre

2018-05-01

Individuals with visual impairment (VI) have often been observed to walk slower than individuals with unimpaired vision. These observations might be confounded by typical low levels of physical activity and greater sedentary behavior in individuals with VI than the overall population. Here, we compared gait and balance measures between individuals with VI who participate in disability sports, and activity level matched sighted individuals. We assessed static balance, anthropometry, self-selected walking speed, locomotion rehabilitation index, and lower limb muscular endurance; and applied physical activity level and fear of falling questionnaires. Individuals with VI who participate in disability sports, self-selected a similar walking speed (1.29 ± 0.26 m/s) as active sighted individuals (1.39 ± 0.21 m/s). Locomotor rehabilitation index and muscular endurance of lower limbs were also similar between groups. Individuals with VI presented lower static balance (42.0 ± 17.0s) than the sighted control group (45.0 ± 0s) when the controls were tested with their eyes open. However, no difference was found when the controls were tested with their eyes closed (30.3 ± 17.0s). Furthermore, individuals with VI showed a greater fear of falling. In conclusion, individuals with VI who participate in disability sports, as goalball and football, walk with similar self-selected walking speeds as active sighted individuals, but have slightly worse static balance and fear of falling. Copyright © 2018 Elsevier B.V. All rights reserved.

Macular degeneration affects eye movement behavior during visual search.

PubMed

Van der Stigchel, Stefan; Bethlehem, Richard A I; Klein, Barrie P; Berendschot, Tos T J M; Nijboer, Tanja C W; Dumoulin, Serge O

2013-01-01

Patients with a scotoma in their central vision (e.g., due to macular degeneration, MD) commonly adopt a strategy to direct the eyes such that the image falls onto a peripheral location on the retina. This location is referred to as the preferred retinal locus (PRL). Although previous research has investigated the characteristics of this PRL, it is unclear whether eye movement metrics are modulated by peripheral viewing with a PRL as measured during a visual search paradigm. To this end, we tested four MD patients in a visual search paradigm and contrasted their performance with a healthy control group and a healthy control group performing the same experiment with a simulated scotoma. The experiment contained two conditions. In the first condition the target was an unfilled circle hidden among c-shaped distractors (serial condition) and in the second condition the target was a filled circle (pop-out condition). Saccadic search latencies for the MD group were significantly longer in both conditions compared to both control groups. Results of a subsequent experiment indicated that this difference between the MD and the control groups could not be explained by a difference in target selection sensitivity. Furthermore, search behavior of MD patients was associated with saccades with smaller amplitudes toward the scotoma, an increased intersaccadic interval and an increased number of eye movements necessary to locate the target. Some of these characteristics, such as the increased intersaccadic interval, were also observed in the simulation group, which indicate that these characteristics are related to the peripheral viewing itself. We suggest that the combination of the central scotoma and peripheral viewing can explain the altered search behavior and no behavioral evidence was found for a possible reorganization of the visual system associated with the use of a PRL. Thus the switch from a fovea-based to a PRL-based reference frame impairs search efficiency.

Perceived object stability depends on multisensory estimates of gravity.

PubMed

Barnett-Cowan, Michael; Fleming, Roland W; Singh, Manish; Bülthoff, Heinrich H

2011-04-27

How does the brain estimate object stability? Objects fall over when the gravity-projected centre-of-mass lies outside the point or area of support. To estimate an object's stability visually, the brain must integrate information across the shape and compare its orientation to gravity. When observers lie on their sides, gravity is perceived as tilted toward body orientation, consistent with a representation of gravity derived from multisensory information. We exploited this to test whether vestibular and kinesthetic information affect this visual task or whether the brain estimates object stability solely from visual information. In three body orientations, participants viewed images of objects close to a table edge. We measured the critical angle at which each object appeared equally likely to fall over or right itself. Perceived gravity was measured using the subjective visual vertical. The results show that the perceived critical angle was significantly biased in the same direction as the subjective visual vertical (i.e., towards the multisensory estimate of gravity). Our results rule out a general explanation that the brain depends solely on visual heuristics and assumptions about object stability. Instead, they suggest that multisensory estimates of gravity govern the perceived stability of objects, resulting in objects appearing more stable than they are when the head is tilted in the same direction in which they fall.

Visual Literacy. . .An Overview of Theory and Practice.

ERIC Educational Resources Information Center

DeSantis, Lucille Burbank; Pett, Dennis W.

Visual Literacy is a field that encompasses a variety of theoretical constructs and practical considerations relating to communicating with visual signs. The theoretical constructs that influence visual communication primarily fall into two closely interrelated categories: those that relate to the individuals involved in the communication process,…

Prevalence of vision loss among hospital in-patients; a risk factor for falls?

PubMed

Leat, Susan J; Zecevic, Aleksandra A; Keeling, Alexis; Hileeto, Denise; Labreche, Tammy; Brymer, Christopher

2018-01-01

Despite poor vision being a risk factor for falls, current hospital policies and practices often do not include a vision assessment at patient admission or in the hospital's incident reporting system when a fall occurs. Our purpose was to document the prevalence of vision loss in hospital general medicine units to increase awareness of poor vision as a potential risk factor for falls that occur within the hospital, and inform future preventative practice. This cross-sectional study took place in medicine units of an acute care hospital. Participants were adult in-patients. Visual acuity (VA), contrast sensitivity and stereoacuity were measured, and patients were screened for field loss, extinction and neglect. 115 participants took part (average age 67 ± 17, 48% female). Overall, 89% had a visual impairment defined as being outside the age-norms for one or more vision measure, 62% had low vision, and 36% had vision loss equivalent to legal blindness [VA equal to or poorer than 1.0 logMAR (6/60, 20/200) or ≥10x below age-norms]. There was a considerable discrepancy between the prevalence of low vision and the percentage of patients who reported an ocular diagnosis that would result in visual loss (30%). Ten patients fell during the study period, and of these 100% had visual impairment, 90% had low vision and 60% had vision loss equivalent to legal blindness, which compares to 58%, 22% and 9% for non-fallers. Similar high prevalences were found in those whose reason for admission to the hospital was a fall (92%, 63% and 33% respectively). Vision loss has a high prevalence among patients in hospital medicine units, and is higher still among those who fall. Since vision loss may be a contributing factor to falls that occur in hospitals, implementing an assessment of vision at hospital admission would be useful to alert staff to those patients who are at risk for falls due to poor vision, so that preventative measures can be applied. © 2017 The Authors Ophthalmic & Physiological Optics © 2017 The College of Optometrists.

The effect of sensorimotor training on the postural stability of visually impaired women over 50 years of age.

PubMed

Maćkowiak, Zuzanna; Osiński, Wieslaw; Salamon, Artur

2015-01-01

Previous studies indicated that blind and visually impaired people are a group with greater risk of falls. Postmenopausal changes significantly decrease physical efficiency and impair the body's mechanisms for maintaining postural stability. In addition, the frequency of falls among women is much higher than in men. The aim of this study was to analyze the effect of sensorimotor exercise on changes in postural stability of visually impaired women over 50 years of age. Visually impaired women from group E showed a lower level of postural stability measured with EO compared to the healthy women. After completing the exercise, a more pronounced improvement in the level of postural stability was observed in group E.

Fall prevention and monitoring of assisted living patients: an exploratory study of physician perspectives.

PubMed

Nyrop, Kirsten A; Zimmerman, Sheryl; Sloane, Philip D; Bangdiwala, Srikant

2012-06-01

Explore physician perspectives on their involvement in fall prevention and monitoring for residential care/assisted living (RC/AL) residents. Exploratory cross-sectional study; mailed questionnaire. Four RC/AL communities, North Carolina. Primary physicians for RC/AL residents. Past Behavior and future Intentions of physicians with regard to (1) fall risk assessment and (2) collaboration with RC/AL staff to reduce falls and fall risks among RC/AL residents were explored using Theory of Planned Behavior (TPB) constructs. Predictor variables examined (1) physicians' views on their own responsibilities (Attitude), (2) their views of expectations from important referent groups (Subjective Norms), and (3) perceived constraints on engaging in fall prevention and monitoring (Perceived Behavioral Control). Physicians reported conducting fall risk assessments of 47% of RC/AL patients and collaborating with RC/AL staff to reduce fall risks for 36% of RC/AL patients (Behavior). These proportions increased to 75% and 62%, respectively, for future Intentions. TPB-based models explained approximately 60% of the variance in self-reported Behavior and Intentions. Physician's involvement in fall prevention and monitoring was significantly associated (P < .05) with their perceptions of barriers and facilitators-ease, time, reimbursement, and expertise. This study provides first data on physician beliefs regarding their involvement in fall risk assessment of RC/AL patients and collaboration with RC/AL staff to reduce fall risks of individual patients. Challenges to physician involvement identified in our study are not unique or specific to the RC/AL setting, and instead relate to clinical practice and reimbursement constraints in general. Copyright © 2012 American Medical Directors Association, Inc. Published by Elsevier Inc. All rights reserved.

Gazing into Thin Air: The Dual-Task Costs of Movement Planning and Execution during Adaptive Gait

PubMed Central

Ellmers, Toby J.; Cocks, Adam J.; Doumas, Michail; Williams, A. Mark; Young, William R.

2016-01-01

We examined the effect of increased cognitive load on visual search behavior and measures of gait performance during locomotion. Also, we investigated how personality traits, specifically the propensity to consciously control or monitor movements (trait movement ‘reinvestment’), impacted the ability to maintain effective gaze under conditions of cognitive load. Healthy young adults traversed a novel adaptive walking path while performing a secondary serial subtraction task. Performance was assessed using correct responses to the cognitive task, gaze behavior, stepping accuracy, and time to complete the walking task. When walking while simultaneously carrying out the secondary serial subtraction task, participants visually fixated on task-irrelevant areas ‘outside’ the walking path more often and for longer durations of time, and fixated on task-relevant areas ‘inside’ the walkway for shorter durations. These changes were most pronounced in high-trait-reinvesters. We speculate that reinvestment-related processes placed an additional cognitive demand upon working memory. These increased task-irrelevant ‘outside’ fixations were accompanied by slower completion rates on the walking task and greater gross stepping errors. Findings suggest that attention is important for the maintenance of effective gaze behaviors, supporting previous claims that the maladaptive changes in visual search observed in high-risk older adults may be a consequence of inefficiencies in attentional processing. Identifying the underlying attentional processes that disrupt effective gaze behaviour during locomotion is an essential step in the development of rehabilitation, with this information allowing for the emergence of interventions that reduce the risk of falling. PMID:27824937

Neurons in the monkey amygdala detect eye-contact during naturalistic social interactions

PubMed Central

Mosher, Clayton P.; Zimmerman, Prisca E.; Gothard, Katalin M.

2014-01-01

Summary Primates explore the visual world through eye-movement sequences. Saccades bring details of interest into the fovea while fixations stabilize the image [1]. During natural vision, social primates direct their gaze at the eyes of others to communicate their own emotions and intentions and to gather information about the mental states of others [2]. Direct gaze is an integral part of facial expressions that signals cooperation or conflict over resources and social status [3-6]. Despite the great importance of making and breaking eye contact in the behavioral repertoire of primates, little is known about the neural substrates that support these behaviors. Here we show that the monkey amygdala contains neurons that respond selectively to fixations at the eyes of others and to eye contact. These “eye cells” share several features with the canonical, visually responsive neurons in the monkey amygdala, however, they respond to the eyes only when they fall within the fovea of the viewer, either as a result of a deliberate saccade, or as eyes move into the fovea of the viewer during a fixation intended to explore a different feature. The presence of eyes in peripheral vision fails to activate the eye cells. These findings link the primate amygdala to eye-movements involved in the exploration and selection of details in visual scenes that contain socially and emotionally salient features. PMID:25283782

Neurons in the monkey amygdala detect eye contact during naturalistic social interactions.

PubMed

Mosher, Clayton P; Zimmerman, Prisca E; Gothard, Katalin M

2014-10-20

Primates explore the visual world through eye-movement sequences. Saccades bring details of interest into the fovea, while fixations stabilize the image. During natural vision, social primates direct their gaze at the eyes of others to communicate their own emotions and intentions and to gather information about the mental states of others. Direct gaze is an integral part of facial expressions that signals cooperation or conflict over resources and social status. Despite the great importance of making and breaking eye contact in the behavioral repertoire of primates, little is known about the neural substrates that support these behaviors. Here we show that the monkey amygdala contains neurons that respond selectively to fixations on the eyes of others and to eye contact. These "eye cells" share several features with the canonical, visually responsive neurons in the monkey amygdala; however, they respond to the eyes only when they fall within the fovea of the viewer, either as a result of a deliberate saccade or as eyes move into the fovea of the viewer during a fixation intended to explore a different feature. The presence of eyes in peripheral vision fails to activate the eye cells. These findings link the primate amygdala to eye movements involved in the exploration and selection of details in visual scenes that contain socially and emotionally salient features. Copyright © 2014 Elsevier Ltd. All rights reserved.

Fall Risk Assessment and Early-Warning for Toddler Behaviors at Home

PubMed Central

Yang, Mau-Tsuen; Chuang, Min-Wen

2013-01-01

Accidental falls are the major cause of serious injuries in toddlers, with most of these falls happening at home. Instead of providing immediate fall detection based on short-term observations, this paper proposes an early-warning childcare system to monitor fall-prone behaviors of toddlers at home. Using 3D human skeleton tracking and floor plane detection based on depth images captured by a Kinect system, eight fall-prone behavioral modules of toddlers are developed and organized according to four essential criteria: posture, motion, balance, and altitude. The final fall risk assessment is generated by a multi-modal fusion using either a weighted mean thresholding or a support vector machine (SVM) classification. Optimizations are performed to determine local parameter in each module and global parameters of the multi-modal fusion. Experimental results show that the proposed system can assess fall risks and trigger alarms with an accuracy rate of 92% at a speed of 20 frames per second. PMID:24335727

Fall risk assessment and early-warning for toddler behaviors at home.

PubMed

Yang, Mau-Tsuen; Chuang, Min-Wen

2013-12-10

Accidental falls are the major cause of serious injuries in toddlers, with most of these falls happening at home. Instead of providing immediate fall detection based on short-term observations, this paper proposes an early-warning childcare system to monitor fall-prone behaviors of toddlers at home. Using 3D human skeleton tracking and floor plane detection based on depth images captured by a Kinect system, eight fall-prone behavioral modules of toddlers are developed and organized according to four essential criteria: posture, motion, balance, and altitude. The final fall risk assessment is generated by a multi-modal fusion using either a weighted mean thresholding or a support vector machine (SVM) classification. Optimizations are performed to determine local parameter in each module and global parameters of the multi-modal fusion. Experimental results show that the proposed system can assess fall risks and trigger alarms with an accuracy rate of 92% at a speed of 20 frames per second.

GPU-Based Interactive Exploration and Online Probability Maps Calculation for Visualizing Assimilated Ocean Ensembles Data

NASA Astrophysics Data System (ADS)

Hoteit, I.; Hollt, T.; Hadwiger, M.; Knio, O. M.; Gopalakrishnan, G.; Zhan, P.

2016-02-01

Ocean reanalyses and forecasts are nowadays generated by combining ensemble simulations with data assimilation techniques. Most of these techniques resample the ensemble members after each assimilation cycle. Tracking behavior over time, such as all possible paths of a particle in an ensemble vector field, becomes very difficult, as the number of combinations rises exponentially with the number of assimilation cycles. In general a single possible path is not of interest but only the probabilities that any point in space might be reached by a particle at some point in time. We present an approach using probability-weighted piecewise particle trajectories to allow for interactive probability mapping. This is achieved by binning the domain and splitting up the tracing process into the individual assimilation cycles, so that particles that fall into the same bin after a cycle can be treated as a single particle with a larger probability as input for the next cycle. As a result we loose the possibility to track individual particles, but can create probability maps for any desired seed at interactive rates. The technique is integrated in an interactive visualization system that enables the visual analysis of the particle traces side by side with other forecast variables, such as the sea surface height, and their corresponding behavior over time. By harnessing the power of modern graphics processing units (GPUs) for visualization as well as computation, our system allows the user to browse through the simulation ensembles in real-time, view specific parameter settings or simulation models and move between different spatial or temporal regions without delay. In addition our system provides advanced visualizations to highlight the uncertainty, or show the complete distribution of the simulations at user-defined positions over the complete time series of the domain.

Foremen’s Intervention to Prevent Falls and Increase Safety Communication at Residential Construction Sites

PubMed Central

Kaskutas, Vicki; Buckner-Petty, Skye; Dale, Ann Marie; Gaal, John; Evanoff, Bradley A.

2017-01-01

Background This research aimed to improve residential construction foremen’s communication skills and safety behaviors of their crewmembers when working at heights. Methods Eighty-four residential construction foremen participated in the 8-hour fall prevention and safety communication training. We compared pre-intervention surveys from foremen and their crewmembers to measure the effect of training. Results Foremen and crewmembers’ ratings showed improvements in fall prevention knowledge, behaviors, and safety communication and were sustained 6-months post-training, with emphasized areas demonstrating larger increases. Ratings were similar between foremen and crewmembers, suggesting that the foremen effectively taught their crew and assigned accurate ratings. Based upon associations between safety behaviors and reported falls observed in prior research, we would expect a 16.6% decrease in the one year cumulative incidence of self-reported falls post-intervention. Conclusions This intervention improved safety knowledge and behaviors of a large number of workers by training construction foremen in fall prevention and safety communication skills. PMID:27345465

Mobility performance in glaucoma.

PubMed

Turano, K A; Rubin, G S; Quigley, H A

1999-11-01

To determine whether glaucoma affects mobility performance and whether there is a relationship between mobility performance and stage of disease as estimated from vision-function measures. The mobility performance of 47 glaucoma subjects was compared with that of 47 normal-vision subjects who were of similar age. Mobility performance was assessed by the time required to complete an established travel path and the number of mobility incidents. The subjective assessment of falling and fear of falling were also compared. Vision function was assessed by measures of visual acuity, contrast sensitivity, monocular automated threshold perimetry, and suprathreshold; binocular visual fields were assessed with the Esterman test. The glaucoma subjects walked on average 10% more slowly than did the normal-vision subjects. The number of people who experienced bumps, stumbles, or orientation problems was almost twice as high in the glaucoma group than the normal-vision group, but the difference did not reach statistical significance. The difference between groups also was not significant with respect to the number of people who reported falling in the past year (38% for the glaucoma group and 30% for the normal-vision group) or a fear of falling (28% for the glaucoma group and 23% for the normal-vision group). The visual fields assessed with a Humphrey 24-2 test were more highly correlated with walking speed in glaucoma than the visual fields scored by the Esterman scale or than visual acuity or contrast sensitivity. Glaucoma is associated with a modest decrease in mobility performance. Walking speed decreases with severity of the disease as estimated by threshold perimetry.

Fall Prediction and Prevention Systems: Recent Trends, Challenges, and Future Research Directions.

PubMed

Rajagopalan, Ramesh; Litvan, Irene; Jung, Tzyy-Ping

2017-11-01

Fall prediction is a multifaceted problem that involves complex interactions between physiological, behavioral, and environmental factors. Existing fall detection and prediction systems mainly focus on physiological factors such as gait, vision, and cognition, and do not address the multifactorial nature of falls. In addition, these systems lack efficient user interfaces and feedback for preventing future falls. Recent advances in internet of things (IoT) and mobile technologies offer ample opportunities for integrating contextual information about patient behavior and environment along with physiological health data for predicting falls. This article reviews the state-of-the-art in fall detection and prediction systems. It also describes the challenges, limitations, and future directions in the design and implementation of effective fall prediction and prevention systems.

Vision and agility training in community dwelling older adults: incorporating visual training into programs for fall prevention.

PubMed

Reed-Jones, Rebecca J; Dorgo, Sandor; Hitchings, Maija K; Bader, Julia O

2012-04-01

This study aimed to examine the effect of visual training on obstacle course performance of independent community dwelling older adults. Agility is the ability to rapidly alter ongoing motor patterns, an important aspect of mobility which is required in obstacle avoidance. However, visual information is also a critical factor in successful obstacle avoidance. We compared obstacle course performance of a group that trained in visually driven body movements and agility drills, to a group that trained only in agility drills. We also included a control group that followed the American College of Sports Medicine exercise recommendations for older adults. Significant gains in fitness, mobility and power were observed across all training groups. Obstacle course performance results revealed that visual training had the greatest improvement on obstacle course performance (22%) following a 12 week training program. These results suggest that visual training may be an important consideration for fall prevention programs. Copyright © 2011 Elsevier B.V. All rights reserved.

Behavioral self-concept as predictor of teen drinking behaviors.

PubMed

Dudovitz, Rebecca N; Li, Ning; Chung, Paul J

2013-01-01

Adolescence is a critical developmental period for self-concept (role identity). Cross-sectional studies link self-concept's behavioral conduct domain (whether teens perceive themselves as delinquent) with adolescent substance use. If self-concept actually drives substance use, then it may be an important target for intervention. In this study, we used longitudinal data from 1 school year to examine whether behavioral self-concept predicts teen drinking behaviors or vice versa. A total of 291 students from a large, predominantly Latino public high school completed a confidential computerized survey in the fall and spring of their 9th grade year. Survey measures included the frequency of alcohol use, binge drinking and at-school alcohol use in the previous 30 days; and the Harter Self-Perception Profile for Adolescents behavioral conduct subscale. Multiple regressions were performed to test whether fall self-concept predicted the frequency and type of spring drinking behavior, and whether the frequency and type of fall drinking predicted spring self-concept. Fall behavioral self-concept predicted both the frequency and type of spring drinking. Students with low versus high fall self-concept had a predicted probability of 31% versus 20% for any drinking, 20% versus 8% for binge drinking and 14% versus 4% for at-school drinking in the spring. However, neither the frequency nor the type of fall drinking significantly predicted spring self-concept. Low behavioral self-concept may precede or perhaps even drive adolescent drinking. If these results are confirmed, then prevention efforts might be enhanced by targeting high-risk teens for interventions that help develop a healthy behavioral self-concept. Copyright © 2013 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

Neighborhood walkability, fear and risk of falling and response to walking promotion: The Easy Steps to Health 12-month randomized controlled trial.

PubMed

Merom, D; Gebel, K; Fahey, P; Astell-Burt, T; Voukelatos, A; Rissel, C; Sherrington, C

2015-01-01

In older adults the relationships between health, fall-related risk factors, perceived neighborhood walkability, walking behavior and intervention impacts are poorly understood. To determine whether: i) health and fall-related risk factors were associated with perceptions of neighborhood walkability; ii) perceived environmental attributes, and fall-related risk factors predicted change in walking behavior at 12 months; and iii) perceived environmental attributes and fall-related risk factors moderated the effect of a self-paced walking program on walking behavior. Randomized trial on walking and falls conducted between 2009 and 2012 involving 315 community-dwelling inactive adults ≥ 65 years living in Sydney, Australia. Measures were: mobility status, fall history, injurious fall and fear of falling (i.e., fall-related risk factors), health status, walking self-efficacy and 11 items from the neighborhood walkability scale and planned walking ≥ 150 min/week at 12 months. Participants with poorer mobility, fear of falling, and poor health perceived their surroundings as less walkable. Walking at 12 months was significantly greater in "less greenery" (AOR = 3.3, 95% CI: 1.11-9.98) and "high traffic" (AOR = 1.98, 95% CI: 1.00-3.91) neighborhoods. The intervention had greater effects in neighborhoods perceived to have poorer pedestrian infrastructure (p for interaction = 0.036). Low perceived walkability was shaped by health status and did not appear to be a barrier to walking behavior. There appears to be a greater impact of, and thus, need for, interventions to encourage walking in environments perceived not to have supportive walking infrastructure. Future studies on built environments and walking should gather information on fall-related risk factors to better understand how these characteristics interact.

A standing posture is associated with increased susceptibility to the sound-induced flash illusion in fall-prone older adults.

PubMed

Stapleton, John; Setti, Annalisa; Doheny, Emer P; Kenny, Rose Anne; Newell, Fiona N

2014-02-01

Recent research has provided evidence suggesting a link between inefficient processing of multisensory information and incidence of falling in older adults. Specifically, Setti et al. (Exp Brain Res 209:375-384, 2011) reported that older adults with a history of falling were more susceptible than their healthy, age-matched counterparts to the sound-induced flash illusion. Here, we investigated whether balance control in fall-prone older adults was directly associated with multisensory integration by testing susceptibility to the illusion under two postural conditions: sitting and standing. Whilst standing, fall-prone older adults had a greater body sway than the age-matched healthy older adults and their body sway increased when presented with the audio-visual illusory but not the audio-visual congruent conditions. We also found an increase in susceptibility to the sound-induced flash illusion during standing relative to sitting for fall-prone older adults only. Importantly, no performance differences were found across groups in either the unisensory or non-illusory multisensory conditions across the two postures. These results suggest an important link between multisensory integration and balance control in older adults and have important implications for understanding why some older adults are prone to falling.

Fall Prevention in Apprentice Carpenters

PubMed Central

Kaskutas, Vicki; Dale, Ann Marie; Lipscomb, Hester; Gaal, John; Fuchs, Mark; Evanoff, Bradley; Faucette, Julia; Gillen, Marion; Deych, Elena

2013-01-01

Objectives Falls from heights are a leading cause of mortality and morbidity in the construction industry, especially among inexperienced workers. We surveyed apprentice carpenters to identify individual and organizational factors associated with falls from heights. Methods We developed a 72-item fall prevention survey with multiple domains including fall experience, fall prevention knowledge, risk perceptions, confidence in ability to prevent falls, training experience, and perceptions of the safety climate and crew safety behaviors. We administered the questionnaire to apprentice carpenters in this cross-sectional study. Results Of the 1,025 respondents, 51% knew someone who had fallen from height at work and 16% had personally fallen in the past year, with ladders accounting for most of the falls. Despite participation in school-based and on-the-job training, fall prevention knowledge was poor. Ladders were perceived as low risk and ladder training was rare. Apprentices reported high levels of unsafe fall-related behaviors on their work crews. Apprentices working residential construction were more likely to fall than those working commercial construction, as were apprentices working on crews with fewer senior carpenters to provide mentorship, and those reporting more unsafe behaviors among fellow workers. Conclusions Despite participation in a formal apprenticeship program, many apprentices work at heights without adequate preparation and subsequently experience falls. Apprenticeship programs can improve the timing and content of fall prevention training. This study suggests that organizational changes in building practices, mentorship, and safety culture must also occur in order to decrease worker falls from heights. PMID:19953214

Audio–visual interactions for motion perception in depth modulate activity in visual area V3A

PubMed Central

Ogawa, Akitoshi; Macaluso, Emiliano

2013-01-01

Multisensory signals can enhance the spatial perception of objects and events in the environment. Changes of visual size and auditory intensity provide us with the main cues about motion direction in depth. However, frequency changes in audition and binocular disparity in vision also contribute to the perception of motion in depth. Here, we presented subjects with several combinations of auditory and visual depth-cues to investigate multisensory interactions during processing of motion in depth. The task was to discriminate the direction of auditory motion in depth according to increasing or decreasing intensity. Rising or falling auditory frequency provided an additional within-audition cue that matched or did not match the intensity change (i.e. intensity-frequency (IF) “matched vs. unmatched” conditions). In two-thirds of the trials, a task-irrelevant visual stimulus moved either in the same or opposite direction of the auditory target, leading to audio–visual “congruent vs. incongruent” between-modalities depth-cues. Furthermore, these conditions were presented either with or without binocular disparity. Behavioral data showed that the best performance was observed in the audio–visual congruent condition with IF matched. Brain imaging results revealed maximal response in visual area V3A when all cues provided congruent and reliable depth information (i.e. audio–visual congruent, IF-matched condition including disparity cues). Analyses of effective connectivity revealed increased coupling from auditory cortex to V3A specifically in audio–visual congruent trials. We conclude that within- and between-modalities cues jointly contribute to the processing of motion direction in depth, and that they do so via dynamic changes of connectivity between visual and auditory cortices. PMID:23333414

Effects of the visual-feedback-based force platform training with functional electric stimulation on the balance and prevention of falls in older adults: a randomized controlled trial.

PubMed

Li, Zhen; Wang, Xiu-Xia; Liang, Yan-Yi; Chen, Shu-Yan; Sheng, Jing; Ma, Shao-Jun

2018-01-01

Force platform training with functional electric stimulation aimed at improving balance may be effective in fall prevention for older adults. Aim of the study is to evaluate the effects of the visual-feedback-based force platform balance training with functional electric stimulation on balance and fall prevention in older adults. A single-centre, unblinded, randomized controlled trial was conducted. One hundred and twenty older adults were randomly allocated to two groups: the control group ( n  = 60, one-leg standing balance exercise, 12 min/d) or the intervention group ( n  = 60, force platform training with functional electric stimulation, 12 min/d). The training was provided 15 days a month for 3 months by physical therapists. Medial-lateral and anterior-posterior maximal range of sway with eyes open and closed, the Berg Balance Scale, the Barthel Index, the Falls Efficacy scale-International were assessed at baseline and after the 3-month intervention. A fall diary was kept by each participant during the 6-month follow-up. On comparing the two groups, the intervention group showed significantly decreased ( p  < 0.01) medial-lateral and anterior-posterior maximal range of sway with eyes open and closed. There was significantly higher improvement in the Berg Balance Scale ( p  < 0.05), the Barthel Index ( p  < 0.05) and the Falls Efficacy Scale-International ( p  < 0.05), along with significantly lesser number of injurious fallers ( p  < 0.05), number of fallers ( p  < 0.05), and fall rates ( p  < 0.05) during the 6-month follow-up in the intervention group. This study showed that the visual feedback-based force platform training with functional electric stimulation improved balance and prevented falls in older adults.

Internal models and prediction of visual gravitational motion.

PubMed

Zago, Myrka; McIntyre, Joseph; Senot, Patrice; Lacquaniti, Francesco

2008-06-01

Baurès et al. [Baurès, R., Benguigui, N., Amorim, M.-A., & Siegler, I. A. (2007). Intercepting free falling objects: Better use Occam's razor than internalize Newton's law. Vision Research, 47, 2982-2991] rejected the hypothesis that free-falling objects are intercepted using a predictive model of gravity. They argued instead for "a continuous guide for action timing" based on visual information updated till target capture. Here we show that their arguments are flawed, because they fail to consider the impact of sensori-motor delays on interception behaviour and the need for neural compensation of such delays. When intercepting a free-falling object, the delays can be overcome by a predictive model of the effects of gravity on target motion.

Foremen's intervention to prevent falls and increase safety communication at residential construction sites.

PubMed

Kaskutas, Vicki; Buckner-Petty, Skye; Dale, Ann Marie; Gaal, John; Evanoff, Bradley A

2016-10-01

This research aimed to improve residential construction foremen's communication skills and safety behaviors of their crewmembers when working at heights. Eighty-four residential construction foremen participated in the 8-hr fall prevention and safety communication training. We compared pre- and post-intervention surveys from foremen and their crewmembers to measure the effect of training. Foremen and crewmembers' ratings showed improvements in fall prevention knowledge, behaviors, and safety communication and were sustained 6-months post-training, with emphasized areas demonstrating larger increases. Ratings were similar between foremen and crewmembers, suggesting that the foremen effectively taught their crew and assigned accurate ratings. Based upon associations between safety behaviors and reported falls observed in prior research, we would expect a 16.6% decrease in the one year cumulative incidence of self-reported falls post-intervention. This intervention improved safety knowledge and behaviors of a large number of workers by training construction foremen in fall prevention and safety communication skills. Am. J. Ind. Med. 59:823-831, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Prosocial Behavior Moderates the Effects of Aggression on Young Adolescents' Friendships

ERIC Educational Resources Information Center

McDonald, Kristina L.; Wang, Jennifer; Menzer, Melissa M.; Rubin, Kenneth H.; Booth-LaForce, Cathryn

2011-01-01

The current study explored how prosocial behavior may moderate how aggression is related to the features of adolescents' friendships. Young adolescents (N = 910) completed friendship nominations in the fall and spring of their first year of middle school. Behavioral nominations of aggression and prosocial behavior were also collected in the fall.…

Fall Prediction and Prevention Systems: Recent Trends, Challenges, and Future Research Directions

PubMed Central

Rajagopalan, Ramesh; Jung, Tzyy-Ping

2017-01-01

Fall prediction is a multifaceted problem that involves complex interactions between physiological, behavioral, and environmental factors. Existing fall detection and prediction systems mainly focus on physiological factors such as gait, vision, and cognition, and do not address the multifactorial nature of falls. In addition, these systems lack efficient user interfaces and feedback for preventing future falls. Recent advances in internet of things (IoT) and mobile technologies offer ample opportunities for integrating contextual information about patient behavior and environment along with physiological health data for predicting falls. This article reviews the state-of-the-art in fall detection and prediction systems. It also describes the challenges, limitations, and future directions in the design and implementation of effective fall prediction and prevention systems. PMID:29104256

Predictors of Visualization: A Structural Equation Model.

ERIC Educational Resources Information Center

Robichaux, Rebecca R.; Guarino, A. J.

This study tested a causal model of the development of spatial visualization based on a synthesis of past and present research. During the summer and fall of 1999, 117 third- and fourth-year undergraduates majoring in architecture, mathematics, mathematics education, and mechanical engineering completed a spatial visualization test and a…

Older adult falls prevention behaviors 60 days post-discharge from an urban emergency department after treatment for a fall.

PubMed

Shankar, Kalpana Narayan; Treadway, Nicole J; Taylor, Alyssa A; Breaud, Alan H; Peterson, Elizabeth W; Howland, Jonathan

2017-12-01

Falls are a common and debilitating health problem for older adults. Older adults are often treated and discharged home by emergency department (ED)-based providers with the hope they will receive falls prevention resources and referrals from their primary care provider. This descriptive study investigated falls prevention activities, including interactions with primary care providers, among community-dwelling older adults who were discharged home after presenting to an ED with a fall-related injury. We enrolled English speaking patients, aged ≥ 65 years, who presented to the ED of an urban level one trauma center with a fall or fall related injury and discharged home. During subjects' initial visits to the ED, we screened and enrolled patients, gathered patient demographics and provided them with a flyer for a Matter of Balance course. Sixty-days post enrollment, we conducted a phone follow-up interview to collect information on post-fall behaviors including information regarding the efforts to engage family and the primary care provider, enroll in a falls prevention program, assess patients' attitudes towards falling and experiences with any subsequent falls. Eighty-seven community-dwelling people between the ages of 65 and 90 were recruited, the majority (76%) being women. Seventy-one percent of subjects reported talking to their provider regarding the fall; 37% reported engaging in falls prevention activities. No subjects reported enrolling in a fall prevention program although two reported contacting falls program staff. Fourteen percent of subjects (n=12) reported a recurrent fall and 8% (7) reported returning to the ED after a recurrent fall. Findings indicate a low rate of initiating fall prevention behaviors following an ED visit for a fall-related injury among community-dwelling older adults, and highlight the ED visit as an important, but underutilized, opportunity to mobilize health care resources for people at high risk for subsequent falls.

Analysis of the free-fall behavior of liquid-metal drops in a gaseous atmosphere

NASA Technical Reports Server (NTRS)

Mccoy, J. Kevin; Markworth, Alan J.; Collings, E. W.; Brodkey, Robert S.

1987-01-01

The free-fall of a liquid-metal drop and heat transfer from the drop to its environment are described for both a gaseous atmosphere and vacuum. A simple model, in which the drop is assumed to fall rectilinearly with behavior like that of a rigid particle, is developed first, then possible causes of deviation from this behavior are discussed. The model is applied to describe solidification of drops in a drop tube. Possible future developments of the model are suggested.

The corrosion behavior of technetium metal exposed to aqueous sulfate and chloride solutions

DOE PAGES

Kolman, David Gary; Goff, George Scott; Cisneros, Michael Ruben; ...

2017-04-19

Here, metal waste forms are being studied as possible disposal forms for technetium and other fission products from spent nuclear fuel. As an initial step in assessing the viability of waste forms, technetium corrosion and passivity behavior was assessed across a broad pH spectrum (pH –1 to pH 13). Measurements indicate that the open circuit potential falls into the region of Tc +7 stability, more noble than the region of presumed passivity. Potentiodynamic polarization tests indicate that the Tc samples are not passive. Both electrochemical results and visual inspection suggest the presence of a nonprotective film. The corrosion rate ismore » relatively independent of pH and low, as measured by linear polarization resistance. No evidence of passivity was observed in the Tc +4 region of the potential-pH diagram following in-situ abrasion, suggesting that Tc does not passivate, regardless of potential.« less

The corrosion behavior of technetium metal exposed to aqueous sulfate and chloride solutions

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

Kolman, David Gary; Goff, George Scott; Cisneros, Michael Ruben

Here, metal waste forms are being studied as possible disposal forms for technetium and other fission products from spent nuclear fuel. As an initial step in assessing the viability of waste forms, technetium corrosion and passivity behavior was assessed across a broad pH spectrum (pH –1 to pH 13). Measurements indicate that the open circuit potential falls into the region of Tc +7 stability, more noble than the region of presumed passivity. Potentiodynamic polarization tests indicate that the Tc samples are not passive. Both electrochemical results and visual inspection suggest the presence of a nonprotective film. The corrosion rate ismore » relatively independent of pH and low, as measured by linear polarization resistance. No evidence of passivity was observed in the Tc +4 region of the potential-pH diagram following in-situ abrasion, suggesting that Tc does not passivate, regardless of potential.« less

Vision and falls in older people: risk factors and intervention strategies.

PubMed

Lord, Stephen R; Smith, Stuart T; Menant, Jasmine C

2010-11-01

Poor vision impairs balance and increases the risk of falls and fractures in older people. Multifocal glasses can add to this risk by impairing contrast sensitivity, depth perception, and ability to negotiate obstacles. Vision assessment and provision of new spectacles may not reduce, and may even increase, the risk of falls. Restriction of the use of multifocal glasses may reduce falls in active older people. Other effective fall prevention strategies include maximizing vision through cataract surgery and occupational therapy interventions in visually impaired older people. Copyright © 2010 Elsevier Inc. All rights reserved.

The Role of Cognitive Factors in Predicting Balance and Fall Risk in a Neuro-Rehabilitation Setting.

PubMed

Saverino, A; Waller, D; Rantell, K; Parry, R; Moriarty, A; Playford, E D

2016-01-01

There is a consistent body of evidence supporting the role of cognitive functions, particularly executive function, in the elderly and in neurological conditions which become more frequent with ageing. The aim of our study was to assess the role of different domains of cognitive functions to predict balance and fall risk in a sample of adults with various neurological conditions in a rehabilitation setting. This was a prospective, cohort study conducted in a single centre in the UK. 114 participants consecutively admitted to a Neuro-Rehabilitation Unit were prospectively assessed for fall accidents. Baseline assessment included a measure of balance (Berg Balance Scale) and a battery of standard cognitive tests measuring executive function, speed of information processing, verbal and visual memory, visual perception and intellectual function. The outcomes of interest were the risk of becoming a faller, balance and fall rate. Two tests of executive function were significantly associated with fall risk, the Stroop Colour Word Test (IRR 1.01, 95% CI 1.00-1.03) and the number of errors on part B of the Trail Making Test (IRR 1.23, 95% CI 1.03-1.49). Composite scores of executive function, speed of information processing and visual memory domains resulted in 2 to 3 times increased likelihood of having better balance (OR 2.74 95% CI 1.08 to 6.94, OR 2.72 95% CI 1.16 to 6.36 and OR 2.44 95% CI 1.11 to 5.35 respectively). Our results show that specific subcomponents of executive functions are able to predict fall risk, while a more global cognitive dysfunction is associated with poorer balance.

The Role of Cognitive Factors in Predicting Balance and Fall Risk in a Neuro-Rehabilitation Setting

PubMed Central

Saverino, A.; Waller, D.; Rantell, K.; Parry, R.; Moriarty, A.; Playford, E. D.

2016-01-01

Introduction There is a consistent body of evidence supporting the role of cognitive functions, particularly executive function, in the elderly and in neurological conditions which become more frequent with ageing. The aim of our study was to assess the role of different domains of cognitive functions to predict balance and fall risk in a sample of adults with various neurological conditions in a rehabilitation setting. Methods This was a prospective, cohort study conducted in a single centre in the UK. 114 participants consecutively admitted to a Neuro-Rehabilitation Unit were prospectively assessed for fall accidents. Baseline assessment included a measure of balance (Berg Balance Scale) and a battery of standard cognitive tests measuring executive function, speed of information processing, verbal and visual memory, visual perception and intellectual function. The outcomes of interest were the risk of becoming a faller, balance and fall rate. Results Two tests of executive function were significantly associated with fall risk, the Stroop Colour Word Test (IRR 1.01, 95% CI 1.00–1.03) and the number of errors on part B of the Trail Making Test (IRR 1.23, 95% CI 1.03–1.49). Composite scores of executive function, speed of information processing and visual memory domains resulted in 2 to 3 times increased likelihood of having better balance (OR 2.74 95% CI 1.08 to 6.94, OR 2.72 95% CI 1.16 to 6.36 and OR 2.44 95% CI 1.11 to 5.35 respectively). Conclusions Our results show that specific subcomponents of executive functions are able to predict fall risk, while a more global cognitive dysfunction is associated with poorer balance. PMID:27115880

People with stroke living in the community: Attention deficits, balance, ADL ability and falls.

PubMed

Hyndman, D; Ashburn, A

2003-08-05

To describe levels of attention deficits among people with stroke living in the community and explore relationships between attention, balance, function and falls. Forty-eight mobile community-dwelling people with stroke (30 men, 18 women, mean age 68.4 +/- 11.2) were recruited to this cross-sectional investigation through General Practitioners. Twenty-six participants had a right, 21 a left hemisphere infarction and one had a brain stem lesion; mean time since stroke was 46 months (range five to 204). Participants' were interviewed about fall-events; attention, balance and function were assessed using standardised tests. Visual inattention was identified in five participants (10%), deficits of sustained attention in 15 (31%), auditory selective attention in nine (19%), visual selective attention in 17 (35%) and divided attention deficits in 21 participants (43%). Sustained and divided attention scores correlated with balance, ADL ability and fall-status (p < 0.01). The balance and function of subjects with normal attention were better than those with abnormal scores (p < 0.01). Analysis of variance revealed differences between repeat-fallers and non-fallers with no near-falls for divided attention, balance and ADL ability (p < 0.01). Attention deficits were common among this sample; sustained and divided attention deficits correlated with functional impairments and falls, highlighting that attention deficits might contribute to accident prone behaviour and falling.

[Managing concerns about falls in older people: evaluation of the implementation of an evidence-based program].

PubMed

Zijlstra, G A R; Du Moulin, M F M T; van Haastregt, J C M; de Jonge, M; Kempen, G I J M; van der Poel, A

2013-12-01

A cognitive behavioral program reduced concerns about falling and related avoidance behavior among older community-dwelling adults in a randomized controlled trial. In the current study we examined the effects and acceptability of the program after nation-wide implementation into home care organizations in The Netherlands. In a one-group pretest-posttest study with data collection before the start of the program and at 2 and 4 months, the effects and acceptability of the program were assessed in 125 community-dwelling older people. The outcomes of the effect evaluation included concerns about falls, related avoidance behavior, falls, fall-related medical attention, feelings of anxiety, symptoms of depression, and loneliness. Pretest-posttest analyses with the Wilcoxon signed-rank test and the paired t-test showed significant improvements at 4 months for concerns about falls, activity avoidance, number of falls in the past 2 months, feelings of anxiety, and symptoms of depression. No significant differences were shown for the other outcomes. After implementation in home care organizations, the outcomes indicate positive program effects on concerns about falls, avoidance behavior, and falls in community-dwelling older people. Given the similarity in results, i.e. between those of the previously performed randomized controlled trial and those of the current pretest-posttest study, we conclude that the program can be successfully implemented in practice. This article is an adjusted, Dutch version of Zijlstra GA, van Haastregt JC, Du Moulin MF, de Jonge MC, van der Poel A, Kempen GI. Effects of the implementation of an evidenc-based program to manage concerns about falls in older adults. The Gerontologist 2013;53(5):839-849; doi: 10.1093/geront/gns142.

The Knowing Eye: An Applied Arts Approach to Visual Knowledge.

ERIC Educational Resources Information Center

Barnhurst, Kevin G.

Since visual knowledge of the specialties within graphics and photography is difficult to pinpoint because it is nonverbal and intuitive, graphics educators fall back on teaching technical expertise--the procedures and equipment used for newspapers, magazines, and television stations. For centuries visual knowledge was the realm of the unlettered,…

Active Learning in Neuroscience: A Manipulative to Simulate Visual Field Defects

ERIC Educational Resources Information Center

Li, Andrew Yue-Lin; Carvalho, Helena

2016-01-01

Prevalent in 20-57% of stroke patients, visual field defects have been shown to impact quality of life. Studies have shown increased risk of falling, ambulatory difficulties, impaired reading ability, and feelings of panic in crowded or unfamiliar places in patients with visual field defects. Rehabilitation, independence, and mental health may…

Daily Routines and Sleep Disorders in Visually Impaired Children.

ERIC Educational Resources Information Center

Troster, Heinrich; And Others

1996-01-01

Assessed sleep disorders in 265 visually impaired and 67 non-disabled 10- to 72-month olds. Found that infants with visual impairments had more difficulties in falling asleep and in sleeping through the night than nonhandicapped children. Also found a relationship between sleep disorders and the regularity of children's daily routine and…

Falls prevention advice and visual feedback to those at risk of falling: study protocol for a pilot randomized controlled trial

PubMed Central

2013-01-01

Background Studies have shown that functional strength and balance exercises can reduce the risk of falling in older people if they are done on a regular basis. However, the repetitive nature of these exercises; combined with the inherent lack of feedback of progress may discourage seniors from exercising in the home, thereby rendering such an intervention ineffective. This study hypothesizes that the use of visual feedback and multimodal games will be more effective in encouraging adherence to home rehabilitation than standard care; thereby promoting independence and improving the quality of life in older adults at risk of falling. Methods A pllel-group pilot randomized controlled trial with 3 groups of participants will be conducted in the home for 12 weeks. Participants will include older adults who have been identified as at risk of falling (n = 48), over the age of 65, living in the community, and suitable for a home exercise intervention. The primary outcome is adherence to exercise. Secondary outcomes include: variability in stride length, stride time and double support time (DST); walking speed; Timed up and go test (TUG); Falls Efficacy Scale International (FES-I); CONFbal scale; Romberg’s test; and quality of life measures (SF-12 and EuroQol EQ-5D). Qualitative assessments on personal experiences with rehabilitation tools will be done before and after the trial. Discussion This study will investigate the use of visual feedback and engaging multimodal activities to address the problem of non-compliance to home exercises for falls rehabilitation. One of the unique qualities of this study is the adaptation of special participatory design methods through which the end users (fallers) will be involved in the design of the proposed rehabilitation tools at various stages of the design process. Trial registration ISRCTN79967470 PMID:23510162

Falls From Agricultural Machinery: Risk Factors Related to Work Experience, Worked Hours, and Operators' Behavior.

PubMed

Caffaro, Federica; Roccato, Michele; Micheletti Cremasco, Margherita; Cavallo, Eugenio

2018-02-01

Objective We investigated the risk factors for falls when egressing from agricultural tractors, analyzing the role played by worked hours, work experience, operators' behavior, and near misses. Background Many accidents occur within the agricultural sector each year. Among them, falls while dismounting the tractor represent a major source of injuries. Previous studies pointed out frequent hazardous movements and incorrect behaviors adopted by operators to exit the tractor cab. However, less is known about the determinants of such behaviors. In addition, near misses are known to be important predictors of accidents, but they have been under-investigated in the agricultural sector in general and as concerns falls in particular. Method A questionnaire assessing dismounting behaviors, previous accidents and near misses, and participants' relation with work was administered to a sample of Italian tractor operators ( n = 286). Results A mediated model showed that worked hours increase unsafe behaviors, whereas work experience decreases them. Unsafe behaviors in turn show a positive association with accidents, via the mediation of near misses. Conclusions We gave a novel contribution to the knowledge of the chain of events leading to fall accidents in the agricultural sector, which is one of the most hazardous industries. Applications Besides tractor design improvements, preventive training interventions may focus on the redesign of the actual working strategies and the adoption of engaging training methods in the use of machinery to optimize the learning of safety practices and safe behaviors.

Manneristic behaviors of visually impaired children.

PubMed

Molloy, Alysha; Rowe, Fiona J

2011-09-01

To review the literature on visual impairment in children in order to determine which manneristic behaviors are associated with visual impairment, and to establish why these behaviors occur and whether severity of visual impairment influences these behaviors. A literature search utilizing PubMed, OVID, Google Scholar, and Web of Knowledge databases was performed. The University of Liverpool ( www.liv.ac.uk/orthoptics/research ) and local library facilities were also searched. The main manneristic or stereotypic behaviors associated with visual impairment are eye-manipulatory behaviors, such as eye poking and rocking. The degree of visual impairment influences the type of behavior exhibited by visually impaired children. Totally blind children are more likely to adopt body and head movements whereas sight-impaired children tend to adopt eye-manipulatory behaviors and rocking. The mannerisms exhibited most frequently are those that provide a specific stimulation to the child. Theories to explain these behaviors include behavioral, developmental, functional, and neurobiological approaches. Although the precise etiology of these behaviors is unknown, it is recognized that each of the theories is useful in providing some explanation of why certain behaviors may occur. The age at which the frequency of these behaviors decreases is associated with the child's increasing development, thus those visually impaired children with additional disabilities, whose development is impaired, are at an increased risk of developing and maintaining these behaviors. Certain manneristic behaviors of the visually impaired child may also help indicate the cause of visual impairment. There is a wide range of manneristic behaviors exhibited by visually impaired children. Some of these behaviors appear to be particularly associated with certain causes of visual impairment or severity of visual impairment, thus they may supply the practitioner with useful information. Further research into the prevalence of these behaviors in the visually impaired child is required in order to provide effective management.

Body mass index, falls, and injurious falls among U.S. adults: Findings from the 2014 Behavioral Risk Factor Surveillance System.

PubMed

Ylitalo, Kelly R; Karvonen-Gutierrez, Carrie A

2016-10-01

Falls are an important health concern because they are associated with loss of independence and disability, particularly among women. We determined the age- and sex-specific prevalence of injurious falls among adults in the United States and examined the impact of obesity on fall risk. Self-reported falls, injurious falls, and health histories were obtained from 280,035 adults aged 45-79years in the 2014 Behavioral Risk Factor Surveillance System. Body mass index was categorized as underweight (<18.5kg/m 2 ), normal weight (18.5-24.9kg/m 2 ), overweight 25-29.9kg/m 2 ), class I obesity (30.0-34.9kg/m 2 ), or class II/III obesity (≥35.0kg/m 2 ) based on self-reported height and weight. Data were analyzed using weighted age- and sex-specific prevalence rates and Poisson regression. Overall, 11.0% reported ≥1 injurious fall in the previous 12months. Mid-life women 55-59years reported the highest prevalence of injurious falls (15.4%). Among mid-life women, overweight was associated with injurious falls (RR=1.17; 95% CI: 1.08, 1.28), but overweight was not associated with falling among other age-sex groups. Class II/III obesity was associated with injurious falls among all age-sex groups. After considering the mediators like health conditions (depression, cardiovascular disease, diabetes, arthritis) and behaviors (physical activity, sleep), the association of class II/III obesity and injurious fall risk persisted only among mid-life women (RR=1.23; 95% CI: 1.12, 1.36). Not only are mid-life women at high risk for falls, but the class II/III obesity is a risk factor for injurious falls. Targeting mid-life women for fall and injury prevention is an important aim for practitioners, particularly given unique correlates of falling for this group. Copyright © 2016 Elsevier Inc. All rights reserved.

Falls: Epidemiology, Pathophysiology, and Relationship to Fracture

PubMed Central

Berry, Sarah D.; Miller, Ram

2009-01-01

Falls are common in the elderly, and frequently result in injury, disability, and institutionalization. Although the causes of falls are complex, most falls result from an interaction between individual characteristics that increase an individual's propensity to fall and acute mediating risk factors that provide the opportunity to fall. Predisposing risk factors include age-associated changes in strength and balance, age-associated comorbidities such as osteoarthritis, visual impairment and dementia, psychotropic medications, and certain footwear. Fewer studies have focused on acute precipitating factors, but environmental and situational factors are clearly important to the risk of falls. Approximately 30% of falls result in an injury that requires medical attention and with fractures occurring in approximately 10% of falls. Fractures associated with falls are multi-factorial in origin. In addition to the traditional risk factors for falls, the fall descent, fall impact, and bone strength are all important determinants of whether a fracture will occur as a result of an event. In recent years, numerous studies have been directed toward the development of effective fall and fall-related fracture prevention interventions. PMID:19032925

Addressing the issue of falls off playground equipment: an empirically-based intervention to reduce fall-risk behaviors on playgrounds.

PubMed

Morrongiello, Barbara A; Matheis, Shawn

2007-08-01

The present study evaluated the impact of an intervention to reduce fall-risk behaviors on playgrounds among children 6-11 years of age. Children completed posters indicating risky playground behaviors they would and would not do. In the intervention group, video and audio presentations were used to expose children to injury occurrences so that injury vulnerability was communicated in a fear-evoking way. In the control group, children only completed the pre- and post-intervention measures. Significant decreases in intentions to risk-take were obtained in the intervention, but not the control group. Effectiveness did not vary with children's age or sex, but was greater for those scoring high in sensation-seeking. A fear-appeals approach proved successful to reduce intended fall-risk behaviors, particularly for children high in sensation-seeking whose risk-taking is motivated by affect arousal.

Constraining eye movement in individuals with Parkinson's disease during walking turns.

PubMed

Ambati, V N Pradeep; Saucedo, Fabricio; Murray, Nicholas G; Powell, Douglas W; Reed-Jones, Rebecca J

2016-10-01

Walking and turning is a movement that places individuals with Parkinson's disease (PD) at increased risk for fall-related injury. However, turning is an essential movement in activities of daily living, making up to 45 % of the total steps taken in a given day. Hypotheses regarding how turning is controlled suggest an essential role of anticipatory eye movements to provide feedforward information for body coordination. However, little research has investigated control of turning in individuals with PD with specific consideration for eye movements. The purpose of this study was to examine eye movement behavior and body segment coordination in individuals with PD during walking turns. Three experimental groups, a group of individuals with PD, a group of healthy young adults (YAC), and a group of healthy older adults (OAC), performed walking and turning tasks under two visual conditions: free gaze and fixed gaze. Whole-body motion capture and eye tracking characterized body segment coordination and eye movement behavior during walking trials. Statistical analysis revealed significant main effects of group (PD, YAC, and OAC) and visual condition (free and fixed gaze) on timing of segment rotation and horizontal eye movement. Within group comparisons, revealed timing of eye and head movement was significantly different between the free and fixed gaze conditions for YAC (p < 0.001) and OAC (p < 0.05), but not for the PD group (p > 0.05). In addition, while intersegment timings (reflecting segment coordination) were significantly different for YAC and OAC during free gaze (p < 0.05), they were not significantly different in PD. These results suggest individuals with PD do not make anticipatory eye and head movements ahead of turning and that this may result in altered segment coordination during turning. As such, eye movements may be an important addition to training programs for those with PD, possibly promoting better coordination during turning and potentially reducing the risk of falls.

Sensory interaction on static balance: a comparison concerning the history of falls of community-dwelling elderly.

PubMed

Ricci, Natalia Aquaroni; de Faria Figueiredo Gonçalves, Daniele; Coimbra, Arlete Maria Valente; Coimbra, Ibsen Bellini

2009-06-01

To determine whether elderly subjects with distinct histories of falls presented differences concerning the influence of sensory interaction on balance. Cross-sectional research. Ninety-six community-dwelling elderly subjects were divided into three groups, according to the history of falls within the past year (group 1, no falls; group 2, one fall; and group 3, recurrent falls). The Clinical Test of Sensory Interaction and Balance was used to evaluate the influence of sensory inputs on standing balance. The test required the subject to maintain stability during 30 s, under six conditions: (i) firm surface with eyes open; (ii) firm surface with eyes closed; (iii) firm surface with visual conflict; (iv) unstable surface with eyes open; (v) unstable surface with eyes closed; and (vi) unstable surface with visual conflict. The time expended on conditions and the number of abnormal cases were compared between groups. Each group was evaluated in relation to its performance in the progression of conditions. More abnormal cases occurred in group 3 compared to group 1 for conditions (iv) and (v); and compared to group 2 for condition (iv). Group 3 remained less time than group 1 under conditions (iv), (v) and (vi). Groups 1, 2 and 3 presented relevant decrements in trial duration from conditions (iv) to (v). For group 3, a significant decay was also noted from condition (i) to (ii). Sensorial interaction in the elderly varies according to their history of falls. Thus, it is possible to correctly guide the rehabilitation process and to prevent sensorial decays according to an individual's history of falls.

Learning to See the Infinite: Measuring Visual Literacy Skills in a 1st-Year Seminar Course

ERIC Educational Resources Information Center

Palmer, Michael S.; Matthews, Tatiana

2015-01-01

Visual literacy was a stated learning objective for the fall 2009 iteration of a first-year seminar course. To help students develop visual literacy skills, they received formal instruction throughout the semester and completed a series of carefully designed learning activities. The effects of these interventions were measured using a one-group…

Things Fall Apart and Come Together: Using the Visual for Reflection in Alternative Teacher Education Programmes

ERIC Educational Resources Information Center

Mitchell, Claudia; Dillon, David; Strong-Wilson, Teresa; Pithouse, Kathleen; Islam, Faisal; O'Connor, Kevin; Rudd, Christina; Staniforth, Patricia; Cole, Amy

2010-01-01

In this article, we focus on the use of the visual for reflection in "alternative" pre-service teacher education and, in particular, we address the question: "How and what can we learn about teacher education using the visual?" By way of illustration, we focus on the use of pre-service teachers' photographs in a public…

Oscillating Droplets and Incompressible Liquids: Slow-Motion Visualization of Experiments with Fluids

ERIC Educational Resources Information Center

Vollmer, Michael; Mollmann, Klaus-Peter

2012-01-01

We present fascinating simple demonstration experiments recorded with high-speed cameras in the field of fluid dynamics. Examples include oscillations of falling droplets, effects happening upon impact of a liquid droplet into a liquid, the disintegration of extremely large droplets in free fall and the consequences of incompressibility. (Contains…

Evaluation of fall armyworm resistance in maize germplasm lines using visual leaf injury rating and predator survey

USDA-ARS?s Scientific Manuscript database

After examining ear-colonizing pest resistance, 20 maize lines from the USDA-ARS germplasm enhancement of Maize (GEM) Program were evaluated for whorl-feeding fall armyworm (FAW) (Spodoptera frugiperda) resistance using four maize inbred lines as the resistant and susceptible controls. Both FAW inju...

Assessment of risk of falls in elderly living at home.

PubMed

Smith, Adriana de Azevedo; Silva, Antonia Oliveira; Rodrigues, Rosalina Aparecida Partezani; Moreira, Maria Adelaide Silva Paredes; Nogueira, Jordana de Almeida; Tura, Luiz Fernando Rangel

2017-04-06

to assess the risk of falls in elderly, by comparing the sociodemographic and cognitive factors, history of falls and self-reported comorbidities. cross-sectional and quantitative study with 240 elderly. Data were collected based on the social profile, through the instrument of risk of falls and assessment of falls, by univariate analysis, bivariate and multiple logistic regression. The Statistical Package for the Social Sciences (SPSS) version 19 was used for statistical analysis. there was a significant association of the risk of falls, as measured by the Fall Risk Score, with sex (<0.001), age (0.054), cognitive status (<0.001) and history of falls (<0.001). All variables were statistically significant and contributed to the occurrence of falls. In logistic regression, the variables that showed association with risk of falls were: fall, with whom they live, hypertension and visual impairment. female gender, older elderly (over 80 years old), with low cognitive status and occurrence of previous falls in the last six months are factors that increase the prevalence of falls. In logistic regression, the variables that were associated with risk of falls were: fall, with whom they live, visual impairment and rheumatologic diseases. avaliar o risco de quedas em idosos, comparando com os fatores sóciodemográficos, cognitivos, presença de quedas e co-morbidades autorreferidas. Estudo transversal e quantitativo com 240 idosos. Os dados foram coletados a partir do perfil social, instrumento do risco de quedas e avaliação de quedas, utilizando análise univariada, bivariada e regressão logística múltipla. Para a análise estatística, utilizou-se o Statistical Package for the Social Sciences (SPSS) versão 19. há associação entre o risco de quedas, mensurado pelo Fall Risk Score, com o sexo (<0,001), a faixa etária (0,054), o desempenho cognitivo (<0,001) e a presença de quedas (<0,001). Todas as variáveis apresentaram significância estatística e contribuíram para a ocorrência das quedas. Na regressão logística, as variáveis que apresentaram associação com o risco de quedas foram: queda, com quem mora, hipertensão arterial e déficit visual. sexo feminino, idoso mais velho (acima de 80 anos), com baixo desempenho cognitivo e apresentar quedas anteriores nos últimos seis meses, aumentam a prevalência de quedas. Na regressão logística, as variáveis que apresentaram associação com o risco de quedas foram: queda, com quem mora, visão prejudicada e doenças reumatológicas. evaluar el riesgo de caídas del adulto mayor, mediante la comparación de los factores cognitivos y sociodemográficos, antecedentes de caídas y comorbilidades auto-reportadas. estudio transversal y cuantitativo con 240 adultos mayores. Los datos fueron recolectados utilizando instrumento del riesgo de caídas y evaluación de caídas, mediante el análisis univariado, bivariado y regresión logística múltiple. Para el anpalisis estadístico, fue utilizado software Statistical Package for the Social Sciences (SPSS) versión 19, se utilizó en el análisis estadístico. hay una asociación significativa del riesgo de caídas, medido por el Fall Risk Score, con el sexo (<0.001), la edad (0.054), el desempeño cognitivo (<0.001) y los antecedentes de caídas (<0.001). Todas las variables fueron estadísticamente significativas y contribuyeron a la ocurrencia de caídas. En la regresión logística, las variables que mostraron asociación con el riesgo de caídas fueron: caída, con quien viven, hipertensión y discapacidad visual. sexo femenino, adulto mayor de edad más avanzada (más de 80 años de edad), bajo desempeño cognitivo, y antecedentes de caídas en los últimos seis meses son factores que aumentan la prevalencia de caídas. En la regresión logística, las variables que mostraron asociación con el riesgo de caídas fueron: caída, con quien vive, discapacidad visual y enfermedades reumáticas.

[Cataract surgery and its impact on balance and autonomy in elderly].

PubMed

Raynal, M; Aupy, B; Jahidi, A; Ettien, D; Le Page, P; Briche, T; Kossowski, M; Pailllaud, E

2009-01-01

Cataract is a major cause of visual impairment among elderly. Cataract surgery improves visual afferencies and can have an impact on balance. The present study assessed the impact of cataract surgery upon balance and autonomy in elderly. We realized clinical examinations and objective tests the day before surgery and 2-months later. The initial cohort consisted of 66 patients that had to undergo a cataract surgery. Their mean age was 79 +/- 0.5. For logistic reasons, only 33 patients have been completely evaluated before and after surgery. Each patient underwent a history and examination that have assessed autonomy, walking, visual and then cochleo-vestibular functions including bone vibratory test and dynamic computerized posturography (Equitest). After 2 months, cataract surgery had no incidence on balance. The fear of falling has stayed the same whereas the number of falls has been noticeably reduced by surgery. The overall score of Equitest has shown an increase in visual dependence after surgery. Although cataract surgery has no incidence on autonomy, it may improve the quality of life among older people by leisure activities recovery. An early physical rehabilitation facilitated by visual improvement after surgery can also prevent visual dependence and autonomy loss. We recommend vestibular rehabilitation in elderly with major visual dependence.

Risk of fall (RoF) intervention by affecting visual egocenter through gait analysis and yoked prisms.

PubMed

Padula, William V; Subramanian, Prem; Spurling, April; Jenness, Jonathan

2015-01-01

Following a neurologic event such as traumatic brain injury (TBI), cerebrovascular accident (CVA), and chronic neurological conditions including Parkinson's disease, multiple sclerosis, and cerebral palsy a shift in the visual midline (egocenter) can directly affect posture, balance and spatial orientation. As a consequence, this increases the risk of fall (RoF) and injury that imposes a major financial burden on the public health system. To determine if there is a statistically significant change in balance with the intervention of yoked prisms to reduce the risk of fall in subjects with neurological impairments. Ambulation of thirty-six subjects was evaluated on a pressure sensitive mat before and after intervention with yoked prisms. Changes in gait and balance were analyzed in the anterior-posterior (AP) and medial-lateral (ML) axes during ambulation. T-tests for each measure comparing the difference-of-differences to a zero change at baseline returned statistically significant reductions in both AP (p <  0.0001; 95% CI: 1.368- 2.976) and ML (p = 0.0002; 95% CI: 1.472- 4.173) imbalances using specifically directed yoked prisms to correct the visual midline deviation. These findings demonstrate that yoked prisms have the potential to provide a cost-effective means to restore the visual midline thereby improving balance, reduce RoF and subsequent injury.

Effects of lighting illuminance levels on stair negotiation performance in individuals with visual impairment.

PubMed

Shaheen, Aliah F; Sourlas, Alexandros; Horton, Khim; McLean, Christopher; Ewins, David; Gould, David; Ghoussayni, Salim

2018-04-01

Stair-related falls of older people cause a substantial financial and social burden. Deterioration of the visual system amongst other factors put older people at a high risk of falling. Improved lighting is often recommended. The aim of this study was to investigate the effect of lighting illuminance on stair negotiation performance in older individuals with visual impairment. Eleven participants aged 60 or over with a vision of 6/18 or worse ascended and descended a staircase under: 50 lx, 100 lx, 200 lx, 300 lx and distributed 200 lx lighting. A motion capture system was used to measure movements of the lower limb. Clearance, clearance variability, temporal and spatial parameters and joint/segment kinematics were computed. There was no effect on clearance or clearance variability. Participants had lower speed, cadence, increased cycle time and stance time in the 50 lx compared to 300 lx and distributed 200 lx lighting in descent. The minimum hip angle in ascent was increased in the 200 lx lighting. Clearance was found to be moderately correlated with balance scores. Individuals with visual impairment adopt precautionary gait in dim lighting conditions. This does not always result in improvements in the parameters associated with risk of falling (e.g. clearance). Copyright © 2018 Elsevier Ltd. All rights reserved.

Sensory organization for balance: specific deficits in Alzheimer's but not in Parkinson's disease.

PubMed

Chong, R K; Horak, F B; Frank, J; Kaye, J

1999-03-01

The cause of frequent falling in patients with dementia of the Alzheimer type (AD) is not well understood. Distraction from incongruent visual stimuli may be an important factor as suggested by their poor performance in tests of shifting visual attention in other studies. The purpose of this study was to determine whether AD patients have difficulty maintaining upright balance under absent and/or incongruent visual and other sensory conditions compared to nondemented healthy elderly persons and individuals with Parkinson's disease (PD). Seventeen healthy older adults, 15 medicated PD subjects, and 11 AD subjects underwent the Sensory Organization Test protocol. The incidence of loss of balance ("falls"), and the peak-to-peak amplitude of body center of mass sway during stance in the six sensory conditions were used to infer the ability to use visual, somatosensory, and vestibular signals when they provided useful information for balance, and to suppress them when they were incongruent as an orientation reference. Vestibular reflex tests were conducted to ensure normal vestibular function in the subjects. AD subjects had normal vestibular function but had trouble using it in condition 6, where they had to concurrently suppress both incongruent visual and somatosensory inputs. All 11 AD subjects fell in the first trial of this condition. With repeated trials, only three AD subjects were able to stay balanced. AD subjects were able to keep their balance when only somatosensory input was incongruent. In this condition, all AD subjects were able to maintain balance whereas some falls occurred in the other groups. In all conditions, when AD subjects did not fall, they were able to control as large a sway as the healthy controls, except when standing with eyes closed in condition 2: AD subjects did not increase their sway whereas the other groups did. In the PD group, the total fall incidence was similar to the AD group, but the distribution was generalized across more sensory conditions. PD subjects were also able to improve with repeated trials in condition 6. Patients with dementia of the Alzheimer type have decreased ability to suppress incongruent visual stimuli when trying to maintain balance. However, they did not seem to be dependent on vision for balance because they did not increase their sway when vision was absent. Parkinsonian patients have a more general balance control problem in the sensory organization test, possibly related to difficulty changing set.

A novel visual hardware behavioral language

NASA Technical Reports Server (NTRS)

Li, Xueqin; Cheng, H. D.

1992-01-01

Most hardware behavioral languages just use texts to describe the behavior of the desired hardware design. This is inconvenient for VLSI designers who enjoy using the schematic approach. The proposed visual hardware behavioral language has the ability to graphically express design information using visual parallel models (blocks), visual sequential models (processes) and visual data flow graphs (which consist of primitive operational icons, control icons, and Data and Synchro links). Thus, the proposed visual hardware behavioral language can not only specify hardware concurrent and sequential functionality, but can also visually expose parallelism, sequentiality, and disjointness (mutually exclusive operations) for the hardware designers. That would make the hardware designers capture the design ideas easily and explicitly using this visual hardware behavioral language.

Clinical history and biologic age predicted falls better than objective functional tests.

PubMed

Gerdhem, Paul; Ringsberg, Karin A M; Akesson, Kristina; Obrant, Karl J

2005-03-01

Fall risk assessment is important because the consequences, such as a fracture, may be devastating. The objective of this study was to find the test or tests that best predicted falls in a population-based sample of elderly women. The fall-predictive ability of a questionnaire, a subjective estimate of biologic age and objective functional tests (gait, balance [Romberg and sway test], thigh muscle strength, and visual acuity) were compared in 984 randomly selected women, all 75 years of age. A recalled fall was the most important predictor for future falls. Only recalled falls and intake of psycho-active drugs independently predicted future falls. Women with at least five of the most important fall predictors (previous falls, conditions affecting the balance, tendency to fall, intake of psychoactive medication, inability to stand on one leg, high biologic age) had an odds ratio of 11.27 (95% confidence interval 4.61-27.60) for a fall (sensitivity 70%, specificity 79%). The more time-consuming objective functional tests were of limited importance for fall prediction. A simple clinical history, the inability to stand on one leg, and a subjective estimate of biologic age were more important as part of the fall risk assessment.

Posturography and risk of recurrent falls in healthy non-institutionalized persons aged over 65.

PubMed

Buatois, Séverine; Gueguen, René; Gauchard, Gérome C; Benetos, Athanase; Perrin, Philippe P

2006-01-01

A poor postural stability in older people is associated with an increased risk of falling. The posturographic tool has widely been used to assess balance control; however, its value in predicting falls remains unclear. The purpose of this prospective study was to determine the predictive value of posturography in the estimation of the risk of recurrent falls, including a comparison with standard clinical balance tests, in healthy non-institutionalized persons aged over 65. Two hundred and six healthy non-institutionalized volunteers aged over 65 were tested. Postural control was evaluated by posturographic tests, performed on static, dynamic and dynamized platforms (static test, slow dynamic test and Sensory Organization Test [SOT]) and clinical balance tests (Timed 'Up & Go' test, One-Leg Balance, Sit-to-Stand-test). Subsequent falls were monitored prospectively with self-questionnaire sent every 4 months for a period of 16 months after the balance testing. Subjects were classified prospectively in three groups of Non-Fallers (0 fall), Single-Fallers (1 fall) and Multi-Fallers (more than 2 falls). Loss of balance during the last trial of the SOT sensory conflicting condition, when visual and somatosensory inputs were distorted, was the best factor to predict the risk of recurrent falls (OR = 3.6, 95% CI = 1.3-10.11). Multi-Fallers showed no postural adaptation during the repetitive trials of this sensory condition, contrary to Non-Fallers and Single-Fallers. The Multi-Fallers showed significantly more sway when visual inputs were occluded. The clinical balance tests, the static test and the slow dynamic test revealed no significant differences between the groups. In a sample of non-institutionalized older persons aged over 65, posturographic evaluation by the SOT, especially with repetition of the same task in sensory conflicting condition, compared to the clinical tests and the static and dynamic posturographic test, appears to be a more sensitive tool to identify those at high-risk of recurrent falls. Copyright (c) 2006 S. Karger AG, Basel.

A longitudinal cohort study of the impact of first- and both-eye cataract surgery on falls and other injuries in Vietnam

PubMed Central

To, Kien Gia; Meuleners, Lynn; Bulsara, Max; Fraser, Michelle L; Duong, Dat Van; Do, Dung Van; Huynh, Van-Anh Ngoc; Phi, Tien Duy; Tran, Hoang Huy; Nguyen, Nguyen Do

2014-01-01

Aim Little information exists on the impact of cataract surgery on falls and other injuries in Vietnam. The aim of this study was to determine the impact of first and both eye cataract surgery on the number of falls and other injuries among bilateral cataract patients in Ho Chi Minh City, Vietnam. Materials and methods A longitudinal cohort study was conducted involving 413 bilateral cataract patients aged 50+ years. Participants were assessed at three time points: 1 week before, 1–3 months after, and 1 year after first-eye cataract surgery. Visual measures (visual acuity, contrast sensitivity and stereopsis) were taken, and self-reported falls and injury data were collected. A multilevel longitudinal Poisson regression model was used to investigate change in the number of falls after surgery. Results The risk of falls decreased by 78% (incidence-rate ratio [IRR] 0.22, 95% confidence interval [CI] 0.06–0.77; P=0.018) in the year after cataract surgery for participants who had first-eye surgery only and 83% (IRR 0.17, 95% CI 0.04–0.69; P=0.012) for participants who had the second eye operated on compared to before surgery. The risk of falls was three times higher for females than males (IRR 3.13, 95% CI 1.53–6.40; P=0.002). Improved binocular contrast sensitivity was also associated with a decrease in falls (IRR 0.40, 95% CI 0.17–0.97; P=0.042). The prevalence of other injuries also decreased after cataract surgery. Conclusion Cataract surgery reduced the number of falls and other injuries in Vietnam. Contrast sensitivity may be important for ophthalmologists to consider when prioritizing patients for surgery and assessing their fall risk. PMID:24812501

Survey of visualization and analysis tools

NASA Technical Reports Server (NTRS)

Meyer, P. J.

1994-01-01

A large number of commercially available visualization and analysis tools are available to the researcher. Some of the strengths and limitations of some of these tools, from the viewpoint of the earth sciences discipline, are discussed. Visualization and analysis tools fall into one of two categories: those that are designed to a specific purpose and are non-extensive and those that are generic visual programming tools that are extensible. Most of the extensible packages examined incorporate a data flow paradigm.

Autoregressive-moving-average hidden Markov model for vision-based fall prediction-An application for walker robot.

PubMed

Taghvaei, Sajjad; Jahanandish, Mohammad Hasan; Kosuge, Kazuhiro

2017-01-01

Population aging of the societies requires providing the elderly with safe and dependable assistive technologies in daily life activities. Improving the fall detection algorithms can play a major role in achieving this goal. This article proposes a real-time fall prediction algorithm based on the acquired visual data of a user with walking assistive system from a depth sensor. In the lack of a coupled dynamic model of the human and the assistive walker a hybrid "system identification-machine learning" approach is used. An autoregressive-moving-average (ARMA) model is fitted on the time-series walking data to forecast the upcoming states, and a hidden Markov model (HMM) based classifier is built on the top of the ARMA model to predict falling in the upcoming time frames. The performance of the algorithm is evaluated through experiments with four subjects including an experienced physiotherapist while using a walker robot in five different falling scenarios; namely, fall forward, fall down, fall back, fall left, and fall right. The algorithm successfully predicts the fall with a rate of 84.72%.

Effects of a randomized controlled recurrent fall prevention program on risk factors for falls in frail elderly living at home in rural communities.

PubMed

Jeon, Mi Yang; Jeong, HyeonCheol; Petrofsky, Jerrold; Lee, Haneul; Yim, JongEun

2014-11-14

Falling can lead to severe health issues in the elderly and importantly contributes to morbidity, death, immobility, hospitalization, and early entry to long-term care facilities. The aim of this study was to devise a recurrent fall prevention program for elderly women in rural areas. This study adopted an assessor-blinded, randomized, controlled trial methodology. Subjects were enrolled in a 12-week recurrent fall prevention program, which comprised strength training, balance training, and patient education. Muscle strength and endurance of the ankles and the lower extremities, static balance, dynamic balance, depression, compliance with preventive behavior related to falls, fear of falling, and fall self-efficacy at baseline and immediately after the program were assessed. Sixty-two subjects (mean age 69.2±4.3 years old) completed the program--31 subjects in the experimental group and 31 subjects in the control group. When the results of the program in the 2 groups were compared, significant differences were found in ankle heel rise test, lower extremity heel rise test, dynamic balance, depression, compliance with fall preventative behavior, fear of falling, and fall self-efficacy (p<0.05), but no significant difference was found in static balance. This study shows that the fall prevention program described effectively improves muscle strength and endurance, balance, and psychological aspects in elderly women with a fall history.

The Neighborhood Environment: Perceived Fall Risk, Resources, and Strategies for Fall Prevention.

PubMed

Chippendale, Tracy; Boltz, Marie

2015-08-01

To explore the experience of older adults in their neighborhood in relation to perceived fall risk, fear of falling (FOF), and resources/strategies for fall prevention. Fourteen older adults, 65 years of age and older from 3 urban senior centers, participated in this qualitative study. The semistructured interview guidelines and background questionnaire were developed by the researchers based on the literature and an existing measure of walkability. Both tools were refined based on pilot interviews with seniors. Collaizzi's phenomenological method was used for data analysis. Five themes emerged from the data: (a) The built environment contributes to perceived fall risk and FOF, (b) personal strategies used to adapt to perceived neighborhood fall risks-behavioral approaches, (c) resources for physical activity and safety, (d) barriers to physical activity and exercise, and (e) neighborhood features as a motivator. Urban-dwelling seniors perceive that neighborhood features contribute to or mitigate fall risk and FOF. Behavioral strategies are used by seniors to prevent outdoor falls. The findings can help clinicians develop targeted fall prevention interventions for well elders and help urban planners to design and retrofit urban environments to reduce fall risk. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Free Falling in Stratified Fluids

NASA Astrophysics Data System (ADS)

Lam, Try; Vincent, Lionel; Kanso, Eva

2017-11-01

Leaves falling in air and discs falling in water are examples of unsteady descents due to complex interaction between gravitational and aerodynamic forces. Understanding these descent modes is relevant to many branches of engineering and science such as estimating the behavior of re-entry space vehicles to studying biomechanics of seed dispersion. For regularly shaped objects falling in homogenous fluids, the motion is relatively well understood. However, less is known about how density stratification of the fluid medium affects the falling behavior. Here, we experimentally investigate the descent of discs in both pure water and in stable linearly stratified fluids for Froude numbers Fr 1 and Reynolds numbers Re between 1000 -2000. We found that stable stratification (1) enhances the radial dispersion of the disc at landing, (2) increases the descent time, (3) decreases the inclination (or nutation) angle, and (4) decreases the fluttering amplitude while falling. We conclude by commenting on how the corresponding information can be used as a predictive model for objects free falling in stratified fluids.

A novel wearable smart button system for fall detection

NASA Astrophysics Data System (ADS)

Zhuang, Wei; Sun, Xiang; Zhi, Yueyan; Han, Yue; Mao, Hande

2017-05-01

Fall has been the second most cause of accidental injury to death in the world. It has been a serious threat to the physical and mental health of the elders. Therefore, developing wearable node system with fall detecting ability has become increasingly pressing at present. A novel smart button for long-term fall detection is proposed in this paper, which is able to accurately monitor the falling behavior, and sending warning message online as well. The smart button is based on the tri-axis acceleration sensor which is used to collect the body motion signals. By using the statistical metrics of acceleration characteristics, a new SVM classification algorithm with high positive accuracy and stability is proposed so as to classify the falls and activities of daily living, and the results can be real-time displayed on Android based mobile phone. The experiments show that our wearable node system can continuously monitor the falling behavior with positive rate 94.8%.

The development of a fear of falling interdisciplinary intervention program

PubMed Central

Gomez, Fernando; Curcio, Carmen-Lucia

2007-01-01

Objective: To describe the development process of a protocol for a fear of falling interdisciplinary intervention program based on the main factors associated with fear of falling. Design/methods: The process of developing a protocol consisted of defining the target population, selecting the initial assessment components, adapting the intervention program based on findings about fear of falling and restriction of activities in this population. Settings: University-affiliated outpatient vertigo, dizziness and falls clinic in coffee-growers zone of Colombian Andes Mountains. Results: An intervention program was developed based on three main falling conceptual models. A medical intervention, based on a biomedical and pathophysiological model, a physiotherapeutic intervention based on a postural control model and a psychological intervention based on a biological-behavioral model. Conclusion: This interdisciplinary fear of falling intervention program developed is based on particular characteristics of target population, with differences in the inclusion criteria and the program intervention components; with emphasis on medical (recurrent falls and dizziness evaluation and management), psychological (cognitive-behavioral therapy) and physiotherapeutic (balance and transfers training) components. PMID:18225468

Falls and Fractures: A systematic approach to screening and prevention.

PubMed

Ambrose, Anne Felicia; Cruz, Lisanne; Paul, Geet

2015-09-01

Falls are one of the major causes of mortality and morbidity in older adults. Every year, an estimated 30-40% of patients over the age of 65 will fall at least once. Falls lead to moderate to severe injuries, fear of falling, loss of independence and death in a third of those patients. Falls account for 87 % of all fractures in the elderly. These fractures are almost always due to low impact injuries in osteoporotic bones. Several organizations have recommended screening older patients to identify those with a high risk of falling and, or fractures. The present review provides a brief summary and update of the relevant literature, summarizing screening tools and interventions to prevent falls and fractures. The major risk factors identified are impaired balance and gait, polypharmacy, and history of previous falls. Other risk factors include advancing age, female gender, visual impairments, cognitive decline especially attention and executive dysfunction, and environmental factors. Recommendations for the clinician to screen and prevent falls in older patients are also summarized. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Simultaneous particle image velocimetry and chemiluminescence visualization of millisecond-pulsed current-voltage-induced perturbations of a premixed propane/air flame

NASA Astrophysics Data System (ADS)

Schmidt, Jacob; Kostka, Stanislav; Lynch, Amy; Ganguly, Biswa

2011-09-01

The effects of millisecond-wide, pulsed current-voltage-induced behavior in premixed laminar flames have been investigated through the simultaneous collection of particle image velocimetry (PIV) and chemiluminescence data with particular attention paid to the onset mechanisms. Disturbances caused by applied voltages of 2 kV over a 30-mm gap to a downward propagating, atmospheric pressure, premixed propane/air flame with a flow speed near 2 m/s and an equivalence ratio of 1.06 are investigated. The combined PIV and chemiluminescence-based experimental data show the observed disturbance originates only in or near the cathode fall region very close to the burner base. The data also suggest that the coupling mechanism responsible for the flame disturbance behavior is fluidic in nature, developing from the radial positive chemi-ion distribution and an ion-drift current-induced net body force that acts along the annular space discharge distribution in the reaction zone in or near the cathode fall. This net body force causes a reduction in flow speed above these near cathodic regions causing the base of the flame to laterally spread. Also, this effect seems to produce a velocity gradient leading to the transition of a laminar flame to turbulent combustion for higher applied current-voltage conditions as shown in previous work (Marcum and Ganguly in Combust Flame 143:27-36, 2005; Schmidt and Ganguly in 48th AIAA aerospace sciences meeting. Orlando, 2010).

The efficacy of treadmill training with and without projected visual context for improving walking ability and reducing fall incidence and fear of falling in older adults with fall-related hip fracture: a randomized controlled trial.

PubMed

van Ooijen, Mariëlle W; Roerdink, Melvyn; Trekop, Marga; Janssen, Thomas W J; Beek, Peter J

2016-12-28

The ability to adjust walking to environmental context is often reduced in older adults and, partly as result of this, falls are common in this population. A treadmill with visual context projected on its belt (e.g., obstacles and targets) allows for practicing step adjustments relative to that context, while concurrently exploiting the great amount of walking practice associated with conventional treadmill training. The present study was conducted to compare the efficacy of adaptability treadmill training, conventional treadmill training and usual physical therapy in improving walking ability and reducing fear of falling and fall incidence in older adults during rehabilitation from a fall-related hip fracture. In this parallel-group, open randomized controlled trial, seventy older adults with a recent fall-related hip fracture (83.3 ± 6.7 years, mean ± standard deviation) were recruited from inpatient rehabilitation care and block randomized to six weeks inpatient adaptability treadmill training (n = 24), conventional treadmill training (n = 23) or usual physical therapy (n = 23). Group allocation was only blind for assessors. Measures related to walking ability were assessed as the primary outcome before and after the intervention and at 4-week and 12-month follow-up. Secondary outcomes included general health, fear of falling, fall rate and proportion of fallers. Measures of general walking ability, general health and fear of falling improved significantly over time. Significant differences among the three intervention groups were only found for the Functional Ambulation Category and the dual-task effect on walking speed, which were in favor of respectively conventional treadmill training and adaptability treadmill training. Overall, adaptability treadmill training, conventional treadmill training and usual physical therapy resulted in similar effects on walking ability, fear of falling and fall incidence in older adults rehabilitating from a fall-related hip fracture. Additional post hoc subgroup analyses, with stratification for pre-fracture tolerated walking distance and executive function, revealed several intervention effects in favor of adaptability and conventional treadmill training, indicating superiority over usual physical therapy for certain subgroups. Future well-powered studies are necessary to univocally identify the characteristics of individuals who will benefit most from a particular intervention. The Netherlands Trial Register ( NTR3222 , 3 January 2012).

Changes in intrinsic local connectivity after reading intervention in children with autism.

PubMed

Maximo, Jose O; Murdaugh, Donna L; O'Kelley, Sarah; Kana, Rajesh K

2017-12-01

Most of the existing behavioral and cognitive intervention programs in autism spectrum disorders (ASD) have not been tested at the neurobiological level, thus falling short of finding quantifiable neurobiological changes underlying behavioral improvement. The current study takes a translational neuroimaging approach to test the impact of a structured visual imagery-based reading intervention on improving reading comprehension and assessing its underlying local neural circuitry. Behavioral and resting state functional MRI (rs-fMRI) data were collected from children with ASD who were randomly assigned to an Experimental group (ASD-EXP; n=14) and a Wait-list control group (ASD-WLC; n=14). Participants went through an established reading intervention training program (Visualizing and Verbalizing for language comprehension and thinking or V/V; 4-h per day, 10-weeks, 200h of face-to-face instruction). Local functional connectivity was examined using a connection density approach from graph theory focusing on brain areas considered part of the Reading Network. The main results are as follows: (I) the ASD-EXP group showed significant improvement, compared to the ASD-WLC group, in their reading comprehension ability evidenced from change in comprehension scores; (II) the ASD-EXP group showed increased local brain connectivity in Reading Network regions compared to the ASD-WLC group post-intervention; (III) intervention-related changes in local brain connectivity were observed in the ASD-EXP from pre to post-intervention; and (IV) improvement in language comprehension significantly predicted changes in local connectivity. The findings of this study provide novel insights into brain plasticity in children with developmental disorders using targeted intervention programs. Published by Elsevier Inc.

Social marketing to plan a fall prevention program for Latino construction workers.

PubMed

Menzel, Nancy N; Shrestha, Pramen P

2012-08-01

Latino construction workers experience disparities in occupational death and injury rates. The Occupational Safety and Health Administration funded a fall prevention training program at the University of Nevada, Las Vegas in response to sharp increases in fall-related accidents from 2005 to 2007. The grant's purpose was to improve fall protection for construction workers, with a focus on Latinos. This study assessed the effectiveness of social marketing for increasing fall prevention behaviors. A multi-disciplinary team used a social marketing approach to plan the program. We conducted same day class evaluations and follow-up interviews 8 weeks later. The classes met trainee needs as evidenced by class evaluations and increased safety behaviors. However, Spanish-speaking Latinos did not attend in the same proportion as their representation in the Las Vegas population. A social marketing approach to planning was helpful to customize the training to Latino worker needs. However, due to the limitations of behavior change strategies, future programs should target employers and their obligation to provide safer workplaces. Copyright © 2012 Wiley Periodicals, Inc.

Tailored Education for Older Patients to Facilitate Engagement in Falls Prevention Strategies after Hospital Discharge—A Pilot Randomized Controlled Trial

PubMed Central

Hill, Anne-Marie; Etherton-Beer, Christopher; Haines, Terry P.

2013-01-01

Background The aims of the study were to evaluate the effect of providing tailored falls prevention education in hospital on: i) engagement in targeted falls prevention behaviors in the month after discharge: ii) patients’ self-perceived risk and knowledge about falls and falls prevention strategies after receiving the education. Methods A pilot randomized controlled trial (n = 50): baseline and outcome assessments conducted by blinded researchers. Participants: hospital inpatients 60 years or older, discharged to the community. Participants were randomized into two groups. The intervention was a tailored education package consisting of multimedia falls prevention information with trained health professional follow-up, delivered in addition to usual care. Outcome measures were engagement in falls prevention behaviors in the month after discharge measured at one month after discharge with a structured survey, and participants’ knowledge, confidence and motivation levels before and after receiving the education. The feasibility of providing the intervention was examined and falls outcomes (falls, fall-related injuries) were also collected. Results Forty-eight patients (98%) provided follow-up data. The complete package was provided to 21 (84%) intervention group participants. Participants in the intervention group were significantly more likely to plan how to safely restart functional activities [Adjusted odds ratio 3.80, 95% CI (1.07, 13.52), p = 0.04] and more likely to complete other targeted behaviors such as completing their own home exercise program [Adjusted odds ratio 2.76, 95% CI (0.72, 10.50), p = 0.14] than the control group. The intervention group was significantly more knowledgeable, confident and motivated to engage in falls prevention strategies after receiving the education than the control group. There were 23 falls (n = 5 intervention; n = 18 control) and falls rates were 5.4/1000 patient days (intervention); 18.7/1000 patient days (control). Conclusion This tailored education was received positively by older people, resulted in increased engagement in falls prevention strategies after discharge and is feasible to deliver to older hospital patients. Trial registration The study was registered with the Australian New Zealand Clinical Trials Registry; ACTRN12611000963921 on 8th November 2011. PMID:23717424

Risk Factors for Falls and Fall-Related Injuries in Adults 85 Years of Age and Older

PubMed Central

Grundstrom, Anna C.; Guse, Clare E.; Layde, Peter M.

2011-01-01

Background Falls are a leading cause of morbidity and mortality in older adults. No previous studies on risk factors for falls have focused on adults 85 years and older, the most rapidly growing segment of adults. Methods We examined demographic, health, and behavioral risk factors for falls and fall-related injuries in adults 65 years and older, with a particular focus on adults 85 years and older. We analyzed self-reported information from the Behavioral Risk Factor Surveillance System (BRFSS) for 2008. Results Data was available for 120,923 people aged 65 or older and 12,684 people aged 85 or older. Of those aged 85 or older, 21.3% reported at least one fall in the past 3 months and 7.2% reported at least one fall related injury requiring medical care or limiting activity for a day or longer. Below average general health, male sex, perceived insufficient sleep, health problems requiring assistive devices, alcohol consumption, increasing body mass index and history of stroke were all independently associated with a greater risk of falls or fall related injuries. The greater risk of falling in those 85 years and older appeared to be due to the deterioration of overall health status with age; among those with excellent overall health status, there was no greater risk of falling in adults 85 years and older compared to those 65–84 years of age. Conclusions Our results suggest that those with risk factors for falls and fall-related injuries may be appropriate targets for evidence-based fall prevention programs. PMID:21862143

Risk factors for falls and fall-related injuries in adults 85 years of age and older.

PubMed

Grundstrom, Anna C; Guse, Clare E; Layde, Peter M

2012-01-01

Falls are a leading cause of morbidity and mortality in older adults. No previous studies on risk factors for falls have focused on adults 85 years and older, the most rapidly growing segment of adults. We examined demographic, health, and behavioral risk factors for falls and fall-related injuries in adults 65 years and older, with a particular focus on adults 85 years and older. We analyzed self-reported information from the Behavioral Risk Factor Surveillance System (BRFSS) for 2008. Data was available for 120,923 people aged 65 or older and 12,684 people aged 85 or older. Of those aged 85 or older, 21.3% reported at least one fall in the past 3 months and 7.2% reported at least one fall related injury requiring medical care or limiting activity for a day or longer. Below average general health, male sex, perceived insufficient sleep, health problems requiring assistive devices, alcohol consumption, increasing body mass index and history of stroke were all independently associated with a greater risk of falls or fall related injuries. The greater risk of falling in those 85 years and older appeared to be due to the deterioration of overall health status with age; among those with excellent overall health status, there was no greater risk of falling in adults 85 years and older compared to those 65-84 years of age. Our results suggest that those with risk factors for falls and fall-related injuries may be appropriate targets for evidence-based fall prevention programs. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Wandering in a dementia special care unit: behavioral aspects and the risk of falling.

PubMed

Merims, Doron; Nahari, Havazelet; Ben-Ari, Giora; Jamal, Samira; Vigder, Carola; Ben-Israel, Joshua

2013-07-01

Wandering is a common phenomenon among patients with dementia. While traditionally considered to be a behavioral problem, it also includes fundamental aspects of motor performance (e.g., gait and falls). To examine the difference in motor function and behavioral symptoms between patients with severe dementia who wander and those who do not. We conducted a retrospective study reviewing the medical records of 72 patients with severe dementia, all residents of a dementia special care unit. Motor and behavioral aspects were compared between "wanderers" and "non-wanderers." No difference was found in motor performance including the occurrence of falls between the wanderers and non-wanderers. A significant difference was found in aggressiveness and sleep disturbances, which were more frequent among the wanderers. There was no preference to wandering at a certain period of the day among the patients with sleep disturbances who wander. In a protected environment wandering is not a risk factor for falls. Sleep disturbances and wandering co-occur, but there is no circumstantial association between the two symptoms.

Effects of a Randomized Controlled Recurrent Fall Prevention Program on Risk Factors for Falls in Frail Elderly Living at Home in Rural Communities

PubMed Central

Jeon, Mi Yang; Jeong, HyeonCheol; Petrofsky, Jerrold; Lee, Haneul; Yim, JongEun

2014-01-01

Background Falling can lead to severe health issues in the elderly and importantly contributes to morbidity, death, immobility, hospitalization, and early entry to long-term care facilities. The aim of this study was to devise a recurrent fall prevention program for elderly women in rural areas. Material/Methods This study adopted an assessor-blinded, randomized, controlled trial methodology. Subjects were enrolled in a 12-week recurrent fall prevention program, which comprised strength training, balance training, and patient education. Muscle strength and endurance of the ankles and the lower extremities, static balance, dynamic balance, depression, compliance with preventive behavior related to falls, fear of falling, and fall self-efficacy at baseline and immediately after the program were assessed. Sixty-two subjects (mean age 69.2±4.3 years old) completed the program – 31 subjects in the experimental group and 31 subjects in the control group. Results When the results of the program in the 2 groups were compared, significant differences were found in ankle heel rise test, lower extremity heel rise test, dynamic balance, depression, compliance with fall preventative behavior, fear of falling, and fall self-efficacy (p<0.05), but no significant difference was found in static balance. Conclusions This study shows that the fall prevention program described effectively improves muscle strength and endurance, balance, and psychological aspects in elderly women with a fall history. PMID:25394805

Effectiveness of a combination of cognitive behavioral therapy and task-oriented balance training in reducing the fear of falling in patients with chronic stroke: study protocol for a randomized controlled trial.

PubMed

Liu, Tai-Wa; Ng, Gabriel Y F; Ng, Shamay S M

2018-03-07

The consequences of falls are devastating for patients with stroke. Balance problems and fear of falling are two major challenges, and recent systematic reviews have revealed that habitual physical exercise training alone cannot reduce the occurrence of falls in stroke survivors. However, recent trials with community-dwelling healthy older adults yielded the promising result that interventions with a cognitive behavioral therapy (CBT) component can simultaneously promote balance and reduce the fear of falling. Therefore, the aim of the proposed clinical trial is to evaluate the effectiveness of a combination of CBT and task-oriented balance training (TOBT) in promoting subjective balance confidence, and thereby reducing fear-avoidance behavior, improving balance ability, reducing fall risk, and promoting independent living, community reintegration, and health-related quality of life of patients with stroke. The study will constitute a placebo-controlled single-blind parallel-group randomized controlled trial in which patients are assessed immediately, at 3 months, and at 12 months. The selected participants will be randomly allocated into one of two parallel groups (the experimental group and the control group) with a 1:1 ratio. Both groups will receive 45 min of TOBT twice per week for 8 weeks. In addition, the experimental group will receive a 45-min CBT-based group intervention, and the control group will receive 45 min of general health education (GHE) twice per week for 8 weeks. The primary outcome measure is subjective balance confidence. The secondary outcome measures are fear-avoidance behavior, balance ability, fall risk, level of activities of daily living, community reintegration, and health-related quality of life. The proposed clinical trial will compare the effectiveness of CBT combined with TOBT and GHE combined with TOBT in promoting subjective balance confidence among chronic stroke patients. We hope our results will provide evidence of a safe, cost-effective, and readily transferrable therapeutic approach to clinical practice that reduces fear-avoidance behavior, improves balance ability, reduces fall risk, promotes independence and community reintegration, and enhances health-related quality of life. ClinicalTrials.gov, NCT02937532 . Registered on 17 October 2016.

Free-fall dynamics of a pair of rigidly linked disks

NASA Astrophysics Data System (ADS)

Kim, Taehyun; Chang, Jaehyeock; Kim, Daegyoum

2018-03-01

We investigate experimentally the free-fall motion of a pair of identical disks rigidly connected to each other. The three-dimensional coordinates of the pair of falling disks were constructed to quantitatively describe its trajectory, and the flow structure formed by the disk pair was identified by using dye visualization. The rigidly linked disk pair exhibits a novel falling pattern that creates a helical path with a conical configuration in which the lower disk rotates in a wider radius than the upper disk with respect to a vertical axis. The helical motion occurs consistently for the range of disk separation examined in this study. The dye visualization reveals that a strong, noticeable helical vortex core is generated from the outer tip of the lower disk during the helical motion. With an increasing length ratio, which is the ratio of the disk separation to the diameter of the disks, the nutation angle and the rate of change in the precession angle that characterize the combined helical and conical kinematics decrease linearly, whereas the pitch of the helical path increases linearly. Although all disk pairs undergo this helical motion, the horizontal-drift patterns of the disk pair depend on the length ratio.

Classroom Peer Relationships and Behavioral Engagement in Elementary School: The Role of Social Network Equity

PubMed Central

Cappella, Elise; Kim, Ha Yeon; Neal, Jennifer W.; Jackson, Daisy R.

2014-01-01

Applying social capital and systems theories of social processes, we examine the role of the classroom peer context in the behavioral engagement of low-income students (N = 80) in urban elementary school classrooms (N = 22). Systematic child observations were conducted to assess behavioral engagement among second to fifth graders in the fall and spring of the same school year. Classroom observations, teacher and child questionnaires, and social network data were collected in the fall. Confirming prior research, results from multilevel models indicate that students with more behavioral difficulties or less academic motivation in the fall were less behaviorally engaged in the spring. Extending prior research, classrooms with more equitably distributed and interconnected social ties—social network equity—had more behaviorally engaged students in the spring, especially in classrooms with higher levels of observed organization (i.e., effective management of behavior, time, and attention). Moreover, social network equity attenuated the negative relation between student behavioral difficulties and behavioral engagement, suggesting that students with behavioral difficulties were less disengaged in classrooms with more equitably distributed and interconnected social ties. Findings illuminate the need to consider classroom peer contexts in future research and intervention focused on the behavioral engagement of students in urban elementary schools. PMID:24081319

When Darkness Falls: A Journey into Visual Disability

ERIC Educational Resources Information Center

Jay, Karla

2006-01-01

Choroidal neovascularization is a rare condition where aberrant blood vessels behind the retina grow and then bleed, eventually becoming blind areas called Fuchs' spots. A woman suffering from this rare eye disease speaks about the challenges of coping with the visual disability and her determination to make the best of what life has to offer.

Avoidance of Heights on the Visual Cliff in Newly Walking Infants

ERIC Educational Resources Information Center

Witherington, David C.; Campos, Joseph J.; Anderson, David I.; Lejeune, Laure; Seah, Eileen

2005-01-01

Work with infants on the "visual cliff" links avoidance of drop-offs to experience with self-produced locomotion. Adolph's (2002) research on infants' perception of slope and gap traversability suggests that learning to avoid falling down is highly specific to the postural context in which it occurs. Infants, for example, who have…

The Changing Role of the Educational Video in Higher Distance Education

ERIC Educational Resources Information Center

Laaser, Wolfram; Toloza, Eduardo A.

2017-01-01

The article argues that the ongoing usage of audio visual media is falling behind in terms of educational quality compared to prior achievements in the history of distance education. After reviewing some important steps and experiences of audio visual digital media development, we analyse predominant presentation formats on the Web. Special focus…

Short-Term Memory for Space and Time Flexibly Recruit Complementary Sensory-Biased Frontal Lobe Attention Networks.

PubMed

Michalka, Samantha W; Kong, Lingqiang; Rosen, Maya L; Shinn-Cunningham, Barbara G; Somers, David C

2015-08-19

The frontal lobes control wide-ranging cognitive functions; however, functional subdivisions of human frontal cortex are only coarsely mapped. Here, functional magnetic resonance imaging reveals two distinct visual-biased attention regions in lateral frontal cortex, superior precentral sulcus (sPCS) and inferior precentral sulcus (iPCS), anatomically interdigitated with two auditory-biased attention regions, transverse gyrus intersecting precentral sulcus (tgPCS) and caudal inferior frontal sulcus (cIFS). Intrinsic functional connectivity analysis demonstrates that sPCS and iPCS fall within a broad visual-attention network, while tgPCS and cIFS fall within a broad auditory-attention network. Interestingly, we observe that spatial and temporal short-term memory (STM), respectively, recruit visual and auditory attention networks in the frontal lobe, independent of sensory modality. These findings not only demonstrate that both sensory modality and information domain influence frontal lobe functional organization, they also demonstrate that spatial processing co-localizes with visual processing and that temporal processing co-localizes with auditory processing in lateral frontal cortex. Copyright © 2015 Elsevier Inc. All rights reserved.

Fall risk and incidence reduction in high risk individuals with multiple sclerosis: a pilot randomized control trial.

PubMed

Sosnoff, Jacob J; Moon, Yaejin; Wajda, Douglas A; Finlayson, Marcia L; McAuley, Edward; Peterson, Elizabeth W; Morrison, Steve; Motl, Robert W

2015-10-01

To determine the feasibility of three fall prevention programs delivered over 12 weeks among individuals with multiple sclerosis: (A) a home-based exercise program targeting physiological risk factors; (B) an educational program targeting behavioral risk factors; and (C) a combined exercise-and-education program targeting both factors. Randomized controlled trial. Home-based training with assessments at research laboratory. A total of 103 individuals inquired about the investigation. After screening, 37 individuals with multiple sclerosis who had fallen in the last year and ranged in age from 45-75 years volunteered for the investigation. A total of 34 participants completed postassessment following the 12-week intervention. Participants were randomly assigned into one of four conditions: (1) wait-list control (n = 9); (2) home-based exercise (n = 11); (3) education (n = 9); or (4) a combined exercise and education (n = 8) group. Before and after the 12-week interventions, participants underwent a fall risk assessment as determined by the physiological profile assessment and provided information on their fall prevention behaviors as indexed by the Falls Prevention Strategy Survey. Participants completed falls diaries during the three-months postintervention. A total of 34 participants completed postintervention testing. Procedures and processes were found to be feasible. Overall, fall risk scores were lower in the exercise groups (1.15 SD 1.31) compared with the non-exercise groups (2.04 SD 1.04) following the intervention (p < 0.01). There was no group difference in fall prevention behaviors (p > 0.05). Further examination of home-based exercise/education programs for reducing falls in individuals with multiple sclerosis is warranted. A total of 108 participants would be needed in a larger randomized controlled trial.ClinicalTrials.org #NCT01956227. © The Author(s) 2014.

To crash or not to crash: how do hoverflies cope with free-fall situations and weightlessness?

PubMed

Goulard, Roman; Vercher, Jean-Louis; Viollet, Stéphane

2016-08-15

Insects' aptitude to perform hovering, automatic landing and tracking tasks involves accurately controlling their head and body roll and pitch movements, but how this attitude control depends on an internal estimation of gravity orientation is still an open question. Gravity perception in flying insects has mainly been studied in terms of grounded animals' tactile orientation responses, but it has not yet been established whether hoverflies use gravity perception cues to detect a nearly weightless state at an early stage. Ground-based microgravity simulators provide biologists with useful tools for studying the effects of changes in gravity. However, in view of the cost and the complexity of these set-ups, an alternative Earth-based free-fall procedure was developed with which flying insects can be briefly exposed to microgravity under various visual conditions. Hoverflies frequently initiated wingbeats in response to an imposed free fall in all the conditions tested, but managed to avoid crashing only in variably structured visual environments, and only episodically in darkness. Our results reveal that the crash-avoidance performance of these insects in various visual environments suggests the existence of a multisensory control system based mainly on vision rather than gravity perception. © 2016. Published by The Company of Biologists Ltd.

Assessing gait adaptability in people with a unilateral amputation on an instrumented treadmill with a projected visual context.

PubMed

Houdijk, Han; van Ooijen, Mariëlle W; Kraal, Jos J; Wiggerts, Henri O; Polomski, Wojtek; Janssen, Thomas W J; Roerdink, Melvyn

2012-11-01

Gait adaptability, including the ability to avoid obstacles and to take visually guided steps, is essential for safe movement through a cluttered world. This aspect of walking ability is important for regaining independent mobility but is difficult to assess in clinical practice. The objective of this study was to investigate the validity of an instrumented treadmill with obstacles and stepping targets projected on the belt's surface for assessing prosthetic gait adaptability. This was an observational study. A control group of people who were able bodied (n=12) and groups of people with transtibial (n=12) and transfemoral (n=12) amputations participated. Participants walked at a self-selected speed on an instrumented treadmill with projected visual obstacles and stepping targets. Gait adaptability was evaluated in terms of anticipatory and reactive obstacle avoidance performance (for obstacles presented 4 steps and 1 step ahead, respectively) and accuracy of stepping on regular and irregular patterns of stepping targets. In addition, several clinical tests were administered, including timed walking tests and reports of incidence of falls and fear of falling. Obstacle avoidance performance and stepping accuracy were significantly lower in the groups with amputations than in the control group. Anticipatory obstacle avoidance performance was moderately correlated with timed walking test scores. Reactive obstacle avoidance performance and stepping accuracy performance were not related to timed walking tests. Gait adaptability scores did not differ in groups stratified by incidence of falls or fear of falling. Because gait adaptability was affected by walking speed, differences in self-selected walking speed may have diminished differences in gait adaptability between groups. Gait adaptability can be validly assessed by use of an instrumented treadmill with a projected visual context. When walking speed is taken into account, this assessment provides unique, quantitative information about walking ability in people with a lower-limb amputation.

A vision-based fall detection algorithm of human in indoor environment

NASA Astrophysics Data System (ADS)

Liu, Hao; Guo, Yongcai

2017-02-01

Elderly care becomes more and more prominent in China as the population is aging fast and the number of aging population is large. Falls, as one of the biggest challenges in elderly guardianship system, have a serious impact on both physical health and mental health of the aged. Based on feature descriptors, such as aspect ratio of human silhouette, velocity of mass center, moving distance of head and angle of the ultimate posture, a novel vision-based fall detection method was proposed in this paper. A fast median method of background modeling with three frames was also suggested. Compared with the conventional bounding box and ellipse method, the novel fall detection technique is not only applicable for recognizing the fall behaviors end of lying down but also suitable for detecting the fall behaviors end of kneeling down and sitting down. In addition, numerous experiment results showed that the method had a good performance in recognition accuracy on the premise of not adding the cost of time.

Home Safety, Safe Behaviors of Elderly People, and Fall Accidents At Home

ERIC Educational Resources Information Center

Erkal, Sibel

2010-01-01

The present study analyzed home safety and safe behaviors against fall accidents of elderly people living at home. The study group comprised 121 people aged 65+ living in the catchment area of Ankara Mamak Halil Ulgen Health Center. Data were collected via a personal information form and Home-Screen Scale. Statistical analysis used an independent…

Quantifying Fall-Related Hazards in the Homes of Persons with Glaucoma.

PubMed

Yonge, Andrea V; Swenor, Bonnielin K; Miller, Rhonda; Goldhammer, Victoria; West, Sheila K; Friedman, David S; Gitlin, Laura N; Ramulu, Pradeep Y

2017-04-01

To characterize fall-related hazards in the homes of persons with suspected or diagnosed glaucoma, and to determine whether those with worse visual field (VF) damage have fewer home hazards. Cross-sectional study using baseline (2013-2015) data from the ongoing Falls in Glaucoma Study (FIGS). One-hundred seventy-four of 245 (71.0%) FIGS participants agreeing to the home assessment. Participants' homes were assessed using the Home Environment Assessment for the Visually Impaired (HEAVI). A single evaluator assessed up to 127 potential hazards in 8 home regions. In the clinic, binocular contrast sensitivity (CS) and better-eye visual acuity (VA) were evaluated, and 24-2 VFs were obtained to calculate average integrated VF (IVF) sensitivity. Total number of home hazards. No significant visual or demographic differences were noted between participants who did and did not complete the home assessment (P > 0.09 for all measures). Mean age among those completing the home assessment (n = 174) was 71.1 years, and IVF sensitivity ranged from 5.6 to 33.4 dB (mean = 27.2 dB, standard deviation [SD] = 4.0 dB). The mean number of items graded per home was 85.2 (SD = 13.2), and an average of 32.7 (38.3%) were identified as hazards. IVF sensitivity, CS, and VA were not associated with total home hazards or the number of hazards in any given room (P > 0.06 for all visual measures and rooms). The bathroom contained the greatest number of hazards (mean = 7.9; 54.2% of graded items classified as hazardous), and the most common hazards identified in at least 1 room were ambient lighting <300 lux and exposed light bulbs. Only 27.9% of graded rooms had adequate lighting. IVF sensitivity, CS, and VA were not associated with home lighting levels (P > 0.18 for all), but brighter room lighting was noted in the homes of participants with higher median income (P < 0.001). Multiple home fall hazards were identified in the study population, and hazard numbers were not lower for persons with worse VF damage, suggesting that individuals with more advanced glaucoma do not adapt their homes for safety. Further work should investigate whether addressing home hazards is an effective intervention for preventing falls in this high-risk group. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Martial arts fall training to prevent hip fractures in the elderly.

PubMed

Groen, B E; Smulders, E; de Kam, D; Duysens, J; Weerdesteyn, V

2010-02-01

Hip fractures are a common and serious consequence of falls. Training of proper fall techniques may be useful to prevent hip fractures in the elderly. The results suggested that martial arts fall techniques may be trainable in older individuals. Better performance resulted in a reduced impact force. Hip fractures are a common and serious consequence of falls. Fall training may be useful to prevent hip fractures in the elderly. This pilot study determined whether older individuals could learn martial arts (MA) fall techniques and whether this resulted in a reduced hip impact force during a sideways fall. Six male and nineteen female healthy older individuals completed a five-session MA fall training. Before and after training, force and kinematic data were collected during volitional sideways falls from kneeling position. Two MA experts evaluated the fall performance. Fear of falling was measured with a visual analog scale (VAS). After fall training, fall performance from a kneeling position was improved by a mean increase of 1.6 on a ten-point scale (P < 0.001). Hip impact force was reduced by a mean of 8% (0.20 N/N, P = 0.016). Fear of falling was reduced by 0.88 on a VAS scale (P = 0.005). MA techniques may be trainable in older individuals, and a better performance may reduce the hip impact force in a volitional sideways fall from a kneeling position. The additional reduction of fear of falling might result in the prevention of falls and related injuries.

Defining behavioral and molecular differences between summer and migratory monarch butterflies

PubMed Central

Zhu, Haisun; Gegear, Robert J; Casselman, Amy; Kanginakudru, Sriramana; Reppert, Steven M

2009-01-01

Background In the fall, Eastern North American monarch butterflies (Danaus plexippus) undergo a magnificent long-range migration. In contrast to spring and summer butterflies, fall migrants are juvenile hormone deficient, which leads to reproductive arrest and increased longevity. Migrants also use a time-compensated sun compass to help them navigate in the south/southwesterly direction en route for Mexico. Central issues in this area are defining the relationship between juvenile hormone status and oriented flight, critical features that differentiate summer monarchs from fall migrants, and identifying molecular correlates of behavioral state. Results Here we show that increasing juvenile hormone activity to induce summer-like reproductive development in fall migrants does not alter directional flight behavior or its time-compensated orientation, as monitored in a flight simulator. Reproductive summer butterflies, in contrast, uniformly fail to exhibit directional, oriented flight. To define molecular correlates of behavioral state, we used microarray analysis of 9417 unique cDNA sequences. Gene expression profiles reveal a suite of 40 genes whose differential expression in brain correlates with oriented flight behavior in individual migrants, independent of juvenile hormone activity, thereby molecularly separating fall migrants from summer butterflies. Intriguing genes that are differentially regulated include the clock gene vrille and the locomotion-relevant tyramine beta hydroxylase gene. In addition, several differentially regulated genes (37.5% of total) are not annotated. We also identified 23 juvenile hormone-dependent genes in brain, which separate reproductive from non-reproductive monarchs; genes involved in longevity, fatty acid metabolism, and innate immunity are upregulated in non-reproductive (juvenile-hormone deficient) migrants. Conclusion The results link key behavioral traits with gene expression profiles in brain that differentiate migratory from summer butterflies and thus show that seasonal changes in genomic function help define the migratory state. PMID:19335876

Root starch in defoliated sugar maples following thrips damage

Treesearch

Barbara S. Burns

1991-01-01

Sugar maple root starch evaluations were done in 1987 and 1988 as a service to Vermont sugarmakers concerned about tree health. Trees were rated for starch content in late fall, using a visual iodine-staining technique. On the average, trees with heavy pear thrips damage in the spring of 1988 had higher levels of root starch the following fall than trees with light or...

Selective attentional processing to fall-relevant stimuli among older adults who fear falling.

PubMed

Brown, Lesley A; White, Patti; Doan, Jonathan B; de Bruin, Natalie

2011-05-01

Fear of falling is known to affect more than half of community-dwelling older adults over 60 years of age. This fear is associated with physical and psychological effects that increase the risk of falling. The authors' theory is that attentional processing biases may exist in this population that serve to perpetuate fear of falling and subsequently increase fall risk. As a starting point in testing this proposition, the authors examined selective attentional processing bias to fall-relevant stimuli among older adults. Thirty older adult participants (M(age) = 70.8 ± 5.8), self-categorized to be Fearful of Falling (FF, n = 15) or Non-Fearful of Falling (NF, n = 15) completed a visual dot-probe paradigm to determine detection latencies to fall-threatening and general-threat stimuli. Attentional processing was defined using three index scores: attentional bias, congruency index, and incongruency index. Bias indicates capture of attention, whereas congruency and incongruency imply vigilance and disengagement difficulty, respectively. Both groups showed an attentional bias to fall-threat words but those who were fearful of falling also showed an incongruency effect for fall-threat words. These findings confirm that selective attentional processing profiles for fall-relevant stimuli differ between older adults who exhibit fear of falling and those who do not have this fear. Moreover, in accordance with current interpretations of selective attentional processing, the incongruency effect noted among fall-fearful older adults presents a possibility for a difficulty disengaging from fall-threatening stimuli.

Fragile X Mental Retardation Protein Is Required to Maintain Visual Conditioning-Induced Behavioral Plasticity by Limiting Local Protein Synthesis

PubMed Central

Liu, Han-Hsuan

2016-01-01

Fragile X mental retardation protein (FMRP) is thought to regulate neuronal plasticity by limiting dendritic protein synthesis, but direct demonstration of a requirement for FMRP control of local protein synthesis during behavioral plasticity is lacking. Here we tested whether FMRP knockdown in Xenopus optic tectum affects local protein synthesis in vivo and whether FMRP knockdown affects protein synthesis-dependent visual avoidance behavioral plasticity. We tagged newly synthesized proteins by incorporation of the noncanonical amino acid azidohomoalanine and visualized them with fluorescent noncanonical amino acid tagging (FUNCAT). Visual conditioning and FMRP knockdown produce similar increases in FUNCAT in tectal neuropil. Induction of visual conditioning-dependent behavioral plasticity occurs normally in FMRP knockdown animals, but plasticity degrades over 24 h. These results indicate that FMRP affects visual conditioning-induced local protein synthesis and is required to maintain the visual conditioning-induced behavioral plasticity. SIGNIFICANCE STATEMENT Fragile X syndrome (FXS) is the most common form of inherited intellectual disability. Exaggerated dendritic protein synthesis resulting from loss of fragile X mental retardation protein (FMRP) is thought to underlie cognitive deficits in FXS, but no direct evidence has demonstrated that FMRP-regulated dendritic protein synthesis affects behavioral plasticity in intact animals. Xenopus tadpoles exhibit a visual avoidance behavior that improves with visual conditioning in a protein synthesis-dependent manner. We showed that FMRP knockdown and visual conditioning dramatically increase protein synthesis in neuronal processes. Furthermore, induction of visual conditioning-dependent behavioral plasticity occurs normally after FMRP knockdown, but performance rapidly deteriorated in the absence of FMRP. These studies show that FMRP negatively regulates local protein synthesis and is required to maintain visual conditioning-induced behavioral plasticity in vivo. PMID:27383604

Fragile X Mental Retardation Protein Is Required to Maintain Visual Conditioning-Induced Behavioral Plasticity by Limiting Local Protein Synthesis.

PubMed

Liu, Han-Hsuan; Cline, Hollis T

2016-07-06

Fragile X mental retardation protein (FMRP) is thought to regulate neuronal plasticity by limiting dendritic protein synthesis, but direct demonstration of a requirement for FMRP control of local protein synthesis during behavioral plasticity is lacking. Here we tested whether FMRP knockdown in Xenopus optic tectum affects local protein synthesis in vivo and whether FMRP knockdown affects protein synthesis-dependent visual avoidance behavioral plasticity. We tagged newly synthesized proteins by incorporation of the noncanonical amino acid azidohomoalanine and visualized them with fluorescent noncanonical amino acid tagging (FUNCAT). Visual conditioning and FMRP knockdown produce similar increases in FUNCAT in tectal neuropil. Induction of visual conditioning-dependent behavioral plasticity occurs normally in FMRP knockdown animals, but plasticity degrades over 24 h. These results indicate that FMRP affects visual conditioning-induced local protein synthesis and is required to maintain the visual conditioning-induced behavioral plasticity. Fragile X syndrome (FXS) is the most common form of inherited intellectual disability. Exaggerated dendritic protein synthesis resulting from loss of fragile X mental retardation protein (FMRP) is thought to underlie cognitive deficits in FXS, but no direct evidence has demonstrated that FMRP-regulated dendritic protein synthesis affects behavioral plasticity in intact animals. Xenopus tadpoles exhibit a visual avoidance behavior that improves with visual conditioning in a protein synthesis-dependent manner. We showed that FMRP knockdown and visual conditioning dramatically increase protein synthesis in neuronal processes. Furthermore, induction of visual conditioning-dependent behavioral plasticity occurs normally after FMRP knockdown, but performance rapidly deteriorated in the absence of FMRP. These studies show that FMRP negatively regulates local protein synthesis and is required to maintain visual conditioning-induced behavioral plasticity in vivo. Copyright © 2016 the authors 0270-6474/16/367325-15$15.00/0.

Effect of Selected Balance Exercises on the Dynamic Balance of Children with Visual Impairments

ERIC Educational Resources Information Center

Jazi, Shirin Davarpanah; Purrajabi, Fatemeh; Movahedi, Ahmadreza; Jalali, Shahin

2012-01-01

Introduction: Maintaining balance while walking is of utmost importance for individuals with visual impairments because deficits in dynamic balance have been associated with a high risk of falling. Thus, the primary aim of the study presented here was to determine whether balance training effects the dynamic balance of children with visual…

Imagery and Fear Influence Height Perception

PubMed Central

Clerkin, Elise M.; Cody, Meghan W.; Stefanucci, Jeanine K.; Proffitt, Dennis R.; Teachman, Bethany A.

2008-01-01

The current study tested whether height overestimation is related to height fear and influenced by images of falling. To assess perceptual biases, participants high (n = 65) versus low (n = 64) in height fear estimated the vertical extents of two balconies using a visual matching task. On one of the balconies, participants engaged in an imagery exercise designed to enhance the subjective sense that they were acting in a dangerous environment by picturing themselves falling. As expected, we found that individuals overestimated the balcony’s height more after they imagined themselves falling, particularly if they were already afraid of heights. These findings suggest that height fear may serve as a vulnerability factor that leads to perceptual biases when triggered by a stressor (in this case, images of falling). PMID:19162437

Imagery and fear influence height perception.

PubMed

Clerkin, Elise M; Cody, Meghan W; Stefanucci, Jeanine K; Proffitt, Dennis R; Teachman, Bethany A

2009-04-01

The current study tested whether height overestimation is related to height fear and influenced by images of falling. To assess perceptual biases, participants high (n=65) versus low (n=64) in height fear estimated the vertical extents of two balconies using a visual matching task. On one of the balconies, participants engaged in an imagery exercise designed to enhance the subjective sense that they were acting in a dangerous environment by picturing themselves falling. As expected, we found that individuals overestimated the balcony's height more after they imagined themselves falling, particularly if they were already afraid of heights. These findings suggest that height fear may serve as a vulnerability factor that leads to perceptual biases when triggered by a stressor (in this case, images of falling).

Clinical and Community Strategies to Prevent Falls and Fall-Related Injuries Among Community-Dwelling Older Adults.

PubMed

Taylor-Piliae, Ruth E; Peterson, Rachel; Mohler, Martha Jane

2017-09-01

Falls in older adults are the result of several risk factors across biological and behavioral aspects of the person, along with environmental factors. Falls can trigger a downward spiral in activities of daily living, independence, and overall health outcomes. Clinicians who care for older adults should screen them annually for falls. A multifactorial comprehensive clinical fall assessment coupled with tailored interventions can result in a dramatic public health impact, while improving older adult quality of life. For community-dwelling older adults, effective fall prevention has the potential to reduce serious fall-related injuries, emergency room visits, hospitalizations, institutionalization, and functional decline. Copyright © 2017 Elsevier Inc. All rights reserved.

A Three Pronged Approach for Improved Data Understanding: 3-D Visualization, Use of Gaming Techniques, and Intelligent Advisory Agents

DTIC Science & Technology

2006-10-01

Pronged Approach for Improved Data Understanding: 3-D Visualization, Use of Gaming Techniques, and Intelligent Advisory Agents. In Visualising Network...University at the start of each fall semester, when numerous new students arrive on campus and begin downloading extensive amounts of audio and...SIGGRAPH ’92 • C. Cruz-Neira, D.J. Sandin, T.A. DeFanti, R.V. Kenyon and J.C. Hart, "The CAVE: Audio Visual Experience Automatic Virtual Environment

Attempts to Prevent Falls and Injury: A Prospective Community Study.

ERIC Educational Resources Information Center

Reinsch, Sibylle; And Others

1992-01-01

At 16 senior centers, studied effectiveness of exercise and cognitive-behavioral programs, compared to discussion control program, in reducing falls and injuries among 230 older adults. After one year of programs, observed no significant difference in time to first fall among groups. Secondary outcome measures such as strength, balance, fear of…

75 FR 6671 - Agency Forms Undergoing Paperwork Reduction Act Review

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-10

... Assessment of Fall Prevention Programs. This approval expires on 7/31/10. In June 2009, all Matter of Balance... Better Balance and Matter of Balance) and to assess the maintenance of fall prevention behaviors among participants six months after completing the Matter of Balance program. To assess the maintenance of fall...

Gait Implications of Visual Field Damage from Glaucoma.

PubMed

Mihailovic, Aleksandra; Swenor, Bonnielin K; Friedman, David S; West, Sheila K; Gitlin, Laura N; Ramulu, Pradeep Y

2017-06-01

To evaluate fall-relevant gait features in older glaucoma patients. The GAITRite Electronic Walkway was used to define fall-related gait parameters in 239 patients with suspected or manifest glaucoma under normal usual-pace walking conditions and while carrying a cup or tray. Multiple linear regression models assessed the association between gait parameters and integrated visual field (IVF) sensitivity after controlling for age, race, sex, medications, and comorbid illness. Under normal walking conditions, worse IVF sensitivity was associated with a wider base of support (β = 0.60 cm/5 dB IVF sensitivity decrement, 95% confidence interval [CI] = 0.12-1.09, P = 0.016). Worse IVF sensitivity was not associated with slower gait speed, shorter step or stride length, or greater left-right drift under normal walking conditions ( P > 0.05 for all), but was during cup and/or tray carrying conditions ( P < 0.05 for all). Worse IVF sensitivity was positively associated with greater stride-to-stride variability in step length, stride length, and stride velocity ( P < 0.005 for all). Inferior and superior IVF sensitivity demonstrated associations with each of the above gait parameters as well, though these associations were consistently similar to, or weaker than, the associations noted for overall IVF sensitivity. Glaucoma severity was associated with several gait parameters predictive of higher fall risk in prior studies, particularly measures of stride-to-stride variability. Gait may be useful in identifying glaucoma patients at higher risk of falls, and in designing and testing interventions to prevent falls in this high-risk group. These findings could serve to inform the development of the interventions for falls prevention in glaucoma patients.

Dizziness, but not falls rate, improves after routine cataract surgery: the role of refractive and spectacle changes.

PubMed

Supuk, Elvira; Alderson, Alison; Davey, Christopher J; Green, Clare; Litvin, Norman; Scally, Andrew J; Elliott, David B

2016-03-01

To determine whether dizziness and falls rates change due to routine cataract surgery and to determine the influence of spectacle type and refractive factors. Self-reported dizziness and falls were determined in 287 patients (mean age of 76.5 ± 6.3 years, 55% females) before and after routine cataract surgery for the first (81, 28%), second (109, 38%) and both eyes (97, 34%). Dizziness was determined using the short-form of the Dizziness Handicap Inventory. Six-month falls rates were determined using self-reported retrospective data. The number of patients with dizziness reduced significantly after cataract surgery (52% vs 38%; χ(2) = 19.14(,) p < 0.001), but the reduction in the number of patients who fell in the 6-months post surgery was not significant (23% vs 20%; χ(2) = 0.87, p = 0.35). Dizziness improved after first eye surgery (49% vs 33%, p = 0.01) and surgery on both eyes (58% vs 35%, p < 0.001), but not after second eye surgery (52% vs 45%, p = 0.68). Multivariate logistic regression analyses found significant links between post-operative falls and change in spectacle type (increased risk if switched into multifocal spectacles). Post-operative dizziness was associated with changes in best eye visual acuity and changes in oblique astigmatic correction. Dizziness is significantly reduced by first (or both) eye cataract surgery and this is linked with improvements in best eye visual acuity, although changes in oblique astigmatic correction increased dizziness. The lack of improvement in falls rate may be associated with switching into multifocal spectacle wear after surgery. © 2015 The Authors Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.

Development of a Fall-Risk Self-Assessment for Community-Dwelling Seniors

PubMed Central

Vivrette, Rebecca L.; Rubenstein, Laurence Z.; Martin, Jennifer L.; Josephson, Karen R.; Kramer, B. Josea

2012-01-01

Objective To determine seniors’ beliefs about falls and design a fall-risk self-assessment and educational materials to promote early identification of evidence-based fall risks and encourage prevention behaviors. Methods Focus groups with community-dwelling seniors, conducted in two phases to identify perceptions about fall risks and risk reduction and to assess face validity of the fall-risk self-assessment and acceptability of educational materials. Results Lay perception of fall risks was in general concordance with evidence-based research. Maintaining independence and positive tone were perceived as key motivators for fall prevention. Seniors intended to use information in the educational tool to stimulate discussions about falls with health care providers. Implications An evidence-based, educational fall-risk self-assessment acceptable to older adults can build on existing lay knowledge about fall risks and perception that falls are a relevant problem and can educate seniors about their specific risks and how to minimize them. PMID:21285473

Fall and Fracture Risk in Nursing Home Residents With Moderate-to-Severe Behavioral Symptoms of Alzheimer's Disease and Related Dementias Initiating Antidepressants or Antipsychotics.

PubMed

Wei, Yu-Jung; Simoni-Wastila, Linda; Lucas, Judith A; Brandt, Nicole

2017-05-01

Both antidepressants and antipsychotics are used in older adults with behavioral symptoms of Alzheimer's disease and related dementias. Despite the prevalent use of these agents, little is known about their comparative risks for falls and fractures. Using 2007-2009 Medicare claims data linked to Minimum Data Set 2.0, we identified new users of antidepressants and antipsychotics among nursing home residents with Alzheimer's disease and related dementias who had moderate-to-severe behavioral symptoms. Separate discrete-time survival models were used to estimate risks of falls, fractures, and a composite of both among antidepressant group versus antipsychotic group. Compared to antipsychotic users, antidepressant users experienced significantly higher risk for fractures (adjusted hazard ratio = 1.35, 95% confidence interval = 1.10-1.66). The overall risk of falls or fractures remained significant in the antidepressant versus antipsychotic group (adjusted hazard ratio = 1.16, 95% confidence interval = 1.02-1.32). Antidepressants are associated with higher fall and fracture risk compared to antipsychotics in the management of older adults with Alzheimer's disease and related dementias who experience moderate-to-severe behavioral symptoms. Clinicians need to assess the ongoing risks/benefits of antidepressants for these symptoms especially in light of the increasingly prevalent use of these agents. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Paintings, photographs, and computer graphics are calculated appearances

NASA Astrophysics Data System (ADS)

McCann, John

2012-03-01

Painters reproduce the appearances they see, or visualize. The entire human visual system is the first part of that process, providing extensive spatial processing. Painters have used spatial techniques since the Renaissance to render HDR scenes. Silver halide photography responds to the light falling on single film pixels. Film can only mimic the retinal response of the cones at the start of the visual process. Film cannot mimic the spatial processing in humans. Digital image processing can. This talk studies three dramatic visual illusions and uses the spatial mechanisms found in human vision to interpret their appearances.

The behavioral context of visual displays in common marmosets (Callithrix jacchus).

PubMed

de Boer, Raïssa A; Overduin-de Vries, Anne M; Louwerse, Annet L; Sterck, Elisabeth H M

2013-11-01

Communication is important in social species, and may occur with the use of visual, olfactory or auditory signals. However, visual communication may be hampered in species that are arboreal have elaborate facial coloring and live in small groups. The common marmoset fits these criteria and may have limited visual communication. Nonetheless, some (contradictive) propositions concerning visual displays in the common marmoset have been made, yet quantitative data are lacking. The aim of this study was to assign a behavioral context to different visual displays using pre-post-event-analyses. Focal observations were conducted on 16 captive adult and sub-adult marmosets in three different family groups. Based on behavioral elements with an unambiguous meaning, four different behavioral contexts were distinguished: aggression, fear, affiliation, and play behavior. Visual displays concerned behavior that included facial expressions, body postures, and pilo-erection of the fur. Visual displays related to aggression, fear, and play/affiliation were consistent with the literature. We propose that the visual display "pilo-erection tip of tail" is related to fear. Individuals receiving these fear signals showed a higher rate of affiliative behavior. This study indicates that several visual displays may provide cues or signals of particular social contexts. Since the three displays of fear elicited an affiliative response, they may communicate a request of anxiety reduction or signal an external referent. Concluding, common marmosets, despite being arboreal and living in small groups, use several visual displays to communicate with conspecifics and their facial coloration may not hamper, but actually promote the visibility of visual displays. © 2013 Wiley Periodicals, Inc.

[Study on incidence and risk factors of fall in the elderly in a rural community in Beijing].

PubMed

Zhang, D; He, Y; Liu, M; Yang, H B; Wu, L; Wang, J H; Yang, S S; Chen, J; Wang, Y Y; Zeng, J; Yao, Y; Guo, M L

2016-05-01

To investigate the incidence of fall in the old farmers of Miyun county in Beijing. The old farmers who lived in Jugezhuang and Fengjiayu townships of Miyun county were selected for a questionnaire survey to collect the information about the incidence of fall and their health status. A total of 2 397 old farmers, including 967 males and 1 430 females, were surveyed. Fall occurred in 347 old farmers(14.5%). The difference in the incidence of fall was significant between males(9.6%)and females(17.8%). A total of 282 falls occurred in courtyards, 45 falls occurred in field/hilly areas. Among the falls occurred, 216(27.2%)led to injuries. The most common site of injuries was hip(45 falls). Logistic regression analysis showed that physical exercise and high income were protective factors, but difficult standing up and walking, visual problem and stroke were the risk factors. In the males, the special risk factor was mid cognitive impairment, and in the females, the special risk factor was urinary incontinence, but afternoon nap was a protective factor. The incidence of fall in the rural community was relatively high with distinct area distribution, which has caused serious influence on the mental and physical health of the elderly.

Utilizing a Meals on Wheels program to teach falls risk assessment to medical students.

PubMed

Demons, Jamehl L; Chenna, Swapna; Callahan, Kathryn E; Davis, Brooke L; Kearsley, Linda; Sink, Kaycee M; Watkins, Franklin S; Williamson, Jeff D; Atkinson, Hal H

2014-01-01

Falls are a critical public health issue for older adults, and falls risk assessment is an expected competency for medical students. The aim of this study was to design an innovative method to teach falls risk assessment using community-based resources and limited geriatrics faculty. The authors developed a Fall Prevention Program through a partnership with Meals-on-Wheels (MOW). A 3rd-year medical student accompanies a MOW client services associate to a client's home and performs a falls risk assessment including history of falls, fear of falling, medication review, visual acuity, a Get Up and Go test, a Mini-Cog, and a home safety evaluation, reviewed in a small group session with a faculty member. During the 2010 academic year, 110 students completed the in-home falls risk assessment, rating it highly. One year later, 63 students voluntarily completed a retrospective pre/postsurvey, and the proportion of students reporting moderate to very high confidence in performing falls risk assessments increased from 30.6% to 87.3% (p < .001). Students also reported using most of the skills learned in subsequent clerkships. A single educational intervention in the MOW program effectively addressed geriatrics competencies with minimal faculty effort and could be adopted by many medical schools.

Different cognitive profiles for single compared with recurrent fallers without dementia.

PubMed

Anstey, Kaarin J; Wood, Joanne; Kerr, Graham; Caldwell, Haley; Lord, Stephen R

2009-07-01

Relationships between self-reported retrospective falls and cognitive measures (executive function, reaction time [RT], processing speed, working memory, visual attention) were examined in a population based sample of older adults (n = 658). Two of the choice RT tests involved inhibiting responses to either targets of a specific color or location with hand and foot responses. Potentially confounding demographic variables, medical conditions, and postural sway were controlled for in logistic regression models, excluding participants with possible cognitive impairment. A factor analysis of cognitive measures extracted factors measuring RT, accuracy and inhibition, and visual search. Single fallers did not differ from nonfallers in terms of health, sway or cognitive function, except that they performed worse on accuracy and inhibition. In contrast, recurrent fallers performed worse than nonfallers on all measures. Results suggest that occasional falls in late life may be associated with subtle age-related changes in the prefrontal cortex leading to failures of executive control, whereas recurrent falling may result from more advanced brain ageing that is associated with generalized cognitive decline. 2009 American Psychological Association

Ashtanga-Based Yoga Therapy Increases the Sensory Contribution to Postural Stability in Visually-Impaired Persons at Risk for Falls as Measured by the Wii Balance Board: A Pilot Randomized Controlled Trial.

PubMed

Jeter, Pamela E; Haaz Moonaz, Steffany; Bittner, Ava K; Dagnelie, Gislin

2015-01-01

Persons with visual impairment (VI) are at greater risk for falls due to irreparable damage to visual sensory input contributing to balance. Targeted training may significantly improve postural stability by strengthening the remaining sensory systems. Here, we evaluate the Ashtanga-based Yoga Therapy (AYT) program as a multi-sensory behavioral intervention to develop postural stability in VI. A randomized, waitlist-controlled, single-blind clinical trial. The trial was conducted between October 2012 and December 2013. Twenty-one legally blind participants were randomized to an 8-week AYT program (n = 11, mean (SD) age = 55(17)) or waitlist control (n=10, mean (SD) age = 55(10)). AYT subjects convened for one group session at a local yoga studio with an instructor and two individual home-based practice sessions per week for a total of 8 weeks. Subjects completed outcome measures at baseline and post-8 weeks of AYT. The primary outcome, absolute Center of Pressure (COP), was derived from the Wii Balance Board (WBB), a standalone posturography device, in 4 sensory conditions: firm surface, eyes open (EO); firm surface, eyes closed (EC); foam surface, EO; and foam surface, EC. Stabilization Indices (SI) were computed from COP measures to determine the relative visual (SIfirm, SIfoam), somatosensory (SIEO, SIEC) and vestibular (SIV, i.e., FoamEC vs. FirmEO) contributions to balance. This study was not powered to detect between group differences, so significance of pre-post changes was assessed by paired samples t-tests within each group. Groups were equivalent at baseline (all p > 0.05). In the AYT group, absolute COP significantly increased in the FoamEO (t(8) = -3.66, p = 0.01) and FoamEC (t(8) = -3.90, p = 0.01) conditions. Relative somatosensory SIEO (t(8) = -2.42, p = 0.04) and SIEC (t(8) = -3.96, p = 0.01), and vestibular SIV (t(8) = -2.47, p = 0.04) contributions to balance increased significantly. As expected, no significant changes from EO to EC conditions were found indicating an absence of visual dependency in VI. No significant pre-post changes were observed in the control group (all p > 0.05). These preliminary results establish the potential for AYT training to develop the remaining somatosensory and vestibular responses used to optimize postural stability in a VI population. www.ClinicalTrials.gov NCT01366677.

Ashtanga-Based Yoga Therapy Increases the Sensory Contribution to Postural Stability in Visually-Impaired Persons at Risk for Falls as Measured by the Wii Balance Board: A Pilot Randomized Controlled Trial

PubMed Central

Haaz Moonaz, Steffany; Bittner, Ava K.

2015-01-01

Objective Persons with visual impairment (VI) are at greater risk for falls due to irreparable damage to visual sensory input contributing to balance. Targeted training may significantly improve postural stability by strengthening the remaining sensory systems. Here, we evaluate the Ashtanga-based Yoga Therapy (AYT) program as a multi-sensory behavioral intervention to develop postural stability in VI. Design A randomized, waitlist-controlled, single-blind clinical trial Methods The trial was conducted between October 2012 and December 2013. Twenty-one legally blind participants were randomized to an 8-week AYT program (n = 11, mean (SD) age = 55(17)) or waitlist control (n=10, mean (SD) age = 55(10)). AYT subjects convened for one group session at a local yoga studio with an instructor and two individual home-based practice sessions per week for a total of 8 weeks. Subjects completed outcome measures at baseline and post-8 weeks of AYT. The primary outcome, absolute Center of Pressure (COP), was derived from the Wii Balance Board (WBB), a standalone posturography device, in 4 sensory conditions: firm surface, eyes open (EO); firm surface, eyes closed (EC); foam surface, EO; and foam surface, EC. Stabilization Indices (SI) were computed from COP measures to determine the relative visual (SIfirm, SIfoam), somatosensory (SIEO, SIEC) and vestibular (SIV, i.e., FoamEC vs. FirmEO) contributions to balance. This study was not powered to detect between group differences, so significance of pre-post changes was assessed by paired samples t-tests within each group. Results Groups were equivalent at baseline (all p > 0.05). In the AYT group, absolute COP significantly increased in the FoamEO (t(8) = -3.66, p = 0.01) and FoamEC (t(8) = -3.90, p = 0.01) conditions. Relative somatosensory SIEO (t(8) = -2.42, p = 0.04) and SIEC (t(8) = -3.96, p = 0.01), and vestibular SIV (t(8) = -2.47, p = 0.04) contributions to balance increased significantly. As expected, no significant changes from EO to EC conditions were found indicating an absence of visual dependency in VI. No significant pre-post changes were observed in the control group (all p > 0.05). Conclusions These preliminary results establish the potential for AYT training to develop the remaining somatosensory and vestibular responses used to optimize postural stability in a VI population. Trial Registration www.ClinicalTrials.gov NCT01366677 PMID:26107256

Hospitalizations for fall-related injuries among active-duty Army soldiers, 1980–1998

PubMed Central

Senier, Laura; Bell, Nicole S.; Yore, Michelle M.; Amoroso, Paul J.

2007-01-01

Data from the Total Army Injury and Health Outcomes Database (TAIHOD) were used to describe 28,352 fall-related hospitalizations among active-duty Army soldiers between 1980 and 1998. Soldiers who were younger than age 26, single, and had a high school education or less were at greatest risk. Falls from a height were more likely to be fatal than other types of falls, accounting for 88% of all fatalities. In cases where duty status was known, 64% of the falls took place while the soldier was on duty and half of these occurred during training. The most common type of fall during training was fall from a height (37%). Falls on stairs and ladders accounted for 49% of all off-duty falls. Future research should include identification of specific behavioral and occupational risk factors for falls, particularly those occurring during training activities, and falls occurring off duty. PMID:12441580

Relations between postural stability, gait and falls in elderly persons--preliminary report.

PubMed

Baczkowicz, Dawid; Szczegielniak, Jan; Proszkowiec, Małgorzata

2008-01-01

Balance control in elderly patients is the area of interest of many researchers. The results of their studies suggest that the measurement of shifts in the centre of foot pressure on the support base (COP) can be used as a tool for identification of fall-prone persons. It is interesting whether there are any relations between functional status, gait, posture stability and the risk of falling. The aim of this study was to find the answer to this question. The study involved 20 patients (mean age 78.1+/-11.6). The functional status of the patients was evaluated according to the Barthel Index. Postural stability was assessed with the use of a Neurocom Balance Master platform. Three measurements were taken with visual feedback (eyes open-EO) and three without visual feedback (eyes closed-EC). Balance control was also evaluated with the Berg test and on the basis of the history of episodes of falling in the preceding six months. Gait was evaluated with the six-minute walking test. The parameters recorded by the force platform showed a significant relation to the values obtained in the Berg test (r=-0.60; p<0.001 for EO and r=-0.58; p<0.001 for EC). Similar trends were noted for the relation between EO and distance/velocity as well as functional status (r=-0.63 and -0.68; p<0.001). On the other hand the number of falls showed a significant relation only to the EO test (r=0.4; p<0.05). 1. An evaluation of balance control with a force platform and the Berg test produced convergent results. 2. The incidence of falls was connected with increased body sway. 3. The functional status of the patient and the balance control evaluation according to the Berg test failed to determine the risk of falling. 4. A relation was observed between postural stability, functional status and gait.

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

PubMed

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

2015-09-01

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

Adaptive Behavior of Primary School Students with Visual Impairments: The Impact of Educational Settings

ERIC Educational Resources Information Center

Metsiou, Katerina; Papadopoulos, Konstantinos; Agaliotis, Ioannis

2011-01-01

This study explored the adaptive behavior of primary school students with visual impairments, as well as the impact of educational setting on their adaptive behavior. Instrumentation included an informal questionnaire and the Vineland Adaptive Behavior Scales. Participants were 36 primary school students with visual impairments. The educational…

Lateral step initiation behavior in older adults.

PubMed

Sparto, Patrick J; Jennings, J Richard; Furman, Joseph M; Redfern, Mark S

2014-02-01

Older adults have varied postural responses during induced and voluntary lateral stepping. The purpose of the research was to quantify the occurrence of different stepping strategies during lateral step initiation in older adults and to relate the stepping responses to retrospective history of falls. Seventy community-ambulating older adults (mean age 76 y, range 70-94 y) performed voluntary lateral steps as quickly as possible to the right or left in response to a visual cue, in a blocked design. Vertical ground reaction forces were measured using a forceplate, and the number and latency of postural adjustments were quantified. Subjects were assigned to groups based on their stepping strategy. The frequency of trials with one or two postural adjustments was compared with data from 20 younger adults (mean age 38 y, range 21-58 y). Logistic regression was used to relate presence of a fall in the previous year with the number and latency of postural adjustments. In comparison with younger adults, who almost always demonstrated one postural adjustment when stepping laterally, older adults constituted a continuous distribution in the percentage of step trials made with one postural adjustment (from 0% to 100% of trials). Latencies of the initial postural adjustment and foot liftoff varied depending on the number of postural adjustments made. A history of falls was associated a larger percentage of two postural adjustments, and a longer latency of foot liftoff. In conclusion, the number and latency of postural adjustments made during voluntary lateral stepping provides additional evidence that lateral control of posture may be a critical indicator of aging. Copyright © 2013 Elsevier B.V. All rights reserved.

Lateral step initiation behavior in older adults

PubMed Central

Sparto, Patrick J; Jennings, J Richard; Furman, Joseph M; Redfern, Mark S

2013-01-01

Older adults have varied postural responses during induced and voluntary lateral stepping. The purpose of the research was to quantify the occurrence of different stepping strategies during lateral step initiation in older adults and to relate the stepping responses to retrospective history of falls. Seventy community-ambulating older adults (mean age 76 y, range 70–94 y) performed voluntary lateral steps as quickly as possible to the right or left in response to a visual cue, in a blocked design. Vertical ground reaction forces were measured using a forceplate, and the number and latency of postural adjustments were quantified. Subjects were assigned to groups based on their stepping strategy. The frequency of trials with one or two postural adjustments was compared with data from 20 younger adults (mean age 38 y, range 21–58 y). Logistic regression was used to relate presence of a fall in the previous year with the number and latency of postural adjustments. In comparison with younger adults, who almost always demonstrated one postural adjustment when stepping laterally, older adults constituted a continuous distribution in the percentage of step trials made with one postural adjustment (from 0% to 100% of trials). Latencies of the initial postural adjustment and foot liftoff varied depending on the number of postural adjustments made. A history of falls was associated a larger percentage of two postural adjustments, and a longer latency of foot liftoff. In conclusion, the number and latency of postural adjustments made during voluntary lateral stepping provides additional evidence that lateral control of posture may be a critical indicator of aging. PMID:24295896

Developing fall armyworms as a model for studying the migratory behavior of lepidopteran pests in the United States.

USDA-ARS?s Scientific Manuscript database

The fall armyworm, Spodoptera frugiperda (J. E. Smith) is a significant economic pest in the western hemisphere, causing substantial losses in corn, sorghum, forage and turf grasses . Although fall armyworm does not survive severe winters, it infests most of the central and eastern United States an...

A novel video-based paradigm to study the mechanisms underlying age- and falls risk-related differences in gaze behaviour during walking.

PubMed

Stanley, Jennifer; Hollands, Mark

2014-07-01

The current study aimed to quantitatively assess differences in gaze behaviour between participants grouped on the basis of their age and measures of functional mobility during a virtual walking paradigm. The gaze behaviour of nine young adults, seven older adults with a relatively low risk of falling and seven older adults with a relatively higher risk of falling was measured while they watched five first-person perspective movies representing the viewpoint of a pedestrian walking through various environments. Participants also completed a number of cognitive tests: Stroop task, visual search, trail making task, Mini Mental Status Examination, and reaction time, visual tests (visual acuity and contrast sensitivity) and assessments of balance (Activities Balance Confidence Scale and Berg Balance Scale) to aid in the interpretation of differences in gaze behaviour. The high risk older adult group spent significantly more time fixating aspects of the travel path than the low risk and young adult groups. High risk older adults were also significantly slower in performing a number of the cognitive tasks than young adults. Correlations were conducted to compare the extent to which travel path fixation durations co-varied with scores on the tests of visual search, motor, and cognitive function. A positive significant correlation was found between the speed of response to the incongruent Stroop task and travel path fixation duration r21  = 0.44, p < 0.05. The results indicate that our movie-viewing paradigm can identify differences in gaze behaviour between participants grouped on the basis of their age and measures of functional mobility and that these differences are associated with cognitive decline. © 2014 The Authors Ophthalmic & Physiological Optics © 2014 The College of Optometrists.

Evaluation and refinement of a handheld health information technology tool to support the timely update of bedside visual cues to prevent falls in hospitals.

PubMed

Teh, Ruth C-A; Visvanathan, Renuka; Ranasinghe, Damith; Wilson, Anne

2018-06-01

To evaluate clinicians' perspectives, before and after clinical implementation (i.e. trial) of a handheld health information technology (HIT) tool, incorporating an iPad device and automatically generated visual cues for bedside display, for falls risk assessment and prevention in hospital. This pilot study utilized mixed-methods research with focus group discussions and Likert-scale surveys to elicit clinicians' attitudes. The study was conducted across three phases within two medical wards of the Queen Elizabeth Hospital. Phase 1 (pretrial) involved focus group discussion (five staff) and surveys (48 staff) to elicit preliminary perspectives on tool use, benefits and barriers to use and recommendations for improvement. Phase 2 (tool trial) involved HIT tool implementation on two hospital wards over consecutive 12-week periods. Phase 3 (post-trial) involved focus group discussion (five staff) and surveys (29 staff) following tool implementation, with similar themes as in Phase 1. Qualitative data were evaluated using content analysis, and quantitative data using descriptive statistics and logistic regression analysis, with subgroup analyses on user status (P ≤ 0.05). Four findings emerged on clinicians' experience, positive perceptions, negative perceptions and recommendations for improvement of the tool. Pretrial, clinicians were familiar with using visual cues in hospital falls prevention. They identified potential benefits of the HIT tool in obtaining timely, useful falls risk assessment to improve patient care. During the trial, the wards differed in methods of tool implementation, resulting in lower uptake by clinicians on the subacute ward. Post-trial, clinicians remained supportive for incorporating the tool into clinical practice; however, there were issues with usability and lack of time for tool use. Staff who had not used the tool had less appreciation for it improving their understanding of patients' falls risk factors (odds ratio 0.12), or effectively preventing hospital falls (odds ratio 0.12). Clinicians' recommendations resulted in subsequent technological refinement of the tool, and provision of an additional iPad device for more efficient use. This study adds to the limited pool of knowledge about clinicians' attitudes toward health technology use in falls avoidance. Clinicians were willing to use the HIT tool, and their concerns about its usability were addressed in ongoing tool improvement. Including end-users in the development and refinement processes, as well as having high staff uptake of new technologies, is important in improving their acceptance and usage, and in maximizing beneficial feedback to further inform tool development.

Where attention falls: Increased risk of falls from the converging impact of cortical cholinergic and midbrain dopamine loss on striatal function.

PubMed

Sarter, Martin; Albin, Roger L; Kucinski, Aaron; Lustig, Cindy

2014-07-01

Falls are a major source of hospitalization, long-term institutionalization, and death in older adults and patients with Parkinson's disease (PD). Limited attentional resources are a major risk factor for falls. In this review, we specify cognitive-behavioral mechanisms that produce falls and map these mechanisms onto a model of multi-system degeneration. Results from PET studies in PD fallers and findings from a recently developed animal model support the hypothesis that falls result from interactions between loss of basal forebrain cholinergic projections to the cortex and striatal dopamine loss. Striatal dopamine loss produces inefficient, low-vigor gait, posture control, and movement. Cortical cholinergic deafferentation impairs a wide range of attentional processes, including monitoring of gait, posture and complex movements. Cholinergic cell loss reveals the full impact of striatal dopamine loss on motor performance, reflecting loss of compensatory attentional supervision of movement. Dysregulation of dorsomedial striatal circuitry is an essential, albeit not exclusive, mediator of falls in this dual-system model. Because cholinergic neuromodulatory activity influences cortical circuitry primarily via stimulation of α4β2* nicotinic acetylcholine receptors, and because agonists at these receptors are known to benefit attentional processes in animals and humans, treating PD fallers with such agonists, as an adjunct to dopaminergic treatment, is predicted to reduce falls. Falls are an informative behavioral endpoint to study attentional-motor integration by striatal circuitry. Copyright © 2014 Elsevier Inc. All rights reserved.

Where attention falls: Increased risk of falls from the converging impact of cortical cholinergic and midbrain dopamine loss on striatal function

PubMed Central

Sarter, Martin; Albin, Roger L.; Kucinski, Aaron; Lustig, Cindy

2015-01-01

Falls are a major source of hospitalization, long-term institutionalization, and death in older adults and patients with Parkinson’s disease (PD). Limited attentional resources are a major risk factor for falls. In this review, we specify cognitive–behavioral mechanisms that produce falls and map these mechanisms onto a model of multi-system degeneration. Results from PET studies in PD fallers and findings from a recently developed animal model support the hypothesis that falls result from interactions between loss of basal forebrain cholinergic projections to the cortex and striatal dopamine loss. Striatal dopamine loss produces inefficient, low-vigor gait, posture control, and movement. Cortical cholinergic deafferentation impairs a wide range of attentional processes, including monitoring of gait, posture and complex movements. Cholinergic cell loss reveals the full impact of striatal dopamine loss on motor performance, reflecting loss of compensatory attentional supervision of movement. Dysregulation of dorsomedial striatal circuitry is an essential, albeit not exclusive, mediator of falls in this dual-system model. Because cholinergic neuromodulatory activity influences cortical circuitry primarily via stimulation of α4β2* nicotinic acetylcholine receptors, and because agonists at these receptors are known to benefit attentional processes in animals and humans, treating PD fallers with such agonists, as an adjunct to dopaminergic treatment, is predicted to reduce falls. Falls are an informative behavioral endpoint to study attentional–motor integration by striatal circuitry. PMID:24805070

A SURVEY OF VISUAL AIDS IN SCHOOLS AND CLASSES FOR THE DEAF IN THE UNITED STATES.

ERIC Educational Resources Information Center

KUBIS, JOHN J.; SCHEIN, JEROME D.

INFORMATION CONCERNING VISUAL PRESENTATION DEVICES, THEIR USE IN THE EDUCATION OF THE DEAF, AND THEIR SPECIAL PROBLEMS WERE SURVEYED. QUESTIONNAIRES WERE SENT TO ALL SCHOOLS AND CLASSES FOR THE DEAF IN THE UNITED STATES DURING THE FALL SEMESTER OF 1961-62. THE RESPONSE WAS 55.9 PERCENT OF THE QUESTIONNAIRES MAILED. INTERVIEWS WERE HELD WITH A…

NAVO MSRC Navigator. Fall 2001

DTIC Science & Technology

2001-01-01

of the CAVE. A view from the VR Juggler simulator . The particles indicate snow (white) & ice (blue). Rainfall is shown on the terrain, and clouds as...the Cover: Virtual environment built by the NAVO MSRC Visualization Center for the Concurrent Computing Laboratory for Materials Simulation at...Louisiana State University. This application allows the researchers to visualize a million atom simulation of an indentor puncturing a block of gallium

[Establishment and application effect of fall prevention and control information system in elderly community].

PubMed

Zhao, Ting; Pi, Hong-Ying; Ku, Hong-An; Pan, Li; Gong, Zhu-Yun

2018-02-08

To investigate establishing, applying and evaluating the fall prevention and control information system in elderly community. Relying on internet technology and informatization means, the fall comprehensive prevention and control strategy of elderly was guided into online from offline. The fall prevention and control information system which was a collection of risk assessment, remote education and feedback was established. One hundred and twenty-six elderly (over 60 years old) in community were screened in this study and 84 high-risk elders who were involved in the remote continuous comprehensive intervention were screened out. Intervening measures included distributing propaganda album, making mission slides and video used to play with the interpretation remotely. Then fall related situation before and after intervention was analyzed and the effectiveness of system evaluated. After remote intervention, the fall incidence of high-risk group decreased from 21.43% to 4.76%( P <0.01). The body balance and gait stability improved clearly( P <0. 01). The rate of taking proper prevention and control behavior significantly improved( P <0.01). They believed in themselves not to fall down with more confidence when taking complex behaviors( P <0.01). The security of environment at home significantly enhanced( P <0. 01). Fall prevention and control information system in elderly community was innovative and convenient. The system could roundly assess the status related to fall and accurately screen out high-risk group. The system could implement the remote continuous comprehensive intervention so that the incident of fall was decrease. In conclusion, the system is stable and effective, can be further popularization and application as a successful pilot.

Anticipating the effects of visual gravity during simulated self-motion: estimates of time-to-passage along vertical and horizontal paths.

PubMed

Indovina, Iole; Maffei, Vincenzo; Lacquaniti, Francesco

2013-09-01

By simulating self-motion on a virtual rollercoaster, we investigated whether acceleration cued by the optic flow affected the estimate of time-to-passage (TTP) to a target. In particular, we studied the role of a visual acceleration (1 g = 9.8 m/s(2)) simulating the effects of gravity in the scene, by manipulating motion law (accelerated or decelerated at 1 g, constant speed) and motion orientation (vertical, horizontal). Thus, 1-g-accelerated motion in the downward direction or decelerated motion in the upward direction was congruent with the effects of visual gravity. We found that acceleration (positive or negative) is taken into account but is overestimated in module in the calculation of TTP, independently of orientation. In addition, participants signaled TTP earlier when the rollercoaster accelerated downward at 1 g (as during free fall), with respect to when the same acceleration occurred along the horizontal orientation. This time shift indicates an influence of the orientation relative to visual gravity on response timing that could be attributed to the anticipation of the effects of visual gravity on self-motion along the vertical, but not the horizontal orientation. Finally, precision in TTP estimates was higher during vertical fall than when traveling at constant speed along the vertical orientation, consistent with a higher noise in TTP estimates when the motion violates gravity constraints.

Assessing balance through the use of a low-cost head-mounted display in older adults: a pilot study.

PubMed

Saldana, Santiago J; Marsh, Anthony P; Rejeski, W Jack; Haberl, Jack K; Wu, Peggy; Rosenthal, Scott; Ip, Edward H

2017-01-01

As the population ages, the prevention of falls is an increasingly important public health problem. Balance assessment forms an important component of fall-prevention programs for older adults. The recent development of cost-effective and highly responsive virtual reality (VR) systems means new methods of balance assessment are feasible in a clinical setting. This proof-of-concept study made use of the submillimeter tracking built into modern VR head-mounted displays (VRHMDs) to assess balance through the use of visual-vestibular conflict. The objective of this study was to evaluate the validity, acceptability, and reliability of using a VRHMD to assess balance in older adults. Validity was assessed by comparing measurements from the VRHMD to measurements of postural sway from a force plate. Acceptability was assessed through the use of the Simulator Sickness Questionnaire pre- and postexposure to assess possible side effects of the visual-vestibular conflict. Reliability was assessed by measuring correlations between repeated measurements 1 week apart. Variables of possible importance that were found to be reliable ( r ≥0.9) between tests separated by a week were then tested for differences compared to a control group. Assessment was performed as a cross-sectional single-site community center-based study in 13 older adults (≥65 years old, 80.2±7.3 years old, 77% female, five at risk of falls, eight controls). The VR balance assessment consisted of four modules: a baseline module, a reaction module, a balance module, and a seated assessment. There was a significant difference in the rate at which participants with a risk of falls changed their tilt in the anteroposterior direction compared to the control group. Participants with a risk of falls changed their tilt in the anteroposterior direction at 0.7°/second vs 0.4°/second for those without a history of falls. No significant differences were found between pre/postassessment for oculomotor score or total Simulator Sickness Questionnaire score. Both the force plate and the head-mounted display balance-assessment system were able to detect differences between conditions meant to mask visual and proprioceptive information. This VRHMD is both affordable and portable, causes minimal simulator sickness, and produces repeatable results that can be used to assess balance in older adults.

Identifying Balance Measures Most Likely to Identify Recent Falls.

PubMed

Criter, Robin E; Honaker, Julie A

2016-01-01

Falls sustained by older adults are an increasing health care issue. Early identification of those at risk for falling can lead to successful prevention of falls. Balance complaints are common among individuals who fall or are at risk for falling. The purpose of this study was to evaluate the clinical utility of a multifaceted balance protocol used for fall risk screening, with the hypothesis that this protocol would successfully identify individuals who had a recent fall (within the previous 12 months). This is a retrospective review of 30 individuals who self-referred for a free fall risk screening. Measures included case history, Activities-Specific Balance Confidence Scale, modified Clinical Test of Sensory Interaction on Balance, Timed Up and Go test, and Dynamic Visual Acuity. Statistical analyses were focused on the ability of the test protocol to identify a fall within the past 12 months and included descriptive statistics, clinical utility indices, logistic regression, receiver operating characteristic curve, area under the curve analysis, effect size (Cohen d), and Spearman correlation coefficients. All individuals who self-referred for this free screening had current imbalance complaints, and were typically women (70%), had a mean age of 77.2 years, and had a fear of falling (70%). Almost half (46.7%) reported at least 1 lifetime fall and 40.0% within the past 12 months. Regression analysis suggested that the Timed Up and Go test was the most important indicator of a recent fall. A cutoff score of 12 or more seconds was optimal (sensitivity: 83.3%; specificity: 61.1%). Older adults with current complaints of imbalance have a higher rate of falls, fall-related injury, and fear of falling than the general community-dwelling public. The Timed Up and Go test is useful for determining recent fall history in individuals with imbalance.

[Evaluation of postural control systems in elderly patients with repeated falls].

PubMed

González Ramírez, Alfonso; Lázaro del Nogal, Montserrat; Ribera Casado, José Manuel

2008-01-01

a) to describe postural control disorders in elderly patients with recurrent falls; b) to analyze the influence of sensory deficits on centre of gravity control mechanisms; and c) to assess the functional consequences of balance disorders and falls in this group of patients. patients aged more than 65 years old referred to a falls unit with two or more falls in the previous 6 months were included in this study. The protocol included posturographic studies with a Neurocom Balance Master. To evaluate motor control, Rhythmic Weight Shift (RWS test) was performed. To assess sensorial control, Modified Clinical Test of Sensory Interaction on Balance (MCT test) was used. Other tests performed were the Sit to Stand (SS test), Walk across (WA test) and Step up over (SO test). a total of 109 patients (85.3% women) were studied. Mean age was 78.01 years (SD: 5.38). Disorders in one or more afferent sensorial systems were found in 51.7% of the patients (27.5% visual deficiencies, 17.6% vestibular alterations, and 6.6% somatosensorial deficits). Two afferent systems were compromised in 25.3%, and all three were compromised in 11.1% of the patients. No significant differences were found in directional control (RWS) when compared with the number of altered systems. posturographic studies provide sensitive information on static and dynamic centre of gravity control systems, eventual sensory deficits, and patients' ability to carry out basic activities of daily living. In our sample, the most frequent deficit was visual impairment. This information is essential to establish a correct management programme.

The role of culture and diversity in the prevention of falls among older Chinese people.

PubMed

Horton, Khim; Dickinson, Angela

2011-03-01

This grounded-theory study explored the perceptions of Chinese older people, living in England, on falls and fear of falling, and identified facilitators and barriers to fall prevention interventions. With a sample of 30 Chinese older people, we conducted two focus groups and 10 in-depth interviews in Mandarin or Cantonese. Interview transcripts, back translated, were analyzed using N6. Constant comparative analysis highlighted a range of health-seeking behaviors after a fall: Chinese older people were reluctant to use formal health services; talking about falls was avoided; older people hid falls from their adult children to avoid worrying them; and fatalistic views about falls and poor knowledge about availability and content of interventions were prevalent. Cost of interventions was important. Chinese older adults valued their independence, and cultural intergenerational relations had an impact on taking action to prevent falls. Cultural diversity affects older adults' acceptance of fall prevention interventions.

An integrative model of risk for high school disordered eating.

PubMed

Davis, Heather A; Smith, Gregory T

2018-06-21

Binge eating and purging behaviors are associated with significant harm and distress among adolescents. The process by which these behaviors develop (often in the high school years) is not fully understood. We tested the Acquired Preparedness (AP) model of risk involving transactions among biological, personality, and psychosocial factors to predict binge eating and purging behavior in a sample of 1,906 children assessed in the spring of 5th grade (the last year of elementary school), the fall of 6th grade (the first year of middle school), spring of 6th grade, and spring of 10th grade (second year of high school). Pubertal onset in spring of 5th grade predicted increases in negative urgency, but not negative affect, in the fall of 6th grade. Negative urgency in the fall of 6th grade predicted increases in expectancies for reinforcement from eating in the spring of 6th grade, which in turn predicted increases in binge eating behavior in the spring of 10th grade. Negative affect in the fall of 6th grade predicted increases in thinness expectancies in the spring of 6th grade, which in turn predicted increases in purging in the spring of 10th grade. Results demonstrate similarities and differences in the development of these two different bulimic behaviors. Intervention efforts targeting the risk factors evident in this model may prove fruitful in the treatment of eating disorders characterized by binge eating and purging. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

State Defense Force Monograph Series. Fall 2007, Special Units

DTIC Science & Technology

2007-01-01

authors and the visual panorama of artists and film makers. Those World War Two soldiers for whom “taps” has not yet been sounded may still remember the...Defense Force Monograph Series, Fall 2007, SPECIAL UNITS The Primary Zone will encompass the direct blast and thermal effects of the detonation and also...structural damage and the immediate fires from the thermal effects, although there may be secondary fires outside the Primary Zone. For a 10kt

Incidence and related clinical factors of falls among older Chinese veterans in military communities: a prospective study.

PubMed

Xu, Wei; Chen, Da-Wei; Jin, Yan-Bin; Dong, Zhen-Jun; Zhang, Wei-Jiang; Chen, Jin-Wen; Yang, Shu-Mei; Wang, Jian-Rong

2015-02-01

[Purpose] The aim of this study was to determine fall incidence and explore clinical factors of falls among older Chinese veterans in military communities. [Subjects and Methods] We carried out a 12-month prospective study among 13 military communities in Beijing, China. Fall events were obtained by self-report to military community liaisons and monthly telephone interviews by researchers. [Results] Among the final sample of 447 older veterans, 86 fell once, 25 fell twice or more, and 152 falls occurred altogether. The incidence of falls and fallers were 342/1,000 person-years and 249/1,000 person-years. In Cox regression models, independent clinical factors associated with falls were visual acuity (RR=0.47), stroke (RR=2.43), lumbar diseases (RR=1.73), sedatives (RR=1.80), fall history in the past 6 months (RR=2.77), multiple chronic diseases (RR=1.53), multiple medications (RR=1.34), and five-repetition sit-to-stand test score (RR=1.41). Hearing acuity was close to being statistically significant. [Conclusion] The incidences of falls and fallers among older Chinese veterans were lower than those of Hong Kong and western countries. The clinical risk factors of falls were poor senses, stroke, lumbar diseases, taking sedatives, fall history in the past 6 months, having multiple chronic diseases, taking multiple medications, and poor physical function. The preventive strategies targeting the above risk factors are very significant for reducing falls.

Incidence and related clinical factors of falls among older Chinese veterans in military communities: a prospective study

PubMed Central

Xu, Wei; Chen, Da-Wei; Jin, Yan-Bin; Dong, Zhen-Jun; Zhang, Wei-Jiang; Chen, Jin-Wen; Yang, Shu-Mei; Wang, Jian-Rong

2015-01-01

[Purpose] The aim of this study was to determine fall incidence and explore clinical factors of falls among older Chinese veterans in military communities. [Subjects and Methods] We carried out a 12-month prospective study among 13 military communities in Beijing, China. Fall events were obtained by self-report to military community liaisons and monthly telephone interviews by researchers. [Results] Among the final sample of 447 older veterans, 86 fell once, 25 fell twice or more, and 152 falls occurred altogether. The incidence of falls and fallers were 342/1,000 person-years and 249/1,000 person-years. In Cox regression models, independent clinical factors associated with falls were visual acuity (RR=0.47), stroke (RR=2.43), lumbar diseases (RR=1.73), sedatives (RR=1.80), fall history in the past 6 months (RR=2.77), multiple chronic diseases (RR=1.53), multiple medications (RR=1.34), and five-repetition sit-to-stand test score (RR=1.41). Hearing acuity was close to being statistically significant. [Conclusion] The incidences of falls and fallers among older Chinese veterans were lower than those of Hong Kong and western countries. The clinical risk factors of falls were poor senses, stroke, lumbar diseases, taking sedatives, fall history in the past 6 months, having multiple chronic diseases, taking multiple medications, and poor physical function. The preventive strategies targeting the above risk factors are very significant for reducing falls. PMID:25729162

[Posture and gait disorders and the incidence of falling in patients with Parkinson].

PubMed

Cano-de la Cuerda, R; Macías-Jiménez, A I; Cuadrado-Pérez, M L; Miangolarra-Page, J C; Morales-Cabezas, M

Although falls are one of the main causes of morbidity and mortality in patients with Parkinson's disease, studies about its incidence and predicting factors are scarce. Our study involved 25 patients with PD (15 males and 10 females; age: 75.8 +/- 6.5 years). A closed survey was used to determine a retrospective record of falls during the last year. An analysis was performed to examine whether there was a relationship with Hoehn and Yahr staging, the score on the Up and Go scale or the Barthel index and with possible risk factors for falls. All the patients had suffered falls at some time over the last year (mean number of falls: 6.5 +/- 3.8). 56% of the falls happened during the phases of the day when patient mobility was at its highest. A significant correlation was found between the number of falls and the Hoehn and Yahr and the Up and Go scores. The number of falls was significantly higher in patients with loss of postural reflexes, the need for help in order to walk, and blockage and festination phenomena. No association was found with fear of falling, visual alterations or postural lateralisation. Association with the Barthel index and dependence for activities of daily living reached almost significant levels. Postural instability and disorders affecting gait appear to be the factors that give patients with PD a greater propensity to fall. Patients who present such alterations should be submitted to rehabilitation therapy aimed at preventing them from falling.

Analysis of Choice Stepping with Visual Interference Can Detect Prolonged Postural Preparation in Older Adults with Mild Cognitive Impairment at High Risk of Falling.

PubMed

Uemura, Kazuki; Hasegawa, Takashi; Tougou, Hiroki; Shuhei, Takahashi; Uchiyama, Yasushi

2015-01-01

We aimed to clarify postural control deficits in older adults with mild cognitive impairment (MCI) at high risk of falling by addressing the inhibitory process. This study involved 376 community-dwelling older adults with MCI. Participants were instructed to execute forward stepping on the side indicated by the central arrow while ignoring the 2 flanking arrows on each side (→→→→→, congruent, or →→←→→, incongruent). Initial weight transfer direction errors [anticipatory postural adjustment (APA) errors], step execution times, and divided phases (reaction, APA, and swing phases) were measured from vertical force data. Participants were categorized as fallers (n = 37) and non-fallers (n = 339) based on fall experiences in the last 12 months. There were no differences in the step execution times, swing phases, step error rates, and APA error rates between groups, but fallers had a significantly longer APA phase relative to non-fallers in trials of the incongruent condition with APA errors (p = 0.005). Fallers also had a longer reaction phase in trials with the correct APA, regardless of the condition (p = 0.01). Analyses of choice stepping with visual interference can detect prolonged postural preparation as a specific falling-associated deficit in older adults with MCI. © 2015 S. Karger AG, Basel.

Older Adults' Opinions on Fall Prevention in Relation to Physical Activity Level.

PubMed

Tuvemo Johnson, Susanna; Martin, Cathrin; Anens, Elisabeth; Johansson, Ann-Christin; Hellström, Karin

2018-01-01

The purpose of this study was to explore and describe older adults' opinions regarding actions to prevent falls and to analyze differences in the opinions of highly versus less physically active older adults. An open-ended question was answered by 262 individuals aged 75 to 98 years living in the community. The answers were analyzed using qualitative content analysis, and differences in the categories were compared between highly and less physically active persons. Physical activity was measured according to a five-level scale. The content analysis resulted in eight categories: assistive devices, avoiding hazards, behavioral adaptive strategies, being physically active, healthy lifestyle, indoor modifications, outdoor modifications, and seeking assistance. Behavioral adaptive strategies were mentioned to a greater extent by highly active people, and indoor modifications were more often mentioned by less active older adults. Support for active self-directed behavioral strategies might be important for fall prevention among less physically active older adults.

Stick balancing, falls and Dragon-Kings

NASA Astrophysics Data System (ADS)

Cabrera, J. L.; Milton, J. G.

2012-05-01

The extent to which the occurrence of falls, the dominant feature of human attempts to balance a stick at their fingertip, can be predicted is examined in the context of the "Dragon-King" hypothesis. For skilled stick balancers, fluctuations in the controlled variable, namely the vertical displacement angle θ, exhibit power law behaviors. When stick balancing is made less stable by either decreasing the length of the stick or by requiring the subject to balance the stick on the surface of a table tennis racket, systematic departures from the power law behaviors are observed in the range of large θ. This observation raises the possibility that the presence of departures from the power law in the large length scale region, possibly Dragon-Kings, may identify situations in which the occurrence of a fall is more imminent. However, whether or not Dragon-Kings are observed, there is a Weibull-type survival function for stick falling. The possibility that increased risk of falling can, at least to some extent, be predicted from fluctuations in the controlled variable before the event occurs has important implications for the development of preventative strategies for the management of phenomena ranging from earthquakes to epileptic seizures to falls in the elderly.

Identification of non-visual photomotor response cells in the vertebrate hindbrain

PubMed Central

Kokel, David; Dunn, Timothy W.; Ahrens, Misha B.; Alshut, Rüdiger; Cheung, Chung Yan J.; Saint-Amant, Louis; Bruni, Giancarlo; Mateus, Rita; van Ham, Tjakko J.; Shiraki, Tomoya; Fukada, Yoshitaka; Kojima, Daisuke; Yeh, Jing-Ruey J.; Mikut, Ralf; von Lintig, Johannes; Engert, Florian; Peterson, Randall T.

2013-01-01

Non-visual photosensation enables animals to sense light without sight. However, the cellular and molecular mechanisms of non-visual photobehaviors are poorly understood, especially in vertebrate animals. Here, we describe the photomotor response (PMR), a robust and reproducible series of motor behaviors in zebrafish that is elicited by visual wavelengths of light, but does not require the eyes, pineal gland or other canonical deep-brain photoreceptive organs. Unlike the relatively slow effects of canonical non-visual pathways, motor circuits are strongly and quickly (seconds) recruited during the PMR behavior. We find that the hindbrain is both necessary and sufficient to drive these behaviors. Using in vivo calcium imaging, we identify a discrete set of neurons within the hindbrain whose responses to light mirror the PMR behavior. Pharmacological inhibition of the visual cycle blocks PMR behaviors, suggesting that opsin-based photoreceptors control this behavior. These data represent the first known light-sensing circuit in the vertebrate hindbrain. PMID:23447595

Virtual reality method to analyze visual recognition in mice.

PubMed

Young, Brent Kevin; Brennan, Jayden Nicole; Wang, Ping; Tian, Ning

2018-01-01

Behavioral tests have been extensively used to measure the visual function of mice. To determine how precisely mice perceive certain visual cues, it is necessary to have a quantifiable measurement of their behavioral responses. Recently, virtual reality tests have been utilized for a variety of purposes, from analyzing hippocampal cell functionality to identifying visual acuity. Despite the widespread use of these tests, the training requirement for the recognition of a variety of different visual targets, and the performance of the behavioral tests has not been thoroughly characterized. We have developed a virtual reality behavior testing approach that can essay a variety of different aspects of visual perception, including color/luminance and motion detection. When tested for the ability to detect a color/luminance target or a moving target, mice were able to discern the designated target after 9 days of continuous training. However, the quality of their performance is significantly affected by the complexity of the visual target, and their ability to navigate on a spherical treadmill. Importantly, mice retained memory of their visual recognition for at least three weeks after the end of their behavioral training.

Factors associated with fear of falling in community-dwelling older adults with and without diabetes mellitus: Findings from the Frailty in Brazilian Older People Study (FIBRA-BR).

PubMed

Moreira, Bruno de Souza; Sampaio, Rosana Ferreira; Diz, Juliano Bergamaschine Mata; Bastone, Alessandra de Carvalho; Ferriolli, Eduardo; Neri, Anita Liberalesso; Lourenço, Roberto Alves; Dias, Rosângela Corrêa; Kirkwood, Renata Noce

2017-03-01

This study aimed to investigate the associated factors with fear of falling in community-dwelling older adults with and without diabetes mellitus. Data from the Frailty in Brazilian Older People Study (FIBRA-BR), involving 4449 individuals aged 65years or older (19.2% with diabetes), were analyzed. The potential factors associated with fear of falling included sociodemographic data, chronic diseases, health-related variables and functional capacity measures. Logistic regression analysis was performed to identify the factors associated with fear of falling. Female gender, arthritis or rheumatism, negative health self-perception, frailty, lower Lawton Scale score and reduced gait speed were independently associated with fear of falling in both groups. Factors associated with fear of falling specific to non-diabetic older adults were depression, visual impairment, falls in the previous 12months, obesity, depressive symptoms, higher Katz Index score and decreased handgrip strength. Lower Mini-Mental State Examination score was an associated factor with fear of falling only in those with diabetes. The factors associated with fear of falling did differ between non-diabetic and diabetic older adults. Health care professionals should consider such differences when planning their therapeutic approaches for a successful management of fear of falling in these older populations. Copyright © 2017 Elsevier Inc. All rights reserved.

Water Vapor Transport, June through November 2005 Movie

NASA Image and Video Library

2008-11-18

This visualization from the Atmospheric Infrared Sounder AIRS on NASA Aqua satellite shows variations in the three dimensional distribution of water vapor in the atmosphere during the summer and fall of 2005.

Assessment of Visual Reliance in Balance Control: An Inexpensive Extension of the Static Posturography.

PubMed

Púčik, Jozef; Šaling, Marián; Lukáč, Tomáš; Ondráček, Oldřich; Kucharík, Martin

2014-01-01

Ability of humans to maintain balance in an upright stance and during movement activities is one of the most natural skills affecting everyday life. This ability progressively deteriorates with increasing age, and balance impairment, often aggravated by age-related diseases, can result in falls that adversely impact the quality of life. Falls represent serious problems of health concern associated with aging. Many investigators, involved in different science disciplines such as medicine, engineering, psychology, and sport, have been attracted by a research of the human upright stance. In a clinical practice, stabilometry based on the force plate is the most widely available procedure used to evaluate the balance. In this paper, we have proposed a low-cost extension of the conventional stabilometry by the multimedia technology that allows identifying potentially disturbing effects of visual sensory information. Due to the proposed extension, a stabilometric assessment in terms of line integral of center of pressure (COP) during moving scene stimuli shows higher discrimination power between young healthy and elderly subjects with supposed stronger visual reliance.

Assessment of Visual Reliance in Balance Control: An Inexpensive Extension of the Static Posturography

PubMed Central

Púčik, Jozef; Šaling, Marián; Lukáč, Tomáš; Ondráček, Oldřich; Kucharík, Martin

2014-01-01

Ability of humans to maintain balance in an upright stance and during movement activities is one of the most natural skills affecting everyday life. This ability progressively deteriorates with increasing age, and balance impairment, often aggravated by age-related diseases, can result in falls that adversely impact the quality of life. Falls represent serious problems of health concern associated with aging. Many investigators, involved in different science disciplines such as medicine, engineering, psychology, and sport, have been attracted by a research of the human upright stance. In a clinical practice, stabilometry based on the force plate is the most widely available procedure used to evaluate the balance. In this paper, we have proposed a low-cost extension of the conventional stabilometry by the multimedia technology that allows identifying potentially disturbing effects of visual sensory information. Due to the proposed extension, a stabilometric assessment in terms of line integral of center of pressure (COP) during moving scene stimuli shows higher discrimination power between young healthy and elderly subjects with supposed stronger visual reliance. PMID:27006930

Falling Barometer--Failing Behavior.

ERIC Educational Resources Information Center

Scagliotta, Edward G.

1980-01-01

Observations of 127 boys with behavior problems (ages 9 to 13) were made to study the correlation between air pressure and adverse behavior in the Ss. Results showed that, with each change in barometric pressure, there was an obvious change in the Ss' behavior. (PHR)

Risks, consequences, and prevention of falls of older people in oral healthcare centers.

PubMed

de Baat, Cees; de Baat, Paul; Gerritsen, Anneloes E; Flohil, Karien A; van der Putten, Gert-Jan; van der Maarel-Wierink, Claar D

2017-03-01

One-third of community-dwelling people older than 65 years of age fall each year, and half of them fall at least twice a year. Older care home residents are approximately three times more likely to fall when compared to community-dwelling older people. Risk indicators for falls are related to the older people's body, environment, behavior, and activities. An important health risk indicator is (orthostatic or postprandial) hypotension, which may induce cerebral hypoperfusion. Although the majority of falls remain without major consequences, 10% to 25% of falls in care homes result in bodily trauma. Prevalent fall-related injuries are brain injury, lower extremity fracture including hip fracture and forearm/wrist fracture, facial fracture, humeral fracture, and rib/scapular fracture. As fall accidents by older people can have severe consequences, prevention of falls is of paramount importance. Healthcare providers, including oral healthcare providers, should inform older people on risks of falling and draw attention to potentially hazardous arrangements. © 2016 Special Care Dentistry Association and Wiley Periodicals, Inc.

Visual Behaviors and Adaptations Associated with Cortical and Ocular Impairment in Children.

ERIC Educational Resources Information Center

Jan, J. E.; Groenveld, M.

1993-01-01

This article shows the usefulness of understanding visual behaviors in the diagnosis of various types of visual impairments that are due to ocular and cortical disorders. Behaviors discussed include nystagmus, ocular motor dyspraxia, head position, close viewing, field loss adaptations, mannerisms, photophobia, and abnormal color perception. (JDD)

Vision drives accurate approach behavior during prey capture in laboratory mice

PubMed Central

Hoy, Jennifer L.; Yavorska, Iryna; Wehr, Michael; Niell, Cristopher M.

2016-01-01

Summary The ability to genetically identify and manipulate neural circuits in the mouse is rapidly advancing our understanding of visual processing in the mammalian brain [1,2]. However, studies investigating the circuitry that underlies complex ethologically-relevant visual behaviors in the mouse have been primarily restricted to fear responses [3–5]. Here, we show that a laboratory strain of mouse (Mus musculus, C57BL/6J) robustly pursues, captures and consumes live insect prey, and that vision is necessary for mice to perform the accurate orienting and approach behaviors leading to capture. Specifically, we differentially perturbed visual or auditory input in mice and determined that visual input is required for accurate approach, allowing maintenance of bearing to within 11 degrees of the target on average during pursuit. While mice were able to capture prey without vision, the accuracy of their approaches and capture rate dramatically declined. To better explore the contribution of vision to this behavior, we developed a simple assay that isolated visual cues and simplified analysis of the visually guided approach. Together, our results demonstrate that laboratory mice are capable of exhibiting dynamic and accurate visually-guided approach behaviors, and provide a means to estimate the visual features that drive behavior within an ethological context. PMID:27773567

Reduced sensitivity for visual textures affects judgments of shape-from-shading and step-climbing behaviour in older adults.

PubMed

Schofield, Andrew J; Curzon-Jones, Benjamin; Hollands, Mark A

2017-02-01

Falls on stairs are a major hazard for older adults. Visual decline in normal ageing can affect step-climbing ability, altering gait and reducing toe clearance. Here we show that a loss of fine-grained visual information associated with age can affect the perception of surface undulations in patterned surfaces. We go on to show that such cues affect the limb trajectories of young adults, but due to their lack of sensitivity, not that of older adults. Interestingly neither the perceived height of a step nor conscious awareness is altered by our visual manipulation, but stepping behaviour is, suggesting that the influence of shape perception on stepping behaviour is via the unconscious, action-centred, dorsal visual pathway.

Understanding Design Vulnerabilities in the Physical Environment Relating to Patient Fall Patterns in a Psychiatric Hospital: Seven Years of Sentinel Events.

PubMed

Bayramzadeh, Sara; Portillo, Margaret; Carmel-Gilfilen, Candy

2018-05-01

The influence of the physical environment on patient falls has not been fully explored in psychiatric units, despite this patient population's vulnerability and the critical role of the physical environment in patient safety. The research objective is to describe the spatial and temporal pattern of falls occurrences and their location in relation to the levels of safety continuum model. This article presents an exploratory case study design. Seven years of retrospective data on patient falls, yielding 818 sentinel events, in an 81-bed psychiatric hospital in the United States were collected and analyzed. Data focused on extrinsic factors for falls, emphasizing the physical environment. Through a content analysis of the sentinel event narratives, recorded by the hospital staff, this study explored patient falls related to location and elements of the physical environment. The analysis revealed that 15% of recorded falls were attributed to some aspect of or element within the physical environment. The most typical locations of falls were patient rooms (39%), patient bathrooms (22%), and dayrooms (20%). Also, the results identified patterns of environmental factors that appeared linked to increasing patients' susceptibility to falls. Risk factors included poor nighttime lighting, flooring surfaces that were uneven, and spaces that inadvertently limited visual access and supervision. The physical environment plays an often-unexamined role in fall events and specific locations. These results are deserving of further research on design strategies and applications to reduce patient falls in psychiatric hospital settings.

Why do things fall? How to explain why gravity is not a force

NASA Astrophysics Data System (ADS)

Stannard, Warren B.

2018-03-01

In most high school physics classes, gravity is described as an attractive force between two masses as formulated by Newton over 300 years ago. Einstein’s general theory of relativity implies that gravitational effects are instead the result of a ‘curvature’ of space-time. However, explaining why things fall without resorting to Newton’s gravitational force can be difficult. This paper introduces some simple graphical and visual analogies and models which are suitable for the introduction of Einstein’s theory of general relativity at a high school level. These models provide an alternative to Newton’s gravitational force and help answer the simple question: why do things fall?

Figure-ground activity in primary visual cortex (V1) of the monkey matches the speed of behavioral response.

PubMed

Supèr, Hans; Spekreijse, Henk; Lamme, Victor A F

2003-06-26

To look at an object its position in the visual scene has to be localized and subsequently appropriate oculo-motor behavior needs to be initiated. This kind of behavior is largely controlled by the cortical executive system, such as the frontal eye field. In this report, we analyzed neural activity in the visual cortex in relation to oculo-motor behavior. We show that in a figure-ground detection task, the strength of late modulated activity in the primary visual cortex correlates with the saccade latency. We propose that this may indicate that the variability of reaction times in the detection of a visual stimulus is reflected in low-level visual areas as well as in high-level areas.

Teacher practices as predictors of children's classroom social preference.

PubMed

Mikami, Amori Yee; Griggs, Marissa Swaim; Reuland, Meg M; Gregory, Anne

2012-02-01

Students who do not get along with their peers are at elevated risk for academic disengagement and school failure. Research has predominantly focused on factors within such children that contribute to their peer problems. This study considers whether teacher practices also predict social preference for children in that classroom. Participants were 26 elementary school teachers and 490 students in their classrooms followed for one school year. Results suggested that teachers who favored the most academically talented students in the fall had classrooms where children had lower average social preference in the spring after statistical control of children's fall social preference and externalizing behavior problems. Teachers who demonstrated emotionally supportive relationships with students in the fall had classrooms where children had greater possibility of changing their social preference from fall to spring. Although children with high externalizing behaviors tended to experience declining social preference over the course of the school year, teachers' learner-centered practices attenuated this progression. However, teachers' favoring of the most academically talented accentuated the negative relation between externalizing behaviors and social preference. Implications for school psychology practitioners are discussed. Copyright © 2011 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Imbalance: Objective measures versus subjective self-report in clinical practice.

PubMed

Chiarovano, Elodie; Wang, Wei; Reynolds, Pam; MacDougall, Hamish G

2018-01-01

Dizziness and imbalance are very common complaints in clinical practice. One of the challenges is to evaluate the 'real' risk of falls. Two tools are available: the patient's self-report and the measure of the patient's balance. We evaluated the relationship between these methods using the Dizziness Handicap Inventory (DHI) and measures of balance while visual inputs are perturbed with Virtual Reality (VR). 90 consecutive patients underwent the DHI questionnaire and the balance test. The DHI questionnaire was used to measure the subject's perception of handicap associated with dizziness. The balance test measured the postural sway in several visual conditions: eyes open, eyes closed, and with an unpredictable visual perturbation using VR at several amplitudes of movement. No correlation was found between the DHI score and the balance measurement. The visual perturbations allow us to characterize patients into three groups: one group with a high DHI score who did not fall on the balance test (5.5%), one group with a low DHI score who failed eyes closed on a compliant surface (9.0%), and one group of the remaining patients (85.5%). The correlation between the DHI score and the balance performance became significant on the remaining group of patients. Both subjective self-report and objective measure are important to characterize a patient. The use of VR visual perturbations allowed us to define three important groups of patients. VR visual perturbations provided additional information that helps explain the lack of correlation between DHI and objective test results. Copyright © 2017 Elsevier B.V. All rights reserved.

Statistical data mining of streaming motion data for fall detection in assistive environments.

PubMed

Tasoulis, S K; Doukas, C N; Maglogiannis, I; Plagianakos, V P

2011-01-01

The analysis of human motion data is interesting for the purpose of activity recognition or emergency event detection, especially in the case of elderly or disabled people living independently in their homes. Several techniques have been proposed for identifying such distress situations using either motion, audio or video sensors on the monitored subject (wearable sensors) or the surrounding environment. The output of such sensors is data streams that require real time recognition, especially in emergency situations, thus traditional classification approaches may not be applicable for immediate alarm triggering or fall prevention. This paper presents a statistical mining methodology that may be used for the specific problem of real time fall detection. Visual data captured from the user's environment, using overhead cameras along with motion data are collected from accelerometers on the subject's body and are fed to the fall detection system. The paper includes the details of the stream data mining methodology incorporated in the system along with an initial evaluation of the achieved accuracy in detecting falls.

Practical example of the infrastructure protection against rock fall

NASA Astrophysics Data System (ADS)

Jirásko, Daniel; Vaníček, Ivan

2017-09-01

The protection of transport infrastructures against rock falls represents for the Czech Republic one of the sensitive questions. Rock falls, similarly as other typical geo-hazards for the Czech Republic, as landslides and floods, can have negative impact on safety and security of these infrastructures. One practical example how to reduce risk of rock fall is described in the paper. Great care is devoted to the visual inspection enabling to indicate places with high potential to failure. With the help of numerical modelling the range of rock fall negative impact is estimated. Protection measures are dealing with two basic ways. The first one utilize the results of numerical modelling for the optimal design of protection measures and the second one is focused on the monitoring of the rock blocks with high potential of instability together with wire-less transfer of measured results. After quick evaluation, e.g. comparison with warning values, some protection measures, mostly connected with closure of the potential sector, can be recommended.

Caregiver Cognition and Behavior in Day-Care Classrooms.

ERIC Educational Resources Information Center

Holloway, Susan D.

A study examined the relationship between change in daycare children's classroom behavior and the teacher's socialization behavior. Various behaviors of 69 children in 24 classrooms were observed and coded in the fall and spring of the school year. Observers coded teacher behavior according to the Caregiver Interaction Scale, which assesses…

Evaluation of an osteoporosis and fall risk intervention program for community-dwelling elderly. A quasi-experimental study of behavioral modifications.

PubMed

Grahn Kronhed, Ann-Charlotte; Blomberg, Carina; Löfman, Owe; Timpka, Toomas; Möller, Margareta

2006-06-01

Osteoporosis and fall fractures are increasing problems amongst the elderly. The aim of this study was to explore whether combined population-based and individual interventions directed at risk factors for osteoporosis and falls result in behavioral changes in an elderly population. A quasi-experimental design was used for the study. Persons aged >or=65 years were randomly selected in the intervention and control community. An intervention program was managed from the primary health care center and delivered to the community. Health education was designed to increase awareness of risk factors for the development of osteoporosis and falling. Questionnaires about lifestyle, health, previous fractures, safety behavior and physical activity level were distributed at baseline in 1989 and at the follow-ups in 1992 and 1994 in both communities. There was a difference of 17.7% between the dual intervention (receiving both population-based and individual interventions) and the control samples regarding the self-reported use of shoe/cane spikes, and a difference of 20.5% regarding the reported "moderate level" of physical activity in 1994. There was an increase in the number of participants in the dual intervention sample who, at baseline, had not reported equipping their homes with non-slip mats and removing loose rugs but who did report these changes in 1994. The increase in the reported use of shoe/cane spikes in the dual intervention sample was observed mainly for the period 1992-1994. A public health intervention model, including both population-based and individual interventions, can contribute to behavioral changes in the prevention of falls and changed physical activity patterns amongst elderly people.

Using Eye Tracking to Explore Consumers' Visual Behavior According to Their Shopping Motivation in Mobile Environments.

PubMed

Hwang, Yoon Min; Lee, Kun Chang

2017-07-01

Despite a strong shift to mobile shopping trends, many in-depth questions about mobile shoppers' visual behaviors in mobile shopping environments remain unaddressed. This study aims to answer two challenging research questions (RQs): (a) how much does shopping motivation like goal orientation and recreation influence mobile shoppers' visual behavior toward displays of shopping information on a mobile shopping screen and (b) how much of mobile shoppers' visual behavior influences their purchase intention for the products displayed on a mobile shopping screen? An eye-tracking approach is adopted to answer the RQs empirically. The experimental results showed that goal-oriented shoppers paid closer attention to products' information areas to meet their shopping goals. Their purchase intention was positively influenced by their visual attention to the two areas of interest such as product information and consumer opinions. In contrast, recreational shoppers tended to visually fixate on the promotion area, which positively influences their purchase intention. The results contribute to understanding mobile shoppers' visual behaviors and shopping intentions from the perspective of mindset theory.

Person-Centered Fall Risk Awareness Perspectives: Clinical Correlates and Fall Risk.

PubMed

Verghese, Joe

2016-12-01

To identify clinical correlates of person-centered fall risk awareness and their validity for predicting falls. Prospective cohort study. Community. Ambulatory community-dwelling older adults without dementia (N = 316; mean age 78, 55% female). Fall risk awareness was assessed using a two-item questionnaire that asked participants about overall likelihood of someone in their age group having a fall and their own personal risk of falling over the next 12 months. Incident falls were recorded over study follow-up. Fifty-three participants (16.8%) responded positively to the first fall risk awareness question about being likely to have a fall in the next 12 months, and 100 (31.6%) reported being at personal risk of falling over the next 12 months. There was only fair correlation (κ = 0.370) between responses on the two questions. Prior falls and depressive symptoms were associated with positive responses on both fall risk awareness questions. Age and other established fall risk factors were not associated with responses on either fall risk awareness question. The fall risk awareness questionnaire did not predict incident falls or injurious falls. Fall risk awareness is low in older adults. Although person-centered fall risk awareness is not predictive of falls, subjective risk perceptions should be considered when designing fall preventive strategies because they may influence participation and behaviors. © 2016, Copyright the Author Journal compilation © 2016, The American Geriatrics Society.

Diel behavior of rearing fall Chinook salmon

USGS Publications Warehouse

Tiffan, Kenneth F.; Kock, Tobias J.; Skalicky, Joseph J.

2010-01-01

In fisheries science, habitat use is often inferred when fish are sampled or observed in a particular location. Physical habitat is typically measured where fish are found, and thus deemed important to habitat use. Although less common, a more informative approach is to measure or observe fish behavior within given habitats to more thoroughly assess their use of those locations. While this approach better reflects how fish use habitat, fish behavior can be difficult to quantify, particularly at night. For example, Tiffan and others (2002, 2006) were able to quantify habitat availability and characteristics that were important for rearing juvenile fall Chinook Salmon (Oncorhynchus tshawytscha) in the Hanford Reach of the Columbia River. The authors, however, could only speculate as to how juvenile salmon use habitat and respond to changes in water level fluctuations. Conversely, in this study we provide data on the diel activities of rearing juvenile wild fall Chinook Salmon which provides a better understanding of how fish “use” these rearing habitats. Diel behavior patterns are important because fish in the Hanford Reach are often stranded on shorelines when the water level rapidly recedes because of hydroelectric power generation at upriver dams (Nugent and others 2002; Anglin and others 2006). We hypothesize that juvenile salmon are at greater risk of stranding at night because they are less active and occupy habitat differently than during the day. We used underwater videography to collect behavioral information during the day and night to determine if juvenile fall Chinook Salmon are more susceptible to stranding when water level fluctuations occur at night.

Increased Complexities in Visual Search Behavior in Skilled Players for a Self-Paced Aiming Task

PubMed Central

Chia, Jingyi S.; Burns, Stephen F.; Barrett, Laura A.; Chow, Jia Y.

2017-01-01

The badminton serve is an important shot for winning a rally in a match. It combines good technique with the ability to accurately integrate visual information from the shuttle, racket, opponent, and intended landing point. Despite its importance and repercussive nature, to date no study has looked at the visual search behaviors during badminton service in the singles discipline. Unlike anticipatory tasks (e.g., shot returns), the serve presents an opportunity to explore the role of visual search behaviors in movement control for self-paced tasks. Accordingly, this study examined skill-related differences in visual behavior during the badminton singles serve. Skilled (n = 12) and less skilled (n = 12) participants performed 30 serves to a live opponent, while real-time eye movements were captured using a mobile gaze registration system. Frame-by-frame analyses of 662 serves were made and the skilled players took a longer preparatory time before serving. Visual behavior of the skilled players was characterized by significantly greater number of fixations on more areas of interest per trial than the less skilled. In addition, the skilled players spent a significantly longer time fixating on the court and net, whereas the less skilled players found the shuttle to be more informative. Quiet eye (QE) duration (indicative of superior sports performance) however, did not differ significantly between groups which has implications on the perceived importance of QE in the badminton serve. Moreover, while visual behavior differed by skill level, considerable individual differences were also observed especially within the skilled players. This augments the need for not just group-level analyses, but individualized analysis for a more accurate representation of visual behavior. Findings from this study thus provide an insight to the possible visual search strategies as players serve in net-barrier games. Moreover, this study highlighted an important aspect of badminton relating to deception and the implications of interpreting visual behavior of players. PMID:28659850

Increased Complexities in Visual Search Behavior in Skilled Players for a Self-Paced Aiming Task.

PubMed

Chia, Jingyi S; Burns, Stephen F; Barrett, Laura A; Chow, Jia Y

2017-01-01

The badminton serve is an important shot for winning a rally in a match. It combines good technique with the ability to accurately integrate visual information from the shuttle, racket, opponent, and intended landing point. Despite its importance and repercussive nature, to date no study has looked at the visual search behaviors during badminton service in the singles discipline. Unlike anticipatory tasks (e.g., shot returns), the serve presents an opportunity to explore the role of visual search behaviors in movement control for self-paced tasks. Accordingly, this study examined skill-related differences in visual behavior during the badminton singles serve. Skilled ( n = 12) and less skilled ( n = 12) participants performed 30 serves to a live opponent, while real-time eye movements were captured using a mobile gaze registration system. Frame-by-frame analyses of 662 serves were made and the skilled players took a longer preparatory time before serving. Visual behavior of the skilled players was characterized by significantly greater number of fixations on more areas of interest per trial than the less skilled. In addition, the skilled players spent a significantly longer time fixating on the court and net, whereas the less skilled players found the shuttle to be more informative. Quiet eye (QE) duration (indicative of superior sports performance) however, did not differ significantly between groups which has implications on the perceived importance of QE in the badminton serve. Moreover, while visual behavior differed by skill level, considerable individual differences were also observed especially within the skilled players. This augments the need for not just group-level analyses, but individualized analysis for a more accurate representation of visual behavior. Findings from this study thus provide an insight to the possible visual search strategies as players serve in net-barrier games. Moreover, this study highlighted an important aspect of badminton relating to deception and the implications of interpreting visual behavior of players.

Anomalous behaviors of Wyrtki Jets in the equatorial Indian Ocean during 2013

PubMed Central

Duan, Yongliang; Liu, Lin; Han, Guoqing; Liu, Hongwei; Yu, Weidong; Yang, Guang; Wang, Huiwu; Wang, Haiyuan; Liu, Yanliang; Zahid; Waheed, Hussain

2016-01-01

In-situ measurement of the upper ocean velocity discloses significant abnormal behaviors of two Wyrtki Jets (WJs) respectively in boreal spring and fall, over the tropical Indian Ocean in 2013. The two WJs both occurred within upper 130 m depth and persisted more than one month. The exceptional spring jet in May was unusually stronger than its counterpart in fall, which is clearly against the previous understanding. Furthermore, the fall WJ in 2013 unexpectedly peaked in December, one month later than its climatology. Data analysis and numerical experiments illustrate that the anomalous changes in the equatorial zonal wind, associated with the strong intra-seasonal oscillation events, are most likely the primary reason for such anomalous WJs activities. PMID:27436723

Utricular hypofunction in patients with type 2 diabetes mellitus.

PubMed

Jáuregui-Renaud, K; Aranda-Moreno, C; Herrera-Rangel, A

2017-10-01

The aim of this study was to assess the function of the utricle and horizontal semicircular canals in patients with type 2 diabetes mellitus receiving primary health care, with/without a history of falls. 101 patients with type 2 diabetes mellitus, 34 to 84 years old (26 with and 75 without a history of falls) and 51 healthy volunteers (40-83 years old) accepted to participate. They denied having a history of dizziness, vertigo, unsteadiness, hearing loss, or neurological disorders. None of them were seeking care due to sensory or balance decline. After a clinical evaluation and report of symptoms related to balance using a standardised questionnaire, lateral canal function was assessed by sinusoidal rotation at 0.16 Hz and 1.28 Hz (60°/sec peak velocity), otolith function was assessed by static visual vertical (average of 10 trials) and dynamic visual vertical during unilateral centrifugation (300°/sec at 3.5 cm) and static posturography was performed on hard/ soft surface with eyes open/closed. Compared to healthy volunteers, patients showed decreased responses to unilateral centrifugation, but similar responses to horizontal canal stimuli (independently of age, peripheral neuropathy or a history of falls) (ANCoVA p < 0.05) and a larger sway area with a lengthier sway path. Compared to patients with no falls, patients with falls had a higher female/male ratio and a higher frequency of score ≥ 4 on the questionnaire of symptoms related to balance, but similar age, body mass index and frequency of peripheral neuropathy. In patients with type 2 diabetes mellitus, receiving primary healthcare who are not seeking care due to sensory or balance decline, utricular function may be impaired even in the absence of horizontal canal dysfunction or a history of falls. © Copyright by Società Italiana di Otorinolaringologia e Chirurgia Cervico-Facciale, Rome, Italy.

An Application of Project-Based Learning in an Urban Project Topic in the Visual Arts Course in 8th Classes of Primary Education

ERIC Educational Resources Information Center

Kalyoncu, Raif; Tepecik, Adnan

2010-01-01

The purpose of this study is to measure the effect of project-based learning that is used in visual arts course on students' academic success and permanence. The research was applied to students of Hasan Ali Yucel Primary School in the city of Trabzon during the fall semester of 2007-2008 academic year. Among the sample that had been selected…

Examination of associations between risky driving behaviors and hazardous drinking among a sample of college students.

PubMed

Martin, Ryan J; Cox, Melissa J; Chaney, Beth H; Knowlden, Adam P

2018-06-21

Hazardous drinking is associated with other risky behaviors and negative health-related outcomes. This study examined co-variation between hazardous drinking scores and the following risky driving behaviors: falling asleep while driving, texting (receiving and sending) while driving, and driving after consuming alcohol. The participants in this study were a sample of undergraduate students (N = 1,298) who were enrolled in an introductory health course at a large, Southeastern university in Spring 2016 and completed an online health survey that assessed hazardous drinking, falling asleep while driving, texting while driving, and driving after consuming alcohol. We conducted a series of two-step regression analyses to examine co-variation between hazardous drinking scores (using the AUDIT-C) and the risky driving behaviors of interest. We found that the majority of participants did not drink and drive (91.8%) nor did they fall asleep while driving (80.4%); however, the majority did read a text while driving (81.7%) and sent a text while driving (75.3%). In the full multivariable model, hazardous drinking score was positively associated with drinking and driving (Step 2 OR = 1.28, 95% CI: 1.18, 1.38) and sending a text message while driving (Step 2 b = 0.19, p = .01). Hazardous drinking score was also positively associated with reading a text while driving (Step 1 b = 0.14, p<.001) and falling asleep while driving (Step 1 b = 0.02, p=.02) in the model only controlling for demographic characteristics. The analyses also indicated co-variability between the following risky driving behaviors: (1) drinking and driving/reading a text message while driving, (2) drinking and driving/falling asleep and driving, (3) reading a text while driving/sending a text while driving, and (4) sending a text while driving/sleeping and driving. The findings of this study indicate a need for interventions discouraging both hazardous drinking and risky driving behaviors in college student populations; recommendations to reduce risky driving and hazardous drinking are discussed.

Smartphone serious games for vision and hearing assessment.

PubMed

Dias, Pedro; Aguiar, Bruno; Sousa, Filipe; Sousa, Augusto

2015-01-01

Falls are the second leading cause of accidental injury deaths worldwide. In this paper, it is intended to define methodologies that permit the evaluation of two potential factors which might have an impact on fall risk, these are: visual and hearing loss. The aim of the work developed is not to replace clinic visits, but to offer the user the means to continue the tracking of his vision and hearing at home, during the long time intervals between clinical tests. Tests conducted in a sample of our target users indicate a good ability to measure vision and hearing using an android smartphone and the proposed methodologies. While some tests require further validation, promising results were achieved in the most common tests for vision and hearing, presenting a good correlation between the system's results when compared to the traditional tests (for distance visual acuity) and the data gathered from the users (for hearing tests).

Balance control and anti‐gravity muscle activity during the experience of fear at heights

PubMed Central

Wuehr, Max; Kugler, Guenter; Schniepp, Roman; Eckl, Maria; Pradhan, Cauchy; Jahn, Klaus; Huppert, Doreen; Brandt, Thomas

2014-01-01

Abstract Fear of heights occurs when a visual stimulus causes the apprehension of losing balance and falling. A moderate form of visual height intolerance (vHI) affects about one third of the general population and has relevant consequences for the quality of life. A quantitative evaluation of balance mechanisms in persons susceptible to vHI during height exposure is missing. VHI‐related changes in postural control were assessed by center‐of‐pressure displacements and electromyographic recordings of selected leg, arm, and neck muscles in 16 subjects with vHI while standing at heights on an emergency balcony versus standing in the laboratory at ground level. Characteristics of open‐ and closed‐loop postural control were analyzed. Body sway and muscle activity parameters were correlated with the subjective estimates of fear at heights. During height exposure, (1) open‐loop control was disturbed by a higher diffusion activity (P < 0.001) and (2) the sensory feedback threshold for closed‐loop control was lowered (P < 0.010). Altered postural control was predominantly associated with increased co‐contraction of leg muscles. Body sway and leg and neck muscle co‐contraction correlated with the severity of subjective anxiety (P < 0.050). Alterations in postural control diminished if there were nearby stationary contrasts in the visual surrounding or if subjects stood with eyes closed. The performance of a cognitive dual task also improved impaired balance. Visual heights have two behavioral effects in vHI subjects: A change occurs in (1) open‐ and closed‐loop postural control strategy and (2) co‐contraction of anti‐gravity leg and neck muscles, both of which depend on the severity of evoked fear at heights. PMID:24744901

Prevalence and correlates of hearing and visual impairments in European nursing homes: results from the SHELTER study.

PubMed

Yamada, Yukari; Vlachova, Martina; Richter, Tomas; Finne-Soveri, Harriet; Gindin, Jacob; van der Roest, Henriëtte; Denkinger, Michael D; Bernabei, Roberto; Onder, Graziano; Topinkova, Eva

2014-10-01

Visual and hearing impairments are known to be related to functional disability, cognitive impairment, and depression in community-dwelling older people. The aim of this study was to examine the prevalence of sensory impairment in nursing home residents, and whether sensory impairment is related to other common clinical problems in nursing homes, mediated by functional disability, cognitive impairment, and depressive symptoms. Cross-sectional data of 4007 nursing home residents in 59 facilities in 8 countries from the SHELTER study were analyzed. Visual and hearing impairments were assessed by trained staff using the interRAI instrument for Long-Term Care Facilities. Generalized linear mixed models adjusted for functional disability, cognitive impairment, and depressive symptoms were used to analyze associations of sensory impairments with prevalence of clinical problems, including behavioral symptoms, incontinence, fatigue, falls, problems with balance, sleep, nutrition, and communication. Of the participants, 32% had vision or hearing impairment (single impairment) and another 32% had both vision and hearing impairments (dual impairment). Residents with single impairment had significantly higher rates of communication problems, fatigue, balance problems, and sleep problems, as compared with residents without any sensory impairment. Those with dual impairment had significantly higher rates of all clinical problems assessed in this study as compared with those without sensory impairment. For each clinical problem, the magnitude of the odds ratio for specific clinical problems was higher for dual impairment than for single impairment. Visual and hearing impairments are associated with higher rates of common clinical problems among nursing home residents, independent of functional disability, cognitive impairment, and depressive symptoms. Copyright © 2014 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Balance control and anti-gravity muscle activity during the experience of fear at heights.

PubMed

Wuehr, Max; Kugler, Guenter; Schniepp, Roman; Eckl, Maria; Pradhan, Cauchy; Jahn, Klaus; Huppert, Doreen; Brandt, Thomas

2014-02-01

Fear of heights occurs when a visual stimulus causes the apprehension of losing balance and falling. A moderate form of visual height intolerance (vHI) affects about one third of the general population and has relevant consequences for the quality of life. A quantitative evaluation of balance mechanisms in persons susceptible to vHI during height exposure is missing. VHI-related changes in postural control were assessed by center-of-pressure displacements and electromyographic recordings of selected leg, arm, and neck muscles in 16 subjects with vHI while standing at heights on an emergency balcony versus standing in the laboratory at ground level. Characteristics of open- and closed-loop postural control were analyzed. Body sway and muscle activity parameters were correlated with the subjective estimates of fear at heights. During height exposure, (1) open-loop control was disturbed by a higher diffusion activity (P < 0.001) and (2) the sensory feedback threshold for closed-loop control was lowered (P < 0.010). Altered postural control was predominantly associated with increased co-contraction of leg muscles. Body sway and leg and neck muscle co-contraction correlated with the severity of subjective anxiety (P < 0.050). Alterations in postural control diminished if there were nearby stationary contrasts in the visual surrounding or if subjects stood with eyes closed. The performance of a cognitive dual task also improved impaired balance. Visual heights have two behavioral effects in vHI subjects: A change occurs in (1) open- and closed-loop postural control strategy and (2) co-contraction of anti-gravity leg and neck muscles, both of which depend on the severity of evoked fear at heights.

Marked colour divergence in the gliding membranes of a tropical lizard mirrors population differences in the colour of falling leaves

PubMed Central

Klomp, D. A.; Stuart-Fox, D.; Das, I.; Ord, T. J.

2014-01-01

Populations of the Bornean gliding lizard, Draco cornutus, differ markedly in the colour of their gliding membranes. They also differ in local vegetation type (mangrove forest versus lowland rainforest) and consequently, the colour of falling leaves (red and brown/black in mangrove versus green, brown and black in rainforest). We show that the gliding membranes of these lizards closely match the colours of freshly fallen leaves in the local habitat as they appear to the visual system of birds (their probable predators). Furthermore, gliding membranes more closely resembled colours of local fallen leaves than standing foliage or fallen leaves in the other population's habitat. This suggests that the two populations have diverged in gliding membrane coloration to match the colours of their local falling leaves, and that mimicking falling leaves is an adaptation that functions to reduce predation by birds. PMID:25540157

Timing of Visual Bodily Behavior in Repair Sequences: Evidence from Three Languages

ERIC Educational Resources Information Center

Floyd, Simeon; Manrique, Elizabeth; Rossi, Giovanni; Torreira, Francisco

2016-01-01

This article expands the study of other-initiated repair in conversation--when one party signals a problem with producing or perceiving another's turn at talk--into the domain of visual bodily behavior. It presents one primary cross-linguistic finding about the timing of visual bodily behavior in repair sequences: if the party who initiates repair…

Zolpidem is independently associated with increased risk of inpatient falls.

PubMed

Kolla, Bhanu Prakash; Lovely, Jenna K; Mansukhani, Meghna P; Morgenthaler, Timothy I

2013-01-01

Inpatient falls are associated with significant morbidity and increased healthcare costs. Zolpidem has been reported to decrease balance and is associated with falls. Yet, it is a commonly used hypnotic agent in the inpatient setting. Zolpidem use in hospitalized patients may be a significant and potentially modifiable risk factor for falling. To determine whether inpatients administered zolpidem are at greater risk of falling. Retrospective cohort study. Adult non-intensive care unit (non-ICU) inpatients at a tertiary care center. Adult inpatients who were prescribed zolpidem were identified. Electronic medical records were reviewed to capture demographics and other risk factors for falls. The fall rate was compared in those administered zolpidem versus those only prescribed zolpidem. Multivariate analyses were performed to determine whether zolpidem was independently associated with falls. The fall rate among patients who were prescribed and received zolpidem (n = 4962) was significantly greater than among patients who were prescribed but did not receive zolpidem (n = 11,358) (3.04% vs 0.71%; P < 0.001). Zolpidem use continued to remain significantly associated with increased fall risk after accounting for age, gender, insomnia, delirium status, dose of zolpidem, Charlson comorbidity index, Hendrich's fall risk score, length of hospital stay, presence of visual impairment, gait abnormalities, and dementia/cognitive impairment (adjusted odds ratio [OR] 4.37, 95% confidence interval [CI] = 3.34-5.76; P < 0.001). Additionally, patients taking zolpidem who experienced a fall did not differ from other hospitalized adult patients who fell in terms of age, opioids, antidepressants, sedative-antidepressants, antipsychotics, benzodiazepine, or antihistamine use. Zolpidem use was a strong, independent, and potentially modifiable risk factor for inpatient falls. Copyright © 2012 Society of Hospital Medicine.

An individually-tailored multifactorial intervention program for older fallers in a middle-income developing country: Malaysian Falls Assessment and Intervention Trial (MyFAIT)

PubMed Central

2014-01-01

Background In line with a rapidly ageing global population, the rise in the frequency of falls will lead to increased healthcare and social care costs. This study will be one of the few randomized controlled trials evaluating a multifaceted falls intervention in a low-middle income, culturally-diverse older Asian community. The primary objective of our paper is to evaluate whether individually tailored multifactorial interventions will successfully reduce the number of falls among older adults. Methods Three hundred community-dwelling older Malaysian adults with a history of (i) two or more falls, or (ii) one injurious fall in the past 12 months will be recruited. Baseline assessment will include cardiovascular, frailty, fracture risk, psychological factors, gait and balance, activities of daily living and visual assessments. Fallers will be randomized into 2 groups: to receive tailored multifactorial interventions (intervention group); or given lifestyle advice with continued conventional care (control group). Multifactorial interventions will target 6 specific risk factors. All participants will be re-assessed after 12 months. The primary outcome measure will be fall recurrence, measured with monthly falls diaries. Secondary outcomes include falls risk factors; and psychological measures including fear of falling, and quality of life. Discussion Previous studies evaluating multifactorial interventions in falls have reported variable outcomes. Given likely cultural, personal, lifestyle and health service differences in Asian countries, it is vital that individually-tailored multifaceted interventions are evaluated in an Asian population to determine applicability of these interventions in our setting. If successful, these approaches have the potential for widespread application in geriatric healthcare services, will reduce the projected escalation of falls and fall-related injuries, and improve the quality of life of our older community. Trial registration ISRCTN11674947 PMID:24951180

Improvement of Physical Therapist Assessment of Risk of Falls in the Hospital and Discharge Handover Through an Intervention to Modify Clinical Behavior.

PubMed

Thomas, Susie; Mackintosh, Shylie

2016-06-01

Discharge from the hospital is a high risk transition period for older adults at risk of falls. Guidelines relevant to physical therapists for managing this risk are well documented, but commonly not implemented. This project implemented an intervention to improve physical therapists' adherence to key guideline recommendations for managing risk of falls on discharge from one hospital. A pretest-posttest study design was undertaken and was underpinned by the Theoretical Domains Framework (TDF) to aid in the design of interventions to increase physical therapists' adherence to guideline recommendations and to identify barriers to these interventions. A multifaceted intervention was implemented, including the establishment of a governance committee, education sessions, development of a "pathway" to guide practice, modification of an existing standardized assessment proforma, development of standardized processes and indicators for handover, increasing availability of educational handouts, audit and feedback processes, and allocation of dedicated staffing to oversee falls prevention within the physical therapy department. There were significant improvements in physical therapist behavior leading to key guideline recommendations being met, including: the proportion of patients who were identified to be at risk of falls (6.3% preintervention versus 94.8% postintervention) prior to discharge, an increase in documentation of clinical handover at discharge (68.6% preintervention versus 90.9% postintervention), and improvement in the quality of this documented clinical handover (34.9% of case notes met 5 criteria preintervention versus 92.9% postintervention). The approach was resource intensive and consequently may be difficult to replicate at other sites. A multifaceted intervention underpinned by the TDF, designed to modify physical therapists' behavior to improve adherence to guideline recommendations for managing risk of falls on discharge from one hospital, was successful. © 2016 American Physical Therapy Association.

Fall prevention and safety communication training for foremen:Report of a pilot project designed to improve residential construction safety

PubMed Central

Kaskutas, Vicki; Dale, Ann Marie; Lipscomb, Hester; Evanoff, Brad

2013-01-01

Problem Falls from heights account for 64% of residential construction worker fatalities and 20% of missed work days. We hypothesized that worker safety would improve with foremen training in fall prevention and safety communication. Method Training priorities identified through foreman and apprentice focus groups and surveys were integrated into an 8-hour training. We piloted the training with ten foremen employed by a residential builder. Carpenter trainers contrasted proper methods to protect workers from falls with methods observed at the foremen’s worksites. Trainers presented methods to deliver toolbox talks and safety messages. Results from worksite observational audits (n=29) and foremen/crewmember surveys (n=97) administered before and after training were compared. Results We found that inexperienced workers are exposed to many fall hazards that they are often not prepared to negotiate. Fall protection is used inconsistently and worksite mentorship is often inadequate. Foremen feel pressured to meet productivity demands and some are unsure of the fall protection requirements. After the training, the frequency of daily mentoring and toolbox talks increased, and these talks became more interactive and focused on hazardous daily work tasks. Foremen observed their worksites for fall hazards more often. We observed increased compliance with fall protection and decreased unsafe behaviors during worksite audits. Discussion Designing the training to meet both foremen’s and crewmembers’ needs ensured the training was learner-centered and contextually-relevant. This pilot suggests that training residential foremen can increase use of fall protection, improve safety behaviors, and enhance on-the-job training and safety communication at their worksites. Impact on Industry Construction workers’ training should target safety communication and mentoring skills with workers who will lead work crews. Interventions at multiple levels are necessary to increase safety compliance in residential construction and decrease falls from heights. PMID:23398712

Fall prevention and safety communication training for foremen: report of a pilot project designed to improve residential construction safety.

PubMed

Kaskutas, Vicki; Dale, Ann Marie; Lipscomb, Hester; Evanoff, Brad

2013-02-01

Falls from heights account for 64% of residential construction worker fatalities and 20% of missed work days. We hypothesized that worker safety would improve with foremen training in fall prevention and safety communication. Training priorities identified through foreman and apprentice focus groups and surveys were integrated into an 8-hour training. We piloted the training with ten foremen employed by a residential builder. Carpenter trainers contrasted proper methods to protect workers from falls with methods observed at the foremen's worksites. Trainers presented methods to deliver toolbox talks and safety messages. Results from worksite observational audits (n=29) and foremen/crewmember surveys (n=97) administered before and after training were compared. We found that inexperienced workers are exposed to many fall hazards that they are often not prepared to negotiate. Fall protection is used inconsistently and worksite mentorship is often inadequate. Foremen feel pressured to meet productivity demands and some are unsure of the fall protection requirements. After the training, the frequency of daily mentoring and toolbox talks increased, and these talks became more interactive and focused on hazardous daily work tasks. Foremen observed their worksites for fall hazards more often. We observed increased compliance with fall protection and decreased unsafe behaviors during worksite audits. Designing the training to meet both foremen's and crewmembers' needs ensured the training was learner-centered and contextually-relevant. This pilot suggests that training residential foremen can increase use of fall protection, improve safety behaviors, and enhance on-the-job training and safety communication at their worksites. Construction workers' training should target safety communication and mentoring skills with workers who will lead work crews. Interventions at multiple levels are necessary to increase safety compliance in residential construction and decrease falls from heights. Copyright © 2013 Elsevier Ltd. All rights reserved.

Data Visualization and Storytelling: Students Showcasing Innovative Work on the NASA Hyperwall

NASA Astrophysics Data System (ADS)

Hankin, E. R.; Hasan, M.; Williams, B. M.; Harwell, D. E.

2017-12-01

Visual storytelling can be used to quickly and effectively tell a story about data and scientific research, with powerful visuals driving a deeper level of engagement. In 2016, the American Geophysical Union (AGU) launched a pilot contest with a grant from NASA to fund students to travel to the AGU Fall Meeting to present innovative data visualizations with fascinating stories on the NASA Hyperwall. This presentation will discuss the purpose of the contest and provide highlights. Additionally, the presentation will feature Mejs Hasan, one of the 2016 contest grand prize winners, who will discuss her award-winning research utilizing Landsat visual data, MODIS Enhanced Vegetation Index data, and NOAA nightlight data to study the effects of both drought and war on the Middle East.

Behavior Analysis Based on Coordinates of Body Tags

NASA Astrophysics Data System (ADS)

Luštrek, Mitja; Kaluža, Boštjan; Dovgan, Erik; Pogorelc, Bogdan; Gams, Matjaž

This paper describes fall detection, activity recognition and the detection of anomalous gait in the Confidence project. The project aims to prolong the independence of the elderly by detecting falls and other types of behavior indicating a health problem. The behavior will be analyzed based on the coordinates of tags worn on the body. The coordinates will be detected with radio sensors. We describe two Confidence modules. The first one classifies the user's activity into one of six classes, including falling. The second one detects walking anomalies, such as limping, dizziness and hemiplegia. The walking analysis can automatically adapt to each person by using only the examples of normal walking of that person. Both modules employ machine learning: the paper focuses on the features they use and the effect of tag placement and sensor noise on the classification accuracy. Four tags were enough for activity recognition accuracy of over 93% at moderate sensor noise, while six were needed to detect walking anomalies with the accuracy of over 90%.

Patient centered fall risk awareness perspectives: clinical correlates and fall risk

PubMed Central

Verghese, Joe

2016-01-01

Background While objective measures to assess risk of falls in older adults have been established; the value of patient self-reports in the context of falls is not known. Objectives To identify clinical correlates of patient centered fall risk awareness, and their validity for predicting falls. Design Prospective cohort study. Setting and Participants 316 non-demented and ambulatory community-dwelling older adults (mean age 78 years, 55% women). Measurements Fall risk awareness was assessed with a two-item questionnaire, which asked participants about overall likelihood and personal risk of falling over the next 12 months. Incident falls were recorded over study follow-up. Results Fifty-three participants (16.8%) responded positively to the first fall risk awareness question about being likely to have a fall in the next 12 months, and 100 (31.6%) reported being at personal risk of falling over the next 12 months. There was only fair correlation (kappa 0.370) between responses on the two questions. Prior falls and depressive symptoms were associated with positive responses on both fall risk awareness questions. Age and other established fall risk factors were not associated with responses on both fall risk awareness questions. The fall risk awareness questionnaire did not predict incident falls or injurious falls. Conclusion Fall risk awareness is low in older adults. While patient centered fall risk awareness is not predictive of falls, subjective risk perceptions should be considered when designing fall preventive strategies as they may influence participation and behaviors. PMID:27801936

Falls in patients with chronic obstructive pulmonary disease: a call for further research

PubMed Central

Roig, M; Eng, JJ; MacIntyre, DL; Road, JD; Reid, WD.

2012-01-01

Summary Chronic obstructive pulmonary disease (COPD) is a respiratory disease that results in airflow limitation and respiratory distress. The effects of COPD, however, are not exclusively limited to respiratory function and people with COPD face many non-respiratory manifestations that affect both function and mobility. Deficits in function and mobility have been associated with an increased risk for falling in older adults. The purpose of this study was to provide a theoretical framework to identify risks factors for falls in people with COPD. We have analyzed the literature to identify possible relationships between pathophysiological changes observed in COPD and common risk factors for falls. Well-established fall risk factors in people with COPD include lower limb muscle weakness and impaired activities of daily living. Other intrinsic risk factors such as gait and balance deficits, nutritional depletion, malnutrition, depression, cognitive impairments and medications are possible risk factors that need to be confirmed with more studies. There is no evidence that visual deficits are common in COPD. The role that precipitating factors such as syncope and postural hypotension may have on fall risk is unclear. Exacerbations and dyspnea do not have a precipitating effect on fall risk but they contribute to the progressive physical deterioration that may theoretically increase the risk for falls. While these results suggest that people with COPD might have an increased susceptibility to fall compared to their healthy peers, further research is needed to determine the prevalence of falls and specific risk factors for falls in people living with COPD. PMID:19419852

Searching for the right word: Hybrid visual and memory search for words.

PubMed

Boettcher, Sage E P; Wolfe, Jeremy M

2015-05-01

In "hybrid search" (Wolfe Psychological Science, 23(7), 698-703, 2012), observers search through visual space for any of multiple targets held in memory. With photorealistic objects as the stimuli, response times (RTs) increase linearly with the visual set size and logarithmically with the memory set size, even when over 100 items are committed to memory. It is well-established that pictures of objects are particularly easy to memorize (Brady, Konkle, Alvarez, & Oliva Proceedings of the National Academy of Sciences, 105, 14325-14329, 2008). Would hybrid-search performance be similar if the targets were words or phrases, in which word order can be important, so that the processes of memorization might be different? In Experiment 1, observers memorized 2, 4, 8, or 16 words in four different blocks. After passing a memory test, confirming their memorization of the list, the observers searched for these words in visual displays containing two to 16 words. Replicating Wolfe (Psychological Science, 23(7), 698-703, 2012), the RTs increased linearly with the visual set size and logarithmically with the length of the word list. The word lists of Experiment 1 were random. In Experiment 2, words were drawn from phrases that observers reported knowing by heart (e.g., "London Bridge is falling down"). Observers were asked to provide four phrases, ranging in length from two words to no less than 20 words (range 21-86). All words longer than two characters from the phrase, constituted the target list. Distractor words were matched for length and frequency. Even with these strongly ordered lists, the results again replicated the curvilinear function of memory set size seen in hybrid search. One might expect to find serial position effects, perhaps reducing the RTs for the first (primacy) and/or the last (recency) members of a list (Atkinson & Shiffrin, 1968; Murdock Journal of Experimental Psychology, 64, 482-488, 1962). Surprisingly, we showed no reliable effects of word order. Thus, in "London Bridge is falling down," "London" and "down" were found no faster than "falling."

Influence of the visual environment on the postural stability in healthy older women.

PubMed

Brooke-Wavell, K; Perrett, L K; Howarth, P A; Haslam, R A

2002-01-01

A poor postural stability in older people is associated with an increased risk of falling. It is recognized that visual environment factors (such as poor lighting and repeating patterns on escalators) may contribute to falls, but little is known about the effects of the visual environment on postural stability in the elderly. To determine whether the postural stability of older women (using body sway as a measure) differed under five different visual environment conditions. Subjects were 33 healthy women aged 65-76 years. Body sway was measured using an electronic force platform which identified the location of their centre of gravity every 0.05 s. Maximal lateral sway and anteroposterior sway were determined and the sway velocity calculated over 1-min trial periods. Body sway was measured under each of the following conditions: (1) normal laboratory lighting (186 lx); (2) moderate lighting (10 lx); (3) dim lighting (1 lx); (4) eyes closed, and (5) repeating pattern projected onto a wall. Each measure of the postural stability was significantly poorer in condition 4 (eyes closed) than in all other conditions. Anteroposterior sway was greater in condition 3 than in conditions 1 and 2, whilst the sway velocity was greater in condition 3 than in condition 2. Lateral sway did not differ significantly between different lighting levels (conditions 1-3). A projected repeating pattern (condition 5) did not significantly influence the postural stability relative to condition 1. The substantially greater body sway with eyes closed than with eyes open confirms the importance of vision in maintaining the postural stability. At the lowest light level, the body sway was significantly increased as compared with the other light levels, but was still substantially smaller than on closing the eyes. A projected repeating pattern did not influence the postural stability. Dim lighting levels and removing visual input appear to be associated with a poorer postural stability in older people and hence might be associated with an increased risk of falls. Copyright 2002 S. Karger AG, Basel

Rapid innate defensive responses of mice to looming visual stimuli.

PubMed

Yilmaz, Melis; Meister, Markus

2013-10-21

Much of brain science is concerned with understanding the neural circuits that underlie specific behaviors. While the mouse has become a favorite experimental subject, the behaviors of this species are still poorly explored. For example, the mouse retina, like that of other mammals, contains ∼20 different circuits that compute distinct features of the visual scene [1, 2]. By comparison, only a handful of innate visual behaviors are known in this species--the pupil reflex [3], phototaxis [4], the optomotor response [5], and the cliff response [6]--two of which are simple reflexes that require little visual processing. We explored the behavior of mice under a visual display that simulates an approaching object, which causes defensive reactions in some other species [7, 8]. We show that mice respond to this stimulus either by initiating escape within a second or by freezing for an extended period. The probability of these defensive behaviors is strongly dependent on the parameters of the visual stimulus. Directed experiments identify candidate retinal circuits underlying the behavior and lead the way into detailed study of these neural pathways. This response is a new addition to the repertoire of innate defensive behaviors in the mouse that allows the detection and avoidance of aerial predators. Copyright © 2013 Elsevier Ltd. All rights reserved.

Fall Preventive Exercise With or Without Behavior Change Support for Community-Dwelling Older Adults: A Randomized Controlled Trial With Short-Term Follow-up.

PubMed

Arkkukangas, Marina; Söderlund, Anne; Eriksson, Staffan; Johansson, Ann-Christin

2017-02-27

In Western countries, falls and fall-related injuries are a well-known threat to health in the aging population. Studies indicate that regular exercise improves strength and balance and can therefore decrease the incidence of falls and fall-related injuries. The challenge, however, is to provide exercise programs that are safe, effective, and attractive to the older population. The aim of this study was to investigate the short-term effect of a home-based exercise program with or without motivational interviewing (MI) compared with standard care on physical performance, fall self-efficacy, balance, activity level, handgrip strength, adherence to the exercise, and fall frequency. A total of 175 older adults participated in this randomized controlled study. They were randomly allocated for the Otago Exercise Program (OEP) (n = 61), OEP combined with MI (n = 58), or a control group (n = 56). The participants' mean age was 83 years. The recruitment period was from October 2012 to May 2015. Measurements of physical performance, fall self-efficacy, balance, activity level, handgrip strength, adherence to the exercise, and fall frequency were done before and 12 weeks after randomization. A total of 161 participants were followed up, and there were no significant differences between groups after a period of 12 weeks of regular exercise. Within the OEP + MI group, physical performance, fall self-efficacy, physical activity level, and handgrip strength improved significantly; likewise, improved physical performance and fall self-efficacy were found in the control group. A corresponding difference did not occur in the OEP group. Adherence to the exercise was generally high in both exercise groups. In the short-term perspective, there were no benefits of an exercise program with or without MI regarding physical performance, fall self-efficacy, activity level, handgrip strength, adherence to the exercise, and fall frequency in comparison to a control group. However, some small effects occurred within the OEP + MI group, indicating that there may be some possible value in behavioral change support combined with exercise in older adults that requires further evaluation in both short- and long-term studies.

Dealing with Disruptive Behavior of Adult Learners

ERIC Educational Resources Information Center

Dobmeier, Robert; Moran, Joseph

2008-01-01

The adult education literature on disruptive behavior of adult learners was reviewed and a survey on disruptive behavior of adult learners was conducted with adult educators. The findings are synthesized in a conceptual framework for understanding the types and causes of disruptive behavior, which fall into the categories of inattention,…

Effectiveness of a Play Therapy Intervention on Children's Externalizing and Off-Task Behaviors

ERIC Educational Resources Information Center

Meany-Walen, Kristin K.; Teeling, Sunny; Davis, Aubrey; Artley, George; Vignovich, Andrea

2017-01-01

Children's externalizing and off-task behaviors are deemed a major concern for elementary teachers and interfere with the classroom learning environment (Abidin & Robinson, 2002; Shillingford-Butler & Theodore, 2013). Children with these behaviors are at risk of falling behind academically and experiencing ongoing behavioral problems…

Child behavior check list and Korean personality inventory for children with functional visual loss.

PubMed

Kyung, Sung Eun; Lee, Sang Mi; Lim, Myung Ho

2014-08-01

To investigate the clinical psychiatric characteristics of children with the main complaint of functional visual loss, their behavior and personality were evaluated by the means of the Korean child behavior check list (K-CBCL), and the Korean personality inventory for children (KPI-C). The evaluation was carried out by the K-CBCL and the KPI-C, the domestically standardized tools, with 20 child subjects suspected of functional visual loss, among the patients who visited our hospital, between August, 2005 and December, 2012. The control group included 160 children in general schools of the same region. The 20 patients whose main complaint was functional visual loss were diagnosed as having a functional visual disorder. The child patient group showed a higher score for the K-CBCL and KPI-C sub-scales of somatic complaints, social problems, aggressive behavior, internalizing problems, externalizing problems, total behavioral problems, somatization and hyperactivity, than that of the control group. The results of the K-CBCL and KPI-C tests among children with functional visual loss, were significantly different from those of the normal control group. This result suggested that psychological factors may influence children with a main complaint of functional visual loss.

Investigating the fall-injury reducing effect of impact absorbing flooring among female nursing home residents: initial results.

PubMed

Gustavsson, Johanna; Bonander, Carl; Andersson, Ragnar; Nilson, Finn

2015-10-01

Fall-related injuries affect the lives of elderly to a substantial degree. This quasi-experimental study investigates the fall-injury reducing effect of impact absorbing flooring among female nursing home residents. The intervention site is a nursing home in Sweden where impact absorbing flooring was installed in parts of one of six wards (six out of 10 apartments (excluding bathrooms), the communal dining-room and parts of the corridor). The impact absorbing flooring is a 12 mm thick closed cell flexible polyurethane/polyurea composite tile (500×500 mm) with an exterior surface of polyurethane/polyurea. A generalised linear model (log-binomial) was used to calculate the RR of injury from falls on impact absorbing flooring compared to falls on regular flooring, adjusted for age, body mass index, visual and cognitive impairments. During the study period (1 October 2011 to 31 March 2014), 254 falls occurred on regular flooring and 77 falls on impact absorbing flooring. The injury/fall rate was 30.3% for falls on regular flooring and 16.9% for falls on impact absorbing flooring. Adjusted for covariates, the impact absorbing flooring significantly reduced the RR of injury in the event of a fall by 59% (RR 0.41 (95% Cl 0.20 to 0.80)). This is, to our knowledge, the first study evaluating the injury-reducing effect of impact absorbing flooring in a nursing home showing statistically significant effect. The results from this study are promising, indicating the considerable potential of impact absorbing flooring as a fall-related injury intervention among frail elderly. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

A multicenter study on the health-related quality of life of cataract patients: baseline data.

PubMed

Yamada, Masakazu; Mizuno, Yoshinobu; Miyake, Yozo

2009-09-01

This study examines the impact of cataracts on health-related quality of life (HR-QOL) and health events in the older population. The study population consisted of 439 unoperated cataract patients aged 60 years or older who visited any of the facilities affiliated with the Cataract Survey Group of the National Hospital Organization of Japan, which has been conducting a prospective multicenter cohort study on cataract patients. HR-QOL of the patients was assessed using the Japanese version of Visual Function Questionnaire-25 (VFQ-25) and the 8-Item Short-Form Health Survey (SF-8). The health condition and health events of the patients were also investigated. The average age of the 439 patients enrolled (126 men and 313 women) was 73.0 +/- 7.1 years. There were 323 patients with comorbidities (73.6%), 81 of whom (23.7%) felt it was hard to visit the hospital owing to their visual impairment. In the previous year, 74 patients (16.9%) had experienced a fall and 14 (3.2%) had been in a traffic accident. Of those, 43.2% and 8.3% respectively answered that the falls and the accident could have been triggered by their visual impairment. When the patients were classified according to visual acuity, most of the VFQ-25 subscale scores declined significantly with decreasing visual acuity, whereas the SF-8 scores showed no significant change. The participants of this study were patients with unoperated cataract, and thus the decline of HR-QOL was modest. The survey of health events, however, revealed that the visual constraint has a certain impact on the daily lives of the older population.

Visual Data Exploration for Balance Quantification in Real-Time During Exergaming.

PubMed

Soancatl Aguilar, Venustiano; J van de Gronde, Jasper; J C Lamoth, Claudine; van Diest, Mike; M Maurits, Natasha; B T M Roerdink, Jos

2017-01-01

Unintentional injuries are among the ten leading causes of death in older adults; falls cause 60% of these deaths. Despite their effectiveness to improve balance and reduce the risk of falls, balance training programs have several drawbacks in practice, such as lack of engaging elements, boring exercises, and the effort and cost of travelling, ultimately resulting in low adherence. Exergames, that is, digital games controlled by body movements, have been proposed as an alternative to improve balance. One of the main challenges for exergames is to automatically quantify balance during game-play in order to adapt the game difficulty according to the skills of the player. Here we perform a multidimensional exploratory data analysis, using visualization techniques, to find useful measures for quantifying balance in real-time. First, we visualize exergaming data, derived from 400 force plate recordings of 40 participants from 20 to 79 years and 10 trials per participant, as heat maps and violin plots to get quick insight into the nature of the data. Second, we extract known and new features from the data, such as instantaneous speed, measures of dispersion, turbulence measures derived from speed, and curvature values. Finally, we analyze and visualize these features using several visualizations such as a heat map, overlapping violin plots, a parallel coordinate plot, a projection of the two first principal components, and a scatter plot matrix. Our visualizations and findings suggest that heat maps and violin plots can provide quick insight and directions for further data exploration. The most promising measures to quantify balance in real-time are speed, curvature and a turbulence measure, because these measures show age-related changes in balance performance. The next step is to apply the present techniques to data of whole body movements as recorded by devices such as Kinect.

Visual Data Exploration for Balance Quantification in Real-Time During Exergaming

PubMed Central

J. van de Gronde, Jasper; J. C. Lamoth, Claudine; van Diest, Mike; M. Maurits, Natasha; B. T. M. Roerdink, Jos

2017-01-01

Unintentional injuries are among the ten leading causes of death in older adults; falls cause 60% of these deaths. Despite their effectiveness to improve balance and reduce the risk of falls, balance training programs have several drawbacks in practice, such as lack of engaging elements, boring exercises, and the effort and cost of travelling, ultimately resulting in low adherence. Exergames, that is, digital games controlled by body movements, have been proposed as an alternative to improve balance. One of the main challenges for exergames is to automatically quantify balance during game-play in order to adapt the game difficulty according to the skills of the player. Here we perform a multidimensional exploratory data analysis, using visualization techniques, to find useful measures for quantifying balance in real-time. First, we visualize exergaming data, derived from 400 force plate recordings of 40 participants from 20 to 79 years and 10 trials per participant, as heat maps and violin plots to get quick insight into the nature of the data. Second, we extract known and new features from the data, such as instantaneous speed, measures of dispersion, turbulence measures derived from speed, and curvature values. Finally, we analyze and visualize these features using several visualizations such as a heat map, overlapping violin plots, a parallel coordinate plot, a projection of the two first principal components, and a scatter plot matrix. Our visualizations and findings suggest that heat maps and violin plots can provide quick insight and directions for further data exploration. The most promising measures to quantify balance in real-time are speed, curvature and a turbulence measure, because these measures show age-related changes in balance performance. The next step is to apply the present techniques to data of whole body movements as recorded by devices such as Kinect. PMID:28135284

[Visual cues as a therapeutic tool in Parkinson's disease. A systematic review].

PubMed

Muñoz-Hellín, Elena; Cano-de-la-Cuerda, Roberto; Miangolarra-Page, Juan Carlos

2013-01-01

Sensory stimuli or sensory cues are being used as a therapeutic tool for improving gait disorders in Parkinson's disease patients, but most studies seem to focus on auditory stimuli. The aim of this study was to conduct a systematic review regarding the use of visual cues over gait disorders, dual tasks during gait, freezing and the incidence of falls in patients with Parkinson to obtain therapeutic implications. We conducted a systematic review in main databases such as Cochrane Database of Systematic Reviews, TripDataBase, PubMed, Ovid MEDLINE, Ovid EMBASE and Physiotherapy Evidence Database, during 2005 to 2012, according to the recommendations of the Consolidated Standards of Reporting Trials, evaluating the quality of the papers included with the Downs & Black Quality Index. 21 articles were finally included in this systematic review (with a total of 892 participants) with variable methodological quality, achieving an average of 17.27 points in the Downs and Black Quality Index (range: 11-21). Visual cues produce improvements over temporal-spatial parameters in gait, turning execution, reducing the appearance of freezing and falls in Parkinson's disease patients. Visual cues appear to benefit dual tasks during gait, reducing the interference of the second task. Further studies are needed to determine the preferred type of stimuli for each stage of the disease. Copyright © 2012 SEGG. Published by Elsevier Espana. All rights reserved.

Glaucoma and quality of life: fall and driving risk.

PubMed

Montana, Cynthia L; Bhorade, Anjali M

2018-03-01

Numerous population-based studies suggest that glaucoma is an independent risk factor for falling and motor vehicle collisions, particularly for older adults. These adverse events lead to increased healthcare expenditures and decreased quality of life. Current research priorities, therefore, include identifying factors that predispose glaucoma patients to falling and unsafe driving, and developing screening strategies and targeted rehabilitation. The purpose of this article is to review recent studies that address these priorities. Studies continue to support that glaucoma patients, particularly those with advanced disease, have an increased risk of falling or unsafe driving. Risk factors, however, remain variable and include severity and location of visual field defects, contrast sensitivity, and performance on divided attention tasks. Such variability is likely because of the multifactorial nature of ambulating and driving and compensatory strategies used by patients. Falls and unsafe driving remain a serious public health issue for older adults with glaucoma. Ambulation and driving are complex tasks and there is no consensus yet, regarding the best methods for risk stratification and targeted interventions to increase safety. Therefore, comprehensive and individualized assessments are recommended to most effectively evaluate a patient's risk for falling or unsafe driving.

Surfing-related ocular injuries.

PubMed

Kim, J W; McDonald, H R; Rubsamen, P E; Luttrull, J K; Drouilhet, J H; Frambach, D A; Boyer, D S; Lambrou, F H; Hendrick, A; Weiss, J N; Engstrom, R E; Ing, M

1998-01-01

This report evaluates the clinical characteristics of surfing-related ocular trauma to learn the nature of such injuries and propose possible preventive measures. The authors reviewed 11 cases of surfing-related eye injuries caused by direct trauma from the surfboard, studying their mechanism of injury, the associated ocular complications, and the anatomic and visual outcomes of surgical repair. Surfing-related ocular injuries occurred exclusively in young males (mean age, 24.8 years; range, 14-37 years). The mechanism of injury most frequently responsible was impact with the sharp nose of the surfboard following a fall. Serious posterior segment complications were observed in all 11 patients, with nine patients suffering ruptured globes. Despite immediate medical attention, five patients did not recover ambulatory levels of visual acuity (>5/200). Surfing-related ocular trauma presenting to the retinal specialist typically leaves the patient with a permanent visual disability. Important factors contributing to these high-velocity injuries include the sharply pointed nose of the surfboard and the leash keeping the surfer in close proximity to the board following a fall. A simple modification in surfboard design such as blunting the sharp nose of the surfboard, or appropriate protective guards fitted over the surfboard nose, should lessen the severity of such injuries.

Different protocols for analyzing behavior and adaptability in obstacle crossing in Parkinson's disease.

PubMed

Mollaei, Nafiseh; Bicho, Estela; Sousa, Nuno; Gago, Miguel Fernandes

2017-01-01

Imbalance and tripping over obstacles as a result of altered gait in older adults, especially in patients with Parkinson's disease (PD), are one of the most common causes of falls. During obstacle crossing, patients with PD modify their behavior in order to decrease the mechanical demands and enhance dynamic stability. Various descriptions of dynamic traits of gait that have been collected over longer periods, probably better synthesize the underlying structure and pattern of fluctuations in gait and can be more sensitive markers of aging or early neurological dysfunction and increased risk of falls. This confirmation challenges the clinimetric of different protocols and paradigms used for gait analysis up till now, in particular when analyzing obstacle crossing. The authors here present a critical review of current knowledge concerning the interplay between the cognition and gait in aging and PD, emphasizing the differences in gait behavior and adaptability while walking over different and challenging obstacle paradigms, and the implications of obstacle negotiation as a predictor of falls. Some evidence concerning the effectiveness of future rehabilitation protocols on reviving obstacle crossing behavior by trial and error relearning, taking advantage of dual-task paradigms, physical exercise, and virtual reality have been put forward in this article.

Assessing the resolution of haplotype distributions to delineate fall armyworm (Lepidoptera:Noctuidae) migratory behaviors

USDA-ARS?s Scientific Manuscript database

Regions of southern Florida and southern Texas (extending into Mexico) provide the overwintering source populations for virtually all fall armyworm infestations affecting the continental U.S. Understanding how these migratory populations annually disperse is important to predict and control infestat...

Use of fall risk increasing drugs in residents of retirement villages: a pilot study of long term care and retirement home residents in Ontario, Canada.

PubMed

Rojas-Fernandez, Carlos; Dadfar, Farzan; Wong, Andrea; Brown, Susan G

2015-10-14

Falls continue to be a problem for older people in long-term care (LTC) and retirement home (RH) settings and are associated with significant morbidity and health care use. Fall-risk increasing drugs (FRIDs) are known to increase fall risk and represent modifiable risk factors. There are limited data regarding the use of FRIDs in contemporary LTC and RH settings, and it has not been well documented to what extent medication regimens are reviewed and modified for those who have sustained falls. The objective of this study is to characterize medication related fall risk factors in LTC and RH residents and on-going use of medications known to increase fall risk. Retrospective chart review of residents aged >65 who sustained one or more falls living in LTC or RH settings. 105 residents who fell one or more times during 2009-2010 were identified with a mean age of 89 years, a mean of nine scheduled medications and seven diagnoses, and 83% were women. Residents in LTC were ostensibly at higher risk for falls relative to those in RH settings as suggested by higher proportion of residents with multiple falls, multiple comorbidities, comorbidities that increase fall risk and visual impairment. Post fall injuries were sustained by 42% of residents, and residents in RH sustained more injuries relative to LTC residents (47 vs 34%). Use of FRIDs such as benzodiazepines, antipsychotic, antidepressant and various antihypertensive drugs was common in the present sample. No medication regimen changes were noted in the 6-month post fall period. The present study documented common use FRIDs by LTC and RH residents with multiple falls. These potentially modifiable falls risk factors are not being adequately addressed in contemporary practice, demonstrating that there is much room for improvement with regards to the safe and appropriate use of medications in LTC and RH residents.

Insights into the Feelings, Thoughts, and Behaviors of Children with Visual Impairments: A Focus Group Study Prior to Adapting a Cognitive Behavior Therapy-Based Anxiety Intervention

ERIC Educational Resources Information Center

Visagie, Lisa; Loxton, Helene; Stallard, Paul; Silverman, Wendy K.

2017-01-01

Introduction: Anxiety is the most common psychological problem reported among children with visual impairments. Although cognitive behavior therapy interventions have proven successful in treating childhood anxiety, it is unclear whether they are suitable and accessible for children who have visual impairments. This study aimed to determine if and…

Research progress on Drosophila visual cognition in China.

PubMed

Guo, AiKe; Zhang, Ke; Peng, YueQin; Xi, Wang

2010-03-01

Visual cognition, as one of the fundamental aspects of cognitive neuroscience, is generally associated with high-order brain functions in animals and human. Drosophila, as a model organism, shares certain features of visual cognition in common with mammals at the genetic, molecular, cellular, and even higher behavioral levels. From learning and memory to decision making, Drosophila covers a broad spectrum of higher cognitive behaviors beyond what we had expected. Armed with powerful tools of genetic manipulation in Drosophila, an increasing number of studies have been conducted in order to elucidate the neural circuit mechanisms underlying these cognitive behaviors from a genes-brain-behavior perspective. The goal of this review is to integrate the most important studies on visual cognition in Drosophila carried out in mainland China during the last decade into a body of knowledge encompassing both the basic neural operations and circuitry of higher brain function in Drosophila. Here, we consider a series of the higher cognitive behaviors beyond learning and memory, such as visual pattern recognition, feature and context generalization, different feature memory traces, salience-based decision, attention-like behavior, and cross-modal leaning and memory. We discuss the possible general gain-gating mechanism implementing by dopamine - mushroom body circuit in fly's visual cognition. We hope that our brief review on this aspect will inspire further study on visual cognition in flies, or even beyond.

Predicting Use of Outdoor Fall Prevention Strategies: Considerations for Prevention Practices.

PubMed

Chippendale, Tracy

2018-01-01

Outdoor falls are just as common as indoor falls, but have received less attention in research and practice. Behavioral strategies play an important role in outdoor fall prevention. The purpose of this study was to examine predictors of strategy use. Backward stepwise regression was used to study factors associated with use of outdoor fall prevention strategies among a random sample ( N = 120) of community-dwelling seniors. Significant negative predictors of strategy use included higher education levels ( p < .01) and living in an urban versus a suburban environment ( p < .01). Concern about falls and number of identified risks were positive predictors ( ps < .05). Differences were found between outdoor fallers and nonfallers in the use of three different types of strategies ( ps < .05). There are some differences in the profiles of people who use and do not use outdoor fall prevention strategies. Further study of additional factors is warranted.

Effects of ambient stimuli on measures of behavioral state and microswitch use in adults with profound multiple impairments.

PubMed

Murphy, Kathleen M; Saunders, Muriel D; Saunders, Richard R; Olswang, Lesley B

2004-01-01

The effects of different types and amounts of environmental stimuli (visual and auditory) on microswitch use and behavioral states of three individuals with profound multiple impairments were examined. The individual's switch use and behavioral states were measured under three setting conditions: natural stimuli (typical visual and auditory stimuli in a recreational situation), reduced visual stimuli, and reduced visual and auditory stimuli. Results demonstrated differential switch use in all participants with the varying environmental setting conditions. No consistent effects were observed in behavioral state related to environmental condition. Predominant behavioral state scores and switch use did not systematically covary with any participant. Results suggest the importance of considering environmental stimuli in relationship to switch use when working with individuals with profound multiple impairments.

Cost-effectiveness in fall prevention for older women.

PubMed

Hektoen, Liv F; Aas, Eline; Lurås, Hilde

2009-08-01

The aim of this study was to estimate the cost-effectiveness of implementing an exercise-based fall prevention programme for home-dwelling women in the > or = 80-year age group in Norway. The impact of the home-based individual exercise programme on the number of falls is based on a New Zealand study. On the basis of the cost estimates and the estimated reduction in the number of falls obtained with the chosen programme, we calculated the incremental costs and the incremental effect of the exercise programme as compared with no prevention. The calculation of the average healthcare cost of falling was based on assumptions regarding the distribution of fall injuries reported in the literature, four constructed representative case histories, assumptions regarding healthcare provision associated with the treatment of the specified cases, and estimated unit costs from Norwegian cost data. We calculated the average healthcare costs per fall for the first year. We found that the reduction in healthcare costs per individual for treating fall-related injuries was 1.85 times higher than the cost of implementing a fall prevention programme. The reduction in healthcare costs more than offset the cost of the prevention programme for women aged > or = 80 years living at home, which indicates that health authorities should increase their focus on prevention. The main intention of this article is to stipulate costs connected to falls among the elderly in a transparent way and visualize the whole cost picture. Cost-effectiveness analysis is a health policy tool that makes politicians and other makers of health policy conscious of this complexity.

Lighting and perceptual cues: Effects on gait measures of older adults at high and low risk for falls

PubMed Central

2011-01-01

Background The visual system plays an important role in maintaining balance. As a person ages, gait becomes slower and stride becomes shorter, especially in dimly lighted environments. Falls risk has been associated with reduced speed and increased gait variability. Methods Twenty-four older adults (half identified at risk for falls) experienced three lighting conditions: pathway illuminated by 1) general ceiling-mounted fixtures, 2) conventional plug-in night lights and 3) plug-in night lights supplemented by laser lines outlining the pathway. Gait measures were collected using the GAITRite© walkway system. Results Participants performed best under the general ceiling-mounted light system and worst under the night light alone. The pathway plus night lights increased gait velocity and reduced step length variability compared to the night lights alone in those at greater risk of falling. Conclusions Practically, when navigating in more challenging environments, such as in low-level ambient illumination, the addition of perceptual cues that define the horizontal walking plane can potentially reduce falls risks in older adults. PMID:21864387

Thought Experiments in Teaching Free-Fall Weightlessness: A Critical Review and an Exploration of Mercury's Behavior in "Falling Elevator"

ERIC Educational Resources Information Center

Balukovic, Jasmina; Slisko, Josip; Cruz, Adrián Corona

2017-01-01

Different "thought experiments" dominate teaching approaches to weightlessness, reducing students' opportunities for active physics learning, which should include observations, descriptions, explanations and predictions of real phenomena. Besides the controversy related to conceptual definitions of weight and weightlessness, we report…

Adaptive Behavior of Children and Adolescents with Visual Impairments

ERIC Educational Resources Information Center

Papadopoulos, Konstantinos; Metsiou, Katerina; Agaliotis, Ioannis

2011-01-01

The present study explored the total adaptive behavior of children and adolescents with visual impairments, as well as their adaptive behavior in each of the domains of Communication, Daily Living Skills, and Socialization. Moreover, the predictors of the performance and developmental delay in adaptive behavior were investigated. Instrumentation…

Single Stance Stability and Proprioceptive Control in Older Adults Living at Home: Gender and Age Differences

PubMed Central

Riva, Dario; Mamo, Carlo; Fanì, Mara; Saccavino, Patrizia; Rocca, Flavio; Momenté, Manuel; Fratta, Marianna

2013-01-01

In developed countries, falls in older people represent a rising problem. As effective prevention should start before the risk becomes evident, an early predictor is needed. Single stance instability would appear as a major risk factor. Aims of the study were to describe single stance stability, its sensory components, and their correlation with age and gender. A random sample of 597 older adults (319 men, 278 women) living at home, aged 65–84, was studied. Stability tests were performed with an electronic postural station. The single stance test showed the impairment of single stance stability in older individuals (75–84 yrs). The significant decline of stability in the older subjects may be explained by the impairment of proprioceptive control together with the decrease in compensatory visual stabilization and emergency responses. Younger subjects (65–74 yrs) exhibited better, but still inadequate, proprioceptive control with compensatory visual stabilization. Gender differences appeared in older subjects: women were significantly less stable than men. The measurement of the sensory components of single stance stability could aid in the early detection of a decay in antigravity movements many years before the risk of falling becomes evident. Adequate proprioceptive control could mitigate the effects of all other risks of falling. PMID:23984068

Assessment of postural instability in patients with Parkinson's disease.

PubMed

Błaszczyk, J W; Orawiec, R; Duda-Kłodowska, D; Opala, G

2007-10-01

Postural instability is one of the most disabling features of idiopathic Parkinson's disease (PD). In this study, we focused on postural instability as the main factor predisposing parkinsonians to falls. For this purpose, changes in sway characteristics during quiet stance due to visual feedback exclusion were studied. We searched for postural sway measures that could be potential discriminators for an increased fall risk. A group of 110 subjects: 55 parkinsonians (Hoehn and Yahr: 1-3), and 55 age-matched healthy volunteers participated in the experiment. Their spontaneous sway characteristics while standing quiet with eyes open and eyes closed were analyzed. We found that an increased mediolateral sway and sway area while standing with eyes closed are characteristic of parkinsonian postural instability and may serve to quantify well a tendency to fall. These sway indices significantly correlated with disease severity rated both by the Hoehn and Yahr scale as well as by the Motor Section of the UPDRS. A forward shift of a mean COP position in parkinsonians which reflects their flexed posture was also significantly greater to compare with the elderly subjects and exhibited a high sensitivity to visual conditions. Both groups of postural sway abnormalities identified here may be used as accessible and reliable measures which allow for quantitative assessment of postural instability in Parkinson's disease.

Feasibility of interdisciplinary community-based fall risk screening.

PubMed

Elliott, Sharon J; Ivanescu, Andrada; Leland, Natalie E; Fogo, Jennifer; Painter, Jane A; Trujillo, Leonard G

2012-01-01

This pilot study examined the feasibility of (1) conducting interdisciplinary fall risk screens at a communitywide adult fall prevention event and (2) collecting preliminary follow-up data from people screened at the event about balance confidence and home and activity modifications made after receiving educational information at the event. We conducted a pilot study with pre- and posttesting (4-mo follow-up) with 35 community-dwelling adults ≥55 yr old. Approximately half the participants were at risk for falls. Most participants who anticipated making environmental or activity changes to reduce fall risk initiated changes (n = 8/11; 72.7%) during the 4-mo follow-up period. We found no significant difference in participants' balance confidence between baseline (median = 62.81) and follow-up (median = 64.06) as measured by the Activities-specific Balance Confidence scale. Conducting interdisciplinary fall risk screens at an adult fall prevention event is feasible and can facilitate environmental and behavior changes to reduce fall risk. Copyright © 2012 by the American Occupational Therapy Association, Inc.

Person-environment interactions contributing to nursing home resident falls.

PubMed

Hill, Elizabeth E; Nguyen, Tam H; Shaha, Maya; Wenzel, Jennifer A; DeForge, Bruce R; Spellbring, Ann Marie

2009-10-01

Although approximately 50% of nursing home residents fall annually, the surrounding circumstances remain inadequately understood. This study explored nursing staff perspectives of person, environment, and interactive circumstances surrounding nursing home falls. Focus groups were conducted at two nursing homes in the mid-Atlantic region with the highest and lowest fall rates among corporate facilities. Two focus groups were conducted per facility: one with licensed nurses and one with geriatric nursing assistants. Thematic and content analysis revealed three themes and 11 categories. Three categories under the Person theme were Change in Residents' Health Status, Decline in Residents' Abilities, and Residents' Behaviors and Personality Characteristics. There were five Nursing Home Environment categories: Design Safety, Limited Space, Obstacles, Equipment Misuse and Malfunction, and Staff and Organization of Care. Three Interactions Leading to Falls categories were identified: Reasons for Falls, Time of Falls, and High-Risk Activities. Findings highlight interactions between person and environment factors as significant contributors to resident falls. Copyright 2009, SLACK Incorporated.

Prenatal sensory experience affects hatching behavior in domestic chicks (Gallus gallus) and Japanese quail chicks (Coturnix coturnix japonica).

PubMed

Sleigh, Merry J; Casey, Michael B

2014-07-01

Species-typical developmental outcomes result from organismic and environmental constraints and experiences shared by members of a species. We examined the effects of enhanced prenatal sensory experience on hatching behaviors by exposing domestic chicks (n = 95) and Japanese quail (n = 125) to one of four prenatal conditions: enhanced visual stimulation, enhanced auditory stimulation, enhanced auditory and visual stimulation, or no enhanced sensory experience (control condition). In general, across species, control embryos had slower hatching behaviors than all other embryos. Embryos in the auditory condition had faster hatching behaviors than embryos in the visual and control conditions. Auditory-visual condition embryos showed similarities to embryos exposed to either auditory or visual stimulation. These results suggest that prenatal sensory experience can influence hatching behavior of precocial birds, with the type of stimulation being a critical variable. These results also provide further evidence that species-typical outcomes are the result of species-typical prenatal experiences. © 2013 Wiley Periodicals, Inc.

Visual projection neurons in the Drosophila lobula link feature detection to distinct behavioral programs

PubMed Central

Wu, Ming; Nern, Aljoscha; Williamson, W Ryan; Morimoto, Mai M; Reiser, Michael B; Card, Gwyneth M; Rubin, Gerald M

2016-01-01

Visual projection neurons (VPNs) provide an anatomical connection between early visual processing and higher brain regions. Here we characterize lobula columnar (LC) cells, a class of Drosophila VPNs that project to distinct central brain structures called optic glomeruli. We anatomically describe 22 different LC types and show that, for several types, optogenetic activation in freely moving flies evokes specific behaviors. The activation phenotypes of two LC types closely resemble natural avoidance behaviors triggered by a visual loom. In vivo two-photon calcium imaging reveals that these LC types respond to looming stimuli, while another type does not, but instead responds to the motion of a small object. Activation of LC neurons on only one side of the brain can result in attractive or aversive turning behaviors depending on the cell type. Our results indicate that LC neurons convey information on the presence and location of visual features relevant for specific behaviors. DOI: http://dx.doi.org/10.7554/eLife.21022.001 PMID:28029094

Effect of season on reproductive behaviors and fertilization success in cavies (Cavia aperea).

PubMed

Hribal, Romy; Rübensam, Kathrin; Bernhardt, Sandra; Jewgenow, Katarina; Guenther, Anja

2018-04-05

Finding the optimal timing for breeding is crucial for small mammals to ensure survival and maximize lifetime reproductive success. Species living in temperate regions therefore often restrict breeding to seasons with favorable food and weather conditions. Although caviomorph rodents such as guinea pigs are described as non-seasonal breeders, a series of recent publications has shown seasonal adaptations in litter size, offspring birth mass and maternal investment. Here, we aim to test if seasonal patterns of litter size variation found in earlier studies, are mediated by seasonal differences in female estrus length, fertilization rate and mating behavior. The female estrus period was longer in fall compared to all other seasons (p < 0.001), frequently lasting 7-9 days while estrus in spring usually lasted less than 2 days. In fall, females mated later during estrus (p < 0.001), resulting in reduced fertilization rates (p < 0.001). Fertilization rate was well above 95% in summer while it dropped to less than 85% in fall and winter. While none of the male mating characteristics such as number and duration of copulations differed across seasons, the number of mating bouts was reduced in fall (p = 0.04). Finally, the developmental stages of flushed embryos were more diverse in spring and summer compared to fall and winter. These results suggest that seasonal differences in fertilization rate and quality of implanted embryos are mediated by female estrus length and timing and intensity of mating behavior. Together, these effects contribute to the observed differences in litter size across seasons. Copyright © 2018 Elsevier Inc. All rights reserved.

A study of using smartphone to detect and identify construction workers' near-miss falls based on ANN

NASA Astrophysics Data System (ADS)

Zhang, Mingyuan; Cao, Tianzhuo; Zhao, Xuefeng

2018-03-01

As an effective fall accident preventive method, insight into near-miss falls provides an efficient solution to find out the causes of fall accidents, classify the type of near-miss falls and control the potential hazards. In this context, the paper proposes a method to detect and identify near-miss falls that occur when a worker walks in a workplace based on artificial neural network (ANN). The energy variation generated by workers who meet with near-miss falls is measured by sensors embedded in smart phone. Two experiments were designed to train the algorithm to identify various types of near-miss falls and test the recognition accuracy, respectively. At last, a test was conducted by workers wearing smart phones as they walked around a simulated construction workplace. The motion data was collected, processed and inputted to the trained ANN to detect and identify near-miss falls. Thresholds were obtained to measure the relationship between near-miss falls and fall accidents in a quantitate way. This approach, which integrates smart phone and ANN, will help detect near-miss fall events, identify hazardous elements and vulnerable workers, providing opportunities to eliminate dangerous conditions in a construction site or to alert possible victims that need to change their behavior before the occurrence of a fall accident.

[Effects of a fall prevention program on falls in frail elders living at home in rural communities].

PubMed

Yoo, Jae-Soon; Jeon, Mi Yang; Kim, Chul-Gyu

2013-10-01

This study was conducted to determine the effects of a fall prevention program on falls, physical function, psychological function, and home environmental safety in frail elders living at home in rural communities. The design of this study was a nonequivalent control group pre posttest design. The study was conducted from July to November, 2012 with 30 participants in the experimental group and 30 in the control group. Participants were registered at the public health center of E County. The prevention program on falls consisted of laughter therapy, exercise, foot care and education. The program was provided once a week for 8 weeks and each session lasted 80 minutes. The risk score for falls and depression in the experimental group decreased significantly compared with scores for the control group. Compliance with prevention behavior related to falls, knowledge score on falls, safety scores of home environment, physical balance, muscle strength of lower extremities, and self-efficacy for fall prevention significantly increased in the experimental group compared with the control group. These results suggest that the prevention program on falls is effective for the prevention of falls in frail elders living at home.

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

Neural discriminability in rat lateral extrastriate cortex and deep but not superficial primary visual cortex correlates with shape discriminability.

PubMed

Vermaercke, Ben; Van den Bergh, Gert; Gerich, Florian; Op de Beeck, Hans

2015-01-01

Recent studies have revealed a surprising degree of functional specialization in rodent visual cortex. It is unknown to what degree this functional organization is related to the well-known hierarchical organization of the visual system in primates. We designed a study in rats that targets one of the hallmarks of the hierarchical object vision pathway in primates: selectivity for behaviorally relevant dimensions. We compared behavioral performance in a visual water maze with neural discriminability in five visual cortical areas. We tested behavioral discrimination in two independent batches of six rats using six pairs of shapes used previously to probe shape selectivity in monkey cortex (Lehky and Sereno, 2007). The relative difficulty (error rate) of shape pairs was strongly correlated between the two batches, indicating that some shape pairs were more difficult to discriminate than others. Then, we recorded in naive rats from five visual areas from primary visual cortex (V1) over areas LM, LI, LL, up to lateral occipito-temporal cortex (TO). Shape selectivity in the upper layers of V1, where the information enters cortex, correlated mostly with physical stimulus dissimilarity and not with behavioral performance. In contrast, neural discriminability in lower layers of all areas was strongly correlated with behavioral performance. These findings, in combination with the results from Vermaercke et al. (2014b), suggest that the functional specialization in rodent lateral visual cortex reflects a processing hierarchy resulting in the emergence of complex selectivity that is related to behaviorally relevant stimulus differences.

WATESOL Journal, 1989-1994.

ERIC Educational Resources Information Center

WATESOL Journal, 1994

1994-01-01

"WATESOL" is an acronym for "Washington Area Teachers of English To Speakers of Other Languages." This document consists of the only three issues of the "WATESOL Journal" published from 1989 through 1994. Fall 1989 includes: (1) "The Visual Voices of Nonverbal Films" (Salvatore J. Parlato); (2)…

The neural basis of visual behaviors in the larval zebrafish

PubMed Central

Portugues, Ruben; Engert, Florian

2015-01-01

We review visually guided behaviors in larval zebrafish and summarise what is known about the neural processing that results in these behaviors, paying particular attention to the progress made in the last 2 years. Using the examples of the optokinetic reflex, the optomotor response, prey tracking and the visual startle response, we illustrate how the larval zebrafish presents us with a very promising model vertebrate system that allows neurocientists to integrate functional and behavioral studies and from which we can expect illuminating insights in the near future. PMID:19896836

Storyline Visualizations of Eye Tracking of Movie Viewing

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

Balint, John T.; Arendt, Dustin L.; Blaha, Leslie M.

Storyline visualizations offer an approach that promises to capture the spatio-temporal characteristics of individual observers and simultaneously illustrate emerging group behaviors. We develop a visual analytics approach to parsing, aligning, and clustering fixation sequences from eye tracking data. Visualization of the results captures the similarities and differences across a group of observers performing a common task. We apply our storyline approach to visualize gaze patterns of people watching dynamic movie clips. Storylines mitigate some of the shortcomings of existent spatio-temporal visualization techniques and, importantly, continue to highlight individual observer behavioral dynamics.

The Effect of Temporal Perception on Weight Perception

PubMed Central

Kambara, Hiroyuki; Shin, Duk; Kawase, Toshihiro; Yoshimura, Natsue; Akahane, Katsuhito; Sato, Makoto; Koike, Yasuharu

2013-01-01

A successful catch of a falling ball requires an accurate estimation of the timing for when the ball hits the hand. In a previous experiment in which participants performed ball-catching task in virtual reality environment, we accidentally found that the weight of a falling ball was perceived differently when the timing of ball load force to the hand was shifted from the timing expected from visual information. Although it is well known that spatial information of an object, such as size, can easily deceive our perception of its heaviness, the relationship between temporal information and perceived heaviness is still not clear. In this study, we investigated the effect of temporal factors on weight perception. We conducted ball-catching experiments in a virtual environment where the timing of load force exertion was shifted away from the visual contact timing (i.e., time when the ball hit the hand in the display). We found that the ball was perceived heavier when force was applied earlier than visual contact and lighter when force was applied after visual contact. We also conducted additional experiments in which participants were conditioned to one of two constant time offsets prior to testing weight perception. After performing ball-catching trials with 60 ms advanced or delayed load force exertion, participants’ subjective judgment on the simultaneity of visual contact and force exertion changed, reflecting a shift in perception of time offset. In addition, timing of catching motion initiation relative to visual contact changed, reflecting a shift in estimation of force timing. We also found that participants began to perceive the ball as lighter after conditioning to 60 ms advanced offset and heavier after the 60 ms delayed offset. These results suggest that perceived heaviness depends not on the actual time offset between force exertion and visual contact but on the subjectively perceived time offset between them and/or estimation error in force timing. PMID:23450805

Describing Older Adults' Awareness of Fall Risk Using Situation Awareness Research Techniques: A Pilot Study.

PubMed

Azzarello, Jo; Hall, Beth

2016-07-01

The purpose of the current study was to evaluate efficacy of techniques adapted from situation awareness research for describing how older adults perceive and understand fall risk factors in the context of daily routine. Eleven older adults watched a video of an older woman performing daily activities. Thirteen intrinsic, extrinsic, and behavioral fall risks were embedded throughout the scenario. The video was periodically frozen/blanked from view while participants answered questions about their understanding of the situation and associated story elements. Participants perceived a variety of fall risk factors but did not necessarily interpret them as indicating fall risk. Many fall risks held non-fall meaning for participants (e.g., newspapers on the floor meant the woman liked to read). Although four participants readily identified a fall risk situation, seven did not until they were explicitly asked to consider safety. Study techniques were effective for describing situation awareness of fall risk and several suggestions for improvement are described. [Res Gerontol Nurs. 2016; 9(4):161-166.]. Copyright 2016, SLACK Incorporated.

Out of Mind, Out of Sight: Unexpected Scene Elements Frequently Go Unnoticed Until Primed.

PubMed

Slavich, George M; Zimbardo, Philip G

2013-12-01

The human visual system employs a sophisticated set of strategies for scanning the environment and directing attention to stimuli that can be expected given the context and a person's past experience. Although these strategies enable us to navigate a very complex physical and social environment, they can also cause highly salient, but unexpected stimuli to go completely unnoticed. To examine the generality of this phenomenon, we conducted eight studies that included 15 different experimental conditions and 1,577 participants in all. These studies revealed that a large majority of participants do not report having seen a woman in the center of an urban scene who was photographed in midair as she was committing suicide. Despite seeing the scene repeatedly, 46 % of all participants failed to report seeing a central figure and only 4.8 % reported seeing a falling person. Frequency of noticing the suicidal woman was highest for participants who read a narrative priming story that increased the extent to which she was schematically congruent with the scene. In contrast to this robust effect of inattentional blindness , a majority of participants reported seeing other peripheral objects in the visual scene that were equally difficult to detect, yet more consistent with the scene. Follow-up qualitative analyses revealed that participants reported seeing many elements that were not actually present, but which could have been expected given the overall context of the scene. Together, these findings demonstrate the robustness of inattentional blindness and highlight the specificity with which different visual primes may increase noticing behavior.

Changes in postural control in patients with Parkinson's disease: a posturographic study.

PubMed

Doná, F; Aquino, C C; Gazzola, J M; Borges, V; Silva, S M C A; Ganança, F F; Caovilla, H H; Ferraz, H B

2016-09-01

Postural instability is one of the most disabling features in Parkinson's disease (PD), and often leads to falls that reduce mobility and functional capacity. The objectives of this study were to analyse the limit of stability (LOS) and influence of the manipulation of visual, somatosensorial and visual-vestibular information on postural control in patients with PD and healthy subjects. Cross-sectional. Movement Disorders Unit, university setting. Eighty-two subjects aged between 37 and 83 years: 41 with Parkinson's disease in the 'on' state and 41 healthy subjects with no neurological disorders. Both groups were matched in terms of sex and age. Unified Parkinson's Disease Rating Scale (UPDRS)-motor score, modified Hoehn and Yahr staging, Dynamic Gait Index (DGI) and posturography with integrated virtual reality. The parameters analysed by posturography were LOS area, area of body centre of pressure excursion and balance functional reserve in the standing position in 10 conditions (open and closed eyes, unstable surface with eyes closed, saccadic and optokinetic stimuli, and visual-vestibular interaction). The mean UPDRS motor score and DGI score were 27 [standard deviation (SD) 14] and 21 (SD 3), respectively. Thirteen participants scored between 0 and 19 points, indicating major risk of falls. Posturographic assessment showed that patients with PD had significantly lower LOS area and balance functional reserve values, and greater body sway area in all posturographic conditions compared with healthy subjects. Patients with PD have reduced LOS area and greater postural sway compared with healthy subjects. The deterioration in postural control was significantly associated with major risk of falls. Copyright © 2015 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Sci-Fin: Visual Mining Spatial and Temporal Behavior Features from Social Media

PubMed Central

Pu, Jiansu; Teng, Zhiyao; Gong, Rui; Wen, Changjiang; Xu, Yang

2016-01-01

Check-in records are usually available in social services, which offer us the opportunity to capture and analyze users’ spatial and temporal behaviors. Mining such behavior features is essential to social analysis and business intelligence. However, the complexity and incompleteness of check-in records bring challenges to achieve such a task. Different from the previous work on social behavior analysis, in this paper, we present a visual analytics system, Social Check-in Fingerprinting (Sci-Fin), to facilitate the analysis and visualization of social check-in data. We focus on three major components of user check-in data: location, activity, and profile. Visual fingerprints for location, activity, and profile are designed to intuitively represent the high-dimensional attributes. To visually mine and demonstrate the behavior features, we integrate WorldMapper and Voronoi Treemap into our glyph-like designs. Such visual fingerprint designs offer us the opportunity to summarize the interesting features and patterns from different check-in locations, activities and users (groups). We demonstrate the effectiveness and usability of our system by conducting extensive case studies on real check-in data collected from a popular microblogging service. Interesting findings are reported and discussed at last. PMID:27999398

Sci-Fin: Visual Mining Spatial and Temporal Behavior Features from Social Media.

PubMed

Pu, Jiansu; Teng, Zhiyao; Gong, Rui; Wen, Changjiang; Xu, Yang

2016-12-20

Check-in records are usually available in social services, which offer us the opportunity to capture and analyze users' spatial and temporal behaviors. Mining such behavior features is essential to social analysis and business intelligence. However, the complexity and incompleteness of check-in records bring challenges to achieve such a task. Different from the previous work on social behavior analysis, in this paper, we present a visual analytics system, Social Check-in Fingerprinting (Sci-Fin), to facilitate the analysis and visualization of social check-in data. We focus on three major components of user check-in data: location, activity, and profile. Visual fingerprints for location, activity, and profile are designed to intuitively represent the high-dimensional attributes. To visually mine and demonstrate the behavior features, we integrate WorldMapper and Voronoi Treemap into our glyph-like designs. Such visual fingerprint designs offer us the opportunity to summarize the interesting features and patterns from different check-in locations, activities and users (groups). We demonstrate the effectiveness and usability of our system by conducting extensive case studies on real check-in data collected from a popular microblogging service. Interesting findings are reported and discussed at last.

An association between auditory-visual synchrony processing and reading comprehension: Behavioral and electrophysiological evidence

PubMed Central

Mossbridge, Julia; Zweig, Jacob; Grabowecky, Marcia; Suzuki, Satoru

2016-01-01

The perceptual system integrates synchronized auditory-visual signals in part to promote individuation of objects in cluttered environments. The processing of auditory-visual synchrony may more generally contribute to cognition by synchronizing internally generated multimodal signals. Reading is a prime example because the ability to synchronize internal phonological and/or lexical processing with visual orthographic processing may facilitate encoding of words and meanings. Consistent with this possibility, developmental and clinical research has suggested a link between reading performance and the ability to compare visual spatial/temporal patterns with auditory temporal patterns. Here, we provide converging behavioral and electrophysiological evidence suggesting that greater behavioral ability to judge auditory-visual synchrony (Experiment 1) and greater sensitivity of an electrophysiological marker of auditory-visual synchrony processing (Experiment 2) both predict superior reading comprehension performance, accounting for 16% and 25% of the variance, respectively. These results support the idea that the mechanisms that detect auditory-visual synchrony contribute to reading comprehension. PMID:28129060

An Association between Auditory-Visual Synchrony Processing and Reading Comprehension: Behavioral and Electrophysiological Evidence.

PubMed

Mossbridge, Julia; Zweig, Jacob; Grabowecky, Marcia; Suzuki, Satoru

2017-03-01

The perceptual system integrates synchronized auditory-visual signals in part to promote individuation of objects in cluttered environments. The processing of auditory-visual synchrony may more generally contribute to cognition by synchronizing internally generated multimodal signals. Reading is a prime example because the ability to synchronize internal phonological and/or lexical processing with visual orthographic processing may facilitate encoding of words and meanings. Consistent with this possibility, developmental and clinical research has suggested a link between reading performance and the ability to compare visual spatial/temporal patterns with auditory temporal patterns. Here, we provide converging behavioral and electrophysiological evidence suggesting that greater behavioral ability to judge auditory-visual synchrony (Experiment 1) and greater sensitivity of an electrophysiological marker of auditory-visual synchrony processing (Experiment 2) both predict superior reading comprehension performance, accounting for 16% and 25% of the variance, respectively. These results support the idea that the mechanisms that detect auditory-visual synchrony contribute to reading comprehension.

Optimism, Cynical Hostility, Falls, and Fractures: The Women's Health Initiative Observational Study (WHI-OS).

PubMed

Cauley, Jane A; Smagula, Stephen F; Hovey, Kathleen M; Wactawski-Wende, Jean; Andrews, Christopher A; Crandall, Carolyn J; LeBoff, Meryl S; Li, Wenjun; Coday, Mace; Sattari, Maryam; Tindle, Hilary A

2017-02-01

Traits of optimism and cynical hostility are features of personality that could influence the risk of falls and fractures by influencing risk-taking behaviors, health behaviors, or inflammation. To test the hypothesis that personality influences falls and fracture risk, we studied 87,342 women enrolled in WHI-OS. Optimism was assessed by the Life Orientation Test-Revised and cynical hostility, the cynicism subscale of the Cook-Medley questionnaire. Higher scores indicate greater optimism and hostility. Optimism and hostility were correlated at r = -0. 31, p < 0.001. Annual self-report of falling ≥2 times in the past year was modeled using repeated measures logistic regression. Cox proportional hazards models were used for the fracture outcomes. We examined the risk of falls and fractures across the quartiles (Q) of optimism and hostility with tests for trends; Q1 formed the referent group. The average follow-up for fractures was 11.4 years and for falls was 7.6 years. In multivariable (MV)-adjusted models, women with the highest optimism scores (Q4) were 11% less likely to report ≥2 falls in the past year (odds ratio [OR] = 0.89; 95% confidence intervals [CI] 0.85-0.90). Women in Q4 for hostility had a 12% higher risk of ≥2 falls (OR = 1.12; 95% CI 1.07-1.17). Higher optimism scores were also associated with a 10% lower risk of fractures, but this association was attenuated in MV models. Women with the greatest hostility (Q4) had a modest increased risk of any fracture (MV-adjusted hazard ratio = 1. 05; 95% CI 1.01-1.09), but there was no association with specific fracture sites. In conclusion, optimism was independently associated with a decreased risk of ≥2 falls, and hostility with an increased risk of ≥2 falls, independent of traditional risk factors. The magnitude of the association was similar to aging 5 years. Whether interventions aimed at attitudes could reduce fall risks remains to be determined. © 2016 American Society for Bone and Mineral Research. © 2016 American Society for Bone and Mineral Research.

Towards a social and context-aware multi-sensor fall detection and risk assessment platform.

PubMed

De Backere, F; Ongenae, F; Van den Abeele, F; Nelis, J; Bonte, P; Clement, E; Philpott, M; Hoebeke, J; Verstichel, S; Ackaert, A; De Turck, F

2015-09-01

For elderly people fall incidents are life-changing events that lead to degradation or even loss of autonomy. Current fall detection systems are not integrated and often associated with undetected falls and/or false alarms. In this paper, a social- and context-aware multi-sensor platform is presented, which integrates information gathered by a plethora of fall detection systems and sensors at the home of the elderly, by using a cloud-based solution, making use of an ontology. Within the ontology, both static and dynamic information is captured to model the situation of a specific patient and his/her (in)formal caregivers. This integrated contextual information allows to automatically and continuously assess the fall risk of the elderly, to more accurately detect falls and identify false alarms and to automatically notify the appropriate caregiver, e.g., based on location or their current task. The main advantage of the proposed platform is that multiple fall detection systems and sensors can be integrated, as they can be easily plugged in, this can be done based on the specific needs of the patient. The combination of several systems and sensors leads to a more reliable system, with better accuracy. The proof of concept was tested with the use of the visualizer, which enables a better way to analyze the data flow within the back-end and with the use of the portable testbed, which is equipped with several different sensors. Copyright © 2014 Elsevier Ltd. All rights reserved.

Using Visual Activity Schedules for Young Children with Challenging Behavior

ERIC Educational Resources Information Center

Zimmerman, Kathleen N.; Ledford, Jennifer R.; Barton, Erin E.

2017-01-01

Young children with challenging behavior may require individualized interventions to facilitate improved outcomes. Visual activity schedules (VAS) have been well documented for improving engagement, transition, and recreation behaviors with children with autism spectrum disorder (ASD) and intellectual disabilities (ID). However, children…

Marked colour divergence in the gliding membranes of a tropical lizard mirrors population differences in the colour of falling leaves.

PubMed

Klomp, D A; Stuart-Fox, D; Das, I; Ord, T J

2014-12-01

Populations of the Bornean gliding lizard, Draco cornutus, differ markedly in the colour of their gliding membranes. They also differ in local vegetation type (mangrove forest versus lowland rainforest) and consequently, the colour of falling leaves (red and brown/black in mangrove versus green, brown and black in rainforest). We show that the gliding membranes of these lizards closely match the colours of freshly fallen leaves in the local habitat as they appear to the visual system of birds (their probable predators). Furthermore, gliding membranes more closely resembled colours of local fallen leaves than standing foliage or fallen leaves in the other population's habitat. This suggests that the two populations have diverged in gliding membrane coloration to match the colours of their local falling leaves, and that mimicking falling leaves is an adaptation that functions to reduce predation by birds. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

A comparison of burn season effects on nesting birds in North Dakota mixed-grass prairie

USGS Publications Warehouse

Higgins, K.F.

1986-01-01

During 1982-1985, the effects of single spring and fall burn treatments on ground nesting birds and residual cover were studied on five paired areas of native mixed-grass prairie in northwestern Stutsman County, ND. Annually, visual obstruction readings to index the height-density of residual cover were taken once and nest searches were made four times on each area. Residual nesting cover on fall burn plots averaged taller and denser than on spring burn plots during post-fire growing years 2-4. A total of 259 duck nests and 63 nests of non-passerine birds were found during the four years. Duck nesting success was significantly greater (P < 0.05) in fall burn plots than in spring burn plots for all species and years combined. Too few nests of other bird species were found for valid comparisons. Results suggest that vegetation structure and duck nesting response to spring and fall burns became similar again by the third post-fire growing season.

Falling Less in Kansas: Development of a Fall Risk Reduction Toolkit

PubMed Central

Radebaugh, Teresa S.; Bahner, Candace A.; Ballard-Reisch, Deborah; Epp, Michael; Hale, LaDonna S.; Hanley, Rich; Kendrick, Karen; Rogers, Michael E.; Rogers, Nicole L.

2011-01-01

Falls are a serious health risk for older adults. But for those living in rural and frontier areas of the USA, the risks are higher because of limited access to health care providers and resources. This study employed a community-based participatory research approach to develop a fall prevention toolkit to be used by residents of rural and frontier areas without the assistance of health care providers. Qualitative data were gathered from both key informant interviews and focus groups with a broad range of participants. Data analysis revealed that to be effective and accepted, the toolkit should be not only evidence based but also practical, low-cost, self-explanatory, and usable without the assistance of a health care provider. Materials must be engaging, visually interesting, empowering, sensitive to reading level, and appropriate for low-vision users. These findings should be useful to other researchers developing education and awareness materials for older adults in rural areas. PMID:21941655

Falls amongst older people in Southeast Asia: a scoping review.

PubMed

Romli, M H; Tan, M P; Mackenzie, L; Lovarini, M; Suttanon, P; Clemson, L

2017-04-01

The older population in the Southeast Asian region is accelerating and is expected to surpass the proportion of the ageing population in North America and Europe in the future. This study aims to identify the research literature related to falls among older people in Southeast Asia, to examine current practice and discuss the future direction on falls prevention and interventions in the region. A scoping review design was used. A systematic literature search was conducted using the Medline, CINAHL, AMED, Ageline, PsycINFO, Web of Sciences, Scopus, Thai-Journal Citation Index, MyCite and trial registries databases. Thirty-seven studies and six study protocols were included, from Thailand, Malaysia, Singapore, Vietnam, Indonesia and the Philippines. One-sixth of the studies involved interventions, while the remainder were observational studies. The observational studies mainly determined the falls risk factors. The intervention studies comprised multifactorial interventions and single interventions such as exercises, educational materials and visual correction. Many of the studies replicated international studies and may not have taken into account features unique to Southeast Asia. Our review has revealed studies evaluating falls and management of falls in the Southeast Asian context. More research is required from all Southeast Asian countries to prepare for the future challenges of managing falls as the population ages. Copyright © 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Relationship between fear of falling and outcomes of an inpatient geriatric rehabilitation population--fear of the fear of falling.

PubMed

Denkinger, Michael D; Igl, Wilmar; Lukas, Albert; Bader, Anne; Bailer, Stefanie; Franke, Sebastian; Denkinger, Claudia M; Nikolaus, Thorsten; Jamour, Michael

2010-04-01

To examine the effects of various risk factors on three functional outcomes during rehabilitation. Geriatric inpatient rehabilitation unit. Observational longitudinal study. One hundred sixty-one geriatric rehabilitation inpatients (men, women), mean age 82, who were capable of walking at baseline. Functional status was assessed weekly between admission and discharge and at a follow-up 4 months later at home using the function component of the Short Form-Late Life Function and Disability Instrument, the Barthel Index, and Habitual Gait Speed. Various risk factors, such as falls-related self-efficacy (Falls Efficacy Scale-International), were measured. Associations between predictors and functional status at discharge and follow-up were analyzed using linear regression models and bivariate plots. Fear of falling predicted functioning across all outcomes except for habitual gait speed at discharge and follow-up. Visual comparison of functional trajectories between subgroups confirmed these findings, with different levels of fear of falling across time in linear plots. Thus, superior ability of this measure to discriminate between functional status at baseline across all outcomes and to discriminate between functional change especially with regard to the performance-based outcome was demonstrated. Falls-related self-efficacy is the only parameter that significantly predicts rehabilitation outcome at discharge and follow-up across all outcomes. Therefore, it should be routinely assessed in future studies in (geriatric) rehabilitation and considered to be an important treatment goal.

Characteristics and fall experiences of older adults with and without fear of falling outdoors.

PubMed

Chippendale, Tracy; Lee, Chang Dae

2018-06-01

Using a theoretical model that combines an ecological perspective and Bandura's theory of self-efficacy as a guide, we sought to compare experiences and characteristics of community dwelling older adults with and without concern about falling outdoors. A survey of randomly selected community dwelling older adults across NYC (N = 120) was conducted using the outdoor falls questionnaire. Descriptive quantitative analyses of participant characteristics were conducted for all participants and for those with and without concern about falling outside. Conventional content analysis using two coders was employed to examine outdoor fall experiences for each group. A mixed methods matrix was used to integrate qualitative and quantitative findings. Some participant characteristics were more common among those with a concern about falling outside such as decreased functional status, female gender, and number of prior outdoor falls. As per descriptions of outdoor fall experiences, participants with concern were more likely to report a fall while climbing stairs or stepping up a curb, describe an intrinsic factor as a cause of their fall, use an injury prevention strategy during the fall, sustain a moderate to severe injury, seek medical attention, have had an ambulance called, require help to get up, and describe implementation of a behavioral change after the fall. Differences exist in participant characteristics and outdoor fall experiences of those with and without concern about falling outside. The proposed model can be used to understand fear of falling outdoors and can help to inform the target population and content of intervention programs.

The Microgravity Demonstrator.

ERIC Educational Resources Information Center

Rogers, Melissa J. B.; Wargo, Michael J.

The Microgravity Demonstrator is a tool used to create microgravity conditions in the classroom. A series of demonstrations is used to provide a dramatically visual, physical connection between free-fall and microgravity conditions in order to understand why various types of experiments are performed under microgravity conditions. The manual is…

Use of Aerial Photography to Monitor Fall Chinook Salmon Spawning in the Columbia River

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

Visser, Richard H.; Dauble, Dennis D.; Geist, David R.

2002-11-01

This paper compares two methods for enumerating salmon redds and their application to monitoring spawning activity. Aerial photographs of fall chinook salmon spawning areas in the Hanford Reach of the Columbia River were digitized and mapped using Geographic Information Systems (GIS) techniques in 1994 and 1995 as part of an annual assessment of the population. The number of visible redds from these photographs were compared to counts obtained from visual surveys with fixed wing aircraft. The proportion of the total redds within each of five general survey areas was similar for the two monitoring techniques. However, the total number ofmore » redds based on aerial photographs was 2.2 and 3.0 times higher than those observed during visual surveys for 1994 and 1995, respectively. The divergence in redd counts was most evident near peak spawning activity when the number of redds within individual spawning clusters exceeded 500. Aerial photography improved our ability to monitor numbers of visible salmon redds and to quantify habitat use.« less

Compensatory Postural Adjustments in an Oculus Virtual Reality Environment and the Risk of Falling in Alzheimer's Disease.

PubMed

Gago, Miguel F; Yelshyna, Darya; Bicho, Estela; Silva, Hélder David; Rocha, Luís; Lurdes Rodrigues, Maria; Sousa, Nuno

2016-01-01

Alzheimer's disease (AD) patients have an impaired ability to quickly reweight central sensory dependence in response to unexpected body perturbations. Herein, we aim to study provoked compensatory postural adjustments (CPAs) in a conflicting sensory paradigm with unpredictable visual displacements using virtual reality goggles. We used kinematic time-frequency analyses of two frequency bands: a low-frequency band (LB; 0.3-1.5 Hz; mechanical strategy) and a high-frequency band (HB; 1.5-3.5 Hz; cognitive strategy). We enrolled 19 healthy subjects (controls) and 21 AD patients, divided according to their previous history of falls. The AD faller group presented higher-power LB CPAs, reflecting their worse inherent postural stability. The AD patients had a time lag in their HB CPA reaction. The slower reaction by CPA in AD may be a reflection of different cognitive resources including body schema self-perception, visual motion, depth perception, or a different state of fear and/or anxiety.

Compensatory Postural Adjustments in an Oculus Virtual Reality Environment and the Risk of Falling in Alzheimer's Disease

PubMed Central

Gago, Miguel F.; Yelshyna, Darya; Bicho, Estela; Silva, Hélder David; Rocha, Luís; Lurdes Rodrigues, Maria; Sousa, Nuno

2016-01-01

Background/Aims Alzheimer's disease (AD) patients have an impaired ability to quickly reweight central sensory dependence in response to unexpected body perturbations. Herein, we aim to study provoked compensatory postural adjustments (CPAs) in a conflicting sensory paradigm with unpredictable visual displacements using virtual reality goggles. Methods We used kinematic time-frequency analyses of two frequency bands: a low-frequency band (LB; 0.3-1.5 Hz; mechanical strategy) and a high-frequency band (HB; 1.5-3.5 Hz; cognitive strategy). We enrolled 19 healthy subjects (controls) and 21 AD patients, divided according to their previous history of falls. Results The AD faller group presented higher-power LB CPAs, reflecting their worse inherent postural stability. The AD patients had a time lag in their HB CPA reaction. Conclusion The slower reaction by CPA in AD may be a reflection of different cognitive resources including body schema self-perception, visual motion, depth perception, or a different state of fear and/or anxiety. PMID:27489559

Bleachorexia-an addictive behavior to tooth bleaching: a case report.

PubMed

Lee, Denzel Kun-Tsung; Kastl, Cameron; Chan, Daniel C N

2018-05-01

Bleachorexia, addiction to tooth bleaching, is a behavioral disorder similar to anorexia. The patient feels that their teeth are always not white enough and continues to use whiteners to obtain a "perfect" smile. Such behavior falls under the category of a body dysmorphic disorder and may need medical counseling.

Mediation Analysis of Mode Deactivation Therapy (Reanalysis and Interpretation)

ERIC Educational Resources Information Center

Bass, Christopher K.; Apsche, Jack A.

2013-01-01

A key component of Mode Deactivation Therapy (MDT) is the development of self-awareness and regulatory skills by the client with the aim of helping adolescent males with conduct disordered behaviors, including sexually inappropriate behaviors and emotional dysregulation. The goal includes altering specific behaviors to fall within socially…

Risk of falls in Brazilian elders with and without low back pain assessed using the Physiological Profile Assessment: BACE study

PubMed Central

Rosa, Nayza M. B.; Queiroz, Bárbara Z.; Lopes, Renata A.; Sampaio, Natalia R.; Pereira, Daniele S.; Pereira, Leani S. M.

2016-01-01

ABSTRACT Background Low back pain (LBP) is a common musculoskeletal condition among elders and is associated with falls. However, the underlying biological risk factors for falling among elders with LBP has been poorly investigated. The Physiological Profile Assessment (PPA) is a validated fall-risk assessment tool that involves the direct assessment of sensorimotor abilities and may contribute to the understanding of risk factors for falls among elders with LBP. Objective To assess fall risk using the PPA in elders with and without LBP. Method This is an observational, comparative, cross-sectional study with elders aged ≥65 years. The present study was conducted with a subsample of participants from the Back Complaints in the Elders (BACE) - Brazil study. Fall risk was assessed using the PPA, which contains five tests: visual contrast sensitivity, hand reaction time, quadriceps strength, lower limb proprioception, and postural sway. Results Study participants included 104 individuals with average age of 72.3 (SD=4.0) years, divided into two groups: GI) 52 participants with LBP; GII) 52 participants without LBP. The participants with LBP had a significantly higher fall risk (1.10 95% CI 0.72 to 1.48), greater postural sway (49.78 95% CI 13.54 to 86.01), longer reaction time (58.95 95% CI 33.24 to 84.65), and lower quadriceps strength (–4.42 95% CI –8.24 to –0.59) compared to asymptomatic participants. There was no significant difference for vision and proprioception tests between LBP and non-LBP participants. Conclusion Elders with LBP have greater risk for falls than those without LBP. Our results suggest fall-risk screening may be sensible in elders with LBP. PMID:27683833

[Development of a portable fall risk index for elderly people living in the community].

PubMed

Toba, Kenji; Okochi, Jiro; Takahashi, Tai; Matsubayashi, Kozo; Nishinaga, Masanori; Yamada, Shizuru; Takahashi, Ryutaro; Nishijima, Reiko; Kobayashi, Yoshio; Machida, Ayako; Akishita, Masahiro; Sasaki, Hidetada

2005-05-01

To develop a portable risk index for falls. Risk factors were chosen from previously established factors then we added several environmental factors to the risk index; previous falls in the last 12 month, trippig or stumbling, inability to ascend or descend stairs without help, decreased walking speed, inability to cross a road within the green signal interval, inability to walk 1km without a break, inability to stand on one leg for 5 seconds (eyes open), using a cane, inability to wring out a towel, dizziness or faintness, stooped or rounded back, knee joint pain, visual disturbance, hearing disturbance, cognitive decline, fear of falling, receiving 5 or more prescribed drugs, sensation of darkness at home, obstacles inside, barrier on the carpet or floor, using steps daily at home, steep slopes around home. The questionnaire sheet was completed by 2,439 community-dwelling elderly subjects (76.3 +/- 7.4 years old). The frequency of each items of fall risk index was compared between fallers (history of fall within one year) and non-fallers. Multiple regression analysis was performed to identify independent risk factors for previous falls. Except barrier, step use and steep slope around home, all items in the fall risk index were more frequent in fallers. Multivariate analysis revealed that tripping or stumbling, inability to cross a road within the green signal interval, dizziness or faintness, obstacles inside, inability to wring out a towel, cane use and knee joint pain were independent risk factors for previous falls. These 7 selected items were further analyzed as predictors. The maximum sum of sensitivity and specificity was reached at the cut-off point of 2/3 (sensitivity 0.65, specificity 0.72) by receiver operating curve. Portable fall risk index is useful for clinical settings to identify high-risk subjects.

Alterations in Cerebral White Matter and Neuropsychology in Patients with Cirrhosis and Falls

PubMed Central

Gómez-Ansón, Beatriz; Román, Eva; Fernández de Bobadilla, Ramón; Pires-Encuentra, Patricia; Díaz-Manera, Jordi; Núñez, Fidel; Martinez-Horta, Saül; Vives-Gilabert, Yolanda; Pagonabarraga, Javier; Kulisevsky, Jaume; Guarner, Carlos; Soriano, Germán

2015-01-01

Background & Aim Falls are frequent in patients with cirrhosis but underlying mechanisms are unknown. The aim was to determine the neuropsychological, neurological and brain alterations using magnetic resonance-diffusion tensor imaging (MR-DTI) in cirrhotic patients with falls. Patients and methods Twelve patients with cirrhosis and falls in the previous year were compared to 9 cirrhotic patients without falls. A comprehensive neuropsychological and neurological evaluation of variables that may predispose to falls included: the Mini-Mental State Examination, Psychometric Hepatic Encephalopathy Score (PHES), Parkinson’s Disease-Cognitive Rating Scale, specific tests to explore various cognitive domains, Unified Parkinson’s Disease Rating Scale to evaluate parkinsonism, scales for ataxia and muscular strength, and electroneurography. High-field MR (3T) including DTI and structural sequences was performed in all patients. Results The main neuropsychological findings were impairment in PHES (p = 0.03), Parkinson’s Disease-Cognitive Rating Scale (p = 0.04) and in executive (p<0.05) and visuospatial-visuoconstructive functions (p<0.05) in patients with falls compared to those without. There were no statistical differences between the two groups in the neurological evaluation or in the visual assessment of MRI. MR-DTI showed alterations in white matter integrity in patients with falls compared to those without falls (p<0.05), with local maxima in the superior longitudinal fasciculus and corticospinal tract. These alterations were independent of PHES as a covariate and correlated with executive dysfunction (p<0.05). Conclusions With the limitation of the small sample size, our results suggest that patients with cirrhosis and falls present alterations in brain white matter tracts related to executive dysfunction. These alterations are independent of PHES impairment. PMID:25793766

Different protocols for analyzing behavior and adaptability in obstacle crossing in Parkinson’s disease

PubMed Central

Mollaei, Nafiseh; Bicho, Estela; Sousa, Nuno; Gago, Miguel Fernandes

2017-01-01

Imbalance and tripping over obstacles as a result of altered gait in older adults, especially in patients with Parkinson’s disease (PD), are one of the most common causes of falls. During obstacle crossing, patients with PD modify their behavior in order to decrease the mechanical demands and enhance dynamic stability. Various descriptions of dynamic traits of gait that have been collected over longer periods, probably better synthesize the underlying structure and pattern of fluctuations in gait and can be more sensitive markers of aging or early neurological dysfunction and increased risk of falls. This confirmation challenges the clinimetric of different protocols and paradigms used for gait analysis up till now, in particular when analyzing obstacle crossing. The authors here present a critical review of current knowledge concerning the interplay between the cognition and gait in aging and PD, emphasizing the differences in gait behavior and adaptability while walking over different and challenging obstacle paradigms, and the implications of obstacle negotiation as a predictor of falls. Some evidence concerning the effectiveness of future rehabilitation protocols on reviving obstacle crossing behavior by trial and error relearning, taking advantage of dual-task paradigms, physical exercise, and virtual reality have been put forward in this article. PMID:29158667

Reduced vision selectively impairs spatial updating in fall-prone older adults.

PubMed

Barrett, Maeve M; Doheny, Emer P; Setti, Annalisa; Maguinness, Corrina; Foran, Timothy G; Kenny, Rose Anne; Newell, Fiona N

2013-01-01

The current study examined the role of vision in spatial updating and its potential contribution to an increased risk of falls in older adults. Spatial updating was assessed using a path integration task in fall-prone and healthy older adults. Specifically, participants conducted a triangle completion task in which they were guided along two sides of a triangular route and were then required to return, unguided, to the starting point. During the task, participants could either clearly view their surroundings (full vision) or visuo-spatial information was reduced by means of translucent goggles (reduced vision). Path integration performance was measured by calculating the distance and angular deviation from the participant's return point relative to the starting point. Gait parameters for the unguided walk were also recorded. We found equivalent performance across groups on all measures in the full vision condition. In contrast, in the reduced vision condition, where participants had to rely on interoceptive cues to spatially update their position, fall-prone older adults made significantly larger distance errors relative to healthy older adults. However, there were no other performance differences between fall-prone and healthy older adults. These findings suggest that fall-prone older adults, compared to healthy older adults, have greater difficulty in reweighting other sensory cues for spatial updating when visual information is unreliable.

Postural stability changes in the elderly with cataract simulation and refractive blur.

PubMed

Anand, Vijay; Buckley, John G; Scally, Andy; Elliott, David B

2003-11-01

To determine the influence of cataractous and refractive blur on postural stability and limb-load asymmetry (LLA) and to establish how postural stability changes with the spatial frequency and contrast of the visual stimulus. Thirteen elderly subjects (mean age, 70.76 +/- 4.14 [SD] years) with no history of falls and normal vision were recruited. Postural stability was determined as the root mean square [RMS] of the center of pressure (COP) signal in the anterior-posterior (A-P) and medial-lateral directions and LLA was determined as the ratio of the average body weight placed on the more-loaded limb to the less-loaded limb, recorded during a 30-second period. Data were collected under normal standing conditions and with somatosensory system input disrupted. Measurements were repeated with four visual targets with high (8 cyc/deg) or low (2 cyc/deg) spatial frequency and high (Weber contrast, approximately 95%) or low (Weber contrast, approximately 25%) contrast. Postural stability was measured under conditions of binocular refractive blur of 0, 1, 2, 4, and 8 D and with cataract simulation. The data were analyzed in a population-averaged linear model. The cataract simulation caused significant increases in postural instability equivalent to that caused by 8-D blur conditions, and its effect was greater when the input from the somatosensory system was disrupted. High spatial frequency targets increased postural instability. Refractive blur, cataract simulation, or eye closure had no effect on LLA. Findings indicate that cataractous and refractive blur increase postural instability, and show why the elderly, many of whom have poor vision along with musculoskeletal and central nervous system degeneration, are at greater risk of falling. Findings also highlight that changes in contrast sensitivity rather than resolution changes are responsible for increasing postural instability. Providing low spatial frequency information in certain environments may be useful in maintaining postural stability. Correcting visual impairment caused by uncorrected refractive error and cataracts could be a useful intervention strategy to help prevent falls and fall-related injuries in the elderly.

Transient visual pathway critical for normal development of primate grasping behavior.

PubMed

Mundinano, Inaki-Carril; Fox, Dylan M; Kwan, William C; Vidaurre, Diego; Teo, Leon; Homman-Ludiye, Jihane; Goodale, Melvyn A; Leopold, David A; Bourne, James A

2018-02-06

An evolutionary hallmark of anthropoid primates, including humans, is the use of vision to guide precise manual movements. These behaviors are reliant on a specialized visual input to the posterior parietal cortex. Here, we show that normal primate reaching-and-grasping behavior depends critically on a visual pathway through the thalamic pulvinar, which is thought to relay information to the middle temporal (MT) area during early life and then swiftly withdraws. Small MRI-guided lesions to a subdivision of the inferior pulvinar subnucleus (PIm) in the infant marmoset monkey led to permanent deficits in reaching-and-grasping behavior in the adult. This functional loss coincided with the abnormal anatomical development of multiple cortical areas responsible for the guidance of actions. Our study reveals that the transient retino-pulvinar-MT pathway underpins the development of visually guided manual behaviors in primates that are crucial for interacting with complex features in the environment.

Quantifying Pilot Visual Attention in Low Visibility Terminal Operations

NASA Technical Reports Server (NTRS)

Ellis, Kyle K.; Arthur, J. J.; Latorella, Kara A.; Kramer, Lynda J.; Shelton, Kevin J.; Norman, Robert M.; Prinzel, Lawrence J.

2012-01-01

Quantifying pilot visual behavior allows researchers to determine not only where a pilot is looking and when, but holds implications for specific behavioral tracking when these data are coupled with flight technical performance. Remote eye tracking systems have been integrated into simulators at NASA Langley with effectively no impact on the pilot environment. This paper discusses the installation and use of a remote eye tracking system. The data collection techniques from a complex human-in-the-loop (HITL) research experiment are discussed; especially, the data reduction algorithms and logic to transform raw eye tracking data into quantified visual behavior metrics, and analysis methods to interpret visual behavior. The findings suggest superior performance for Head-Up Display (HUD) and improved attentional behavior for Head-Down Display (HDD) implementations of Synthetic Vision System (SVS) technologies for low visibility terminal area operations. Keywords: eye tracking, flight deck, NextGen, human machine interface, aviation

Disruptions of network connectivity predict impairment in multiple behavioral domains after stroke

PubMed Central

Ramsey, Lenny E.; Metcalf, Nicholas V.; Chacko, Ravi V.; Weinberger, Kilian; Baldassarre, Antonello; Hacker, Carl D.; Shulman, Gordon L.; Corbetta, Maurizio

2016-01-01

Deficits following stroke are classically attributed to focal damage, but recent evidence suggests a key role of distributed brain network disruption. We measured resting functional connectivity (FC), lesion topography, and behavior in multiple domains (attention, visual memory, verbal memory, language, motor, and visual) in a cohort of 132 stroke patients, and used machine-learning models to predict neurological impairment in individual subjects. We found that visual memory and verbal memory were better predicted by FC, whereas visual and motor impairments were better predicted by lesion topography. Attention and language deficits were well predicted by both. Next, we identified a general pattern of physiological network dysfunction consisting of decrease of interhemispheric integration and intrahemispheric segregation, which strongly related to behavioral impairment in multiple domains. Network-specific patterns of dysfunction predicted specific behavioral deficits, and loss of interhemispheric communication across a set of regions was associated with impairment across multiple behavioral domains. These results link key organizational features of brain networks to brain–behavior relationships in stroke. PMID:27402738

Animal Preparations to Assess Neurophysiological Effects of Bio-Dynamic Environments.

DTIC Science & Technology

1980-07-17

deprivation in preventing the acquisition of visually-guided behaviors. The next study examined acquisition of visually-guided behaviors in six animals...Maffei, L. and Bisti, S. Binocular interaction in strabismic kittens deprived of vision. Science, 191, 579-580, 1976. Matin, L. A possible hybrid...function in cat visual cortex following prolonged deprivation . Exp. Brain Res., 25 (1976) 139-156. Hein, A. Visually controlled components of movement

[Formed visual hallucination after excision of the right temporo parietal cystic meningioma--a case report].

PubMed

Yoshimura, Masaki; Uchiyama, Yoshinori; Kaneko, Akira; Hayashi, Noriko; Yamanaka, Kazuhiro; Iwai, Yoshiyasu

2010-08-01

We report the case of a 64-year-old woman with cystic meningioma; this patients was otherwise healthy and experienced formed visual hallucinations after excision of the tumor. She experienced diplopia associated with metamorphopsia, which had persisted for 5 years only when she laid down and turned on her left side. After the excision of the convexity meningioma located in the right temporoparietal lobe, she experienced several types of formed visual hallucinations such as closet-like pictures, flowers sketched on stones, falling maple-like leaves, and moving or wriggling dwarves. She was alert and her visual field was normal; further, she did not experience delirium or seizures. She experienced these hallucinations only when she closed her eyes; these hallucinations persisted for 3 days after the operation. The patient illustrated her observations with beautiful sketches, and the mechanism of visual hallucinations was studied.

Visually Impaired OLder people's Exercise programme for falls prevenTion (VIOLET): a feasibility study protocol

PubMed Central

Skelton, Dawn A; Bailey, Cathy; Howel, Denise; Cattan, Mima; Deary, Vincent; Coe, Dot; de Jong, Lex D; Gawler, Sheena; Gray, Joanne; Lampitt, Rosy; Wilkinson, Jennifer; Adams, Nicola

2016-01-01

Introduction In the UK, 1 in 5 people aged 75 and over live with sight loss. Visually impaired older people (VIOP) have an above average incidence of falls and 1.3–1.9 times more likely to experience hip fractures, than the general population. Older people with eye diseases are ∼3 times more likely than those with good vision, to limit activities due to fear of falling. This feasibility study aims to adapt the group-based Falls Management Exercise (FaME) programme to the needs of VIOP and carry out an external pilot trial to inform the design of a future definitive randomised controlled trial. Methods and design A UK based 2-centre mixed methods, randomised, feasibility study will be conducted over 28 months. Stakeholder panels, including VIOP, will make recommendations for adaptations to an existing exercise programme (FaME), to meet the needs of VIOP, promoting uptake and adherence, while retaining required effective components of the exercise programme. 80 VIOP aged 60 and over, living at home, ambulant with or without a walking aid, will be recruited in Newcastle (n=40) and Glasgow (n=40) through National Health Service (NHS) Trusts and third sector partners. Participants randomised into the intervention arm will receive the adapted FaME programme. Participants randomised into the control arm will continue with usual activity. Outcomes are, recruitment rate, adherence and validated measures including fear of falling and quality of life. Postintervention in-depth qualitative interviews will be conducted with a purposive sample of VIOP (N=10). Postural stability instructors will be interviewed, before trial-specific training and following the intervention. Ethics and dissemination Ethics approval was secured through the National Research Ethics Service (NRES) Committee North East, Newcastle and North Tyneside 2. Glasgow Caledonian University was approved as a non-NHS site with local ethics approval. Findings will be disseminated through peer-reviewed journals, national and international conferences. Trial registration number ISRCTN16949845. PMID:27486124

Correction of Refractive Errors in Rhesus Macaques (Macaca mulatta) Involved in Visual Research

PubMed Central

Mitchell, Jude F; Boisvert, Chantal J; Reuter, Jon D; Reynolds, John H; Leblanc, Mathias

2014-01-01

Macaques are the most common animal model for studies in vision research, and due to their high value as research subjects, often continue to participate in studies well into old age. As is true in humans, visual acuity in macaques is susceptible to refractive errors. Here we report a case study in which an aged macaque demonstrated clear impairment in visual acuity according to performance on a demanding behavioral task. Refraction demonstrated bilateral myopia that significantly affected behavioral and visual tasks. Using corrective lenses, we were able to restore visual acuity. After correction of myopia, the macaque's performance on behavioral tasks was comparable to that of a healthy control. We screened 20 other male macaques to assess the incidence of refractive errors and ocular pathologies in a larger population. Hyperopia was the most frequent ametropia but was mild in all cases. A second macaque had mild myopia and astigmatism in one eye. There were no other pathologies observed on ocular examination. We developed a simple behavioral task that visual research laboratories could use to test visual acuity in macaques. The test was reliable and easily learned by the animals in 1 d. This case study stresses the importance of screening macaques involved in visual science for refractive errors and ocular pathologies to ensure the quality of research; we also provide simple methodology for screening visual acuity in these animals. PMID:25427343

Correction of refractive errors in rhesus macaques (Macaca mulatta) involved in visual research.

PubMed

Mitchell, Jude F; Boisvert, Chantal J; Reuter, Jon D; Reynolds, John H; Leblanc, Mathias

2014-08-01

Macaques are the most common animal model for studies in vision research, and due to their high value as research subjects, often continue to participate in studies well into old age. As is true in humans, visual acuity in macaques is susceptible to refractive errors. Here we report a case study in which an aged macaque demonstrated clear impairment in visual acuity according to performance on a demanding behavioral task. Refraction demonstrated bilateral myopia that significantly affected behavioral and visual tasks. Using corrective lenses, we were able to restore visual acuity. After correction of myopia, the macaque's performance on behavioral tasks was comparable to that of a healthy control. We screened 20 other male macaques to assess the incidence of refractive errors and ocular pathologies in a larger population. Hyperopia was the most frequent ametropia but was mild in all cases. A second macaque had mild myopia and astigmatism in one eye. There were no other pathologies observed on ocular examination. We developed a simple behavioral task that visual research laboratories could use to test visual acuity in macaques. The test was reliable and easily learned by the animals in 1 d. This case study stresses the importance of screening macaques involved in visual science for refractive errors and ocular pathologies to ensure the quality of research; we also provide simple methodology for screening visual acuity in these animals.

Experience-enabled enhancement of adult visual cortex function.

PubMed

Tschetter, Wayne W; Alam, Nazia M; Yee, Christopher W; Gorz, Mario; Douglas, Robert M; Sagdullaev, Botir; Prusky, Glen T

2013-03-20

We previously reported in adult mice that visuomotor experience during monocular deprivation (MD) augmented enhancement of visual-cortex-dependent behavior through the non-deprived eye (NDE) during deprivation, and enabled enhanced function to persist after MD. We investigated the physiological substrates of this experience-enabled form of adult cortical plasticity by measuring visual behavior and visually evoked potentials (VEPs) in binocular visual cortex of the same mice before, during, and after MD. MD on its own potentiated VEPs contralateral to the NDE during MD and shifted ocular dominance (OD) in favor of the NDE in both hemispheres. Whereas we expected visuomotor experience during MD to augment these effects, instead enhanced responses contralateral to the NDE, and the OD shift ipsilateral to the NDE were attenuated. However, in the same animals, we measured NMDA receptor-dependent VEP potentiation ipsilateral to the NDE during MD, which persisted after MD. The results indicate that visuomotor experience during adult MD leads to enduring enhancement of behavioral function, not simply by amplifying MD-induced changes in cortical OD, but through an independent process of increasing NDE drive in ipsilateral visual cortex. Because the plasticity is resident in the mature visual cortex and selectively effects gain of visual behavior through experiential means, it may have the therapeutic potential to target and non-invasively treat eye- or visual-field-specific cortical impairment.

Behavior analysis for elderly care using a network of low-resolution visual sensors

NASA Astrophysics Data System (ADS)

Eldib, Mohamed; Deboeverie, Francis; Philips, Wilfried; Aghajan, Hamid

2016-07-01

Recent advancements in visual sensor technologies have made behavior analysis practical for in-home monitoring systems. The current in-home monitoring systems face several challenges: (1) visual sensor calibration is a difficult task and not practical in real-life because of the need for recalibration when the visual sensors are moved accidentally by a caregiver or the senior citizen, (2) privacy concerns, and (3) the high hardware installation cost. We propose to use a network of cheap low-resolution visual sensors (30×30 pixels) for long-term behavior analysis. The behavior analysis starts by visual feature selection based on foreground/background detection to track the motion level in each visual sensor. Then a hidden Markov model (HMM) is used to estimate the user's locations without calibration. Finally, an activity discovery approach is proposed using spatial and temporal contexts. We performed experiments on 10 months of real-life data. We show that the HMM approach outperforms the k-nearest neighbor classifier against ground truth for 30 days. Our framework is able to discover 13 activities of daily livings (ADL parameters). More specifically, we analyze mobility patterns and some of the key ADL parameters to detect increasing or decreasing health conditions.

Visual rehabilitation: visual scanning, multisensory stimulation and vision restoration trainings

PubMed Central

Dundon, Neil M.; Bertini, Caterina; Làdavas, Elisabetta; Sabel, Bernhard A.; Gall, Carolin

2015-01-01

Neuropsychological training methods of visual rehabilitation for homonymous vision loss caused by postchiasmatic damage fall into two fundamental paradigms: “compensation” and “restoration”. Existing methods can be classified into three groups: Visual Scanning Training (VST), Audio-Visual Scanning Training (AViST) and Vision Restoration Training (VRT). VST and AViST aim at compensating vision loss by training eye scanning movements, whereas VRT aims at improving lost vision by activating residual visual functions by training light detection and discrimination of visual stimuli. This review discusses the rationale underlying these paradigms and summarizes the available evidence with respect to treatment efficacy. The issues raised in our review should help guide clinical care and stimulate new ideas for future research uncovering the underlying neural correlates of the different treatment paradigms. We propose that both local “within-system” interactions (i.e., relying on plasticity within peri-lesional spared tissue) and changes in more global “between-system” networks (i.e., recruiting alternative visual pathways) contribute to both vision restoration and compensatory rehabilitation, which ultimately have implications for the rehabilitation of cognitive functions. PMID:26283935

The K9 On-Board Rover Architecture

NASA Technical Reports Server (NTRS)

Bresina, John L.; Bualat, Maria; Fair, Michael; Washington, Richard; Wright, Anne

2006-01-01

This paper describes the software architecture of NASA Ames Research Center s K9 rover. The goal of the onboard software architecture team was to develop a modular, flexible framework that would allow both high- and low-level control of the K9 hardware. Examples of low-level control are the simple drive or pan/tilt commands which are handled by the resource managers, and examples of high-level control are the command sequences which are handled by the conditional executive. In between these two control levels are complex behavioral commands which are handled by the pilot, such as drive to goal with obstacle avoidance or visually servo to a target. This paper presents the design of the architecture as of Fall 2000. We describe the state of the architecture implementation as well as its current evolution. An early version of the architecture was used for K9 operations during a dual-rover field experiment conducted by NASA Ames Research Center (ARC) and the Jet Propulsion Laboratory (JPL) from May 14 to May 16, 2000.

Effects of Visual Information on Wind-Evoked Escape Behavior of the Cricket, Gryllus bimaculatus.

PubMed

Kanou, Masamichi; Matsuyama, Akane; Takuwa, Hiroyuki

2014-09-01

We investigated the effects of visual information on wind-evoked escape behavior in the cricket, Gryllus bimaculatus. Most agitated crickets were found to retreat into a shelter made of cardboard installed in the test arena within a short time. As this behavior was thought to be a type of escape, we confirmed how a visual image of a shelter affected wind-evoked escape behavior. Irrespective of the brightness of the visual background (black or white) or the absence or presence of a shelter, escape jumps were oriented almost 180° opposite to the source of the air puff stimulus. Therefore, the direction of wind-evoked escape depends solely depended on the direction of the stimulus air puff. In contrast, the turning direction of the crickets during the escape was affected by the position of the visual image of the shelter. During the wind-evoked escape jump, most crickets turned in the direction in which a shelter was presented. This behavioral nature is presumably necessary for crickets to retreat into a shelter within a short time after their escape jump.

The neural basis of visual behaviors in the larval zebrafish.

PubMed

Portugues, Ruben; Engert, Florian

2009-12-01

We review visually guided behaviors in larval zebrafish and summarise what is known about the neural processing that results in these behaviors, paying particular attention to the progress made in the last 2 years. Using the examples of the optokinetic reflex, the optomotor response, prey tracking and the visual startle response, we illustrate how the larval zebrafish presents us with a very promising model vertebrate system that allows neurocientists to integrate functional and behavioral studies and from which we can expect illuminating insights in the near future. Copyright 2009 Elsevier Ltd. All rights reserved.

A conditioned visual orientation requires the ellipsoid body in Drosophila

PubMed Central

Guo, Chao; Du, Yifei; Yuan, Deliang; Li, Meixia; Gong, Haiyun; Gong, Zhefeng

2015-01-01

Orientation, the spatial organization of animal behavior, is an essential faculty of animals. Bacteria and lower animals such as insects exhibit taxis, innate orientation behavior, directly toward or away from a directional cue. Organisms can also orient themselves at a specific angle relative to the cues. In this study, using Drosophila as a model system, we established a visual orientation conditioning paradigm based on a flight simulator in which a stationary flying fly could control the rotation of a visual object. By coupling aversive heat shocks to a fly's orientation toward one side of the visual object, we found that the fly could be conditioned to orientate toward the left or right side of the frontal visual object and retain this conditioned visual orientation. The lower and upper visual fields have different roles in conditioned visual orientation. Transfer experiments showed that conditioned visual orientation could generalize between visual targets of different sizes, compactness, or vertical positions, but not of contour orientation. Rut—Type I adenylyl cyclase and Dnc—phosphodiesterase were dispensable for visual orientation conditioning. Normal activity and scb signaling in R3/R4d neurons of the ellipsoid body were required for visual orientation conditioning. Our studies established a visual orientation conditioning paradigm and examined the behavioral properties and neural circuitry of visual orientation, an important component of the insect's spatial navigation. PMID:25512578

Visual search for object categories is predicted by the representational architecture of high-level visual cortex

PubMed Central

Alvarez, George A.; Nakayama, Ken; Konkle, Talia

2016-01-01

Visual search is a ubiquitous visual behavior, and efficient search is essential for survival. Different cognitive models have explained the speed and accuracy of search based either on the dynamics of attention or on similarity of item representations. Here, we examined the extent to which performance on a visual search task can be predicted from the stable representational architecture of the visual system, independent of attentional dynamics. Participants performed a visual search task with 28 conditions reflecting different pairs of categories (e.g., searching for a face among cars, body among hammers, etc.). The time it took participants to find the target item varied as a function of category combination. In a separate group of participants, we measured the neural responses to these object categories when items were presented in isolation. Using representational similarity analysis, we then examined whether the similarity of neural responses across different subdivisions of the visual system had the requisite structure needed to predict visual search performance. Overall, we found strong brain/behavior correlations across most of the higher-level visual system, including both the ventral and dorsal pathways when considering both macroscale sectors as well as smaller mesoscale regions. These results suggest that visual search for real-world object categories is well predicted by the stable, task-independent architecture of the visual system. NEW & NOTEWORTHY Here, we ask which neural regions have neural response patterns that correlate with behavioral performance in a visual processing task. We found that the representational structure across all of high-level visual cortex has the requisite structure to predict behavior. Furthermore, when directly comparing different neural regions, we found that they all had highly similar category-level representational structures. These results point to a ubiquitous and uniform representational structure in high-level visual cortex underlying visual object processing. PMID:27832600

Factors Related to Impaired Visual Orienting Behavior in Children with Intellectual Disabilities

ERIC Educational Resources Information Center

Boot, F. H.; Pel, J .J. M.; Evenhuis, H. M.; van der Steen, J.

2012-01-01

It is generally assumed that children with intellectual disabilities (ID) have an increased risk of impaired visual information processing due to brain damage or brain development disorder. So far little evidence has been presented to support this assumption. Abnormal visual orienting behavior is a sensitive tool to evaluate impaired visual…

Embedding Multilevel Survival Analysis of Dyadic Social Interaction in Structural Equation Models: Hazard Rates as Both Outcomes and Predictors

PubMed Central

Snyder, James

2014-01-01

Objective Demonstrate multivariate multilevel survival analysis within a larger structural equation model. Test the 3 hypotheses that when confronted by a negative parent, child rates of angry, sad/fearful, and positive emotion will increase, decrease, and stay the same, respectively, for antisocial compared with normal children. This same pattern will predict increases in future antisocial behavior. Methods Parent–child dyads were videotaped in the fall of kindergarten in the laboratory and antisocial behavior ratings were obtained in the fall of kindergarten and third grade. Results Kindergarten antisocial predicted less child sad/fear and child positive but did not predict child anger given parent negative. Less child positive and more child neutral given parent negative predicted increases in third-grade antisocial behavior. Conclusions The model is a useful analytic tool for studying rates of social behavior. Lack of positive affect or excess neutral affect may be a new risk factor for child antisocial behavior. PMID:24133296

Ontogeny and Sexual Differences in Swimming Proximity to Conspecifics in Response to Visual Cues in Medaka Fish.

PubMed

Isoe, Yasuko; Konagaya, Yumi; Yokoi, Saori; Kubo, Takeo; Takeuchi, Hideaki

2016-06-01

Adult medaka fish (Oryzias latipes) exhibit complex social behaviors that depend mainly on visual cues from conspecifics. The ontogeny of visually-mediated social behaviors from larval/juvenile to adult medaka fish, however, is unknown. In the present study, we established a simple behavioral paradigm to evaluate the swimming proximity to conspecifics based on visual cues in an inter-individual interaction of two medaka fish throughout life. When two fish were placed separately in a cylindrical tank with a concentric transparent wall, the two fish maintained close proximity to each other. A normal fish inside the tank maintained proximity to an optic nerve-cut fish outside of the tank, while the converse was not true. This behavioral paradigm enabled us to quantify visually-induced motivation of a single fish inside the tank. The proximity was detected from larval/juvenile to adult fish. Larval fish, however, maintained close proximity not only to conspecifics, but also to heterospecifics. As the growth stage increased, the degree of proximity to heterospecifics decreased, suggesting that shoaling preferences toward conspecifics and/or visual ability to recognize conspecifics is refined and established according to the growth stage. Furthermore, the proximity of adult female fish was affected by their reproductive status and social familiarity. Only before spawning, adult females maintained closer proximity to familiar males rather than to unfamiliar males, suggesting that proximity was affected by familiarity in a female-specific manner. This simple behavioral paradigm will contribute to our understanding of the neural basis of the development of visually-mediated social behavior using medaka fish.

[Evaluation of visual functions in elderly patients with femoral neck fracture].

PubMed

Oner, Mithat; Oner, Ayşe; Güney, Ahmet; Halici, Mehmet; Arda, Hatice; Bilal, Okkeş

2009-01-01

We aimed at assessing the visual functions in elderly patients with femoral neck fracture and to compare the results with age-matched controls in this three-year prospective study. Seventy-one patients with a history of fall related hip fracture (39 females, 32 males; mean age 76.3+/-9.7 years; range 64 to 90 years) and who were diagnosed with femoral neck fracture after direct graphy were treated by means of bipolar partial prosthesis and they were contacted postoperatively or prior to discharge to participate in the study. Visual acuity, depth perception, the presence of cataract in the red reflex were evaluated. A dilated fundus and slit-lamp examination were performed if possible. On completion of the examination, the ophthalmologist documented the causes of any visual impairment found. Control group was comprised of age-matched 40 subjects (22 females, 18 males; mean age 73.2+/-7.6 years; range 62 to 90 years) who applied to ophtalmology clinic for routine examination. The visual acuity was significantly decreased in the patient group as was stereopsis (p<0.05). We found no difference between the study group and the controls when we evaluate the distribution of self reported eye disease and eye disease found on ocular examination. The rate of cases who reported not usually wearing glasses was 35% while it was 5% in the control group. When we evaluate the time since last examination, 38% of cases had not had an eye examination for over four years, as compared with 22.5% of controls. This study shows that elderly people should have their eyes tested at least once every two years, refractive errors should be corrected and eye diseases should be treated to decrease the risk of fall-related femoral neck fractures.

Falls and age in patients with Alzheimer's disease.

PubMed

Bassiony, Medhat M; Rosenblatt, Adam; Baker, Alva; Steinberg, Martin; Steele, Cynthia D; Sheppard, Jeanie-Marie E; Lyketsos, Constantine G

2004-08-01

The study's objective was to estimate the prevalence of falls in community-residing patients with Alzheimer's disease (AD) and to investigate the relationship between falls and age in AD. This was a study of 326 community-residing patients with AD according to National Institute of Neurological and Communicative Disorders and Stroke and Alzheimer's Disease and Related Disorders Association criteria. The patients and their caregivers were asked about falls, behavioral disturbances, and medication use within the last 2 weeks. The patients were also rated on standardized measures of cognitive impairment, stage of dementia, depression, daily activities, general health, and extrapyramidal symptoms. Falls occurred in 24 (7.4%) patients with AD during the last 2 weeks. Using multiple logistic regression analyses, falls were independently associated with old age (odds ratio = 1.2; p = .03; 95% confidence interval = 1.0 to 1.4) but not with other variables examined. The authors conclude that falls in community-residing patients with AD are significantly associated with old age. Population-based prospective studies are needed to investigate further the risk factors for falls in AD.

[Does the care for the fear of falling bring a profit to community living elderly people who had experienced falls?].

PubMed

Landrot, Marion De Rogalski; Perrot, Catherine; Blanc, Patricia; Beauchet, Olivier; Blanchon, Marie Ange; Gonthier, Régis

2007-09-01

fall is common in old people and has multiple consequences, physical but also psychological, with a fear of falling which results in reduction in the activities of everyday life, loss of autonomy and entry in dependence. The aim of the study was to evluate the benefit of taking into account the fear of falling in the care of old people who had experienced falls. old people who experienced falls and with a good cognitive status were followed in a day hospital during one year. Evaluation including a specific assessment of the responsibility of the psychological factor, the photolangage, was performed before and after multi-field rehabilitation. We used the rating scales ADL, IADL, SF-36, SAFE, and verbal and analogical scales of the fear of falling. fifteen patients were included (mean age 85 years +/- 5,7). The majority were women living alone, with a good nutritional status, a moderated renal insufficiency, and a comorbidity involving polymedication. Scores on the ADL and IADL scales showed a consolidation of the patients' autonomy, with a slight but significant improvement of the IADL scores (p < 0,05). All scales assessing the fear of falling (visual analogical, verbal scales, SAFE) showed a statistically significant improvement (p<0,001). SF-36 scale, exploring the quality of life perceived by the patients, showed a great deterioration immediately after falling, and a statistically significant improvement on seven of the eight subscales after rehabilitation. The global physical score (GCV) was improved in a nonsignificant way, whereas the global psychic score (MCS) progressed in a statistically significant way (p < 0,001). this pilot study shows that multi-field rehabilitation and adapted assumption of responsibility of fear of falling brings a benefit in term of quality of life and preservation of autonomy in old people living in the community who had experienced falls.

Postural stability and history of falls in cognitively able older adults: the Canton Ticino study.

PubMed

Merlo, Andrea; Zemp, Damiano; Zanda, Enrica; Rocchi, Sabrina; Meroni, Fabiano; Tettamanti, Mauro; Recchia, Angela; Lucca, Ugo; Quadri, Pierluigi

2012-09-01

Falls are common events in the elderly and represent the main risk factor for fractures and other injuries. Strategies for fall prevention rely on the multifactorial assessment of the risk of falling. The contribution of instrumented balance assessment to the prediction of falls remains unclear in the literature. In this study, we analyzed the association between the fall-history of a wide sample of older people without dementia and the values of a set of posturographic parameters acquired in different visual, proprioceptive and mental conditions. A consecutive sample of 130 cognitively able elderly subjects, age≥70 years, was analyzed. Based on their fall-history in the last year, subjects were categorized into non-fallers (NF), fallers (F) and recurrent fallers (RF>2 falls). Each subject was assessed by measurements of cognition and functional ability. Static posturography tests were performed in five conditions: with eyes open/close (EO/EC) on a firm/compliant (FS/CS) surface and while performing a cognitive task. The center of pressure (COP) mean position referred to the mid-point of the heels, area of the 95% confidence ellipse, sway mean velocities and RMS displacements in the antero-posterior (AP) and medio-lateral (ML) directions were computed and their association with the fall-history was assessed. The mean position of the COP in the AP direction and the confidence ellipse area were associated with the fall-history in the EOFS, ECFS and EOCS conditions (P<0.05). RMS displacements were also associated with the fall-history in the EOCS condition (P<0.05). Significant group differences (P<0.05) were found in the EOCS conditions, which greatly enhanced the differences among NF, F and RF. The ability to control balance while standing with eyes open on a compliant surface showed a high degree of association with the fall-history of older people with no or mild cognitive impairment. Copyright © 2012 Elsevier B.V. All rights reserved.

Assessing and training standing balance in older adults: a novel approach using the 'Nintendo Wii' Balance Board.

PubMed

Young, William; Ferguson, Stuart; Brault, Sébastien; Craig, Cathy

2011-02-01

Older adults, deemed to be at a high risk of falling, are often unable to participate in dynamic exercises due to physical constraints and/or a fear of falling. Using the Nintendo 'Wii Balance Board' (WBB) (Nintendo, Kyoto, Japan), we have developed an interface that allows a user to accurately calculate a participant's centre of pressure (COP) and incorporate it into a virtual environment to create bespoke diagnostic or training programmes that exploit real-time visual feedback of current COP position. This platform allows researchers to design, control and validate tasks that both train and test balance function. This technology provides a safe, adaptable and low-cost balance training/testing solution for older adults, particularly those at high-risk of falling. Copyright © 2010 Elsevier B.V. All rights reserved.

Learning Science Through Visualization

NASA Technical Reports Server (NTRS)

Chaudhury, S. Raj

2005-01-01

In the context of an introductory physical science course for non-science majors, I have been trying to understand how scientific visualizations of natural phenomena can constructively impact student learning. I have also necessarily been concerned with the instructional and assessment approaches that need to be considered when focusing on learning science through visually rich information sources. The overall project can be broken down into three distinct segments : (i) comparing students' abilities to demonstrate proportional reasoning competency on visual and verbal tasks (ii) decoding and deconstructing visualizations of an object falling under gravity (iii) the role of directed instruction to elicit alternate, valid scientific visualizations of the structure of the solar system. Evidence of student learning was collected in multiple forms for this project - quantitative analysis of student performance on written, graded assessments (tests and quizzes); qualitative analysis of videos of student 'think aloud' sessions. The results indicate that there are significant barriers for non-science majors to succeed in mastering the content of science courses, but with informed approaches to instruction and assessment, these barriers can be overcome.

Correction of wheat meal falling number to a common barometric pressure at simulated laboratory elevations of 0 to 1500 meters

USDA-ARS?s Scientific Manuscript database

Falling number, a procedure that indirectly gauges germination enzyme activity in wheat by its measurement of the viscous behavior of a heated starch-water mixture, is affected by the immersion water bath temperature. Maintained at boiling point, the water bath temperature is determined by barometr...

Variable Acorn Crops: Responses of White-Tailed Deer and Other Mast Consumers

Treesearch

William J. McShea; Georg Schwede

1993-01-01

We examined movements and behavior of female white-tailed deer (Odocoileus virginianus) relative to the acorn mast-fall from 1986 through 1989 in a mature deciduous forest in Front Royal, Virginia. Ten white-tailed deer with radiotransmitters increased their home range to incorporate acorn-producing areas during mast-fall. Consumption of acorns by...

Simulating Visual Attention Allocation of Pilots in an Advanced Cockpit Environment

NASA Technical Reports Server (NTRS)

Frische, F.; Osterloh, J.-P.; Luedtke, A.

2011-01-01

This paper describes the results of experiments conducted with human line pilots and a cognitive pilot model during interaction with a new 40 Flight Management System (FMS). The aim of these experiments was to gather human pilot behavior data in order to calibrate the behavior of the model. Human behavior is mainly triggered by visual perception. Thus, the main aspect was to setup a profile of human pilots' visual attention allocation in a cockpit environment containing the new FMS. We first performed statistical analyses of eye tracker data and then compared our results to common results of familiar analyses in standard cockpit environments. The comparison has shown a significant influence of the new system on the visual performance of human pilots. Further on, analyses of the pilot models' visual performance have been performed. A comparison to human pilots' visual performance revealed important improvement potentials.

Infant Visual Attention and Object Recognition

PubMed Central

Reynolds, Greg D.

2015-01-01

This paper explores the role visual attention plays in the recognition of objects in infancy. Research and theory on the development of infant attention and recognition memory are reviewed in three major sections. The first section reviews some of the major findings and theory emerging from a rich tradition of behavioral research utilizing preferential looking tasks to examine visual attention and recognition memory in infancy. The second section examines research utilizing neural measures of attention and object recognition in infancy as well as research on brain-behavior relations in the early development of attention and recognition memory. The third section addresses potential areas of the brain involved in infant object recognition and visual attention. An integrated synthesis of some of the existing models of the development of visual attention is presented which may account for the observed changes in behavioral and neural measures of visual attention and object recognition that occur across infancy. PMID:25596333

A Falling Corona Model for the Anomalous Behavior of the Broad Emission Lines in NGC 5548

NASA Astrophysics Data System (ADS)

Sun, Mouyuan; Xue, Yongquan; Cai, Zhenyi; Guo, Hengxiao

2018-04-01

NGC 5548 has been intensively monitored by the AGN Space Telescope and Optical Reverberation Mapping collaboration. Approximately after half of the light curves, the correlation between the broad emission lines and the lag-corrected ultraviolet (UV) continua becomes weak. This anomalous behavior is accompanied by an increase of soft X-ray emission. We propose a simple model to understand this anomalous behavior, i.e., the corona might fall down, thereby increasing the covering fraction of the inner disk. Therefore, X-ray and extreme-UV emission suffer from spectral variations. The UV continua variations are driven by both X-ray and extreme-UV variations. Consequently, the spectral variability induced by the falling corona would dilute the correlation between the broad emission lines and the UV continua. Our model can explain many additional observational facts, including the dependence of the anomalous behavior on velocity and ionization energy. We also show that the time lag and correlation between the X-ray and the UV variations change as NGC 5548 displays the anomalous behavior. The time lag is dramatically longer than the expectation from disk reprocessing if the anomalous behavior is properly excluded. During the anomalous state, the time lag approaches the light-travel timescale of disk reprocessing albeit with a much weaker correlation. We speculate that the time lag in the normal state is caused by reprocessing of the broad line region gas. As NGC 5548 enters the abnormal state, the contribution of the broad line region gas is smaller; the time lag reflects disk reprocessing. We also discuss alternative scenarios.

Investigation of the effect of changes in muscle strength in gestational age upon fear of falling and quality of life.

PubMed

Atay, Emrah; Başalan Iz, Fatma

2015-01-01

The aim of this study is the investigation of the effect of changes in muscle strength in gestational age upon fear of falling and quality of life. This longitudinal, descriptive study included a sample of 37 pregnant women who volunteered to participate. The research data were collected at 20 and 32 weeks of gestation. Data collection instruments included a newly developed questionnaire form, the Tinetti Falls Efficacy Scale, a visual analog scale, and the Turkish language version of the WHO Quality of Life Scale. Upper body flexibility was measured by the back scratch test, while muscle strength was measured by a handgrip dynamometer and balance by the unipedal stance test. It was found that, as pregnancy advanced, pregnant women had an increased fear of falling, as well as elevated systolic and diastolic blood pressure levels. Participants suffered significant impairments in their balance, handgrip strength, and quality of life within the physical, psychological, and environmental domains. As pregnancy advances, muscle strength decreases and the fear of falling experienced by pregnant women increases, which significantly impairs the quality of life in the domains of environment, physical, and mental health.

Non-Verbal Communication in Children with Visual Impairment

ERIC Educational Resources Information Center

Mallineni, Sharmila; Nutheti, Rishita; Thangadurai, Shanimole; Thangadurai, Puspha

2006-01-01

The aim of this study was to determine: (a) whether children with visual and additional impairments show any non-verbal behaviors, and if so what were the common behaviors; (b) whether two rehabilitation professionals interpreted the non-verbal behaviors similarly; and (c) whether a speech pathologist and a rehabilitation professional interpreted…

Visual behavior of the Asian Citrus Psyllid Diaphorina citri (Hemiptera: Liviidae)

USDA-ARS?s Scientific Manuscript database

As the vector of the global disease of citrus greening or huanglongbing (HLB), relatively little is known concerning the Asian Citrus Psyllid (ACP) behavior towards visual cues. The objective of this study was to elucidate behavioral responses of ACP towards several colors of light. ACP responded ...

Behavioral Science Design for Audio-Visual Software Development

ERIC Educational Resources Information Center

Foster, Dennis L.

1974-01-01

A discussion of the basic structure of the behavioral audio-visual production which consists of objectives analysis, approach determination, technical production, fulfillment evaluation, program refinement, implementation, and follow-up. (Author)

Modeling and evaluating user behavior in exploratory visual analysis

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

Reda, Khairi; Johnson, Andrew E.; Papka, Michael E.

Empirical evaluation methods for visualizations have traditionally focused on assessing the outcome of the visual analytic process as opposed to characterizing how that process unfolds. There are only a handful of methods that can be used to systematically study how people use visualizations, making it difficult for researchers to capture and characterize the subtlety of cognitive and interaction behaviors users exhibit during visual analysis. To validate and improve visualization design, however, it is important for researchers to be able to assess and understand how users interact with visualization systems under realistic scenarios. This paper presents a methodology for modeling andmore » evaluating the behavior of users in exploratory visual analysis. We model visual exploration using a Markov chain process comprising transitions between mental, interaction, and computational states. These states and the transitions between them can be deduced from a variety of sources, including verbal transcripts, videos and audio recordings, and log files. This model enables the evaluator to characterize the cognitive and computational processes that are essential to insight acquisition in exploratory visual analysis, and reconstruct the dynamics of interaction between the user and the visualization system. We illustrate this model with two exemplar user studies, and demonstrate the qualitative and quantitative analytical tools it affords.« less

Analysis of stated preference survey data for river-crossing travel behavior in the Portland/Vancouver metropolitan area

DOT National Transportation Integrated Search

1997-01-01

The MPO in the Southwest Washington and Oregon initiated a major activity and travel behavior survey from the Spring of 1994 to the Fall 1994, including the Stated Preference survey for river-crossing trip behavior. The purpose of the survey is to ga...

The Association of Peer Behavioral Regulation with School Readiness Skills in Preschool

ERIC Educational Resources Information Center

Rojas, Natalia

2016-01-01

The current study examines classroom-level peer behavioral regulation skills and their implications for children's school readiness outcomes. Specifically, this study will answer the following research questions: (1) Is the average level of peers' behavioral regulation skills in a classroom in the fall associated with growth in children's school…

Parental Social Support and the Physical Activity-Related Behaviors of Youth: A Review

ERIC Educational Resources Information Center

Beets, Michael W.; Cardinal, Bradley J.; Alderman, Brandon L.

2010-01-01

Social support from parents serves as one of the primary influences of youth physical activity-related behaviors. A systematic review was conducted on the relationship of parental social support to the physical activity-related behaviors of youth. Four categories of social support were identified, falling under two distinct mechanisms--tangible…

Simulation and visualization of energy-related occupant behavior in office buildings

DOE PAGES

Chen, Yixing; Liang, Xin; Hong, Tianzhen; ...

2017-03-15

In current building performance simulation programs, occupant presence and interactions with building systems are over-simplified and less indicative of real world scenarios, contributing to the discrepancies between simulated and actual energy use in buildings. Simulation results are normally presented using various types of charts. However, using those charts, it is difficult to visualize and communicate the importance of occupants’ behavior to building energy performance. This study introduced a new approach to simulating and visualizing energy-related occupant behavior in office buildings. First, the Occupancy Simulator was used to simulate the occupant presence and movement and generate occupant schedules for each spacemore » as well as for each occupant. Then an occupant behavior functional mockup unit (obFMU) was used to model occupant behavior and analyze their impact on building energy use through co-simulation with EnergyPlus. Finally, an agent-based model built upon AnyLogic was applied to visualize the simulation results of the occupant movement and interactions with building systems, as well as the related energy performance. A case study using a small office building in Miami, FL was presented to demonstrate the process and application of the Occupancy Simulator, the obFMU and EnergyPlus, and the AnyLogic module in simulation and visualization of energy-related occupant behaviors in office buildings. Furthermore, the presented approach provides a new detailed and visual way for policy makers, architects, engineers and building operators to better understand occupant energy behavior and their impact on energy use in buildings, which can improve the design and operation of low energy buildings.« less

Simulation and visualization of energy-related occupant behavior in office buildings

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

Chen, Yixing; Liang, Xin; Hong, Tianzhen

In current building performance simulation programs, occupant presence and interactions with building systems are over-simplified and less indicative of real world scenarios, contributing to the discrepancies between simulated and actual energy use in buildings. Simulation results are normally presented using various types of charts. However, using those charts, it is difficult to visualize and communicate the importance of occupants’ behavior to building energy performance. This study introduced a new approach to simulating and visualizing energy-related occupant behavior in office buildings. First, the Occupancy Simulator was used to simulate the occupant presence and movement and generate occupant schedules for each spacemore » as well as for each occupant. Then an occupant behavior functional mockup unit (obFMU) was used to model occupant behavior and analyze their impact on building energy use through co-simulation with EnergyPlus. Finally, an agent-based model built upon AnyLogic was applied to visualize the simulation results of the occupant movement and interactions with building systems, as well as the related energy performance. A case study using a small office building in Miami, FL was presented to demonstrate the process and application of the Occupancy Simulator, the obFMU and EnergyPlus, and the AnyLogic module in simulation and visualization of energy-related occupant behaviors in office buildings. Furthermore, the presented approach provides a new detailed and visual way for policy makers, architects, engineers and building operators to better understand occupant energy behavior and their impact on energy use in buildings, which can improve the design and operation of low energy buildings.« less

Vision in laboratory rodents-Tools to measure it and implications for behavioral research.

PubMed

Leinonen, Henri; Tanila, Heikki

2017-07-29

Mice and rats are nocturnal mammals and their vision is specialized for detection of motion and contrast in dim light conditions. These species possess a large proportion of UV-sensitive cones in their retinas and the majority of their optic nerve axons target superior colliculus rather than visual cortex. Therefore, it was a widely held belief that laboratory rodents hardly utilize vision during day-time behavior. This dogma is being questioned as accumulating evidence suggests that laboratory rodents are able to perform complex visual functions, such as perceiving subjective contours, and that declined vision may affect their performance in many behavioral tasks. For instance, genetic engineering may have unexpected consequences on vision as mouse models of Alzheimer's and Huntington's diseases have declined visual function. Rodent vision can be tested in numerous ways using operant training or reflex-based behavioral tasks, or alternatively using electrophysiological recordings. In this article, we will first provide a summary of visual system and explain its characteristics unique to rodents. Then, we present well-established techniques to test rodent vision, with an emphasis on pattern vision: visual water test, optomotor reflex test, pattern electroretinography and pattern visual evoked potentials. Finally, we highlight the importance of visual phenotyping in rodents. As the number of genetically engineered rodent models and volume of behavioral testing increase simultaneously, the possibility of visual dysfunctions needs to be addressed. Neglect in this matter potentially leads to crude biases in the field of neuroscience and beyond. Copyright © 2017 Elsevier B.V. All rights reserved.

Visual motion detection and habitat preference in Anolis lizards.

PubMed

Steinberg, David S; Leal, Manuel

2016-11-01

The perception of visual stimuli has been a major area of inquiry in sensory ecology, and much of this work has focused on coloration. However, for visually oriented organisms, the process of visual motion detection is often equally crucial to survival and reproduction. Despite the importance of motion detection to many organisms' daily activities, the degree of interspecific variation in the perception of visual motion remains largely unexplored. Furthermore, the factors driving this potential variation (e.g., ecology or evolutionary history) along with the effects of such variation on behavior are unknown. We used a behavioral assay under laboratory conditions to quantify the visual motion detection systems of three species of Puerto Rican Anolis lizard that prefer distinct structural habitat types. We then compared our results to data previously collected for anoles from Cuba, Puerto Rico, and Central America. Our findings indicate that general visual motion detection parameters are similar across species, regardless of habitat preference or evolutionary history. We argue that these conserved sensory properties may drive the evolution of visual communication behavior in this clade.

Seasonality directs contrasting food collection behavior and nutrient regulation strategies in ants.

PubMed

Cook, Steven C; Eubanks, Micky D; Gold, Roger E; Behmer, Spencer T

2011-01-01

Long-lived animals, including social insects, often display seasonal shifts in foraging behavior. Foraging is ultimately a nutrient consumption exercise, but the effect of seasonality per se on changes in foraging behavior, particularly as it relates to nutrient regulation, is poorly understood. Here, we show that field-collected fire ant colonies, returned to the laboratory and maintained under identical photoperiod, temperature, and humidity regimes, and presented with experimental foods that had different protein (p) to carbohydrate (c) ratios, practice summer- and fall-specific foraging behaviors with respect to protein-carbohydrate regulation. Summer colonies increased the amount of food collected as the p:c ratio of their food became increasingly imbalanced, but fall colonies collected similar amounts of food regardless of the p:c ratio of their food. Choice experiments revealed that feeding was non-random, and that both fall and summer ants preferred carbohydrate-biased food. However, ants rarely ate all the food they collected, and their cached or discarded food always contained little carbohydrate relative to protein. From a nutrient regulation strategy, ants consumed most of the carbohydrate they collected, but regulated protein consumption to a similar level, regardless of season. We suggest that varied seasonal food collection behaviors and nutrient regulation strategies may be an adaptation that allows long-lived animals to meet current and future nutrient demands when nutrient-rich foods are abundant (e.g. spring and summer), and to conserve energy and be metabolically more efficient when nutritionally balanced foods are less abundant.

Seasonality Directs Contrasting Food Collection Behavior and Nutrient Regulation Strategies in Ants

PubMed Central

Cook, Steven C.; Eubanks, Micky D.; Gold, Roger E.; Behmer, Spencer T.

2011-01-01

Long-lived animals, including social insects, often display seasonal shifts in foraging behavior. Foraging is ultimately a nutrient consumption exercise, but the effect of seasonality per se on changes in foraging behavior, particularly as it relates to nutrient regulation, is poorly understood. Here, we show that field-collected fire ant colonies, returned to the laboratory and maintained under identical photoperiod, temperature, and humidity regimes, and presented with experimental foods that had different protein (p) to carbohydrate (c) ratios, practice summer- and fall-specific foraging behaviors with respect to protein-carbohydrate regulation. Summer colonies increased the amount of food collected as the p:c ratio of their food became increasingly imbalanced, but fall colonies collected similar amounts of food regardless of the p:c ratio of their food. Choice experiments revealed that feeding was non-random, and that both fall and summer ants preferred carbohydrate-biased food. However, ants rarely ate all the food they collected, and their cached or discarded food always contained little carbohydrate relative to protein. From a nutrient regulation strategy, ants consumed most of the carbohydrate they collected, but regulated protein consumption to a similar level, regardless of season. We suggest that varied seasonal food collection behaviors and nutrient regulation strategies may be an adaptation that allows long-lived animals to meet current and future nutrient demands when nutrient-rich foods are abundant (e.g. spring and summer), and to conserve energy and be metabolically more efficient when nutritionally balanced foods are less abundant. PMID:21966522

LoyalTracker: Visualizing Loyalty Dynamics in Search Engines.

PubMed

Shi, Conglei; Wu, Yingcai; Liu, Shixia; Zhou, Hong; Qu, Huamin

2014-12-01

The huge amount of user log data collected by search engine providers creates new opportunities to understand user loyalty and defection behavior at an unprecedented scale. However, this also poses a great challenge to analyze the behavior and glean insights into the complex, large data. In this paper, we introduce LoyalTracker, a visual analytics system to track user loyalty and switching behavior towards multiple search engines from the vast amount of user log data. We propose a new interactive visualization technique (flow view) based on a flow metaphor, which conveys a proper visual summary of the dynamics of user loyalty of thousands of users over time. Two other visualization techniques, a density map and a word cloud, are integrated to enable analysts to gain further insights into the patterns identified by the flow view. Case studies and the interview with domain experts are conducted to demonstrate the usefulness of our technique in understanding user loyalty and switching behavior in search engines.

Real-Time Visualization of Network Behaviors for Situational Awareness

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

Best, Daniel M.; Bohn, Shawn J.; Love, Douglas V.

Plentiful, complex, and dynamic data make understanding the state of an enterprise network difficult. Although visualization can help analysts understand baseline behaviors in network traffic and identify off-normal events, visual analysis systems often do not scale well to operational data volumes (in the hundreds of millions to billions of transactions per day) nor to analysis of emergent trends in real-time data. We present a system that combines multiple, complementary visualization techniques coupled with in-stream analytics, behavioral modeling of network actors, and a high-throughput processing platform called MeDICi. This system provides situational understanding of real-time network activity to help analysts takemore » proactive response steps. We have developed these techniques using requirements gathered from the government users for which the tools are being developed. By linking multiple visualization tools to a streaming analytic pipeline, and designing each tool to support a particular kind of analysis (from high-level awareness to detailed investigation), analysts can understand the behavior of a network across multiple levels of abstraction.« less

Learning Enhances Sensory and Multiple Non-sensory Representations in Primary Visual Cortex

PubMed Central

Poort, Jasper; Khan, Adil G.; Pachitariu, Marius; Nemri, Abdellatif; Orsolic, Ivana; Krupic, Julija; Bauza, Marius; Sahani, Maneesh; Keller, Georg B.; Mrsic-Flogel, Thomas D.; Hofer, Sonja B.

2015-01-01

Summary We determined how learning modifies neural representations in primary visual cortex (V1) during acquisition of a visually guided behavioral task. We imaged the activity of the same layer 2/3 neuronal populations as mice learned to discriminate two visual patterns while running through a virtual corridor, where one pattern was rewarded. Improvements in behavioral performance were closely associated with increasingly distinguishable population-level representations of task-relevant stimuli, as a result of stabilization of existing and recruitment of new neurons selective for these stimuli. These effects correlated with the appearance of multiple task-dependent signals during learning: those that increased neuronal selectivity across the population when expert animals engaged in the task, and those reflecting anticipation or behavioral choices specifically in neuronal subsets preferring the rewarded stimulus. Therefore, learning engages diverse mechanisms that modify sensory and non-sensory representations in V1 to adjust its processing to task requirements and the behavioral relevance of visual stimuli. PMID:26051421

Improving Readability of an Evaluation Tool for Low-Income Clients Using Visual Information Processing Theories

ERIC Educational Resources Information Center

Townsend, Marilyn S.; Sylva, Kathryn; Martin, Anna; Metz, Diane; Wooten-Swanson, Patti

2008-01-01

Literacy is an issue for many low-income audiences. Using visual information processing theories, the goal was improving readability of a food behavior checklist and ultimately improving its ability to accurately capture existing changes in dietary behaviors. Using group interviews, low-income clients (n = 18) evaluated 4 visual styles. The text…

Training Preschool Children to Use Visual Imagining as a Problem-Solving Strategy for Complex Categorization Tasks

ERIC Educational Resources Information Center

Kisamore, April N.; Carr, James E.; LeBlanc, Linda A.

2011-01-01

It has been suggested that verbally sophisticated individuals engage in a series of precurrent behaviors (e.g., covert intraverbal behavior, grouping stimuli, visual imagining) to solve problems such as answering questions (Palmer, 1991; Skinner, 1953). We examined the effects of one problem solving strategy--visual imagining--on increasing…

Executive Function and Behavioral Problems in Students with Visual Impairments at Mainstream and Special Schools

ERIC Educational Resources Information Center

Heyl, Vera; Hintermair, Manfred

2015-01-01

Introduction: In this study, executive function of school-aged children with visual impairments (that is, those who are blind or have low vision) is examined in the context of behavioral problems and communicative competence. Methods: Teachers assessed the executive function of a sample of 226 visually impaired students from mainstream schools and…

21 CFR 886.1290 - Fixation device.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Fixation device. 886.1290 Section 886.1290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... ophthalmological examination. The patient directs his or her gaze so that the visual image of the object falls on...

Categorical Effects in Children's Colour Search: A Cross-Linguistic Comparison

ERIC Educational Resources Information Center

Daoutis, Christine A.; Franklin, Anna; Riddett, Amy; Clifford, Alexandra; Davies, Ian R. L.

2006-01-01

In adults, visual search for a colour target is facilitated if the target and distractors fall in different colour categories (e.g. Daoutis, Pilling, & Davies, in press). The present study explored category effects in children's colour search. The relationship between linguistic colour categories and perceptual categories was addressed by…

Guidelines for the retrofit installation of accessible pedestrian signals by the Virginia Department of Transportation : Phase II report.

DOT National Transportation Integrated Search

2005-01-01

In late 2000, the Northern Virginia District of the Virginia Department of Transportation (VDOT) received a request from a visually impaired citizen to install accessible pedestrian signals (APS) at an intersection in Falls Church. Since there were n...

Guidelines for the retrofit installation of accessible pedestrian signals by the Virginia Department of Transportation : Phase I report.

DOT National Transportation Integrated Search

2003-01-01

In late 2000, the Northern Virginia District of the Virginia Department of Transportation (VDOT) received a request from a visually impaired citizen to install accessible pedestrian signals (APS) at an intersection in Falls Church. Since there were n...

Selecting the best tone-pip stimulus-envelope time for estimating an objective middle-latency response threshold for low- and middle-tone sensorineural hearing losses.

PubMed

Xu, Z M; De Vel, E; Vinck, B; Van Cauwenberge, P

1995-01-01

The effects of rise-fall and plateau times for the Pa component of the middle-latency response (MLR) were investigated in normally hearing subjects, and an objective MLR threshold was measured in patients with low- and middle-tone hearing losses, using a selected stimulus-envelope time. Our results showed that the stimulus-envelope time (the rise-fall time and plateau time groups) affected the Pa component of the MLR (quality was determined by the (chi 2-test and amplitude by the F-test). The 4-2-4 tone-pips produced good Pa quality by visual inspection. However, our data revealed no statistically significant Na-Pa amplitude differences between the two subgroups studied when comparing the 2- and 4-ms rise-fall times and the 0- and 2-ms plateau times. In contrast, Na-Pa became significantly smaller from the 4-ms to the 6-ms rise-fall time and from the 2-ms to the 4-ms plateau time (paired t-test). This result allowed us to select the 2- or 4-ms rise-fall time and the 0- or 2-ms plateau time without influencing amplitude. Analysis of the stimulus spectral characteristics demonstrated that a rise-fall time of at least 2ms could prevent spectral splatter and indicated that a stimulus with a 5-ms rise-fall time had a greater frequency-specificity than a stimulus of 2-ms rise-fall time. When considering the synchronous discharge and frequency-specificity of MLR, our findings show that a rise-fall time of four periods with a plateau of two periods is an acceptable compromise for estimating the objective MLR threshold.(ABSTRACT TRUNCATED AT 250 WORDS)

Behavior Selection of Mobile Robot Based on Integration of Multimodal Information

NASA Astrophysics Data System (ADS)

Chen, Bin; Kaneko, Masahide

Recently, biologically inspired robots have been developed to acquire the capacity for directing visual attention to salient stimulus generated from the audiovisual environment. On purpose to realize this behavior, a general method is to calculate saliency maps to represent how much the external information attracts the robot's visual attention, where the audiovisual information and robot's motion status should be involved. In this paper, we represent a visual attention model where three modalities, that is, audio information, visual information and robot's motor status are considered, while the previous researches have not considered all of them. Firstly, we introduce a 2-D density map, on which the value denotes how much the robot pays attention to each spatial location. Then we model the attention density using a Bayesian network where the robot's motion statuses are involved. Secondly, the information from both of audio and visual modalities is integrated with the attention density map in integrate-fire neurons. The robot can direct its attention to the locations where the integrate-fire neurons are fired. Finally, the visual attention model is applied to make the robot select the visual information from the environment, and react to the content selected. Experimental results show that it is possible for robots to acquire the visual information related to their behaviors by using the attention model considering motion statuses. The robot can select its behaviors to adapt to the dynamic environment as well as to switch to another task according to the recognition results of visual attention.

Decoding Reveals Plasticity in V3A as a Result of Motion Perceptual Learning

PubMed Central

Shibata, Kazuhisa; Chang, Li-Hung; Kim, Dongho; Náñez, José E.; Kamitani, Yukiyasu; Watanabe, Takeo; Sasaki, Yuka

2012-01-01

Visual perceptual learning (VPL) is defined as visual performance improvement after visual experiences. VPL is often highly specific for a visual feature presented during training. Such specificity is observed in behavioral tuning function changes with the highest improvement centered on the trained feature and was originally thought to be evidence for changes in the early visual system associated with VPL. However, results of neurophysiological studies have been highly controversial concerning whether the plasticity underlying VPL occurs within the visual cortex. The controversy may be partially due to the lack of observation of neural tuning function changes in multiple visual areas in association with VPL. Here using human subjects we systematically compared behavioral tuning function changes after global motion detection training with decoded tuning function changes for 8 visual areas using pattern classification analysis on functional magnetic resonance imaging (fMRI) signals. We found that the behavioral tuning function changes were extremely highly correlated to decoded tuning function changes only in V3A, which is known to be highly responsive to global motion with human subjects. We conclude that VPL of a global motion detection task involves plasticity in a specific visual cortical area. PMID:22952849

Visual perception and interception of falling objects: a review of evidence for an internal model of gravity.

PubMed

Zago, Myrka; Lacquaniti, Francesco

2005-09-01

Prevailing views on how we time the interception of a moving object assume that the visual inputs are informationally sufficient to estimate the time-to-contact from the object's kinematics. However, there are limitations in the visual system that raise questions about the general validity of these theories. Most notably, vision is poorly sensitive to arbitrary accelerations. How then does the brain deal with the motion of objects accelerated by Earth's gravity? Here we review evidence in favor of the view that the brain makes the best estimate about target motion based on visually measured kinematics and an a priori guess about the causes of motion. According to this theory, a predictive model is used to extrapolate time-to-contact from the expected kinetics in the Earth's gravitational field.

Exercise-Based Fall Prevention in the Elderly: What About Agility?

PubMed

Donath, Lars; van Dieën, Jaap; Faude, Oliver

2016-02-01

Annually, one in three seniors aged over 65 years fall. Balance and strength training can reduce neuromuscular fall risk factors and fall rates. Besides conventional balance and strength training, explosive or high-velocity strength training, eccentric exercises, perturbation-based balance training, trunk strength, and trunk control have also been emphasized. In contrast, aerobic exercise has to date not been included in fall-prevention studies. However, well-developed endurance capacity might attenuate fatigue-induced declines in postural control in sports-related or general activities of daily living. Physical performance indices, such as balance, strength, and endurance, are generally addressed independently in exercise guidelines. This approach seems time consuming and may impede integrative training of sensorimotor, neuromuscular, and cardiocirculatory functions required to deal with balance-threatening situations in the elderly. An agility-based conceptual training framework comprising perception and decision making (e.g., visual scanning, pattern recognition, anticipation) and changes of direction (e.g., sudden starts, stops and turns; reactive control; concentric and eccentric contractions) might enable an integrative neuromuscular, cardiocirculatory, and cognitive training. The present paper aims to provide a scientific sketch of how to build such an integrated modular training approach, allowing adaptation of intensity, complexity, and cognitive challenge of the agility tasks to the participant's capacity. Subsequent research should address the (1) link between agility and fall risk factors as well as fall rates, (2) benefit-risk ratios of the proposed approach, (3) psychosocial aspects of agility training (e.g., motivation), and (4) logistical requirements (e.g., equipment needed).

Problem Behavior and Developmental Tasks in Adolescents with Visual Impairment and Sighted Peers

ERIC Educational Resources Information Center

Pfeiffer, Jens P.; Pinquart, Martin

2013-01-01

This longitudinal study analyzed associations of problem behavior with the attainment of developmental tasks in 133 adolescents with visual impairment and 449 sighted peers. Higher levels of initial problem behavior predicted less progress in the attainment of developmental tasks at the one-year follow-up only in sighted adolescents. This…

Visualization of Sedentary Behavior Using an Event-Based Approach

ERIC Educational Resources Information Center

Loudon, David; Granat, Malcolm H.

2015-01-01

Visualization is commonly used in the interpretation of physical behavior (PB) data, either in conjunction with or as precursor to formal analysis. Effective representations of the data can enable the identification of patterns of behavior, and how they relate to the temporal context in a single day, or across multiple days. An understanding of…

Evidence that primary visual cortex is required for image, orientation, and motion discrimination by rats.

PubMed

Petruno, Sarah K; Clark, Robert E; Reinagel, Pamela

2013-01-01

The pigmented Long-Evans rat has proven to be an excellent subject for studying visually guided behavior including quantitative visual psychophysics. This observation, together with its experimental accessibility and its close homology to the mouse, has made it an attractive model system in which to dissect the thalamic and cortical circuits underlying visual perception. Given that visually guided behavior in the absence of primary visual cortex has been described in the literature, however, it is an empirical question whether specific visual behaviors will depend on primary visual cortex in the rat. Here we tested the effects of cortical lesions on performance of two-alternative forced-choice visual discriminations by Long-Evans rats. We present data from one highly informative subject that learned several visual tasks and then received a bilateral lesion ablating >90% of primary visual cortex. After the lesion, this subject had a profound and persistent deficit in complex image discrimination, orientation discrimination, and full-field optic flow motion discrimination, compared with both pre-lesion performance and sham-lesion controls. Performance was intact, however, on another visual two-alternative forced-choice task that required approaching a salient visual target. A second highly informative subject learned several visual tasks prior to receiving a lesion ablating >90% of medial extrastriate cortex. This subject showed no impairment on any of the four task categories. Taken together, our data provide evidence that these image, orientation, and motion discrimination tasks require primary visual cortex in the Long-Evans rat, whereas approaching a salient visual target does not.

Spatiotemporal phenological changes in fall foliage peak coloration in deciduous forest and the responses to climatic variation

NASA Astrophysics Data System (ADS)

Xie, Y.; Wilson, A. M.

2017-12-01

Plant phenology studies typically focus on the beginning and end of the growing season in temperate forests. We know too little about fall foliage peak coloration, which is a bioindicator of plant response in autumn to environmental changes, an important visual cue in fall associated with animal activities, and a key element in fall foliage ecotourism. Spatiotemporal changes in timing of fall foliage peak coloration of temperate forests and the associated environmental controls are not well understood. In this study, we examined multiple color indices to estimate Land Surface Phenology (LSP) of fall foliage peak coloration of deciduous forest in the northeastern USA using Moderate Resolution Imaging Spectroradiometer (MODIS) daily imagery from 2000 to 2015. We used long term phenology ground observations to validate our estimated LSP, and found that Visible Atmospherically Resistant Index (VARI) and Plant Senescence Reflectance Index (PSRI) were good metrics to estimate peak and end of leaf coloration period of deciduous forest. During the past 16 years, the length of period with peak fall foliage color of deciduous forest at southern New England and northern Appalachian forests regions became longer (0.3 7.7 days), mainly driven by earlier peak coloration. Northern New England, southern Appalachian forests and Ozark and Ouachita mountains areas had shorter period (‒0.2 ‒9.2 days) mainly due to earlier end of leaf coloration. Changes in peak and end of leaf coloration not only were associated with changing temperature in spring and fall, but also to drought and heat in summer, and heavy precipitation in both summer and fall. The associations between leaf peak coloration phenology and climatic variations were not consistent among ecoregions. Our findings suggested divergent change patterns in fall foliage peak coloration phenology in deciduous forests, and improved our understanding in the environmental control on timing of fall foliage color change.

Feasibility [corrected] of regular physical exercise for patients with moderate to severe Alzheimer disease.

PubMed

Rolland, Y; Rival, L; Pillard, F; Lafont, C; Rivére, D; Albaréde, J; Vellas, B

2000-01-01

Physical activity delays loss of autonomy in the elderly. In patients with Alzheimer disease (AD), physical activity could be a useful strategy in therapeutic management by delaying loss of functional independence and the usual complications of the disease. To determine, using standardized tools, the effects on autonomy (ADL, IADL), cognitive function (MMS), nutritional status (MNA), behavioral problems (NPI) and risk of falls (Tinetti test) of a physical exercise program in patients with AD. Twenty-three subjects (13 men and 10 women, aged 71-92 years, mean 78 years) with AD (mean MMS 16, range 1-23) carried out for a mean of 7 weeks (5-12 weeks) a program of endurance exercise (walking, exercise bicycle) adapted to their individual capacities. Standardized gerontological evaluation was performed before and after the study. No significant change in autonomy (ADL, IADL) was observed. There was an improvement in the MNA (p<0.001) and the MMS (p<0.001). Risk of falls (p<0.01) and behavioral problems (p<0.05) decreased. These results were obtained without increasing family workload. We suggest that physical activity is a therapeutic option which can reduce nutritional and behavioral complications and risk of falls in subjects with AD.

Can variations in visual behavior measures be good predictors of driver sleepiness? A real driving test study.

PubMed

Wang, Yonggang; Xin, Mengyang; Bai, Han; Zhao, Yangdong

2017-02-17

The primary purpose of this study was to examine the association between variations in visual behavior measures and subjective sleepiness levels across age groups over time to determine a quantitative method of measuring drivers' sleepiness levels. A total of 128 volunteer drivers in 4 age groups were asked to finish 2-, 3-, and 4-h continuous driving tasks on expressways, during which the driver's fixation, saccade, and blink measures were recorded by an eye-tracking system and the subjective sleepiness level was measured through the Stanford Sleepiness Scale. Two-way repeated measures analysis of variance was then used to examine the change in visual behavior measures across age groups over time and compare the interactive effects of these 2 factors on the dependent visual measures. Drivers' visual behavior measures and subjective sleepiness levels vary significantly over time but not across age groups. A statistically significant interaction between age group and driving duration was found in drivers' pupil diameter, deviation of search angle, saccade amplitude, blink frequency, blink duration, and closure duration. Additionally, change in a driver's subjective sleepiness level is positively or negatively associated with variation in visual behavior measures, and such relationships can be expressed in regression models for different period of driving duration. Driving duration affects drivers' sleepiness significantly, so the amount of continuous driving time should be strictly controlled. Moreover, driving sleepiness can be quantified through the change rate of drivers' visual behavior measures to alert drivers of sleepiness risk and to encourage rest periods. These results provide insight into potential strategies for reducing and preventing traffic accidents and injuries.

Visual processing during recovery from vegetative state to consciousness: comparing behavioral indices to brain responses.

PubMed

Wijnen, V J M; Eilander, H J; de Gelder, B; van Boxtel, G J M

2014-11-01

Auditory stimulation is often used to evoke responses in unresponsive patients who have suffered severe brain injury. In order to investigate visual responses, we examined visual evoked potentials (VEPs) and behavioral responses to visual stimuli in vegetative patients during recovery to consciousness. Behavioral responses to visual stimuli (visual localization, comprehension of written commands, and object manipulation) and flash VEPs were repeatedly examined in eleven vegetative patients every two weeks for an average period of 2.6months, and patients' VEPs were compared to a healthy control group. Long-term outcome of the patients was assessed 2-3years later. Visual response scores increased during recovery to consciousness for all scales: visual localization, comprehension of written commands, and object manipulation. VEP amplitudes were smaller, and latencies were longer in the patient group relative to the controls. VEPs characteristics at first measurement were related to long-term outcome up to three years after injury. Our findings show the improvement of visual responding with recovery from the vegetative state to consciousness. Elementary visual processing is present, yet according to VEP responses, poorer in vegetative and minimally conscious state than in healthy controls, and remains poorer when patients recovered to consciousness. However, initial VEPs are related to long-term outcome. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Completing College: A National View of Student Completion Rates--Fall 2011 Cohort. (Signature Report No. 14)

ERIC Educational Resources Information Center

Shapiro, Doug; Dundar, Afet; Huie, Faye; Wakhungu, Phoebe Khasiala; Yuan, Xin; Nathan, Angel; Bhimdiwala, Ayesha

2017-01-01

This Signature Report examines the rate of completion of postsecondary certificates and degrees by first-time-in-college degree-seeking students who initially enrolled in two- and four-year colleges and universities (public, private nonprofit, or private for-profit) nationwide in fall 2011. It tracks their enrollment behaviors and outcomes for six…

Tandem Stance Avoidance Using Adaptive and Asymmetric Admittance Control for Fall Prevention.

PubMed

Nakagawa, Shotaro; Hasegawa, Yasuhisa; Fukuda, Toshio; Kondo, Izumi; Tanimoto, Masanori; Di, Pei; Huang, Jian; Huang, Qiang

2016-05-01

Fall prevention is one of the most important functions of walking assistance devices for user's safety. It is preferable that these devices prevent the user from being in the state where the risk of falling is high rather than helping them recovering from falling motion. During turning, when the user is in the tandem stance, a state where both legs form a line along walking direction, a support base that is surrounded by two legs becomes small, and a stability margin becomes small. This paper therefore aims to prevent the tandem stance by using nonwearable robot "intelligent cane" for the elderly or physically challenged person. Generally, the behavior of the lower limb follows the upper body turning. This paper therefore introduces a cane robot control method which constrains the behavior of user's upper body. By adjusting an admittance parameter of the robot according to the positions of a support leg, the robot resists to turn while a support leg is on the same side of the turning direction. A swing leg on the turning direction side therefore freely moves to the turning direction, while a swing leg on the opposite direction side of turning hardly move to the turning direction.

Gravity Modeling for Variable Fidelity Environments

NASA Technical Reports Server (NTRS)

Madden, Michael M.

2006-01-01

Aerospace simulations can model worlds, such as the Earth, with differing levels of fidelity. The simulation may represent the world as a plane, a sphere, an ellipsoid, or a high-order closed surface. The world may or may not rotate. The user may select lower fidelity models based on computational limits, a need for simplified analysis, or comparison to other data. However, the user will also wish to retain a close semblance of behavior to the real world. The effects of gravity on objects are an important component of modeling real-world behavior. Engineers generally equate the term gravity with the observed free-fall acceleration. However, free-fall acceleration is not equal to all observers. To observers on the sur-face of a rotating world, free-fall acceleration is the sum of gravitational attraction and the centrifugal acceleration due to the world's rotation. On the other hand, free-fall acceleration equals gravitational attraction to an observer in inertial space. Surface-observed simulations (e.g. aircraft), which use non-rotating world models, may choose to model observed free fall acceleration as the gravity term; such a model actually combines gravitational at-traction with centrifugal acceleration due to the Earth s rotation. However, this modeling choice invites confusion as one evolves the simulation to higher fidelity world models or adds inertial observers. Care must be taken to model gravity in concert with the world model to avoid denigrating the fidelity of modeling observed free fall. The paper will go into greater depth on gravity modeling and the physical disparities and synergies that arise when coupling specific gravity models with world models.

Visual Working Memory Enhances the Neural Response to Matching Visual Input.

PubMed

Gayet, Surya; Guggenmos, Matthias; Christophel, Thomas B; Haynes, John-Dylan; Paffen, Chris L E; Van der Stigchel, Stefan; Sterzer, Philipp

2017-07-12

Visual working memory (VWM) is used to maintain visual information available for subsequent goal-directed behavior. The content of VWM has been shown to affect the behavioral response to concurrent visual input, suggesting that visual representations originating from VWM and from sensory input draw upon a shared neural substrate (i.e., a sensory recruitment stance on VWM storage). Here, we hypothesized that visual information maintained in VWM would enhance the neural response to concurrent visual input that matches the content of VWM. To test this hypothesis, we measured fMRI BOLD responses to task-irrelevant stimuli acquired from 15 human participants (three males) performing a concurrent delayed match-to-sample task. In this task, observers were sequentially presented with two shape stimuli and a retro-cue indicating which of the two shapes should be memorized for subsequent recognition. During the retention interval, a task-irrelevant shape (the probe) was briefly presented in the peripheral visual field, which could either match or mismatch the shape category of the memorized stimulus. We show that this probe stimulus elicited a stronger BOLD response, and allowed for increased shape-classification performance, when it matched rather than mismatched the concurrently memorized content, despite identical visual stimulation. Our results demonstrate that VWM enhances the neural response to concurrent visual input in a content-specific way. This finding is consistent with the view that neural populations involved in sensory processing are recruited for VWM storage, and it provides a common explanation for a plethora of behavioral studies in which VWM-matching visual input elicits a stronger behavioral and perceptual response. SIGNIFICANCE STATEMENT Humans heavily rely on visual information to interact with their environment and frequently must memorize such information for later use. Visual working memory allows for maintaining such visual information in the mind's eye after termination of its retinal input. It is hypothesized that information maintained in visual working memory relies on the same neural populations that process visual input. Accordingly, the content of visual working memory is known to affect our conscious perception of concurrent visual input. Here, we demonstrate for the first time that visual input elicits an enhanced neural response when it matches the content of visual working memory, both in terms of signal strength and information content. Copyright © 2017 the authors 0270-6474/17/376638-10$15.00/0.

Rockfall hazard and risk assessment in the Yosemite Valley, California, USA

USGS Publications Warehouse

Guzzetti, F.; Reichenbach, P.; Wieczorek, G.F.

2003-01-01

Rock slides and rock falls are the most frequent types of slope movements in Yosemite National Park, California. In historical time (1857-2002) 392 rock falls and rock slides have been documented in the valley, and some of them have been mapped in detail. We present the results of an attempt to assess rock fall hazards in the Yosemite Valley. Spatial and temporal aspects of rock falls hazard are considered. A detailed inventory of slope movements covering the 145-year period from 1857 to 2002 is used to determine the frequency-volume statistics of rock falls and to estimate the annual frequency of rock falls, providing the temporal component of rock fall hazard. The extent of the areas potentially subject to rock fall hazards in the Yosemite Valley were obtained using STONE, a physically-based rock fall simulation computer program. The software computes 3-dimensional rock fall trajectories starting from a digital elevation model (DEM), the location of rock fall release points, and maps of the dynamic rolling friction coefficient and of the coefficients of normal and tangential energy restitution. For each DEM cell the software calculates the number of rock falls passing through the cell, the maximum rock fall velocity and the maximum flying height. For the Yosemite Valley, a DEM with a ground resolution of 10 ?? 10 m was prepared using topographic contour lines from the U.S. Geological Survey 1:24 000-scale maps. Rock fall release points were identified as DEM cells having a slope steeper than 60??, an assumption based on the location of historical rock falls. Maps of the normal and tangential energy restitution coefficients and of the rolling friction coefficient were produced from a surficial geologic map. The availability of historical rock falls mapped in detail allowed us to check the computer program performance and to calibrate the model parameters. Visual and statistical comparison of the model results with the mapped rock falls confirmed the accuracy of the model. The model results are compared with a previous map of rockfall talus and with a geomorphic assessment of rock fall hazard based on potential energy referred to as a shadow angle approach, recently completed for the Yosemite Valley. The model results are then used to identify the roads and trails more subject to rock fall hazard. Of the 166.5 km of roads and trails in the Yosemite Valley 31.2% were found to be potentially subject to rock fall hazard, of which 14% are subject to very high hazard. ?? European Geosciences Union 2003.

Parallel neural pathways in higher visual centers of the Drosophila brain that mediate wavelength-specific behavior

PubMed Central

Otsuna, Hideo; Shinomiya, Kazunori; Ito, Kei

2014-01-01

Compared with connections between the retinae and primary visual centers, relatively less is known in both mammals and insects about the functional segregation of neural pathways connecting primary and higher centers of the visual processing cascade. Here, using the Drosophila visual system as a model, we demonstrate two levels of parallel computation in the pathways that connect primary visual centers of the optic lobe to computational circuits embedded within deeper centers in the central brain. We show that a seemingly simple achromatic behavior, namely phototaxis, is under the control of several independent pathways, each of which is responsible for navigation towards unique wavelengths. Silencing just one pathway is enough to disturb phototaxis towards one characteristic monochromatic source, whereas phototactic behavior towards white light is not affected. The response spectrum of each demonstrable pathway is different from that of individual photoreceptors, suggesting subtractive computations. A choice assay between two colors showed that these pathways are responsible for navigation towards, but not for the detection itself of, the monochromatic light. The present study provides novel insights about how visual information is separated and processed in parallel to achieve robust control of an innate behavior. PMID:24574974

Promising Behavior Change Techniques in a Multicomponent Intervention to Reduce Concerns about Falls in Old Age: A Delphi Study

ERIC Educational Resources Information Center

Vestjens, Lotte; Kempen, Gertrudis I. J. M.; Crutzen, Rik; Kok, Gerjo; Zijlstra, G. A. Rixt

2015-01-01

Complex behavior change interventions need evidence regarding the effectiveness of individual components to understand how these interventions work. The objective of this study was to identify the least and most promising behavior change techniques (BCTs) within the Dutch intervention "A Matter of Balance" (AMB-NL) aimed at concerns…

Multiple Sensory-Motor Pathways Lead to Coordinated Visual Attention

PubMed Central

Yu, Chen; Smith, Linda B.

2016-01-01

Joint attention has been extensively studied in the developmental literature because of overwhelming evidence that the ability to socially coordinate visual attention to an object is essential to healthy developmental outcomes, including language learning. The goal of the present study is to understand the complex system of sensory-motor behaviors that may underlie the establishment of joint attention between parents and toddlers. In an experimental task, parents and toddlers played together with multiple toys. We objectively measured joint attention – and the sensory-motor behaviors that underlie it – using a dual head-mounted eye-tracking system and frame-by-frame coding of manual actions. By tracking the momentary visual fixations and hand actions of each participant, we precisely determined just how often they fixated on the same object at the same time, the visual behaviors that preceded joint attention, and manual behaviors that preceded and co-occurred with joint attention. We found that multiple sequential sensory-motor patterns lead to joint attention. In addition, there are developmental changes in this multi-pathway system evidenced as variations in strength among multiple routes. We propose that coordinated visual attention between parents and toddlers is primarily a sensory-motor behavior. Skill in achieving coordinated visual attention in social settings – like skills in other sensory-motor domains – emerges from multiple pathways to the same functional end. PMID:27016038

Multiple Sensory-Motor Pathways Lead to Coordinated Visual Attention.

PubMed

Yu, Chen; Smith, Linda B

2017-02-01

Joint attention has been extensively studied in the developmental literature because of overwhelming evidence that the ability to socially coordinate visual attention to an object is essential to healthy developmental outcomes, including language learning. The goal of this study was to understand the complex system of sensory-motor behaviors that may underlie the establishment of joint attention between parents and toddlers. In an experimental task, parents and toddlers played together with multiple toys. We objectively measured joint attention-and the sensory-motor behaviors that underlie it-using a dual head-mounted eye-tracking system and frame-by-frame coding of manual actions. By tracking the momentary visual fixations and hand actions of each participant, we precisely determined just how often they fixated on the same object at the same time, the visual behaviors that preceded joint attention and manual behaviors that preceded and co-occurred with joint attention. We found that multiple sequential sensory-motor patterns lead to joint attention. In addition, there are developmental changes in this multi-pathway system evidenced as variations in strength among multiple routes. We propose that coordinated visual attention between parents and toddlers is primarily a sensory-motor behavior. Skill in achieving coordinated visual attention in social settings-like skills in other sensory-motor domains-emerges from multiple pathways to the same functional end. Copyright © 2016 Cognitive Science Society, Inc.

Depression and Outcome of Fear of Falling in a Falls Prevention Program.

PubMed

Iaboni, Andrea; Banez, Carol; Lam, Robert; Jones, Simon A; Maki, Brian E; Liu, Barbara A; Flint, Alastair J

2015-10-01

To examine whether depression predicts less improvement in fear of falling and falls efficacy in older adults attending a falls prevention program (FPP). Using a prospective observational design in an academic medical center, the authors studied 69 nondemented adults aged 55 years or older (mean age: 77.8±8.9 years) who had experienced at least one fall in the previous year and who attended the FPP. The primary outcome variable was change in severity of fear of falling during the FPP. Secondary outcome variables were change in falls efficacy and fear-related restriction of activities during the FPP. Independent variables were baseline depressive disorders and depressive symptom severity. Twenty-one of 69 study participants (30.4%) had a depressive disorder at baseline. Depressive disorder and depressive symptoms were not associated with change in severity of fear of falling or restriction of activity. On the other hand, depressive disorder was associated with improvement in falls efficacy, although this finding was not significant in multivariate analysis. Among participants with a depressive disorder, improvement in falls efficacy was significantly correlated with improvement in depressive symptoms. There was no association between baseline depression and change in fear of falling in this FPP. The correlation between improvement in depressive symptoms and improvement in falls efficacy raises the question as to whether a cognitive-behavioral intervention that simultaneously targets both depression and falls efficacy would be a useful component of a FPP. Copyright © 2015 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Mathematical modeling of the burden distribution in the blast furnace shaft

NASA Astrophysics Data System (ADS)

Park, Jong-In; Jung, Hun-Je; Jo, Min-Kyu; Oh, Han-Sang; Han, Jeong-Whan

2011-06-01

Process efficiency in the blast furnace is influenced by the gas flow pattern, which is dictated by the burden profile. Therefore, it is important to control the burden distribution so as to achieve reasonable gas flow in the blast furnace operation. Additionally, the charging pattern selection is important as it affects the burden trajectory and stock profile. For analysis of the burden distribution, a new analysis model was developed by use of the spreadsheet program, Microsoft® Office Excel, based on visual basic. This model is composed of the falling burden trajectory and a stock model. The burden trajectory is determined by the burden type, batch weight, rotating velocity of the chute, tilting angle, and friction coefficient. After falling, stock lines are formed by the angle of repose, which is affected by the burden trajectory and the falling velocity. The mathematical formulas for developing this model were modified by a scaled model experiment and DEM simulation.

Behavioral thermoregulation by juvenile spring and fall chinook salmon, Oncorhynchus tshawytscha, during smoltification

USGS Publications Warehouse

Sauter, S.T.; Crawshaw, L.I.; Maule, A.G.

2001-01-01

Fall chinook salmon evolved to emigrate during the summer months. The shift in the temperature preference we observed in smolting fall chinook but not spring chinook salmon may reflect a phylogenetic adaptation to summer emigration by (1) providing directional orientation as fall chinook salmon move into the marine environment, (2) maintaining optimal gill function during emigration and seawater entry, and/or (3) resetting thermoregulatory set-points to support physiological homeostasis once smolted fish enter the marine environment. Phylogenetically determined temperature adaptations and responses to thermal stress may not protect fall chinook salmon from the recent higher summer water temperatures, altered annual thermal regimes, and degraded cold water refugia that result from hydropower regulation of the Columbia and Snake rivers. The long-term survival of fall chinook salmon will likely require restoration of normal annual thermographs and rigorous changes in land use practices to protect critical thermal refugia and control maximum summer water temperatures in reservoirs.

2011 IEEE Visualization Contest winner: Visualizing unsteady vortical behavior of a centrifugal pump.

PubMed

Otto, Mathias; Kuhn, Alexander; Engelke, Wito; Theisel, Holger

2012-01-01

In the 2011 IEEE Visualization Contest, the dataset represented a high-resolution simulation of a centrifugal pump operating below optimal speed. The goal was to find suitable visualization techniques to identify regions of rotating stall that impede the pump's effectiveness. The winning entry split analysis of the pump into three parts based on the pump's functional behavior. It then applied local and integration-based methods to communicate the unsteady flow behavior in different regions of the dataset. This research formed the basis for a comparison of common vortex extractors and more recent methods. In particular, integration-based methods (separation measures, accumulated scalar fields, particle path lines, and advection textures) are well suited to capture the complex time-dependent flow behavior. This video (http://youtu.be/oD7QuabY0oU) shows simulations of unsteady flow in a centrifugal pump.

Toward the Development of a Self-Management Intervention to Promote Pro-Social Behaviors for Students with Visual Impairment

ERIC Educational Resources Information Center

Ivy, Sarah E.; Lather, Amanda B.; Hatton, Deborah D.; Wehby, Joseph H.

2016-01-01

Students with visual impairment (VI) lack access to the same models and reinforcers as students with sight. Consequentially, behaviors that children with sight acquire through observation must be explicitly taught to children with VI. In addition, children with VI have difficulty maintaining such behaviors. Therefore, interventions that promote…

Infant visual attention and object recognition.

PubMed

Reynolds, Greg D

2015-05-15

This paper explores the role visual attention plays in the recognition of objects in infancy. Research and theory on the development of infant attention and recognition memory are reviewed in three major sections. The first section reviews some of the major findings and theory emerging from a rich tradition of behavioral research utilizing preferential looking tasks to examine visual attention and recognition memory in infancy. The second section examines research utilizing neural measures of attention and object recognition in infancy as well as research on brain-behavior relations in the early development of attention and recognition memory. The third section addresses potential areas of the brain involved in infant object recognition and visual attention. An integrated synthesis of some of the existing models of the development of visual attention is presented which may account for the observed changes in behavioral and neural measures of visual attention and object recognition that occur across infancy. Copyright © 2015 Elsevier B.V. All rights reserved.

TargetVue: Visual Analysis of Anomalous User Behaviors in Online Communication Systems.

PubMed

Cao, Nan; Shi, Conglei; Lin, Sabrina; Lu, Jie; Lin, Yu-Ru; Lin, Ching-Yung

2016-01-01

Users with anomalous behaviors in online communication systems (e.g. email and social medial platforms) are potential threats to society. Automated anomaly detection based on advanced machine learning techniques has been developed to combat this issue; challenges remain, though, due to the difficulty of obtaining proper ground truth for model training and evaluation. Therefore, substantial human judgment on the automated analysis results is often required to better adjust the performance of anomaly detection. Unfortunately, techniques that allow users to understand the analysis results more efficiently, to make a confident judgment about anomalies, and to explore data in their context, are still lacking. In this paper, we propose a novel visual analysis system, TargetVue, which detects anomalous users via an unsupervised learning model and visualizes the behaviors of suspicious users in behavior-rich context through novel visualization designs and multiple coordinated contextual views. Particularly, TargetVue incorporates three new ego-centric glyphs to visually summarize a user's behaviors which effectively present the user's communication activities, features, and social interactions. An efficient layout method is proposed to place these glyphs on a triangle grid, which captures similarities among users and facilitates comparisons of behaviors of different users. We demonstrate the power of TargetVue through its application in a social bot detection challenge using Twitter data, a case study based on email records, and an interview with expert users. Our evaluation shows that TargetVue is beneficial to the detection of users with anomalous communication behaviors.

Role of sensory cues on food searching behavior of a captive Manta birostris (Chondrichtyes, Mobulidae).

PubMed

Ari, Csilla; Correia, João P

2008-07-01

This study reports on the first experimental research designed specifically for Manta birostris behavior. The authors attempted to learn about the feeding behavior and environmental cues influencing this behavior, as well as general cognitive ability. The preconditioned Manta's ability to identify food, on the basis of a fraction of the ordinary food signal complex, was tested. The opening of cephalic fins was considered a good indicator of feeding motivation level. The study subject animal used its biological clock to predict time and also associated a specific location with food, suggesting an ability to build up a cognitive map of its environment. Both underwater visual stimuli and olfactory stimuli had a very intense effect on food searching behavior over a 30 m distance, in contrast to visual signs from above the water surface. In addition, although an underwater visual signal resulted in a more intense response than from an olfactory signal, the specimen did not discriminate between different objects tested on the basis of visual sensation. It could therefore be suggested that food searching behavior of Mantas are governed by triggering stimuli, including smell or visual recognition, and modulated by the cognitive spatial map stored in their long-term memory. These findings will hopefully prove useful while devising protecting policies in the natural environment and/or while keeping these animals in captivity. Zoo Biol 27:294-304, 2008. (c) 2008 Wiley-Liss, Inc.

Virtual reality applications in assessing the effect of anxiety on sensorimotor integration in human postural control.

PubMed

Widdowson, Christopher; Ganhotra, Jatin; Faizal, Mohammed; Wilko, Marissa; Parikh, Saurin; Adhami, Zainulabidin; Hernandez, Manuel E

2016-08-01

Falls are a leading cause of injury and mortality among adults over the age of 65 years. Given the strong relation between fear of falling and fall risk, identification of the mechanisms that underlie anxiety-related changes in postural control may pave the way to the development of novel therapeutic strategies aimed at reducing fall risk in older adults. First, we review potential mechanisms underlying anxiety-mediated changes in postural control in older adults with and without neurological conditions. We then present a system that allows for the simultaneous recording of neural, physiological, and behavioral data in an immersive virtual reality (VR) environment while implementing sensory and mechanical perturbations to evaluate alterations in sensorimotor integration under conditions with high postural threat. We also discuss applications of VR in minimizing falls in older adults and potential future studies.

Survival of falling robots

NASA Astrophysics Data System (ADS)

Cameron, Jonathan M.; Arkin, Ronald C.

1992-02-01

As mobile robots are used in more uncertain and dangerous environments, it will become important to design them so that they can survive falls. In this paper, we examine a number of mechanisms and strategies that animals use to withstand these potentially catastrophic events and extend them to the design of robots. A brief survey of several aspects of how common cats survive falls provides an understanding of the issues involved in preventing traumatic injury during a falling event. After outlining situations in which robots might fall, a number of factors affecting their survival are described. From this background, several robot design guidelines are derived. These include recommendations for the physical structure of the robot as well as requirements for the robot control architecture. A control architecture is proposed based on reactive control techniques and action-oriented perception that is geared to support this form of survival behavior.

Survival of falling robots

NASA Technical Reports Server (NTRS)

Cameron, Jonathan M.; Arkin, Ronald C.

1992-01-01

As mobile robots are used in more uncertain and dangerous environments, it will become important to design them so that they can survive falls. In this paper, we examine a number of mechanisms and strategies that animals use to withstand these potentially catastrophic events and extend them to the design of robots. A brief survey of several aspects of how common cats survive falls provides an understanding of the issues involved in preventing traumatic injury during a falling event. After outlining situations in which robots might fall, a number of factors affecting their survival are described. From this background, several robot design guidelines are derived. These include recommendations for the physical structure of the robot as well as requirements for the robot control architecture. A control architecture is proposed based on reactive control techniques and action-oriented perception that is geared to support this form of survival behavior.

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

PubMed

Ossmy, Ori; Mukamel, Roy

2018-05-15

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

Physical and Visual Accessibilities in Intensive Care Units: A Comparative Study of Open-Plan and Racetrack Units.

PubMed

Rashid, Mahbub; Khan, Nayma; Jones, Belinda

2016-01-01

This study compared physical and visual accessibilities and their associations with staff perception and interaction behaviors in 2 intensive care units (ICUs) with open-plan and racetrack layouts. For the study, physical and visual accessibilities were measured using the spatial analysis techniques of Space Syntax. Data on staff perception were collected from 81 clinicians using a questionnaire survey. The locations of 2233 interactions, and the location and length of another 339 interactions in these units were collected using systematic field observation techniques. According to the study, physical and visual accessibilities were different in the 2 ICUs, and clinicians' primary workspaces were physically and visually more accessible in the open-plan ICU. Physical and visual accessibilities affected how well clinicians' knew their peers and where their peers were located in these units. Physical and visual accessibilities also affected clinicians' perception of interaction and communication and of teamwork and collaboration in these units. Additionally, physical and visual accessibilities showed significant positive associations with interaction behaviors in these units, with the open-plan ICU showing stronger associations. However, physical accessibilities were less important than visual accessibilities in relation to interaction behaviors in these ICUs. The implications of these findings for ICU design are discussed.

Eyes Matched to the Prize: The State of Matched Filters in Insect Visual Circuits.

PubMed

Kohn, Jessica R; Heath, Sarah L; Behnia, Rudy

2018-01-01

Confronted with an ever-changing visual landscape, animals must be able to detect relevant stimuli and translate this information into behavioral output. A visual scene contains an abundance of information: to interpret the entirety of it would be uneconomical. To optimally perform this task, neural mechanisms exist to enhance the detection of important features of the sensory environment while simultaneously filtering out irrelevant information. This can be accomplished by using a circuit design that implements specific "matched filters" that are tuned to relevant stimuli. Following this rule, the well-characterized visual systems of insects have evolved to streamline feature extraction on both a structural and functional level. Here, we review examples of specialized visual microcircuits for vital behaviors across insect species, including feature detection, escape, and estimation of self-motion. Additionally, we discuss how these microcircuits are modulated to weigh relevant input with respect to different internal and behavioral states.

Neural circuits underlying visually evoked escapes in larval zebrafish

PubMed Central

Dunn, Timothy W.; Gebhardt, Christoph; Naumann, Eva A.; Riegler, Clemens; Ahrens, Misha B.; Engert, Florian; Del Bene, Filippo

2015-01-01

SUMMARY Escape behaviors deliver organisms away from imminent catastrophe. Here, we characterize behavioral responses of freely swimming larval zebrafish to looming visual stimuli simulating predators. We report that the visual system alone can recruit lateralized, rapid escape motor programs, similar to those elicited by mechanosensory modalities. Two-photon calcium imaging of retino-recipient midbrain regions isolated the optic tectum as an important center processing looming stimuli, with ensemble activity encoding the critical image size determining escape latency. Furthermore, we describe activity in retinal ganglion cell terminals and superficial inhibitory interneurons in the tectum during looming and propose a model for how temporal dynamics in tectal periventricular neurons might arise from computations between these two fundamental constituents. Finally, laser ablations of hindbrain circuitry confirmed that visual and mechanosensory modalities share the same premotor output network. Together, we establish a circuit for the processing of aversive stimuli in the context of an innate visual behavior. PMID:26804997

Elementary Visual Hallucinations and Their Relationships to Neural Pattern-Forming Mechanisms

ERIC Educational Resources Information Center

Billock, Vincent A.; Tsou, Brian H.

2012-01-01

An extraordinary variety of experimental (e.g., flicker, magnetic fields) and clinical (epilepsy, migraine) conditions give rise to a surprisingly common set of elementary hallucinations, including spots, geometric patterns, and jagged lines, some of which also have color, depth, motion, and texture. Many of these simple hallucinations fall into a…

Project ME: A Report on the Learning Wall System.

ERIC Educational Resources Information Center

Heilig, Morton L.

The learning wall system, which consists primarily of a special wall used instead of a screen for a variety of projection purposes, is described, shown diagrammatically, and pictured. Designed to provide visual perceptual motor training on a level that would fall between gross and fine motor performance for perceptually handicapped children, the…

Faster than "g", Revisited with High-Speed Imaging

ERIC Educational Resources Information Center

Vollmer, Michael; Mollmann, Klaus-Peter

2012-01-01

The introduction of modern high-speed cameras in physics teaching provides a tool not only for easy visualization, but also for quantitative analysis of many simple though fast occurring phenomena. As an example, we present a very well-known demonstration experiment--sometimes also discussed in the context of falling chimneys--which is commonly…

Reading Pictures: An Interview with David Wiesner

ERIC Educational Resources Information Center

Varga-Dobai, Kinga

2008-01-01

Two-time Caldecott Honor winner (Free Fall, Sector 7) and three-time Caldecott Medal winner (Tuesday, The Three Pigs, Flotsam), David Wiesner is regarded as one of the most remarkable creators of visual storytelling living today. Wiesner is well known for his innovative and unique subject matter and his sophisticated painting-like illustrations…

Design of control-group conditions in clinical trials of behavioral interventions.

PubMed

Lindquist, Ruth; Wyman, Jean F; Talley, Kristine M C; Findorff, Mary J; Gross, Cynthia R

2007-01-01

To review considerations in the design of placebo (attention) control conditions for community-based clinical trials of health behavior change interventions and to provide practical strategies for the design of control conditions. A well-designed control condition is an essential component of a clinical trial to foster the unambiguous interpretation of study findings. Pitfalls in the design of control conditions in clinical trials of behavioral interventions are identified and strategies to address them are offered. Types of control conditions that have been used in fall prevention trials are described, along with their strengths and weaknesses. The control condition used in the recent fall evaluation and prevention program (FEPP) was designed to overcome limitations of previous trial designs; it is provided to illustrate how to apply specific design principles. Pitfalls in the design of behavioral intervention studies may be avoided with the application of sound design principles. The FEPP active control condition can be used as a model in the design of future studies.

Identifying nursing home residents at risk for falling.

PubMed

Kiely, D K; Kiel, D P; Burrows, A B; Lipsitz, L A

1998-05-01

To develop a fall risk model that can be used to identify prospectively nursing home residents at risk for falling. The secondary objective was to determine whether the nursing home environment independently influenced the development of falls. A prospective study involving 1 year of follow-up. Two hundred seventy-two nursing homes in the state of Washington. A total of 18,855 residents who had a baseline assessment in 1991 and a follow-up assessment within the subsequent year. Baseline Minimum Data Set items that could be potential risk factors for falling were considered as independent variables. The dependent variable was whether the resident fell as reported at the follow-up assessment. We estimated the extrinsic risk attributable to particular nursing home environments by calculating the annual fall rate in each nursing home and grouping them into tertiles of fall risk according to these rates. Factors associated independently with falling were fall history, wandering behavior, use of a cane or walker, deterioration of activities of daily living performance, age greater than 87 years, unsteady gait, transfer independence, wheelchair independence, and male gender. Nursing home residents with a fall history were more than three times as likely to fall during the follow-up period than residents without a fall history. Residents in homes with the highest tertile of fall rates were more than twice as likely to fall compared with residents of homes in the lowest tertile, independent of resident-specific risk factors. Fall history was identified as the strongest risk factor associated with subsequent falls and accounted for the vast majority of the predictive strength of the model. We recommend that fall history be used as an initial screener for determining eligibility for fall intervention efforts. Studies are needed to determine the facility characteristics that contribute to fall risk, independent of resident-specific risk factors.

Visual analytics of large multidimensional data using variable binned scatter plots

NASA Astrophysics Data System (ADS)

Hao, Ming C.; Dayal, Umeshwar; Sharma, Ratnesh K.; Keim, Daniel A.; Janetzko, Halldór

2010-01-01

The scatter plot is a well-known method of visualizing pairs of two-dimensional continuous variables. Multidimensional data can be depicted in a scatter plot matrix. They are intuitive and easy-to-use, but often have a high degree of overlap which may occlude a significant portion of data. In this paper, we propose variable binned scatter plots to allow the visualization of large amounts of data without overlapping. The basic idea is to use a non-uniform (variable) binning of the x and y dimensions and plots all the data points that fall within each bin into corresponding squares. Further, we map a third attribute to color for visualizing clusters. Analysts are able to interact with individual data points for record level information. We have applied these techniques to solve real-world problems on credit card fraud and data center energy consumption to visualize their data distribution and cause-effect among multiple attributes. A comparison of our methods with two recent well-known variants of scatter plots is included.

How Fast Do Objects Fall in Visual Memory? Uncovering the Temporal and Spatial Features of Representational Gravity

PubMed Central

De Sá Teixeira, Nuno

2016-01-01

Visual memory for the spatial location where a moving target vanishes has been found to be systematically displaced downward in the direction of gravity. Moreover, it was recently reported that the magnitude of the downward error increases steadily with increasing retention intervals imposed after object’s offset and before observers are allowed to perform the spatial localization task, in a pattern where the remembered vanishing location drifts downward as if following a falling trajectory. This outcome was taken to reflect the dynamics of a representational model of earth’s gravity. The present study aims to establish the spatial and temporal features of this downward drift by taking into account the dynamics of the motor response. The obtained results show that the memory for the last location of the target drifts downward with time, thus replicating previous results. Moreover, the time taken for completion of the behavioural localization movements seems to add to the imposed retention intervals in determining the temporal frame during which the visual memory is updated. Overall, it is reported that the representation of spatial location drifts downward by about 3 pixels for each two-fold increase of time until response. The outcomes are discussed in relation to a predictive internal model of gravity which outputs an on-line spatial update of remembered objects’ location. PMID:26910260

Lower pitch is larger, yet falling pitches shrink.

PubMed

Eitan, Zohar; Schupak, Asi; Gotler, Alex; Marks, Lawrence E

2014-01-01

Experiments using diverse paradigms, including speeded discrimination, indicate that pitch and visually-perceived size interact perceptually, and that higher pitch is congruent with smaller size. While nearly all of these studies used static stimuli, here we examine the interaction of dynamic pitch and dynamic size, using Garner's speeded discrimination paradigm. Experiment 1 examined the interaction of continuous rise/fall in pitch and increase/decrease in object size. Experiment 2 examined the interaction of static pitch and size (steady high/low pitches and large/small visual objects), using an identical procedure. Results indicate that static and dynamic auditory and visual stimuli interact in opposite ways. While for static stimuli (Experiment 2), higher pitch is congruent with smaller size (as suggested by earlier work), for dynamic stimuli (Experiment 1), ascending pitch is congruent with growing size, and descending pitch with shrinking size. In addition, while static stimuli (Experiment 2) exhibit both congruence and Garner effects, dynamic stimuli (Experiment 1) present congruence effects without Garner interference, a pattern that is not consistent with prevalent interpretations of Garner's paradigm. Our interpretation of these results focuses on effects of within-trial changes on processing in dynamic tasks and on the association of changes in apparent size with implied changes in distance. Results suggest that static and dynamic stimuli can differ substantially in their cross-modal mappings, and may rely on different processing mechanisms.

How Fast Do Objects Fall in Visual Memory? Uncovering the Temporal and Spatial Features of Representational Gravity.

PubMed

De Sá Teixeira, Nuno

2016-01-01

Visual memory for the spatial location where a moving target vanishes has been found to be systematically displaced downward in the direction of gravity. Moreover, it was recently reported that the magnitude of the downward error increases steadily with increasing retention intervals imposed after object's offset and before observers are allowed to perform the spatial localization task, in a pattern where the remembered vanishing location drifts downward as if following a falling trajectory. This outcome was taken to reflect the dynamics of a representational model of earth's gravity. The present study aims to establish the spatial and temporal features of this downward drift by taking into account the dynamics of the motor response. The obtained results show that the memory for the last location of the target drifts downward with time, thus replicating previous results. Moreover, the time taken for completion of the behavioural localization movements seems to add to the imposed retention intervals in determining the temporal frame during which the visual memory is updated. Overall, it is reported that the representation of spatial location drifts downward by about 3 pixels for each two-fold increase of time until response. The outcomes are discussed in relation to a predictive internal model of gravity which outputs an on-line spatial update of remembered objects' location.

Effectiveness of individualized fall prevention program in geriatric rehabilitation hospital setting: a cluster randomized trial.

PubMed

Aizen, Efraim; Lutsyk, Galina; Wainer, Lea; Carmeli, Sarit

2015-10-01

There is no conclusive evidence that hospital fall prevention programs can reduce the number of falls. We aimed to investigate the effect of a targeted individualized falls prevention program in a geriatric rehabilitation hospital. This was a two-stage cluster-controlled trial carried out in five geriatric rehabilitation wards. Participants were 752 patients with mean age 83.2 years. The intervention was a two-phase targeted intervention falls prevention program. The intervention included an assessment of patient's risk by a risk assessment tool and an individual management that includes medical, behavioral, cognitive and environmental modifications. Patients with moderate risk received additionally orientation guidance, and mobility restriction. Patients determined as high risk were additionally placed under permanent personal supervision. Outcome measures were falls during hospital stay. In both stages of the trial, intervention and control wards were almost similar at baseline for individual patient characteristics. Overall, 37 falls occurred during the study. No significant difference was found in fall rates during follow-up between intervention and control wards: 1.306 falls per 1000 bed days in the intervention groups and 1.763-1.826 falls per 1000 bed days in the control groups. The adjusted hazard ratio for falls in the intervention groups was 1.36 (95 % confidence interval 0.89-1.77) (P = 0.08) in the first stage and 1.27 (95 % confidence interval 0.92-1.67) (P = 0.12) in the second stage. These results suggest that in a geriatric rehabilitation hospital a targeted individualized intervention falls prevention program is not effective in reducing falls.

Neural practice effect during cross-modal selective attention: Supra-modal and modality-specific effects.

PubMed

Xia, Jing; Zhang, Wei; Jiang, Yizhou; Li, You; Chen, Qi

2018-05-16

Practice and experiences gradually shape the central nervous system, from the synaptic level to large-scale neural networks. In natural multisensory environment, even when inundated by streams of information from multiple sensory modalities, our brain does not give equal weight to different modalities. Rather, visual information more frequently receives preferential processing and eventually dominates consciousness and behavior, i.e., visual dominance. It remains unknown, however, the supra-modal and modality-specific practice effect during cross-modal selective attention, and moreover whether the practice effect shows similar modality preferences as the visual dominance effect in the multisensory environment. To answer the above two questions, we adopted a cross-modal selective attention paradigm in conjunction with the hybrid fMRI design. Behaviorally, visual performance significantly improved while auditory performance remained constant with practice, indicating that visual attention more flexibly adapted behavior with practice than auditory attention. At the neural level, the practice effect was associated with decreasing neural activity in the frontoparietal executive network and increasing activity in the default mode network, which occurred independently of the modality attended, i.e., the supra-modal mechanisms. On the other hand, functional decoupling between the auditory and the visual system was observed with the progress of practice, which varied as a function of the modality attended. The auditory system was functionally decoupled with both the dorsal and ventral visual stream during auditory attention while was decoupled only with the ventral visual stream during visual attention. To efficiently suppress the irrelevant visual information with practice, auditory attention needs to additionally decouple the auditory system from the dorsal visual stream. The modality-specific mechanisms, together with the behavioral effect, thus support the visual dominance model in terms of the practice effect during cross-modal selective attention. Copyright © 2018 Elsevier Ltd. All rights reserved.

Vision in two cyprinid fish: implications for collective behavior

PubMed Central

Moore, Bret A.; Tyrrell, Luke P.; Fernández-Juricic, Esteban

2015-01-01

Many species of fish rely on their visual systems to interact with conspecifics and these interactions can lead to collective behavior. Individual-based models have been used to predict collective interactions; however, these models generally make simplistic assumptions about the sensory systems that are applied without proper empirical testing to different species. This could limit our ability to predict (and test empirically) collective behavior in species with very different sensory requirements. In this study, we characterized components of the visual system in two species of cyprinid fish known to engage in visually dependent collective interactions (zebrafish Danio rerio and golden shiner Notemigonus crysoleucas) and derived quantitative predictions about the positioning of individuals within schools. We found that both species had relatively narrow binocular and blind fields and wide visual coverage. However, golden shiners had more visual coverage in the vertical plane (binocular field extending behind the head) and higher visual acuity than zebrafish. The centers of acute vision (areae) of both species projected in the fronto-dorsal region of the visual field, but those of the zebrafish projected more dorsally than those of the golden shiner. Based on this visual sensory information, we predicted that: (a) predator detection time could be increased by >1,000% in zebrafish and >100% in golden shiners with an increase in nearest neighbor distance, (b) zebrafish schools would have a higher roughness value (surface area/volume ratio) than those of golden shiners, (c) and that nearest neighbor distance would vary from 8 to 20 cm to visually resolve conspecific striping patterns in both species. Overall, considering between-species differences in the sensory system of species exhibiting collective behavior could change the predictions about the positioning of individuals in the group as well as the shape of the school, which can have implications for group cohesion. We suggest that more effort should be invested in assessing the role of the sensory system in shaping local interactions driving collective behavior. PMID:26290783

Morphological and behavioral limit of visual resolution in temperate (Hippocampus abdominalis) and tropical (Hippocampus taeniopterus) seahorses.

PubMed

Lee, Hie Rin; O'Brien, Keely M Bumsted

2011-07-01

Seahorses are visually guided feeders that prey upon small fast-moving crustaceans. Seahorse habitats range from clear tropical to turbid temperate waters. How are seahorse retinae specialized to mediate vision in these diverse environments? Most species of seahorse have a specialization in their retina associated with acute vision, the fovea. The purpose of this study was to characterize the fovea of temperate Hippocampus abdominalis and tropical H. taeniopterus seahorses and to investigate their theoretical and behavioral limits of visual resolution. Their foveae were identified and photoreceptor (PR) and ganglion cell (GC) densities determined throughout the retina and topographically mapped. The theoretical limit of visual resolution was calculated using formulas taking into account lens radius and either cone PR or GC densities. Visual resolution was determined behaviorally using reactive distance. Both species possess a rod-free convexiclivate fovea. PR and GC densities were highest along the foveal slope, with a density decrease within the foveal center. Outside the fovea, there was a gradual density decrease towards the periphery. The theoretically calculated visual resolution on the foveal slope was poorer for H. abdominalis (5.25 min of arc) compared with H. taeniopterus (4.63 min of arc) based on PR density. Using GC density, H. abdominalis (9.81 min of arc) had a lower resolution compared with H. taeniopterus (9.04 min of arc). Behaviorally, H. abdominalis had a resolution limit of 1090.64 min of arc, while H. taeniopterus was much smaller, 692.86 min of arc. Although both species possess a fovea and the distribution of PR and GC is similar, H. taeniopterus has higher PR and GC densities on the foveal slope and better theoretical and behaviorally measured visual resolution compared to H. abdominalis. These data indicate that seahorses have a well-developed acute visual system, and tropical seahorses have higher visual resolution compared to temperate seahorses.

Cortical Modulation of Motor Control Biofeedback among the Elderly with High Fall Risk during a Posture Perturbation Task with Augmented Reality

PubMed Central

Chang, Chun-Ju; Yang, Tsui-Fen; Yang, Sai-Wei; Chern, Jen-Suh

2016-01-01

The cerebral cortex provides sensorimotor integration and coordination during motor control of daily functional activities. Power spectrum density based on electroencephalography (EEG) has been employed as an approach that allows an investigation of the spatial–temporal characteristics of neuromuscular modulation; however, the biofeedback mechanism associated with cortical activation during motor control remains unclear among elderly individuals. Thirty one community-dwelling elderly participants were divided into low fall-risk potential (LF) and high fall-risk potential (HF) groups based upon the results obtained from a receiver operating characteristic analysis of the ellipse area of the center of pressure. Electroencephalography (EEG) was performed while the participants stood on a 6-degree-of-freedom Stewart platform, which generated continuous perturbations and done either with or without the virtual reality scene. The present study showed that when there was visual stimulation and poor somatosensory coordination, a higher level of cortical response was activated in order to keep postural balance. The elderly participants in the LF group demonstrated a significant and strong correlation between postural-related cortical regions; however, the elderly individuals in the HF group did not show such a relationship. Moreover, we were able to clarify the roles of various brainwave bands functioning in motor control. Specifically, the gamma and beta bands in the parietal–occipital region facilitate the high-level cortical modulation and sensorimotor integration, whereas the theta band in the frontal–central region is responsible for mediating error detection during perceptual motor tasks. Finally, the alpha band is associated with processing visual challenges in the occipital lobe.With a variety of motor control demands, increment in brainwave band coordination is required to maintain postural stability. These investigations shed light on the cortical modulation of motor control among elderly participants with varying fall-risk potentials. The results suggest that, although elderly adults may be without neurological deficits, inefficient central modulation during challenging postural conditions could be an internal factor that contributes to the risk of fall. Furthermore, training that helps to improve coordinated sensorimotor integration may be a useful approach to reduce the risk of fall among elderly populations or when patients suffer from neurological deficits. PMID:27199732

The influence of multiple sensory impairments on functional balance and difficulty with falls among U.S. adults.

PubMed

Wilson, Samuel J; Garner, John C; Loprinzi, Paul D

2016-06-01

Studies have looked at the individual associations of sensory impairment on balance, but no population-based studies have examined their combined association on balance and difficulty with falls. Thus, the purpose of this study was to examine both the independent associations and combined associations of visual impairment, peripheral neuropathy, and self-reported hearing loss with the odds of reporting difficulty with falls and functional balance. Data from the 2003-2004 National Health and Nutrition Examination Survey were used. Vision and peripheral neuropathy were objectively measured, and hearing was self-reported. Balance testing consisted of a modified Romberg test. After exclusions, 1662 (40-85years of age) participants provided complete data on the study variables. Sensory impairment was associated with perceived difficulty of falls and functional balance. Participants who presented a single sensory impairment had 29% reduced odds of having functional balance (95% CI=0.54-0.93, p=0.01) and increased odds of reporting difficulty with falls by 61% (95% CI=0.99-2.60, p=0.05). Moreover, our multisensory models showed some evidence of a dose-response relationship, in that sensory impairment of multiple sensory systems was associated with worse balance (OR =0.59, CI=0.35-1.00, p=0.05) and perceived difficulty of falls (OR =5.02, 95% CI=1.99-12.66, p=0.002) when compared to those with less sensory impairment. Multiple sensory impairment is associated with significantly higher odds of both reporting difficulty with falls and balance dysfunction, which may lead to a subsequent fall, ultimately compromising the individual's health. Copyright © 2016 Elsevier Inc. All rights reserved.

The clinical utility of posturography.

PubMed

Visser, Jasper E; Carpenter, Mark G; van der Kooij, Herman; Bloem, Bastiaan R

2008-11-01

Postural instability and falls are common and devastating features of ageing and many neurological, visual, vestibular or orthopedic disorders. Current management of these problems is hampered by the subjective and variable nature of the available clinical balance measures. In this narrative review, we discuss the clinical utility of posturography as a more objective and quantitative measure of balance and postural instability, focusing on several areas where clinicians presently experience the greatest difficulties in managing their patients: (a) to make an appropriate differential diagnosis in patients presenting with falls or balance impairment; (b) to reliably identify those subjects who are at risk of falling; (c) to objectively and quantitatively document the outcome of therapeutic interventions; and (d) to gain a better pathophysiological understanding of postural instability and falls, as a basis for the development of improved treatment strategies to prevent falling. In each of these fields, posturography offers several theoretical advantages and, when applied correctly, provides a useful tool to gain a better understanding of pathophysiological mechanisms in patients with balance disorders, at the group level. However, based on the available evidence, none of the existing techniques is currently able to significantly influence the clinical decision making in individual patients. We critically review the shortcomings of posturography as it is presently used, and conclude with several recommendations for future research.

Uncovering Oscillations, Complexity, and Chaos in Chemical Kinetics Using Mathematica

NASA Astrophysics Data System (ADS)

Ferreira, M. M. C.; Ferreira, W. C., Jr.; Lino, A. C. S.; Porto, M. E. G.

1999-06-01

Unlike reactions with no peculiar temporal behavior, in oscillatory reactions concentrations can rise and fall spontaneously in a cyclic or disorganized fashion. In this article, the software Mathematica is used for a theoretical study of kinetic mechanisms of oscillating and chaotic reactions. A first simple example is introduced through a three-step reaction, called the Lotka model, which exhibits a temporal behavior characterized by damped oscillations. The phase plane method of dynamic systems theory is introduced for a geometric interpretation of the reaction kinetics without solving the differential rate equations. The equations are later numerically solved using the built-in routine NDSolve and the results are plotted. The next example, still with a very simple mechanism, is the Lotka-Volterra model reaction, which oscillates indefinitely. The kinetic process and rate equations are also represented by a three-step reaction mechanism. The most important difference between this and the former reaction is that the undamped oscillation has two autocatalytic steps instead of one. The periods of oscillations are obtained by using the discrete Fourier transform (DFT)-a well-known tool in spectroscopy, although not so common in this context. In the last section, it is shown how a simple model of biochemical interactions can be useful to understand the complex behavior of important biological systems. The model consists of two allosteric enzymes coupled in series and activated by its own products. This reaction scheme is important for explaining many metabolic mechanisms, such as the glycolytic oscillations in muscles, yeast glycolysis, and the periodic synthesis of cyclic AMP. A few of many possible dynamic behaviors are exemplified through a prototype glycolytic enzymatic reaction proposed by Decroly and Goldbeter. By simply modifying the initial concentrations, limit cycles, chaos, and birhythmicity are computationally obtained and visualized.

The Impact of Multiple Types of Child Maltreatment on Subsequent Risk Behaviors among Women during the Transition from Adolescence to Young Adulthood

ERIC Educational Resources Information Center

Hahm, Hyeouk Chris; Lee, Yoona; Ozonoff, Al; Van Wert, Michael J.

2010-01-01

The purpose of this study was to investigate how different types of child maltreatment, independently and collectively, impact a wide range of risk behaviors that fall into three domains: sexual risk behaviors, delinquency, and suicidality. Cumulative classification and Expanded Hierarchical Type (EHT) classification approaches were used to…

Effect of Certified Personal Trainer Services on Stage of Exercise Behavior and Exercise Mediators in Female College Students

ERIC Educational Resources Information Center

Fischer, Donald V.; Bryant, Jennifer

2008-01-01

Objective: The authors examined the effect of certified personal trainer services on exercise behavior by using the transtheoretical model of behavioral change. Participants: Female college students (n = 449) completed surveys during the first week (T1) and last week (T2) of the fall semester. Methods: Students receiving personal trainer services…

Infant Attention and Visual Preferences: Converging Evidence from Behavior, Event-Related Potentials, and Cortical Source Localization

ERIC Educational Resources Information Center

Reynolds, Greg D.; Courage, Mary L.; Richards, John E.

2010-01-01

In this study, we had 3 major goals. The 1st goal was to establish a link between behavioral and event-related potential (ERP) measures of infant attention and recognition memory. To assess the distribution of infant visual preferences throughout ERP testing, we designed a new experimental procedure that embeds a behavioral measure (paired…

Sensory system plasticity in a visually specialized, nocturnal spider.

PubMed

Stafstrom, Jay A; Michalik, Peter; Hebets, Eileen A

2017-04-21

The interplay between an animal's environmental niche and its behavior can influence the evolutionary form and function of its sensory systems. While intraspecific variation in sensory systems has been documented across distant taxa, fewer studies have investigated how changes in behavior might relate to plasticity in sensory systems across developmental time. To investigate the relationships among behavior, peripheral sensory structures, and central processing regions in the brain, we take advantage of a dramatic within-species shift of behavior in a nocturnal, net-casting spider (Deinopis spinosa), where males cease visually-mediated foraging upon maturation. We compared eye diameters and brain region volumes across sex and life stage, the latter through micro-computed X-ray tomography. We show that mature males possess altered peripheral visual morphology when compared to their juvenile counterparts, as well as juvenile and mature females. Matching peripheral sensory structure modifications, we uncovered differences in relative investment in both lower-order and higher-order processing regions in the brain responsible for visual processing. Our study provides evidence for sensory system plasticity when individuals dramatically change behavior across life stages, uncovering new avenues of inquiry focusing on altered reliance of specific sensory information when entering a new behavioral niche.

Sequence Diversity Diagram for comparative analysis of multiple sequence alignments.

PubMed

Sakai, Ryo; Aerts, Jan

2014-01-01

The sequence logo is a graphical representation of a set of aligned sequences, commonly used to depict conservation of amino acid or nucleotide sequences. Although it effectively communicates the amount of information present at every position, this visual representation falls short when the domain task is to compare between two or more sets of aligned sequences. We present a new visual presentation called a Sequence Diversity Diagram and validate our design choices with a case study. Our software was developed using the open-source program called Processing. It loads multiple sequence alignment FASTA files and a configuration file, which can be modified as needed to change the visualization. The redesigned figure improves on the visual comparison of two or more sets, and it additionally encodes information on sequential position conservation. In our case study of the adenylate kinase lid domain, the Sequence Diversity Diagram reveals unexpected patterns and new insights, for example the identification of subgroups within the protein subfamily. Our future work will integrate this visual encoding into interactive visualization tools to support higher level data exploration tasks.

Virtual reality stimuli for force platform posturography.

PubMed

Tossavainen, Timo; Juhola, Martti; Ilmari, Pyykö; Aalto, Heikki; Toppila, Esko

2002-01-01

People relying much on vision in the control of posture are known to have an elevated risk of falling. Dependence on visual control is an important parameter in the diagnosis of balance disorders. We have previously shown that virtual reality methods can be used to produce visual stimuli that affect balance, but suitable stimuli need to be found. In this study the effect of six different virtual reality stimuli on the balance of 22 healthy test subjects was evaluated using force platform posturography. According to the tests two of the stimuli have a significant effect on balance.

Image Processor

NASA Technical Reports Server (NTRS)

1989-01-01

Texas Instruments Programmable Remapper is a research tool used to determine how to best utilize the part of a patient's visual field still usable by mapping onto his field of vision with manipulated imagery. It is an offshoot of a NASA program for speeding up, improving the accuracy of pattern recognition in video imagery. The Remapper enables an image to be "pushed around" so more of it falls into the functional portions in the retina of a low vision person. It works at video rates, and researchers hope to significantly reduce its size and cost, creating a wearable prosthesis for visually impaired people.

The dependence of the CO2 removal efficiency of LiOH on humidity and mesh size. [in spacecraft life support systems

NASA Technical Reports Server (NTRS)

Davis, S. H.; Kissinger, L. D.

1978-01-01

The effect of humidity on the CO2 removal efficiency of small beds of anhydrous LiOH has been studied. Experimental data taken in this small bed system clearly show that there is an optimum humidity for beds loaded with LiOH from a single lot. The CO2 efficiency falls rapidly under dry conditions, but this behavior is approximately the same in all samples. The behavior of the bed under wet conditions is quite dependent on material size distribution. The presence of large particles in a sample can lead to rapid fall off in the CO2 efficiency as the humidity increases.

Cooling and solidification of liquid-metal drops in a gaseous atmosphere

NASA Technical Reports Server (NTRS)

Mccoy, J. K.; Markworth, A. J.; Collings, E. W.; Brodkey, R. S.

1992-01-01

The free fall of a liquid-metal drop, heat transfer from the drop to its environment, and solidification of the drop are described for both gaseous and vacuum atmospheres. A simple model, in which the drop is assumed to fall rectilinearly, with behavior like that of a rigid particle, is developed to describe cooling behavior. Recalescence of supercooled drops is assumed to occur instantaneously when a specified temperature is passed. The effects of solidification and experimental parameters on drop cooling are calculated and discussed. Major results include temperature as a function of time, and of drag, time to complete solidification, and drag as a function of the fraction of the drop solidified.

Density-Dependent Oviposition by Female Aedes albopictus (Diptera: Culicidae) Spreads Eggs Among Containers During the Summer but Accumulates Them in the Fall.

PubMed

Fonseca, D M; Kaplan, L R; Heiry, R A; Strickman, D

2015-07-01

When possible, oviparous females should deposit eggs in sites that maximize the future performance of their offspring. Therefore, studies of oviposition behavior may uncover parameters important to offspring fitness. Gravid female Aedes albopictus (Skuse) were given a choice of containers with leaf infusion or plain water, either open or with a cover with a small opening, and their behavior was compared under summer (long day, higher temperature) or fall (short day, lower temperature) regimes. Open containers with leaf infusion were always preferred, but over time, summer females expanded their choices to oviposit in all containers and follow-up experiments indicated that the number of eggs laid was inversely correlated to the number of eggs present. In contrast, fall females laying diapausing eggs that do not hatch until the spring, accumulated eggs in open containers with food resulting in high egg densities. Combined, these results demonstrate a seasonal shift that suggests either high winter egg mortality or safety in numbers. It also demonstrates that female Ae. albopictus change their behavior based on cues associated with expected added risk, which varies across time and space. The wide distribution of summer eggs across container types may contribute to the fast expansion of Ae. albopictus across its invasive range, but egg accumulation in the fall may be exploited for control. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Prismatic displacement effect of progressive multifocal glasses on reaction time and accuracy in elderly people.

PubMed

Ellison, Ashton C; Campbell, A John; Robertson, M Clare; Sanderson, Gordon F

2014-01-01

Multifocal glasses (bifocals, trifocals, and progressives) increase the risk of falling in elderly people, but how they do so is unclear. To explain why glasses with progressive addition lenses increase the risk of falls and whether this can be attributed to false projection, this study aimed to 1) map the prismatic displacement of a progressive lens, and 2) test whether this displacement impaired reaction time and accuracy. The reaction times of healthy ≥75-year-olds (31 participants) were measured when grasping for a bar and touching a black line. Participants performed each test twice, wearing their progressives and new, matched single vision (distance) glasses in random order. The line and bar targets were positioned according to the maximum and minimum prismatic displacement effect through the progressive lens, mapped using a focimeter. Progressive spectacle lenses have large areas of prismatic displacement in the central visual axis and edges. Reaction time was faster for progressives compared with single vision glasses with a centrally-placed horizontal grab bar (mean difference 101 ms, P=0.011 [repeated measures analysis]) and a horizontal black line placed 300 mm below center (mean difference 80 ms, P=0.007). There was no difference in accuracy between the two types of glasses. Older people appear to adapt to the false projection of progressives in the central visual axis. This adaptation means that swapping to new glasses or a large change in prescription may lead to a fall. Frequently updating glasses may be more beneficial.

Cerebellum and cognition in multiple sclerosis: the fall status matters.

PubMed

Kalron, Alon; Allali, Gilles; Achiron, Anat

2018-04-01

Cerebellar volume has been linked with cognitive performances in MS; however, the association in terms of fall status has never been compared. Therefore, the objective of the current study was to compare cognitive performance with cerebellar volume between MS fallers and non-fallers. The cross-sectional study included 140 PwMS (96 women). MRI volumetric analysis was based on the FreeSurfer image analysis suite. Volumes of the cerebellar gray and white matter were identified as the region of interest. Cognitive function included scores obtained from a computerized cognitive battery of tests. The sample was divided into fallers and non-fallers. MS fallers demonstrated a lower global cognitive performance and reduced gray and white matter cerebellar volumes compared to non-fallers. A significant association was found between total gray and white matter cerebellar volume and visual spatial subdomain (P value = 0.044 and 0.032, respectively) in the non-fallers group. The association remained significant after controlling for the total cranial volume and neurological disability (P value = 0.026 and 0.047, respectively). A relationship was found between the visual spatial score and the left gray matter cerebellum volume; R 2  = 0.44, P value = 0.021. We believe that a unique relationship exists between the cerebellum structure and cognitive processing according to fall history in PwMS and should be considered when investigating the association between brain functioning and cognitive performances in MS.

Segregating the significant from the mundane on a moment-to-moment basis via direct and indirect amygdala contributions

PubMed Central

Lim, Seung-Lark; Padmala, Srikanth; Pessoa, Luiz

2009-01-01

If the amygdala is involved in shaping perceptual experience when affectively significant visual items are encountered, responses in this structure should be correlated with both visual cortex responses and behavioral reports. Here, we investigated how affective significance shapes visual perception during an attentional blink paradigm combined with aversive conditioning. Behaviorally, following aversive learning, affectively significant scenes (CS+) were better detected than neutral (CS−) ones. In terms of mean brain responses, both amygdala and visual cortical responses were stronger during CS+ relative to CS− trials. Increased brain responses in these regions were associated with improved behavioral performance across participants and followed a mediation-like pattern. Importantly, the mediation pattern was observed in a trial-by-trial analysis, revealing that the specific pattern of trial-by-trial variability in brain responses was closely related to single-trial behavioral performance. Furthermore, the influence of the amygdala on visual cortical responses was consistent with a mediation, although partial, via frontal brain regions. Our results thus suggest that affective significance potentially determines the fate of a visual item during competitive interactions by enhancing sensory processing through both direct and indirect paths. In so doing, the amygdala helps separate the significant from the mundane. PMID:19805383

Scopolamine effects on visual discrimination: modifications related to stimulus control

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

Evans, H.L.

1975-01-01

Stumptail monkeys (Macaca arctoides) performed a discrete trial, three-choice visual discrimination. The discrimination behavior was controlled by the shape of the visual stimuli. Strength of the stimuli in controlling behavior was systematically related to a physical property of the stimuli, luminance. Low luminance provided weak control, resulting in a low accuracy of discrimination, a low response probability and maximal sensitivity to scopolamine (7.5-60 ..mu..g/kg). In contrast, high luminance provided strong control of behavior and attenuated the effects of scopolamine. Methylscopolamine had no effect in doses of 30 to 90 ..mu..g/kg. Scopolamine effects resembled the effects of reducing stimulus control inmore » undrugged monkeys. Since behavior under weak control seems to be especially sensitive to drugs, manipulations of stimulus control may be particularly useful whenever determination of the minimally-effective dose is important, as in behavioral toxicology. Present results are interpreted as specific visual effects of the drug, since nonsensory factors such as base-line response rate, reinforcement schedule, training history, motor performance and motivation were controlled. Implications for state-dependent effects of drugs are discussed.« less

Epidemiology of falls in older adults in Texas.

PubMed

Alamgir, Hasanat; Wong, Nicole J; Hu, Yueha; Yu, Mo; Marshall, Amanda; Yu, Shicheng

2015-02-01

The expected increase in the US older adult population implies an increased risk of fall-related injury among these individuals. We describe the epidemiology of fall morbidity among older adults in Texas, a large US state with a diverse population base. Texas Behavioral Risk Factor Surveillance System 2010 data were analyzed. The falls outcome was defined as falling: any fall in the past 3 months and a serious fall: a fall resulting in limited activities for at least 1 day or requiring medical attention. A total of 5996 subjects were included in this analysis; 17.6% (n = 1055) reported falling 1 to 5 times in the previous 3 months, and 361 (6%) experienced serious falls. Risk of falling had a significant positive association among respondents who rated their general health as fair to poor (relative risk [RR] 2.39, 95% confidence interval [CI] 1.55-3.68) and a negative association for those who reported regular physical activity (RR 0.59, 95% CI 0.42-0.82). A similar model examined the risk of serious falls and found statistically positive associations in respondents who reported fair or poor general health (RR 3.29, 95% CI 2.00-5.43). Negative associations were found for those who reported regular physical activity (RR 0.56, 95% CI 0.38-0.83) and for men (RR 0.62, 95% CI 0.39-0.98). No statistically significant correlations for either of the fall outcomes were found with residence, obesity, education, income, age, ethnicity, employment, marital status, diabetes mellitus, or cardiovascular disease. Interventions aimed at the prevention of falls should focus on maintaining and improving general health and promoting physical activity among older adults.

Reduction in Fall Rate in Dementia Managed Care Through Video Incident Review: Pilot Study

PubMed Central

Netscher, George; Agrawal, Pulkit; Tabb Noyce, Lynn; Bayen, Alexandre

2017-01-01

Background Falls of individuals with dementia are frequent, dangerous, and costly. Early detection and access to the history of a fall is crucial for efficient care and secondary prevention in cognitively impaired individuals. However, most falls remain unwitnessed events. Furthermore, understanding why and how a fall occurred is a challenge. Video capture and secure transmission of real-world falls thus stands as a promising assistive tool. Objective The objective of this study was to analyze how continuous video monitoring and review of falls of individuals with dementia can support better quality of care. Methods A pilot observational study (July-September 2016) was carried out in a Californian memory care facility. Falls were video-captured (24×7), thanks to 43 wall-mounted cameras (deployed in all common areas and in 10 out of 40 private bedrooms of consenting residents and families). Video review was provided to facility staff, thanks to a customized mobile device app. The outcome measures were the count of residents’ falls happening in the video-covered areas, the acceptability of video recording, the analysis of video review, and video replay possibilities for care practice. Results Over 3 months, 16 falls were video-captured. A drop in fall rate was observed in the last month of the study. Acceptability was good. Video review enabled screening for the severity of falls and fall-related injuries. Video replay enabled identifying cognitive-behavioral deficiencies and environmental circumstances contributing to the fall. This allowed for secondary prevention in high-risk multi-faller individuals and for updated facility care policies regarding a safer living environment for all residents. Conclusions Video monitoring offers high potential to support conventional care in memory care facilities. PMID:29042342

Stroke survivors' views and experiences on impact of visual impairment.

PubMed

Rowe, Fiona J

2017-09-01

We sought to determine stroke survivors' views on impact of stroke-related visual impairment to quality of life. Stroke survivors with visual impairment, more than 1 year post stroke onset, were recruited. Semistructured biographical narrative interviews were audio-recorded and transcribed verbatim. A thematic approach to analysis of the qualitative data was adopted. Transcripts were systematically coded using NVivo10 software. Thirty-five stroke survivors were interviewed across the UK: 16 females, 19 males; aged 20-75 years at stroke onset. Five qualitative themes emerged: "Formal care," "Symptoms and self," "Adaptations," "Daily life," and "Information." Where visual problems existed, they were often not immediately recognized as part of the stroke syndrome and attributed to other causes such as migraine. Many participants did not receive early vision assessment or treatment for their visual problems. Visual problems included visual field loss, double vision, and perceptual problems. Impact of visual problems included loss in confidence, being a burden to others, increased collisions/accidents, and fear of falling. They made many self-identified adaptations to compensate for visual problems: magnifiers, large print, increased lighting, use of white sticks. There was a consistent lack of support and provision of information about visual problems. Poststroke visual impairment causes considerable impact to daily life which could be substantially improved by simple measures including early formal visual assessment, management and advice on adaptive strategies and self-management options. Improved education about poststroke visual impairment for the public and clinicians could aid earlier diagnosis of visual impairments.

Figure–ground discrimination behavior in Drosophila. I. Spatial organization of wing-steering responses

PubMed Central

Fox, Jessica L.; Aptekar, Jacob W.; Zolotova, Nadezhda M.; Shoemaker, Patrick A.; Frye, Mark A.

2014-01-01

The behavioral algorithms and neural subsystems for visual figure–ground discrimination are not sufficiently described in any model system. The fly visual system shares structural and functional similarity with that of vertebrates and, like vertebrates, flies robustly track visual figures in the face of ground motion. This computation is crucial for animals that pursue salient objects under the high performance requirements imposed by flight behavior. Flies smoothly track small objects and use wide-field optic flow to maintain flight-stabilizing optomotor reflexes. The spatial and temporal properties of visual figure tracking and wide-field stabilization have been characterized in flies, but how the two systems interact spatially to allow flies to actively track figures against a moving ground has not. We took a systems identification approach in flying Drosophila and measured wing-steering responses to velocity impulses of figure and ground motion independently. We constructed a spatiotemporal action field (STAF) – the behavioral analog of a spatiotemporal receptive field – revealing how the behavioral impulse responses to figure tracking and concurrent ground stabilization vary for figure motion centered at each location across the visual azimuth. The figure tracking and ground stabilization STAFs show distinct spatial tuning and temporal dynamics, confirming the independence of the two systems. When the figure tracking system is activated by a narrow vertical bar moving within the frontal field of view, ground motion is essentially ignored despite comprising over 90% of the total visual input. PMID:24198267

Visual Navigation during Colony Emigration by the Ant Temnothorax rugatulus

PubMed Central

Bowens, Sean R.; Glatt, Daniel P.; Pratt, Stephen C.

2013-01-01

Many ants rely on both visual cues and self-generated chemical signals for navigation, but their relative importance varies across species and context. We evaluated the roles of both modalities during colony emigration by Temnothorax rugatulus. Colonies were induced to move from an old nest in the center of an arena to a new nest at the arena edge. In the midst of the emigration the arena floor was rotated 60°around the old nest entrance, thus displacing any substrate-bound odor cues while leaving visual cues unchanged. This manipulation had no effect on orientation, suggesting little influence of substrate cues on navigation. When this rotation was accompanied by the blocking of most visual cues, the ants became highly disoriented, suggesting that they did not fall back on substrate cues even when deprived of visual information. Finally, when the substrate was left in place but the visual surround was rotated, the ants' subsequent headings were strongly rotated in the same direction, showing a clear role for visual navigation. Combined with earlier studies, these results suggest that chemical signals deposited by Temnothorax ants serve more for marking of familiar territory than for orientation. The ants instead navigate visually, showing the importance of this modality even for species with small eyes and coarse visual acuity. PMID:23671713

Preventing Challenging Behaviors in Preschool: Effective Strategies for Classroom Teachers

ERIC Educational Resources Information Center

Coleman, Janelle C.; Crosby, Megan G.; Irwin, Heather K.; Dennis, Lindsay R.; Simpson, Cynthia G.; Rose, Chad A.

2013-01-01

This article provides practical strategies and techniques that early childhood educators can implement in their classrooms to effectively manage challenging behaviors. The specific strategies addressed fall under the following categories: (a) classroom management, (b) reinforcement, and (c) communication. Suggestions are made for how parents can…

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-related activity avoidance is reported among those that do not fall and already in mild PD-stages (HY I-II). Although further studies are needed, our findings indicate that fall-related activity avoidance needs to be addressed early in order to prevent sedentary behavior and participation restrictions.

FRAT-up, a Web-based fall-risk assessment tool for elderly people living in the community.

PubMed

Cattelani, Luca; Palumbo, Pierpaolo; Palmerini, Luca; Bandinelli, Stefania; Becker, Clemens; Chesani, Federico; Chiari, Lorenzo

2015-02-18

About 30% of people over 65 are subject to at least one unintentional fall a year. Fall prevention protocols and interventions can decrease the number of falls. To be effective, a prevention strategy requires a prior step to evaluate the fall risk of the subjects. Despite extensive research, existing assessment tools for fall risk have been insufficient for predicting falls. The goal of this study is to present a novel web-based fall-risk assessment tool (FRAT-up) and to evaluate its accuracy in predicting falls, within a context of community-dwelling persons aged 65 and up. FRAT-up is based on the assumption that a subject's fall risk is given by the contribution of their exposure to each of the known fall-risk factors. Many scientific studies have investigated the relationship between falls and risk factors. The majority of these studies adopted statistical approaches, usually providing quantitative information such as odds ratios. FRAT-up exploits these numerical results to compute how each single factor contributes to the overall fall risk. FRAT-up is based on a formal ontology that enlists a number of known risk factors, together with quantitative findings in terms of odds ratios. From such information, an automatic algorithm generates a rule-based probabilistic logic program, that is, a set of rules for each risk factor. The rule-based program takes the health profile of the subject (in terms of exposure to the risk factors) and computes the fall risk. A Web-based interface allows users to input health profiles and to visualize the risk assessment for the given subject. FRAT-up has been evaluated on the InCHIANTI Study dataset, a representative population-based study of older persons living in the Chianti area (Tuscany, Italy). We compared reported falls with predicted ones and computed performance indicators. The obtained area under curve of the receiver operating characteristic was 0.642 (95% CI 0.614-0.669), while the Brier score was 0.174. The Hosmer-Lemeshow test indicated statistical significance of miscalibration. FRAT-up is a web-based tool for evaluating the fall risk of people aged 65 or up living in the community. Validation results of fall risks computed by FRAT-up show that its performance is comparable to externally validated state-of-the-art tools. A prototype is freely available through a web-based interface. ClinicalTrials.gov NCT01331512 (The InChianti Follow-Up Study); http://clinicaltrials.gov/show/NCT01331512 (Archived by WebCite at http://www.webcitation.org/6UDrrRuaR).

The Effects of Training on a Young Child with Cortical Visual Impairment: An Exploratory Study.

ERIC Educational Resources Information Center

Lueck, Amanda Hall; Dornbusch, Helen; Hart, Jeri

1999-01-01

This exploratory study investigated the effects of the components of visual environmental management, visual skills training, and visually dependent task training on the performance of visual behaviors of a toddler with multiple disabilities including cortical visual impairment. Training components were implemented by the mother during daily…

Spatiotemporal data visualisation for homecare monitoring of elderly people.

PubMed

Juarez, Jose M; Ochotorena, Jose M; Campos, Manuel; Combi, Carlo

2015-10-01

Elderly people who live alone can be assisted by home monitoring systems that identify risk scenarios such as falls, fatigue symptoms or burglary. Given that these systems have to manage spatiotemporal data, human intervention is required to validate automatic alarms due to the high number of false positives and the need for context interpretation. The goal of this work was to provide tools to support human action, to identify such potential risk scenarios based on spatiotemporal data visualisation. We propose the MTA (multiple temporal axes) model, a visual representation of temporal information of the activity of a single person at different locations. The main goal of this model is to visualize the behaviour of a person in their home, facilitating the identification of health-risk scenarios and repetitive patterns. We evaluate the model's insight capacity compared with other models using a standard evaluation protocol. We also test its practical suitability of the MTA graphical model in a commercial home monitoring system. In particular, we implemented 8VISU, a visualization tool based on MTA. MTA proved to be more than 90% accurate in identify non-risk scenarios, independently of the length of the record visualised. When the spatial complexity was increased (e.g. number of rooms) the model provided good accuracy form up to 5 rooms. Therefore, user preferences and user performance seem to be balanced. Moreover, it also gave high sensitivity levels (over 90%) for 5-8 rooms. Fall is the most recurrent incident for elderly people. The MTA model outperformed the other models considered in identifying fall scenarios (66% of correctness) and was the second best for burglary and fatigue scenarios (36% of correctness). Our experiments also confirm the hypothesis that cyclic models are the most suitable for fatigue scenarios, the Spiral and MTA models obtaining most positive identifications. In home monitoring systems, spatiotemporal visualization is a useful tool for identifying risk and preventing home accidents in elderly people living alone. The MTA model helps the visualisation in different stages of the temporal data analysis process. In particular, its explicit representation of space and movement is useful for identifying potential scenarios of risk, while the spiral structure can be used for the identification of recurrent patterns. The results of the experiments and the experience using the visualization tool 8VISU proof the potential of the MTA graphical model to mine temporal data and to support caregivers using home monitoring infrastructures. Copyright © 2015 Elsevier B.V. All rights reserved.

Development of Visual Motion Perception for Prospective Control: Brain and Behavioral Studies in Infants

PubMed Central

Agyei, Seth B.; van der Weel, F. R. (Ruud); van der Meer, Audrey L. H.

2016-01-01

During infancy, smart perceptual mechanisms develop allowing infants to judge time-space motion dynamics more efficiently with age and locomotor experience. This emerging capacity may be vital to enable preparedness for upcoming events and to be able to navigate in a changing environment. Little is known about brain changes that support the development of prospective control and about processes, such as preterm birth, that may compromise it. As a function of perception of visual motion, this paper will describe behavioral and brain studies with young infants investigating the development of visual perception for prospective control. By means of the three visual motion paradigms of occlusion, looming, and optic flow, our research shows the importance of including behavioral data when studying the neural correlates of prospective control. PMID:26903908

Oculometric Assessment of Dynamic Visual Processing

NASA Technical Reports Server (NTRS)

Liston, Dorion Bryce; Stone, Lee

2014-01-01

Eye movements are the most frequent (3 per second), shortest-latency (150-250 ms), and biomechanically simplest (1 joint, no inertial complexities) voluntary motor behavior in primates, providing a model system to assess sensorimotor disturbances arising from trauma, fatigue, aging, or disease states (e.g., Diefendorf and Dodge, 1908). We developed a 15-minute behavioral tracking protocol consisting of randomized stepramp radial target motion to assess several aspects of the behavioral response to dynamic visual motion, including pursuit initiation, steadystate tracking, direction-tuning, and speed-tuning thresholds. This set of oculomotor metrics provide valid and reliable measures of dynamic visual performance (Stone and Krauzlis, 2003; Krukowski and Stone, 2005; Stone et al, 2009; Liston and Stone, 2014), and may prove to be a useful assessment tool for functional impairments of dynamic visual processing.

Visual exploration and analysis of human-robot interaction rules

NASA Astrophysics Data System (ADS)

Zhang, Hui; Boyles, Michael J.

2013-01-01

We present a novel interaction paradigm for the visual exploration, manipulation and analysis of human-robot interaction (HRI) rules; our development is implemented using a visual programming interface and exploits key techniques drawn from both information visualization and visual data mining to facilitate the interaction design and knowledge discovery process. HRI is often concerned with manipulations of multi-modal signals, events, and commands that form various kinds of interaction rules. Depicting, manipulating and sharing such design-level information is a compelling challenge. Furthermore, the closed loop between HRI programming and knowledge discovery from empirical data is a relatively long cycle. This, in turn, makes design-level verification nearly impossible to perform in an earlier phase. In our work, we exploit a drag-and-drop user interface and visual languages to support depicting responsive behaviors from social participants when they interact with their partners. For our principal test case of gaze-contingent HRI interfaces, this permits us to program and debug the robots' responsive behaviors through a graphical data-flow chart editor. We exploit additional program manipulation interfaces to provide still further improvement to our programming experience: by simulating the interaction dynamics between a human and a robot behavior model, we allow the researchers to generate, trace and study the perception-action dynamics with a social interaction simulation to verify and refine their designs. Finally, we extend our visual manipulation environment with a visual data-mining tool that allows the user to investigate interesting phenomena such as joint attention and sequential behavioral patterns from multiple multi-modal data streams. We have created instances of HRI interfaces to evaluate and refine our development paradigm. As far as we are aware, this paper reports the first program manipulation paradigm that integrates visual programming interfaces, information visualization, and visual data mining methods to facilitate designing, comprehending, and evaluating HRI interfaces.

The influence of an overactive bladder on falling: a study of females aged 40 and older in the community.

PubMed

Moon, Seung-Jin; Kim, Yong Tae; Lee, Tchun Yong; Moon, Hongsang; Kim, Mi Jung; Kim, Shin Ah; Choi, Bo Youl

2011-03-01

An overactive bladder (OAB) affects a person's quality of life. Patients who suffer from OAB run to the toilet frequently to prevent incontinence, and this behavior increases their risk of falling and fear of falling. This study evaluated the influence of OAB on falls and concern about falling in females aged 40 and over living in urban and rural communities. We conducted a population-based cohort study using King's Health Questionnaire (KHQ), the Korean version of Falls Efficacy Scale-International (KFES-I) and a questionnaire regarding falls, in females aged 40 and over in Guri city and Yangpyeong county. The data from 514 responders were analyzed. The definition of OAB was 'moderately' or 'a lot' of urgency, or urge incontinence in KHQ. Falls was defined as experience of falls in the last year. High fear of falling was defined as a score of 24 or over in KFES-I. The factors were analyzed by the exact chi-square test and Student's t-test. The multivariate logistic regression model was adopted in order to examine the effects of OAB on falls and concern about falling. Of the 514 responders, 98 fitted the criterion of OAB. Eighty-nine (17.3%) of the responders had experienced falls in the last year: twenty-seven (27.5%) in the group with OAB and 62 (14.9%) in the group without OAB. There was a significant association between falls and OAB (odds ratio [OR], 1.76; 95% confidence interval [CI], 1.00 to 3.08; P=0.0485), and between high fear of falling and OAB (OR, 2.72; 95% CI, 1.42 to 5.20; P=0.0024). Urgency and symptoms of urge incontinence increase the risk of falls in women aged 40 or older in the community. Early diagnosis and proper treatment may prevent falls and improve quality of life in OAB patients.

The Influence of an Overactive Bladder on Falling: A Study of Females Aged 40 and Older in the Community

PubMed Central

Moon, Seung-Jin; Kim, Yong Tae; Lee, Tchun Yong; Kim, Mi Jung; Kim, Shin Ah; Choi, Bo Youl

2011-01-01

Purpose An overactive bladder (OAB) affects a person's quality of life. Patients who suffer from OAB run to the toilet frequently to prevent incontinence, and this behavior increases their risk of falling and fear of falling. This study evaluated the influence of OAB on falls and concern about falling in females aged 40 and over living in urban and rural communities. Methods We conducted a population-based cohort study using King's Health Questionnaire (KHQ), the Korean version of Falls Efficacy Scale-International (KFES-I) and a questionnaire regarding falls, in females aged 40 and over in Guri city and Yangpyeong county. The data from 514 responders were analyzed. The definition of OAB was 'moderately' or 'a lot' of urgency, or urge incontinence in KHQ. Falls was defined as experience of falls in the last year. High fear of falling was defined as a score of 24 or over in KFES-I. The factors were analyzed by the exact chi-square test and Student's t-test. The multivariate logistic regression model was adopted in order to examine the effects of OAB on falls and concern about falling. Results Of the 514 responders, 98 fitted the criterion of OAB. Eighty-nine (17.3%) of the responders had experienced falls in the last year: twenty-seven (27.5%) in the group with OAB and 62 (14.9%) in the group without OAB. There was a significant association between falls and OAB (odds ratio [OR], 1.76; 95% confidence interval [CI], 1.00 to 3.08; P=0.0485), and between high fear of falling and OAB (OR, 2.72; 95% CI, 1.42 to 5.20; P=0.0024). Conclusions Urgency and symptoms of urge incontinence increase the risk of falls in women aged 40 or older in the community. Early diagnosis and proper treatment may prevent falls and improve quality of life in OAB patients. PMID:21468286

Designing sound and visual components for enhancement of urban soundscapes.

PubMed

Hong, Joo Young; Jeon, Jin Yong

2013-09-01

The aim of this study is to investigate the effect of audio-visual components on environmental quality to improve soundscape. Natural sounds with road traffic noise and visual components in urban streets were evaluated through laboratory experiments. Waterfall and stream water sounds, as well as bird sounds, were selected to enhance the soundscape. Sixteen photomontages of a streetscape were constructed in combination with two types of water features and three types of vegetation which were chosen as positive visual components. The experiments consisted of audio-only, visual-only, and audio-visual conditions. The preferences and environmental qualities of the stimuli were evaluated by a numerical scale and 12 pairs of adjectives, respectively. The results showed that bird sounds were the most preferred among the natural sounds, while the sound of falling water was found to degrade the soundscape quality when the road traffic noise level was high. The visual effects of vegetation on aesthetic preference were significant, but those of water features relatively small. It was revealed that the perceptual dimensions of the environment were different from the noise levels. Particularly, the acoustic comfort factor related to soundscape quality considerably influenced preference for the overall environment at a higher level of road traffic noise.

Visual communication stimulates reproduction in Nile tilapia, Oreochromis niloticus (L.).

PubMed

Castro, A L S; Gonçalves-de-Freitas, E; Volpato, G L; Oliveira, C

2009-04-01

Reproductive fish behavior is affected by male-female interactions that stimulate physiological responses such as hormonal release and gonad development. During male-female interactions, visual and chemical communication can modulate fish reproduction. The aim of the present study was to test the effect of visual and chemical male-female interaction on the gonad development and reproductive behavior of the cichlid fish Nile tilapia, Oreochromis niloticus (L.). Fifty-six pairs were studied after being maintained for 5 days under one of the four conditions (N = 14 for each condition): 1) visual contact (V); 2) chemical contact (Ch); 3) chemical and visual contact (Ch+V); 4) no sensory contact (Iso) - males and females isolated. We compared the reproductive behavior (nesting, courtship and spawning) and gonadosomatic index (GSI) of pairs of fish under all four conditions. Visual communication enhanced the frequency of courtship in males (mean +/- SEM; V: 24.79 +/- 3.30, Ch+V: 20.74 +/- 3.09, Ch: 0.1 +/- 0.07, Iso: 4.68 +/- 1.26 events/30 min; P < 0.05, two-way ANOVA with LSD post hoc test), induced spawning in females (3 spawning in V and also 3 in Ch+V condition), and increased GSI in males (mean +/- SEM; V: 1.39 +/- 0.08, Ch+V: 1.21 +/- 0.08, Ch: 1.04 +/- 0.07, Iso: 0.82 +/- 0.07%; P < 0.05, two-way ANOVA with LSD post hoc test). Chemical communication did not affect the reproductive behavior of pairs nor did it enhance the effects of visual contact. Therefore, male-female visual communication is an effective cue, which stimulates reproduction among pairs of Nile tilapia.

Does the range of IMF affect rise and fall trend in fragmentation?

NASA Astrophysics Data System (ADS)

Sharma, Sakshi; Kumar, Rohit; Puri, Rajeev K.

2018-05-01

We study the rise and fall behavior in the multiplicity of intermediate mass fragments produced in the asymmetric reactions of 36S+ 198Pt using isospin-dependent quantum molecular dynamics model. We use different definitions of intermediate mass fragments according to various experimental studies. We find that the use of one or the other definition of intermediate mass fragments does not alter results significantly.

Deconstructing anti-harm-reduction metaphors; mortality risk from falls and other traumatic injuries compared to smokeless tobacco use.

PubMed

Phillips, Carl V; Guenzel, Brian; Bergen, Paul

2006-04-18

Anti-harm-reduction advocates sometimes resort to pseudo-analogies to ridicule harm reduction. Those opposed to the use of smokeless tobacco as an alternative to smoking sometimes suggest that the substitution would be like jumping from a 3 story building rather than 10 story, or like shooting yourself in the foot rather than the head. These metaphors are grossly inappropriate for several reasons, notably including the fact that they are misleading about the actual risk levels. Based on the available literature on mortality from falls, we estimate that smoking presents a mortality risk similar to a fall of about 4 stories, while mortality risk from smokeless tobacco is no worse than that from an almost certainly non-fatal fall from less than 2 stories. Other metaphors are similarly misleading. These metaphors, like other false and misleading anti-harm-reduction statements are inherently unethical attempts to prevent people from learning accurate health information. Moreover, they implicitly provide bad advice about health behavior priorities and are intended to persuade people to stick with a behavior that is more dangerous than an available alternative. Finally, the metaphors exhibit a flippant tone that seems inappropriate for a serious discussion of health science.

Body posture differentially impacts on visual attention towards tool, graspable, and non-graspable objects.

PubMed

Ambrosini, Ettore; Costantini, Marcello

2017-02-01

Viewed objects have been shown to afford suitable actions, even in the absence of any intention to act. However, little is known as to whether gaze behavior (i.e., the way we simply look at objects) is sensitive to action afforded by the seen object and how our actual motor possibilities affect this behavior. We recorded participants' eye movements during the observation of tools, graspable and ungraspable objects, while their hands were either freely resting on the table or tied behind their back. The effects of the observed object and hand posture on gaze behavior were measured by comparing the actual fixation distribution with that predicted by 2 widely supported models of visual attention, namely the Graph-Based Visual Saliency and the Adaptive Whitening Salience models. Results showed that saliency models did not accurately predict participants' fixation distributions for tools. Indeed, participants mostly fixated the action-related, functional part of the tools, regardless of its visual saliency. Critically, the restriction of the participants' action possibility led to a significant reduction of this effect and significantly improved the model prediction of the participants' gaze behavior. We suggest, first, that action-relevant object information at least in part guides gaze behavior. Second, postural information interacts with visual information to the generation of priority maps of fixation behavior. We support the view that the kind of information we access from the environment is constrained by our readiness to act. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Behavioral, semiochemical and androgen responses by male giant pandas to the olfactory sexual receptivity cues of females.

PubMed

Wilson, Abbey E; Sparks, Darrell L; Knott, Katrina K; Kouba, Andrew J; Willard, Scott; Brown, Ashli

2018-07-01

Male giant pandas identify female sexual receptivity through the detection of olfactory cues in estrous urine. However, it is yet unknown which specific days of the female estrous cycle may provoke male sexual-social responses and a physiological readiness to mate. We hypothesized that female urine from specific days of the estrous cycle will be positively associated with specific changes in male behaviors, urinary semiochemical production, and steroidogenic activity. Experimental simultaneous choice trials were conducted in captivity with four male giant pandas during the spring breeding season and during fall. Male interest was determined by a behavioral preference toward peri-estrual urine collected from a specific day of the estrous cycle encompassing proestrus (Day -13, Day -6, Day -3, Day -2), estrus (Day -1 and Day 0), and metestrus (Day four and Day nine) over that of anestrous urine. Provocation of male sexual motivation was examined by changes in urinary semiochemical composition and urinary androgen concentrations. During the spring, male investigative behaviors indicated a preference for Day -13, Day -3 and Day 0 urine over anestrous urine, while no significant preferences for estrous urine could be detected during fall. The relative abundance of only three compounds in male urine were significantly higher above baseline values after males were exposed to peri-estrual urine during spring; whereas 34 compounds significantly increased in the fall. Similarly, androgen concentrations increased above baseline in only two out of four males during spring, while all males had elevated androgen concentrations after exposure to Day -3 urine during the fall. Our results suggest that peri-estrual urine from Day -13, Day -3, and Day 0 elicited the greatest duration of male investigation, changes in the semiochemical profile, and elevations in androgen levels. These data suggest that managers should incorporate a combination of behavioral, semiochemical, and endocrinological assessment of males in the reproductive management of giant pandas to determine impending ovulation and pinpoint the best time for male-female introductions and artificial inseminations. Copyright © 2018 Elsevier Inc. All rights reserved.

Etiology of Drinking and Driving among Adolescents: Implications for Primary Prevention.

ERIC Educational Resources Information Center

Klepp, Knut-Inge; And Others

1991-01-01

A survey of 1,482 high school students in spring and fall 1986 resulted in confirmation of the Problem Behavior Theory as a predictor of drinking and driving among adolescents. Environmental, behavioral, and demographic factors account for 50 percent of the variance in drinking and driving. (SK)

Drug-Facilitated Sexual Assault: College Women's Risk Perception and Behavioral Choices

ERIC Educational Resources Information Center

Crawford, Emily; Wright, Margaret O'Dougherty; Birchmeier, Zachary

2008-01-01

Objective: The authors investigated relationships among prior victimization, risk perceptions, and behavioral choices in responding to drug-facilitated sexual assault in a college party where alcohol is available. Participants and Methods: From fall 2003 to spring 2004, over 400 female undergraduates rated risk perception following an acquaintance…

Getting around when you're just getting by : the travel behavior and transportation expenditures of low-income adults.

DOT National Transportation Integrated Search

2011-01-01

How much do people with limited resources pay for cars, public transit, and other means of travel? How does their transportation behavior change during periods of falling employment and rising fuel prices? This research uses in-depth interviews with ...

Drunkorexia: Understanding the Co-Occurrence of Alcohol Consumption and Eating/Exercise Weight Management Behaviors

ERIC Educational Resources Information Center

Barry, Adam E.; Piazza-Gardner, Anna K.

2012-01-01

Objective: Examine the co-occurrence of alcohol consumption, physical activity, and disordered eating behaviors via a drunkorexia perspective. Participants: Nationally representative sample (n = 22,488) of college students completing the Fall 2008 National College Health Assessment. Methods: Hierarchical logistic regression was employed to…

Delirium in the geriatric unit: proton-pump inhibitors and other risk factors.

PubMed

Otremba, Iwona; Wilczyński, Krzysztof; Szewieczek, Jan

2016-01-01

Delirium remains a major nosocomial complication of hospitalized elderly. Predictive models for delirium may be useful for identification of high-risk patients for implementation of preventive strategies. Evaluate specific factors for development of delirium in a geriatric ward setting. Prospective cross-sectional study comprised 675 consecutive patients aged 79.2±7.7 years (66% women and 34% men), admitted to the subacute geriatric ward of a multiprofile university hospital after exclusion of 113 patients treated with antipsychotic medication because of behavioral disorders before admission. Comprehensive geriatric assessments including a structured interview, physical examination, geriatric functional assessment, blood sampling, ECG, abdominal ultrasound, chest X-ray, Confusion Assessment Method for diagnosis of delirium, Delirium-O-Meter to assess delirium severity, Richmond Agitation-Sedation Scale to assess sedation or agitation, visual analog scale and Doloplus-2 scale to assess pain level were performed. Multivariate logistic regression analysis revealed five independent factors associated with development of delirium in geriatric inpatients: transfer between hospital wards (odds ratio [OR] =2.78; confidence interval [CI] =1.54-5.01; P=0.001), preexisting dementia (OR =2.29; CI =1.44-3.65; P<0.001), previous delirium incidents (OR =2.23; CI =1.47-3.38; P<0.001), previous fall incidents (OR =1.76; CI =1.17-2.64; P=0.006), and use of proton-pump inhibitors (OR =1.67; CI =1.11-2.53; P=0.014). Transfer between hospital wards, preexisting dementia, previous delirium incidents, previous fall incidents, and use of proton-pump inhibitors are predictive of development of delirium in the geriatric inpatient setting.

Seasonal movements and Home-range use by female pronghorns in sagebrush-steppe communities of western South Dakota

USGS Publications Warehouse

Jacques, C.N.; Jenks, J.A.; Klaver, R.W.

2009-01-01

Knowledge of seasonal movements by pronghorns (Antilocapra americana) within the easternmost extension of sagebrush-steppe communities is limited. Current hypotheses regarding movement patterns suggest that pronghorns initiate seasonal movements in response to severe winter weather, snowfall patterns, spatial and temporal variation in forage abundance, and availability of water. From January 2002 to August 2005, we monitored movements of 76 adult (≥1.5 years) female pronghorns on 2 study areas (Harding and Fall River counties) in western South Dakota. We collected 8,750 visual locations, calculated 204 home ranges, and documented 17 seasonal movements. Eighty-four percent (n = 55) of pronghorns were nonmigratory and 10% (n = 6) were conditional migrators. Mean distance between summer and winter range was 23.1 km (SE = 2.8 km, n = 13). Five adult pronghorns (8%) dispersed a mean distance of 37.6 km (SE = 12.4 km); of which 1 female moved a straight-line distance of 75.0 km. Winter and summer home-range size varied (P < 0.0001) between study sites. Mean 95% adaptive kernel winter and summer home-range size of pronghorns was 55.5 and 19.7 km2, respectively, in Harding County and 127.2 and 65.9 km2, respectively, in Fall River County. Nonmigratory behavior exhibited by pronghorns was likely associated with minimal snow cover and moderate temperatures during winter 2002–2004. Variation in size of adult seasonal home ranges between sites was likely associated with differences in forage distribution and availability between regions.

The informativity of sound modulates crossmodal facilitation of visual discrimination: a fMRI study.

PubMed

Li, Qi; Yu, Hongtao; Li, Xiujun; Sun, Hongzan; Yang, Jingjing; Li, Chunlin

2017-01-18

Many studies have investigated behavioral crossmodal facilitation when a visual stimulus is accompanied by a concurrent task-irrelevant sound. Lippert and colleagues reported that a concurrent task-irrelevant sound reduced the uncertainty of the timing of the visual display and improved perceptional responses (informative sound). However, the neural mechanism by which the informativity of sound affected crossmodal facilitation of visual discrimination remained unclear. In this study, we used event-related functional MRI to investigate the neural mechanisms underlying the role of informativity of sound in crossmodal facilitation of visual discrimination. Significantly faster reaction times were observed when there was an informative relationship between auditory and visual stimuli. The functional MRI results showed sound informativity-induced activation enhancement including the left fusiform gyrus and the right lateral occipital complex. Further correlation analysis showed that the right lateral occipital complex was significantly correlated with the behavioral benefit in reaction times. This suggests that this region was modulated by the informative relationship within audiovisual stimuli that was learnt during the experiment, resulting in late-stage multisensory integration and enhanced behavioral responses.

Act quickly, decide later: long-latency visual processing underlies perceptual decisions but not reflexive behavior.

PubMed

Jolij, Jacob; Scholte, H Steven; van Gaal, Simon; Hodgson, Timothy L; Lamme, Victor A F

2011-12-01

Humans largely guide their behavior by their visual representation of the world. Recent studies have shown that visual information can trigger behavior within 150 msec, suggesting that visually guided responses to external events, in fact, precede conscious awareness of those events. However, is such a view correct? By using a texture discrimination task, we show that the brain relies on long-latency visual processing in order to guide perceptual decisions. Decreasing stimulus saliency leads to selective changes in long-latency visually evoked potential components reflecting scene segmentation. These latency changes are accompanied by almost equal changes in simple RTs and points of subjective simultaneity. Furthermore, we find a strong correlation between individual RTs and the latencies of scene segmentation related components in the visually evoked potentials, showing that the processes underlying these late brain potentials are critical in triggering a response. However, using the same texture stimuli in an antisaccade task, we found that reflexive, but erroneous, prosaccades, but not antisaccades, can be triggered by earlier visual processes. In other words: The brain can act quickly, but decides late. Differences between our study and earlier findings suggesting that action precedes conscious awareness can be explained by assuming that task demands determine whether a fast and unconscious, or a slower and conscious, representation is used to initiate a visually guided response.

A Behavioral Study of Distraction by Vibrotactile Novelty

ERIC Educational Resources Information Center

Parmentier, Fabrice B. R.; Ljungberg, Jessica K.; Elsley, Jane V.; Lindkvist, Markus

2011-01-01

Past research has demonstrated that the occurrence of unexpected task-irrelevant changes in the auditory or visual sensory channels captured attention in an obligatory fashion, hindering behavioral performance in ongoing auditory or visual categorization tasks and generating orientation and re-orientation electrophysiological responses. We report…

EnsembleGraph: Interactive Visual Analysis of Spatial-Temporal Behavior for Ensemble Simulation Data

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

Shu, Qingya; Guo, Hanqi; Che, Limei

We present a novel visualization framework—EnsembleGraph— for analyzing ensemble simulation data, in order to help scientists understand behavior similarities between ensemble members over space and time. A graph-based representation is used to visualize individual spatiotemporal regions with similar behaviors, which are extracted by hierarchical clustering algorithms. A user interface with multiple-linked views is provided, which enables users to explore, locate, and compare regions that have similar behaviors between and then users can investigate and analyze the selected regions in detail. The driving application of this paper is the studies on regional emission influences over tropospheric ozone, which is based onmore » ensemble simulations conducted with different anthropogenic emission absences using the MOZART-4 (model of ozone and related tracers, version 4) model. We demonstrate the effectiveness of our method by visualizing the MOZART-4 ensemble simulation data and evaluating the relative regional emission influences on tropospheric ozone concentrations. Positive feedbacks from domain experts and two case studies prove efficiency of our method.« less

Looking for ideas: Eye behavior during goal-directed internally focused cognition☆

PubMed Central

Walcher, Sonja; Körner, Christof; Benedek, Mathias

2017-01-01

Humans have a highly developed visual system, yet we spend a high proportion of our time awake ignoring the visual world and attending to our own thoughts. The present study examined eye movement characteristics of goal-directed internally focused cognition. Deliberate internally focused cognition was induced by an idea generation task. A letter-by-letter reading task served as external task. Idea generation (vs. reading) was associated with more and longer blinks and fewer microsaccades indicating an attenuation of visual input. Idea generation was further associated with more and shorter fixations, more saccades and saccades with higher amplitudes as well as heightened stimulus-independent variation of eye vergence. The latter results suggest a coupling of eye behavior to internally generated information and associated cognitive processes, i.e. searching for ideas. Our results support eye behavior patterns as indicators of goal-directed internally focused cognition through mechanisms of attenuation of visual input and coupling of eye behavior to internally generated information. PMID:28689088

Stiffness control of balance during dual task and prospective falls in older adults: the MOBILIZE Boston Study.

PubMed

Kang, Hyun Gu; Quach, Lien; Li, Wenjun; Lipsitz, Lewis A

2013-09-01

Outdoor fallers differ from indoor fallers substantially in demographics, lifestyle, health condition and physical function. Biomechanical predictors of outdoor falls have not been well characterized. Current validated measures of postural deficits, which describe only the overall postural behavior, are predictive of indoor falls but not outdoor falls. We hypothesized that a model-based description of postural muscle tone and reflexes, particularly during dual tasking, would predict outdoor falls. We tested whether postural stiffness and damping from an inverted pendulum model were predictive of future indoor and outdoor falls among older adults from the MOBILIZE Boston Study. The center of pressure data during standing were obtained from 717 participants aged 77.9±5.3 years. Participants stood barefoot with eyes open for 30s per trial, in two sets of five standing trials. One set included a serial subtractions task. Postural stiffness and damping values were determined from the postural sway data. After the postural measurements, falls were monitored prospectively using a monthly mail-in calendar over 6-36 months. Associations of postural measures with fall rates were determined using negative binomial regressions. After covariate adjustments, postural stiffness (p=0.02-0.05) and damping (p=0.007-0.1) were associated with lower outdoor falls risk, but not with indoor falls. Results were invariant by direction (anteroposterior versus mediolateral) or by condition (quiet standing versus dual task). Outdoor fall risk may be tied to postural control more so than indoor falls. Dual tasking is likely related to fall risk among older and sicker older adults, but not those relatively healthy. Copyright © 2013 Elsevier B.V. All rights reserved.

Stiffness Control of Balance during Dual Task and Prospective Falls in Older Adults: The MOBILIZE Boston Study

PubMed Central

Kang, Hyun Gu; Quach, Lien; Li, Wenjun; Lipsitz, Lewis A.

2013-01-01

Outdoor fallers differ from indoor fallers substantially in demographics, lifestyle, health condition and physical function. Biomechanical predictors of outdoor falls have not been well characterized. Current validated measures of postural deficits, which describe only the overall postural behavior, are predictive of indoor falls but not outdoor falls. We hypothesized that a model-based description of postural muscle tone and reflexes, particularly during dual tasking, would predict outdoor falls. We tested whether postural stiffness and damping from an inverted pendulum model were predictive of future indoor and outdoor falls among older adults from the MOBILIZE Boston Study. The center of pressure data during standing were obtained from 717 participants aged 77.9±5.3 years. Participants stood barefoot with eyes open for 30 seconds per trial, in two sets of five standing trials. One set included a serial subtractions task. Postural stiffness and damping values were determined from the postural sway data. After the postural measurements, falls were monitored prospectively using a monthly mail-in calendar over 6-36 months. Associations of postural measures with fall rates were determined using negative binomial regressions. After covariate adjustments, postural stiffness (p=0.02-0.05) and damping (p=0.007-0.1) were associated with lower outdoor falls risk, but not with indoor falls. Results were invariant by direction (anteroposterior versus mediolateral) or by condition (quiet standing versus dual task). Outdoor fall risk may be tied to postural control more so than indoor falls. Dual tasking is likely related to fall risk among older and sicker older adults, but not those relatively healthy. PMID:23623606

Individual housing-based socioeconomic status predicts risk of accidental falls among adults.

PubMed

Ryu, Euijung; Juhn, Young J; Wheeler, Philip H; Hathcock, Matthew A; Wi, Chung-Il; Olson, Janet E; Cerhan, James R; Takahashi, Paul Y

2017-07-01

Accidental falls are a major public health concern among people of all ages. Little is known about whether an individual-level housing-based socioeconomic status measure is associated with the risk of accidental falls. Among 12,286 Mayo Clinic Biobank participants residing in Olmsted County, Minnesota, subjects who experienced accidental falls between the biobank enrollment and September 2014 were identified using ICD-9 codes evaluated at emergency departments. HOUSES (HOUsing-based Index of SocioEconomic Status), a socioeconomic status measure based on individual housing features, was also calculated. Cox regression models were utilized to assess the association of the HOUSES (in quartiles) with accidental fall risk. Seven hundred eleven (5.8%) participants had at least one emergency room visit due to an accidental fall during the study period. Subjects with higher HOUSES were less likely to experience falls in a dose-response manner (hazard ratio: 0.58; 95% confidence interval: 0.44-0.76 for comparing the highest to the lowest quartile). In addition, the HOUSES was positively associated with better health behaviors, social support, and functional status. The HOUSES is inversely associated with accidental fall risk requiring emergency care in a dose-response manner. The HOUSES may capture falls-related risk factors through housing features and socioeconomic status-related psychosocial factors. Copyright © 2017 Elsevier Inc. All rights reserved.

International Earth Science Constellation Mission Operations Working Group: Constellation Coordination System (CCS) Status. [Constellation Coordination System (CCS) Status

NASA Technical Reports Server (NTRS)

Skeberdis, Daniel

2016-01-01

This is a presentation at the MOWG fall meeting that will discuss CCS purpose, future status, security enhancements, arbitrary ephemeris mission features, overview of CCS 7.3, approach for the use of NORAD TLEs, account and data security, CCS System virtualization, control box visualization modification and other enhancements.

Electrostatic Deformation of Liquid Surfaces by a Charged Rod and a Van De Graaff Generator

ERIC Educational Resources Information Center

Slisko, Josip; García-Molina, Rafael; Abril, Isabel

2014-01-01

Authors of physics textbooks frequently use the deflection of a thin, vertically falling water jet by a charged balloon, comb, or rod as a visually appealing and conceptually relevant example of electrostatic attraction. Nevertheless, no attempts are made to explore whether these charged bodies could cause visible deformation of a horizontal water…

Reading Improvement through Art Replicator Manual of Instruction, 3rd Edition

ERIC Educational Resources Information Center

Corwin, Sylvia K., Ed.

2013-01-01

Reading Improvement Through Art (RITA) program is an interdisciplinary approach to literacy that blends visual art with reading comprehension, evaluated in nine New York City urban high schools. 240 problem readers participating in the pilot program were pre- and post-tested in the Fall 1975 and Spring 1976 semesters. The testing showed the 9th…

Modulation of visual physiology by behavioral state in monkeys, mice, and flies.

PubMed

Maimon, Gaby

2011-08-01

When a monkey attends to a visual stimulus, neurons in visual cortex respond differently to that stimulus than when the monkey attends elsewhere. In the 25 years since the initial discovery, the study of attention in primates has been central to understanding flexible visual processing. Recent experiments demonstrate that visual neurons in mice and fruit flies are modulated by locomotor behaviors, like running and flying, in a manner that resembles attention-based modulations in primates. The similar findings across species argue for a more generalized view of state-dependent sensory processing and for a renewed dialogue among vertebrate and invertebrate research communities. Copyright © 2011 Elsevier Ltd. All rights reserved.

The dorsal "action" pathway.

PubMed

Gallivan, Jason P; Goodale, Melvyn A

2018-01-01

In 1992, Goodale and Milner proposed a division of labor in the visual pathways of the primate cerebral cortex. According to their account, the ventral pathway, which projects to occipitotemporal cortex, constructs our visual percepts, while the dorsal pathway, which projects to posterior parietal cortex, mediates the visual control of action. Although the framing of the two-visual-system hypothesis has not been without controversy, it is clear that vision for action and vision for perception have distinct computational requirements, and significant support for the proposed neuroanatomic division has continued to emerge over the last two decades from human neuropsychology, neuroimaging, behavioral psychophysics, and monkey neurophysiology. In this chapter, we review much of this evidence, with a particular focus on recent findings from human neuroimaging and monkey neurophysiology, demonstrating a specialized role for parietal cortex in visually guided behavior. But even though the available evidence suggests that dedicated circuits mediate action and perception, in order to produce adaptive goal-directed behavior there must be a close coupling and seamless integration of information processing across these two systems. We discuss such ventral-dorsal-stream interactions and argue that the two pathways play different, yet complementary, roles in the production of skilled behavior. Copyright © 2018 Elsevier B.V. All rights reserved.

An asymmetrical relationship between verbal and visual thinking: converging evidence from behavior and fMRI

PubMed Central

Amit, Elinor; Hoeflin, Caitlyn; Hamzah, Nada; Fedorenko, Evelina

2017-01-01

Humans rely on at least two modes of thought: verbal (inner speech) and visual (imagery). Are these modes independent, or does engaging in one entail engaging in the other? To address this question, we performed a behavioral and an fMRI study. In the behavioral experiment, participants received a prompt and were asked to either silently generate a sentence or create a visual image in their mind. They were then asked to judge the vividness of the resulting representation, and of the potentially accompanying representation in the other format. In the fMRI experiment, participants had to recall sentences or images (that they were familiarized with prior to the scanning session) given prompts, or read sentences and view images, in the control, perceptual, condition. An asymmetry was observed between inner speech and visual imagery. In particular, inner speech was engaged to a greater extent during verbal than visual thought, but visual imagery was engaged to a similar extent during both modes of thought. Thus, it appears that people generate more robust verbal representations during deliberate inner speech compared to when their intent is to visualize. However, they generate visual images regardless of whether their intent is to visualize or to think verbally. One possible interpretation of these results is that visual thinking is somehow primary, given the relatively late emergence of verbal abilities during human development and in the evolution of our species. PMID:28323162

An asymmetrical relationship between verbal and visual thinking: Converging evidence from behavior and fMRI.

PubMed

Amit, Elinor; Hoeflin, Caitlyn; Hamzah, Nada; Fedorenko, Evelina

2017-05-15

Humans rely on at least two modes of thought: verbal (inner speech) and visual (imagery). Are these modes independent, or does engaging in one entail engaging in the other? To address this question, we performed a behavioral and an fMRI study. In the behavioral experiment, participants received a prompt and were asked to either silently generate a sentence or create a visual image in their mind. They were then asked to judge the vividness of the resulting representation, and of the potentially accompanying representation in the other format. In the fMRI experiment, participants had to recall sentences or images (that they were familiarized with prior to the scanning session) given prompts, or read sentences and view images, in the control, perceptual, condition. An asymmetry was observed between inner speech and visual imagery. In particular, inner speech was engaged to a greater extent during verbal than visual thought, but visual imagery was engaged to a similar extent during both modes of thought. Thus, it appears that people generate more robust verbal representations during deliberate inner speech compared to when their intent is to visualize. However, they generate visual images regardless of whether their intent is to visualize or to think verbally. One possible interpretation of these results is that visual thinking is somehow primary, given the relatively late emergence of verbal abilities during human development and in the evolution of our species. Copyright © 2017 Elsevier Inc. All rights reserved.

Psychological evaluation of treated females with virilizing congenital adrenal hyperplasia.

PubMed

Hurtig, A L; Radhakrishnan, J; Reyes, H M; Rosenthal, I M

1983-12-01

The psychological development of females with congenital adrenal hyperplasia (CAH) has been previously studied by Money, et al, who found that psychological development of sex identity was consistent with sex assignment despite virilizing adrenal hormones and abnormal external genitalia requiring surgical correction. In this study, using a variety of psychological tests, we assessed the sex-dimorphic behavior, body image, cognitive functioning, and sex-role identity of nine patients ranging in age from 13 to 21, all treated with glucocorticoids and surgical correction. Four of the nine showed moderate virilization despite treatment. Psychological measures included the Wechsler Intelligence Scale for Children-Revised (WISC-R), the Bem Sex-Role Inventory, the Draw-A-Person (DAP) and an interview with patient and family. Results indicate that patients fall within the normal expectable range for this developmental period in visual-spatial and verbal cognitive functioning, in sex-role identity, and in social interpersonal early behaviors. In two areas of functioning these patients demonstrated some variance from the norms, specifically in sexual identity and early activity levels. This suggests that sexual identity and physical activity are most prone to hormonal and psychological impact but that cognition and sex-role identity are not affected. Future studies of this sample will look at personality dimensions such as ego functioning, defense and affect to consider the impact of body image concerns and conflicts.

Evolution and ecology of directed aerial descent in arboreal ants.

PubMed

Yanoviak, Stephen P; Munk, Yonatan; Dudley, Robert

2011-12-01

Directed aerial descent (DAD) is used by a variety of arboreal animals to escape predators, to remain in the canopy, and to access resources. Here, we build upon the discovery of DAD in ants of tropical canopies by summarizing its known phylogenetic distribution among ant genera, and within both the subfamily Pseudomyrmecinae and the genus Cephalotes. DAD has multiple evolutionary origins in ants, occurring independently in numerous genera in the subfamilies Myrmicinae, Formicinae, and Pseudomyrmecinae. Ablation experiments and video recordings of ants in a vertical wind tunnel showed that DAD in Cephalotes atratus is achieved via postural changes, specifically orientation of the legs and gaster. The occurrence of DAD in Formicinae indicates that the presence of a postpetiole is not essential for the behavior. Evidence to date indicates that gliding behavior is accomplished by visual targeting mediated by the compound eyes, and is restricted to diurnally active ants that nest in trees. Occlusion of ocelli in Pseudomyrmex gracilis workers had no effect on their success or performance in gliding. Experimental assessment of the fate of ants that fall to the understory showed that ants landing in water are 15 times more likely to suffer lethal attacks than are ants landing in leaf litter. Variation in both the aerodynamic mechanisms and selective advantages of DAD merits further study given the broad taxonomic diversity of arboreal ants that engage in this intriguing form of flight.

Searching for the right word: Hybrid visual and memory search for words

PubMed Central

Boettcher, Sage E. P.; Wolfe, Jeremy M.

2016-01-01

In “Hybrid Search” (Wolfe 2012) observers search through visual space for any of multiple targets held in memory. With photorealistic objects as stimuli, response times (RTs) increase linearly with the visual set size and logarithmically with memory set size even when over 100 items are committed to memory. It is well established that pictures of objects are particularly easy to memorize (Brady, Konkle, Alvarez, & Olivia, 2008). Would hybrid search performance be similar if the targets were words or phrases where word order can be important and where the processes of memorization might be different? In Experiment One, observers memorized 2, 4, 8, or 16 words in 4 different blocks. After passing a memory test, confirming memorization of the list, observers searched for these words in visual displays containing 2 to 16 words. Replicating Wolfe (2012), RTs increased linearly with the visual set size and logarithmically with the length of the word list. The word lists of Experiment One were random. In Experiment Two, words were drawn from phrases that observers reported knowing by heart (E.G. “London Bridge is falling down”). Observers were asked to provide four phrases ranging in length from 2 words to a phrase of no less than 20 words (range 21–86). Words longer than 2 characters from the phrase constituted the target list. Distractor words were matched for length and frequency. Even with these strongly ordered lists, results again replicated the curvilinear function of memory set size seen in hybrid search. One might expect serial position effects; perhaps reducing RTs for the first (primacy) and/or last (recency) members of a list (Atkinson & Shiffrin 1968; Murdock, 1962). Surprisingly we showed no reliable effects of word order. Thus, in “London Bridge is falling down”, “London” and “down” are found no faster than “falling”. PMID:25788035

Functionally defined white matter reveals segregated pathways in human ventral temporal cortex associated with category-specific processing

PubMed Central

Gomez, Jesse; Pestilli, Franco; Witthoft, Nathan; Golarai, Golijeh; Liberman, Alina; Poltoratski, Sonia; Yoon, Jennifer; Grill-Spector, Kalanit

2014-01-01

Summary It is unknown if the white matter properties associated with specific visual networks selectively affect category-specific processing. In a novel protocol we combined measurements of white matter structure, functional selectivity, and behavior in the same subjects. We find two parallel white matter pathways along the ventral temporal lobe connecting to either face-selective or place-selective regions. Diffusion properties of portions of these tracts adjacent to face- and place-selective regions of ventral temporal cortex correlate with behavioral performance for face or place processing, respectively. Strikingly, adults with developmental prosopagnosia (face blindness) express an atypical structure-behavior relationship near face-selective cortex, suggesting that white matter atypicalities in this region may have behavioral consequences. These data suggest that examining the interplay between cortical function, anatomical connectivity, and visual behavior is integral to understanding functional networks and their role in producing visual abilities and deficits. PMID:25569351

A Neurobehavioral Model of Flexible Spatial Language Behaviors

PubMed Central

Lipinski, John; Schneegans, Sebastian; Sandamirskaya, Yulia; Spencer, John P.; Schöner, Gregor

2012-01-01

We propose a neural dynamic model that specifies how low-level visual processes can be integrated with higher level cognition to achieve flexible spatial language behaviors. This model uses real-word visual input that is linked to relational spatial descriptions through a neural mechanism for reference frame transformations. We demonstrate that the system can extract spatial relations from visual scenes, select items based on relational spatial descriptions, and perform reference object selection in a single unified architecture. We further show that the performance of the system is consistent with behavioral data in humans by simulating results from 2 independent empirical studies, 1 spatial term rating task and 1 study of reference object selection behavior. The architecture we present thereby achieves a high degree of task flexibility under realistic stimulus conditions. At the same time, it also provides a detailed neural grounding for complex behavioral and cognitive processes. PMID:21517224

[Social behavior, musicality and visual perception in monogloid children (author's transl)].

PubMed

Rabensteiner, B

1975-01-01

Forty-nine mongoloid and 48 non-mongol test persons of equivalent age and intelligence were selected and studied with respect to social behavior, speech disorders (observation of behavior), musicality and visual perception. There were significant differences in favor of the mongols with respect to social adaption. Speech disorders of all kinds occurred significantly more frequently in mongol children; stuttering was significantly more frequent in the boys. The mongol group did significantly better in the musicality test; the difference in the rhythmical part was highly significant. The average differences in the capacity for visual discrimination of colors, geometrical forms and the spatial relationship of geometrical forms were not significant.

Visual Working Memory Load-Related Changes in Neural Activity and Functional Connectivity

PubMed Central

Li, Ling; Zhang, Jin-Xiang; Jiang, Tao

2011-01-01

Background Visual working memory (VWM) helps us store visual information to prepare for subsequent behavior. The neuronal mechanisms for sustaining coherent visual information and the mechanisms for limited VWM capacity have remained uncharacterized. Although numerous studies have utilized behavioral accuracy, neural activity, and connectivity to explore the mechanism of VWM retention, little is known about the load-related changes in functional connectivity for hemi-field VWM retention. Methodology/Principal Findings In this study, we recorded electroencephalography (EEG) from 14 normal young adults while they performed a bilateral visual field memory task. Subjects had more rapid and accurate responses to the left visual field (LVF) memory condition. The difference in mean amplitude between the ipsilateral and contralateral event-related potential (ERP) at parietal-occipital electrodes in retention interval period was obtained with six different memory loads. Functional connectivity between 128 scalp regions was measured by EEG phase synchronization in the theta- (4–8 Hz), alpha- (8–12 Hz), beta- (12–32 Hz), and gamma- (32–40 Hz) frequency bands. The resulting matrices were converted to graphs, and mean degree, clustering coefficient and shortest path length was computed as a function of memory load. The results showed that brain networks of theta-, alpha-, beta-, and gamma- frequency bands were load-dependent and visual-field dependent. The networks of theta- and alpha- bands phase synchrony were most predominant in retention period for right visual field (RVF) WM than for LVF WM. Furthermore, only for RVF memory condition, brain network density of theta-band during the retention interval were linked to the delay of behavior reaction time, and the topological property of alpha-band network was negative correlation with behavior accuracy. Conclusions/Significance We suggest that the differences in theta- and alpha- bands between LVF and RVF conditions in functional connectivity and topological properties during retention period may result in the decline of behavioral performance in RVF task. PMID:21789253

Evolutionary relevance facilitates visual information processing.

PubMed

Jackson, Russell E; Calvillo, Dusti P

2013-11-03

Visual search of the environment is a fundamental human behavior that perceptual load affects powerfully. Previously investigated means for overcoming the inhibitions of high perceptual load, however, generalize poorly to real-world human behavior. We hypothesized that humans would process evolutionarily relevant stimuli more efficiently than evolutionarily novel stimuli, and evolutionary relevance would mitigate the repercussions of high perceptual load during visual search. Animacy is a significant component to evolutionary relevance of visual stimuli because perceiving animate entities is time-sensitive in ways that pose significant evolutionary consequences. Participants completing a visual search task located evolutionarily relevant and animate objects fastest and with the least impact of high perceptual load. Evolutionarily novel and inanimate objects were located slowest and with the highest impact of perceptual load. Evolutionary relevance may importantly affect everyday visual information processing.

Development of a Theory-Based Intervention to Increase Clinical Measurement of Reactive Balance in Adults at Risk of Falls.

PubMed

Sibley, Kathryn M; Brooks, Dina; Gardner, Paula; Janaudis-Ferreira, Tania; McGlynn, Mandy; OʼHoski, Sachi; McEwen, Sara; Salbach, Nancy M; Shaffer, Jennifer; Shing, Paula; Straus, Sharon E; Jaglal, Susan B

2016-04-01

Effective balance reactions are essential for avoiding falls, but are not regularly measured by physical therapists. Physical therapists report wanting to improve reactive balance assessment, and theory-based approaches are recommended as the foundation for the development of interventions. This article describes how a behavior change theory for health care providers, the theoretical domains framework (TDF), was used to develop an intervention to increase reactive balance measurement among physical therapists who work in rehabilitation settings and treat adults who are at risk of falls. We employed published recommendations for using the TDF-guided intervention development. We identified what health care provider behavior is in need of change, relevant barriers and facilitators, strategies to address them, and how we would measure behavior change. In this case, identifying strategies required selecting both a reactive balance measure and behavior change techniques. Previous research had determined that physical therapists need to increase reactive balance measurement, and identified barriers and facilitators that corresponded to 8 TDF domains. A published review informed the selection of the Balance Evaluation Systems Test (Reactive Postural Responses Section) as addressing the barriers and facilitators, and existing research informed the selection of 9 established behavior change techniques corresponding to each identified TDF domain. The TDF framework were incorporated into a 12-month intervention with interactive group sessions, local champions, and health record modifications. Intervention effect can be evaluated using health record abstraction, questionnaires, and qualitative semistructured interviews. Although future research will evaluate the intervention in a controlled study, the process of theory-based intervention development can be applied to other rehabilitation research contexts, maximizing the impact of this work.Video Abstract is available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A123).

Visualization of oil behavior in a small 4-cycle engine with electrical motoring by neutron radiography

NASA Astrophysics Data System (ADS)

Nakamura, M.; Sugimoto, K.; Asano, H.; Murakawa, H.; Takenaka, N.; Mochiki, K.

2009-06-01

Neutron radiography is suitable for the visualization of liquid behavior in a metallic machine. Observation of oil behavior in a small 4-cycle engine on operating was carried out by using the neutron radiography facility at JRR-3 in JAEA. The engine was not fired but operated by an electrical motor. Movies were taken by a neutron image intensifier with a color CCD camera of 8-bit resolution, 30 frames/s and 640×480 pixels developed by Toshiba Corp. The engine was placed on a turn table and was rotated, so the movie could be taken from any angle. Numbers of revolution of the engine were changed from 260 to 1200 rpm. Visualized images of the mechanism and the oil behavior in the engine were obtained.

Visual Persons Behavior Diary Generation Model based on Trajectories and Pose Estimation

NASA Astrophysics Data System (ADS)

Gang, Chen; Bin, Chen; Yuming, Liu; Hui, Li

2018-03-01

The behavior pattern of persons was the important output of the surveillance analysis. This paper focus on the generation model of visual person behavior diary. The pipeline includes the person detection, tracking, and the person behavior classify. This paper adopts the deep convolutional neural model YOLO (You Only Look Once)V2 for person detection module. Multi person tracking was based on the detection framework. The Hungarian assignment algorithm was used to the matching. The person appearance model was integrated by HSV color model and Hash code model. The person object motion was estimated by the Kalman Filter. The multi objects were matching with exist tracklets through the appearance and motion location distance by the Hungarian assignment method. A long continuous trajectory for one person was get by the spatial-temporal continual linking algorithm. And the face recognition information was used to identify the trajectory. The trajectories with identification information can be used to generate the visual diary of person behavior based on the scene context information and person action estimation. The relevant modules are tested in public data sets and our own capture video sets. The test results show that the method can be used to generate the visual person behavior pattern diary with certain accuracy.

Reliability-Weighted Integration of Audiovisual Signals Can Be Modulated by Top-down Attention

PubMed Central

Noppeney, Uta

2018-01-01

Abstract Behaviorally, it is well established that human observers integrate signals near-optimally weighted in proportion to their reliabilities as predicted by maximum likelihood estimation. Yet, despite abundant behavioral evidence, it is unclear how the human brain accomplishes this feat. In a spatial ventriloquist paradigm, participants were presented with auditory, visual, and audiovisual signals and reported the location of the auditory or the visual signal. Combining psychophysics, multivariate functional MRI (fMRI) decoding, and models of maximum likelihood estimation (MLE), we characterized the computational operations underlying audiovisual integration at distinct cortical levels. We estimated observers’ behavioral weights by fitting psychometric functions to participants’ localization responses. Likewise, we estimated the neural weights by fitting neurometric functions to spatial locations decoded from regional fMRI activation patterns. Our results demonstrate that low-level auditory and visual areas encode predominantly the spatial location of the signal component of a region’s preferred auditory (or visual) modality. By contrast, intraparietal sulcus forms spatial representations by integrating auditory and visual signals weighted by their reliabilities. Critically, the neural and behavioral weights and the variance of the spatial representations depended not only on the sensory reliabilities as predicted by the MLE model but also on participants’ modality-specific attention and report (i.e., visual vs. auditory). These results suggest that audiovisual integration is not exclusively determined by bottom-up sensory reliabilities. Instead, modality-specific attention and report can flexibly modulate how intraparietal sulcus integrates sensory signals into spatial representations to guide behavioral responses (e.g., localization and orienting). PMID:29527567

Knowledge, behavioral practices, and experiences of outdoor fallers: Implications for prevention programs.

PubMed

Chippendale, Tracy; Raveis, Victoria

2017-09-01

Although the epidemiology and prevention of falls has been well studied, the focus has been on indoor rather than outdoor falls. Older adults' knowledge of outdoor risk factors and their outdoor fall prevention practices have not been examined. To fill this gap, and to inform the development of a prevention program, we sought to explore the experiences and fall prevention knowledge and practices of older adults who had sustained an outdoor fall. A cross-sectional study using random digit telephone dialing was used to survey community dwelling seniors (N=120) across the five boroughs of New York City. We used the Outdoor Falls Questionnaire (OFQ), a valid and reliable tool as the survey instrument. Perceived outdoor fall risks, strategies used for prevention, and outdoor fall experiences were examined. SPSS version 21 was used for descriptive analysis of participant characteristics and to determine frequencies of perceived outdoor fall risks and strategies used for prevention. Phenomenological analysis was used with the qualitative data. Qualitative and quantitative data were analyzed separately and a mixed methods matrix was used to interpret and integrate the findings. Analysis revealed diverse unmet education and training needs including the importance of using single vision glasses, understanding the fall risks associated with recreational areas and parking lots, safe outdoor walking strategies, safe carrying of items on level and uneven surfaces, as well as when walking up and down stairs, and safety in opening/closing doors. Study findings are informative for outdoor fall prevention programs as well as practice. Copyright © 2017 Elsevier B.V. All rights reserved.

Visual recognition and visually guided action after early bilateral lesion of occipital cortex: a behavioral study of a 4.6-year-old girl.

PubMed

Amicuzi, Ileana; Stortini, Massimo; Petrarca, Maurizio; Di Giulio, Paola; Di Rosa, Giuseppe; Fariello, Giuseppe; Longo, Daniela; Cannatà, Vittorio; Genovese, Elisabetta; Castelli, Enrico

2006-10-01

We report the case of a 4.6-year-old girl born pre-term with early bilateral occipital damage. It was revealed that the child had non-severely impaired basic visual abilities and ocular motility, a selective perceptual deficit of figure-ground segregation, impaired visual recognition and abnormal navigating through space. Even if the child's visual functioning was not optimal, this was the expression of adaptive anatomic and functional brain modifications that occurred following the early lesion. Anatomic brain structure was studied with anatomic MRI and Diffusor Tensor Imaging (DTI)-MRI. This behavioral study may provide an important contribution to understanding the impact of an early lesion of the visual system on the development of visual functions and on the immature brain's potential for reorganisation related to when the damage occurred.

Visualization techniques for malware behavior analysis

NASA Astrophysics Data System (ADS)

Grégio, André R. A.; Santos, Rafael D. C.

2011-06-01

Malware spread via Internet is a great security threat, so studying their behavior is important to identify and classify them. Using SSDT hooking we can obtain malware behavior by running it in a controlled environment and capturing interactions with the target operating system regarding file, process, registry, network and mutex activities. This generates a chain of events that can be used to compare them with other known malware. In this paper we present a simple approach to convert malware behavior into activity graphs and show some visualization techniques that can be used to analyze malware behavior, individually or grouped.

Heat transfer in GTA welding arcs

NASA Astrophysics Data System (ADS)

Huft, Nathan J.

Heat transfer characteristics of Gas Tungsten Arc Welding (GTAW) arcs with arc currents of 50 to 125 A and arc lengths of 3 to 11 mm were measured experimentally through wet calorimetry. The data collected were used to calculate how much heat reported to the cathode and anode and how much was lost from the arc column. A Visual Basic for Applications (VBA) macro was written to further analyze the data and account for Joule heating within the electrodes and radiation and convection losses from the arc, providing a detailed account of how heat was generated and dissipated within the system. These values were then used to calculate arc efficiencies, arc column voltages, and anode and cathode fall voltages. Trends were noted for variances in the arc column voltage, power dissipated from the arc column, and the total power dissipated by the system with changing arc length. Trends for variances in the anode and cathode fall voltages, total power dissipated, Joule heating within the torches and electrodes with changing arc current were also noted. In addition, the power distribution between the anode and cathode for each combination of arc length and arc current was examined. Keywords: Gas Tungsten Arc Welding, GTAW, anode fall, cathode fall, heat transfer, wet calorimetry

Disruption of visual awareness during the attentional blink is reflected by selective disruption of late-stage neural processing

PubMed Central

Harris, Joseph A.; McMahon, Alex R.; Woldorff, Marty G.

2015-01-01

Any information represented in the brain holds the potential to influence behavior. It is therefore of broad interest to determine the extent and quality of neural processing of stimulus input that occurs with and without awareness. The attentional blink is a useful tool for dissociating neural and behavioral measures of perceptual visual processing across conditions of awareness. The extent of higher-order visual information beyond basic sensory signaling that is processed during the attentional blink remains controversial. To determine what neural processing at the level of visual-object identification occurs in the absence of awareness, electrophysiological responses to images of faces and houses were recorded both within and outside of the attentional blink period during a rapid serial visual presentation (RSVP) stream. Electrophysiological results were sorted according to behavioral performance (correctly identified targets versus missed targets) within these blink and non-blink periods. An early index of face-specific processing (the N170, 140–220 ms post-stimulus) was observed regardless of whether the subject demonstrated awareness of the stimulus, whereas a later face-specific effect with the same topographic distribution (500–700 ms post-stimulus) was only seen for accurate behavioral discrimination of the stimulus content. The present findings suggest a multi-stage process of object-category processing, with only the later phase being associated with explicit visual awareness. PMID:23859644

Situated sentence processing: the coordinated interplay account and a neurobehavioral model.

PubMed

Crocker, Matthew W; Knoeferle, Pia; Mayberry, Marshall R

2010-03-01

Empirical evidence demonstrating that sentence meaning is rapidly reconciled with the visual environment has been broadly construed as supporting the seamless interaction of visual and linguistic representations during situated comprehension. Based on recent behavioral and neuroscientific findings, however, we argue for the more deeply rooted coordination of the mechanisms underlying visual and linguistic processing, and for jointly considering the behavioral and neural correlates of scene-sentence reconciliation during situated comprehension. The Coordinated Interplay Account (CIA; Knoeferle, P., & Crocker, M. W. (2007). The influence of recent scene events on spoken comprehension: Evidence from eye movements. Journal of Memory and Language, 57(4), 519-543) asserts that incremental linguistic interpretation actively directs attention in the visual environment, thereby increasing the salience of attended scene information for comprehension. We review behavioral and neuroscientific findings in support of the CIA's three processing stages: (i) incremental sentence interpretation, (ii) language-mediated visual attention, and (iii) the on-line influence of non-linguistic visual context. We then describe a recently developed connectionist model which both embodies the central CIA proposals and has been successfully applied in modeling a range of behavioral findings from the visual world paradigm (Mayberry, M. R., Crocker, M. W., & Knoeferle, P. (2009). Learning to attend: A connectionist model of situated language comprehension. Cognitive Science). Results from a new simulation suggest the model also correlates with event-related brain potentials elicited by the immediate use of visual context for linguistic disambiguation (Knoeferle, P., Habets, B., Crocker, M. W., & Münte, T. F. (2008). Visual scenes trigger immediate syntactic reanalysis: Evidence from ERPs during situated spoken comprehension. Cerebral Cortex, 18(4), 789-795). Finally, we argue that the mechanisms underlying interpretation, visual attention, and scene apprehension are not only in close temporal synchronization, but have co-adapted to optimize real-time visual grounding of situated spoken language, thus facilitating the association of linguistic, visual and motor representations that emerge during the course of our embodied linguistic experience in the world. Copyright 2009 Elsevier Inc. All rights reserved.

A Model of Anode Sheath Potential Evolution in a Transverse Magnetic Field

NASA Astrophysics Data System (ADS)

Foster, John E.; Gallimore, Alec D.

1996-11-01

It has been conjectured that the growth in the magnitude of the anode fall voltage with changing transverse magnetic field is a function of the ratio of available transverse current to the discharge current. It has been postulated that at small values of this ratio, the anode fall voltage and thus the near-anode electric field increases in order to assure that the prescribed discharge is maintained.footnote H. Hugel, IEEE Tran. Plas. Sci., PS-8,4, 1980 In this present work, a model is presented which predicts the behavior of the anode fall voltage as a function of transverse magnetic field. The model attempts to explain why the anode fall voltage depends so strongly on this ratio. In addition, it is further shown that because of the current ratio's strong dependence on local electron number density, ultimately it is the changes in near-anode ionization processes with varying transverse magnetic field that control the anode fall voltage.

Effects of Spatio-Temporal Aliasing on Pilot Performance in Active Control Tasks

NASA Technical Reports Server (NTRS)

Zaal, Peter; Sweet, Barbara

2010-01-01

Spatio-temporal aliasing affects pilot performance and control behavior. For increasing refresh rates: 1) Significant change in control behavior: a) Increase in visual gain and neuromuscular frequency. b) Decrease in visual time delay. 2) Increase in tracking performance: a) Decrease in RMSe. b) Increase in crossover frequency.