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Twenty five patients with right cerebral hemisphere damage and neglect participated in a series of bisection experiments. As expected, long lines were bisected to the right of true midpoint. By contrast, large circles and long white paper strips were bisected accurately, or with leftward errors. Small objects were less sensitive to stimulus properties: short lines and paper strips, and small circles, were bisected to the left of true midpoint, and these leftward errors were equally common as rightward errors with long lines. When asked to draw a perpendicular line of the same length as the presented horizontal line, patients overestimated the length of short lines but underestimated that of long lines. Presenting lines in near and far extrapersonal space selectively affected bisection of short lines. The results suggest that two opposing, independent mechanisms determine bisection performance in left neglect. [ABSTRACT FROM AUTHOR]

Objective: This paper examines drivers' allocation of attention using response time to a tactile detection response task (TDRT) while interacting with an in-vehicle information system (IVIS) over time.Background: Longer TDRT response time is associated with higher cognitive workload. However, it is not clear what role is assumed by the human and system in response to varying in-vehicle environments over time.Method: A driving simulator study with 24 participants was conducted with a restaurant selection task of two difficulty levels (easy and hard) presented in three modalities (audio only, visual only, hybrid). A linear mixed-effects model was applied to identify factors that affect TDRT response time. A nonparametric time-series model was also used to explore the visual attention allocation under the hybrid mode over time.Results: The visual-only mode significantly increased participants' response time compared with the audio-only mode. Females took longer to respond to the TDRT when engaged with an IVIS. The study showed that participants tend to use the visual component more toward the end of the easy tasks, whereas the visual mode was used more at the beginning of the harder tasks.Conclusion: The visual-only mode of the IVIS increased drivers' cognitive workload when compared with the auditory-only mode. Drivers showed different visual attention allocation during the easy and hard restaurant selection tasks in the hybrid mode.Application: The findings can help guide the design of automotive user interfaces and help manage cognitive workload. [ABSTRACT FROM AUTHOR]

Traditional cognitive assessment in neurological conditions involving physical disability is often prevented by the presence of verbal-motor impairment; to date, an extensive motor-verbal-free neuropsychological battery is not available for such purposes. We adapted a set of neuropsychological tests, assessing language, attentional abilities, executive functions and social cognition, for eye-tracking (ET) control, and explored its feasibility in a sample of healthy participants. Thirty healthy subjects performed a neuropsychological assessment, using an ET-based neuropsychological battery, together with standard "paper and pencil" cognitive measures for frontal (Frontal Assessment Battery-FAB) and working memory abilities (Digit Sequencing Task) and for global cognitive efficiency (Montreal Cognitive Assessment-MoCA). Psychological measures of anxiety (State-Trait Anxiety Inventory-Y-STAI-Y) and depression (Beck Depression Inventory-BDI) were also collected, and a usability questionnaire was administered. Significant correlations were observed between the "paper and pencil" screening of working memory abilities and the ET-based neuropsychological measures. The ET-based battery also correlated with the MoCA, while poor correlations were observed with the FAB. Usability aspects were found to be influenced by both working memory abilities and psychological components. The ET-based neuropsychological battery developed could provide an extensive assessment of cognitive functions, allowing participants to perform tasks independently from the integrity of motor or verbal channels. Further studies will be aimed at investigating validity and usability components in neurological populations with motor-verbal impairments. [ABSTRACT FROM AUTHOR]

This study compared administration of performance tests and visual analogue scales (VAS) using a newly developed pen computer (PenC) battery with established tests using either pencil-and-paper (PP) or conventional computer. The performance of 47 subjects (23 male, age 18-45 years, weight 51-112 kg) was compared on the two systems after a dose of ethanol (0.8 g/kg up to a maximum of 60 g for males, 50 g for females) or placebo in a double-blind two-period randomized crossover study. Mean (SD) blood ethanol concentrations (breathalyser) were 94.5 mg/100 ml (21.9) at the start of the test battery (30 min post-drink) and 80.2 (13.0) at the end of the battery (75 min post-drink). Ethanol effects were found in all tests, with most outcome measures showing significant slowing or loss of accuracy. Results from the Rapid Visual Information Processing, Sentence Verification and Continuous Attention tasks show that the ethanol-placebo difference and the statistical significance of this difference are in close correspondence for the two modes of administration. The pen computer versions of these tasks may therefore be used as direct replacements for the previous versions. Digit-Symbol and maze tasks did not correspond so closely both showing differences in the speed-accuracy trade-off between the two modes. These tests, however, are sensitive to the effects of ethanol, and may be useful in their own right. Principal component analysis suggested that VAS may be grouped into two factors: (1) 'functional integrity', including measures of alertness and perceived proficiency, and (2) 'mood', including happiness and sociability. Factor 1 showed substantial effects of ethanol, while factor 2 was unchanged. There was close agreement between the results from PP and PenC for both factors as well as for the Sober-Drunk scale, which showed the expected effects of ethanol. Thus pen computer VAS perform in a similar way to the PP versions. [ABSTRACT FROM AUTHOR]

Emotional deficits have been repetitively reported in Alzheimer's disease (AD) without clearly identifying how emotional processing is impaired in this pathology. This paper describes an investigation of early emotional processing, as measured by the effects of emotional visual stimuli on a saccadic task involving both pro (PS) and anti (AS) saccades. Sixteen patients with AD and 25 age-matched healthy controls were eye-tracked while they had to quickly move their gaze toward a positive, negative, or neutral image presented on a computer screen (in the PS condition) or away from the image (in the AS condition). The age-matched controls made more AS mistakes for negative stimuli than for other stimuli, and triggered PSs toward negative stimuli more quickly than toward other stimuli. In contrast, patients with AD showed no difference with regard to the emotional category in any of the tasks. The present study is the first to highlight a lack of early emotional attention in patients with AD. These results should be taken into account in the care provided to patients with AD, since this early impairment might seriously degrade their overall emotional functioning. [ABSTRACT FROM AUTHOR]

We assessed the influence of dimenhydrinate, cinnarizine and transdermal scopolamine on the ability to perform simulated naval crew tasks. The effect of single doses of dimenhydrinate, 100 mg, cinnarizine, 50 mg, and one transdermal scopolamine patch on psychomotor performance was evaluated using a double-blind, placebo-controlled, randomized, crossover design in three separate studies. A total of 60 young naval crew (20 for dimenhydrinate, 15 for cinnarizine and 25 for transdermal scopolamine) underwent a battery of computerized and paper and pencil performance tests, and filled out a questionnaire on side-effects and well-being self-assessment. Dimenhydrinate significantly impaired decision reaction time and auditory digit span. Most of the subjects who took dimenhydrinate also reported a subjective decrease in well-being and general performance abilities. Cinnarizine and transdermal scopolamine did not affect performance abilities. Cinnarizine was free of significant side-effects. Dry mouth was the only significant side-effect of transdermal scopolamine. These findings could be explained by the well-known sedative properties of dimenhydrinate and not by a specific effect on any particular cognitive or motor function. Our results suggest that dimenhydrinate, 100 mg, adversely affects psychomotor function, whereas single doses of cinnarizine, 50 mg, and transdermal scopolamine appear to be free of side-effects on performance and seem to be a preferable anti-seasickness drug for use by a naval crew. [ABSTRACT FROM AUTHOR]

Background: Distractions during surgical procedures have been linked to medical error and team inefficiency. This systematic review identifies the most common and most significant forms of distraction in order to devise guidelines for mitigating the effects of distractions in the OR.Methods: In January 2015, a PubMed and Google Scholar search yielded 963 articles, of which 17 (2 %) either directly observed the occurrence of distractions in operating rooms or conducted a laboratory experiment to determine the effect of distraction on surgical performance.Results: Observational studies indicated that movement and case-irrelevant conversation were the most frequently occurring distractions, but equipment and procedural distractions were the most severe. Laboratory studies indicated that (1) auditory and mental distractions can significantly impact surgical performance, but visual distractions do not incur the same level of effects; (2) task difficulty has an interaction effect with distractions; and (3) inexperienced subjects reduce their speed when faced with distractions, while experienced subjects did not.Conclusion: This systematic review suggests that operating room protocols should ensure that distractions from intermittent auditory and mental distractions are significantly reduced. In addition, surgical residents would benefit from training for intermittent auditory and mental distractions in order to develop automaticity and high skill performance during distractions, particularly during more difficult surgical tasks. It is unclear as to whether training should be done in the presence of distractions or distractions should only be used for post-training testing of levels of automaticity. [ABSTRACT FROM AUTHOR]

This paper reports evidence from a longitudinal study in which children's attention to shape in a laboratory task of artificial noun learning was correlated with a rate shift in noun acquisitions. Eight children were tested in the laboratory at 3-week intervals beginning when they had less than 25 nouns in their productive vocabulary (M age=17 months). Children were presented with a novel word generalization task at each session. Additionally, the study examined the kinds of words the children learned early, based on parent reports, and the statistical regularities inherent in those vocabularies. The results indicate that as children learned nouns, they also learned to attend to shape in the novel word task. At the same time, children showed an acceleration in new noun production outside of the laboratory. [ABSTRACT FROM AUTHOR]

A wealth of research is available examining children's story comprehension. However, little attention has been directed toward understanding the story comprehension of children with attention deficit hyperactivity disorder (ADHD). The present paper attempts to integrate the developmental literature on children's story comprehension with the little that is known about the story comprehension processes of children with ADHD. This review is guided by a network model of story representation that emphasizes the structure of causal and enabling relations between story events. Examination of the available studies indicates that children with ADHD lag behind their peers in their understanding of causal relations, and that their attentional problems may contribute to difficulties in understanding factual information in the preschool years and causally related information in the elementary years. Some evidence also is presented suggesting that children with ADHD are less effective in taking advantage of story structure features in guiding their recall of story events. Suggestions for future research are offered that would elaborate our knowledge of the developmental progression in the processing of complex information by children with ADHD. [ABSTRACT FROM AUTHOR]

This paper reports on a comparison of the two alternative tests of attention in the Mini-Mental State Examination (MMSE), a well-known cognitive screening tool. The two tests, serial subtraction by seven and backwards spelling of the word world, are often used interchangeably. In a large population-based sample, the two tests were found to be weakly associated with each other, with the former test appearing more difficult, although both were strongly associated with educational level. The authors discuss the implications of this finding in clinical and research settings, and make recom mendations for more consistent use of the instrument. (J Geriatr Psychiatry Neurol 1990;3:203-207). [ABSTRACT FROM PUBLISHER]

Background: Virtual Reality (VR) based methods for stroke rehabilitation have mainly focused on motor rehabilitation, but there is increasing interest in integrating motor and cognitive training to increase similarity to real-world settings. Unfortunately, more research is needed for the definition of which type of content should be used in the design of these tools. One possibility is the use of emotional stimuli, which are known to enhance attentional processes. According to the Socioemotional Selectivity Theory, as people age, the emotional salience arises for positive and neutral, but not for negative stimuli.Methods: For this study we developed a cognitive-motor VR task involving attention and short-term memory, and we investigated the impact of using emotional images of varying valence. The task consisted of finding a target image, shown for only two seconds, among fourteen neutral distractors, and selecting it through arm movements. After performing the VR task, a recall task took place and the patients had to identify the target images among a valence-matched number of distractors. Ten stroke patients participated in a within-subjects experiment with three conditions based on the valence of the images: positive, negative and neutral. Eye movements were recorded during VR task performance with an eye tracking system.Results: Our results show decreased attention for negative stimuli in the VR task performance when compared to neutral stimuli. The recall task shows significantly more wrongly identified images (false memories) for negative stimuli than for neutral. Regression and correlation analyses with the Montreal Cognitive Assessment and the Geriatric Depression Scale revealed differential effects of cognitive function and depressive symptomatology in the encoding and recall of positive, negative and neutral images. Further, eye movement data shows reduced search patterns for wrongly selected stimuli containing emotional content.Conclusions: The results of this study suggest that it is feasible to use emotional content in a VR based cognitive-motor task for attention and memory training after stroke. Stroke survivors showed less attention towards negative information, exhibiting reduced visual search patterns and more false memories. We have also shown that the use of emotional stimuli in a VR task can provide additional information regarding patient's mood and cognitive status. [ABSTRACT FROM AUTHOR]

The current study utilized a large, unselected sample of adolescent twins to examine whether processing speed (PS) is an important shared predictor that accounts for covariance among reading, math, ADHD, and rapid naming (RN). The best fitting model included correlated but distinguishable latent measures of PS, RN, reading, math, inattention, hyperactivity/impulsivity, and academic fluency. PS was a shared predictor across all outcomes, while RN was uniquely associated with reading, fluency, and (albeit weakly) math. The results add to a growing literature suggesting that PS and RN may be important components of comprehensive neuropsychological models of academics, ADHD, and their covariation. [ABSTRACT FROM AUTHOR]

The authors investigated whether contextual failures in schizophrenia are due to deficits in the detection of context or the inhibition of contextually irrelevant information. Eighteen schizophrenia patients and 24 nonpsychiatric controls were tested via a cross-modal semantic priming task. Participants heard sentences containing homonyms and made lexical decisions about visual targets related to the homonyms' dominant or subordinate meanings. When sentences moderately biased subordinate meanings (e.g., the animal enclosure meaning of pen), schizophrenia patients showed priming of dominant targets (e.g., paper) and subordinate targets (e.g., pig). In contrast, controls showed priming only of subordinate targets. When contexts strongly biased subordinate meanings, both groups showed priming only of subordinate targets. The results suggest that inhibitory deficits rather than context detection deficits underlie contextual failures in schizophrenia. [ABSTRACT FROM AUTHOR]

Background: Many studies have shown the impact of acute aerobic exercises (AAE) on cognition in healthy adults or at a pre-dementia stage. Few studies, however, have explored the positive effects of AAE in moderate Alzheimer's disease (ADM) patients.Objective: Evaluating the effect of AAE on cognitive functions in ADM patients.Methods: Overall, 79 (age: 69.62±0.99) ADM patients were recruited. Participants were divided into three groups according to the task: aerobic exercises done alone or combined with cognitive games presented on a screen, and a control group who performed a reading task. The aerobic exercise protocol consisted of a 20-min cycling exercise of moderate intensity, corresponding to 60%of the individual target maximal heart rate recorded in a 6-minute walking test. The participants' cognition was monitored before and after the intervention using the Tower of Hanoi, Digit Span, and Stroop tasks.Results: After the exercise, the participants' attention in both the physical and combined groups improved for the Stroop, the forward and backward Digit Span tasks, as well as the time taken to solve the Tower of Hanoi, although no significant differences were found in the number of moves taken in the latter. By contrast, the control group did not show any significant improvement for most of the cognitive tasks after the reading session.Conclusion: Current evidence suggests that AAE may help to improve cognitive functions in ADM patients. This improvement is enhanced when the exercise is combined with cognitive games. Safe and progressive types of exercises should be promoted among ADM patients. [ABSTRACT FROM AUTHOR]

Background: The model of executive attention proposes that temporal organization, i.e., the time necessary to bring novel tasks to fruition is an important construct that modulates executive control. Subordinate to temporal organization are the constructs of working memory, preparatory set, and inhibitory control.Objective: The current research operationally-defined the constructs underlying the theory of executive attention using intra-component latencies (i.e., reaction times) from a 5-span backward digit test from patients with suspected mild cognitive impairment (MCI).Methods: An iPad-version of the Backward Digit Span Test (BDT) was administered to memory clinic patients. Patients with (n = 22) and without (n = 36) MCI were classified. Outcome variables included intra-component latencies for all correct 5-span serial order responses.Results: Average total time did not differ. A significant 2-group by 5-serial order latency interaction revealed the existence of distinct time epochs. Non-MCI patients produced slower latencies on initial (position 2-working memory/preparatory set) and latter (position 4-inhibitory control) correct serial order responses. By contrast, patients with MCI produced a slower latency for middle serial order responses (i.e., position 3-preparatory set). No group differences were obtained for incorrect 5-span test trials.Conclusion: The analysis of 5-span BDT serial order latencies found distinct epochs regarding how time was allocated in the context of successful test performance. Intra-component latencies obtained from tests assessing mental re-ordering may constitute useful neurocognitive biomarkers for emergent neurodegenerative illness. [ABSTRACT FROM AUTHOR]

The differences in the executive attention network and the related blood oxygen characteristics of the right frontal-parietal network brain area between athletes from interceptive and strategic sport were investigated. Strategic athletes had higher accuracy and longer reaction time (RT) compared with interceptive sports athletes, lower flanker conflict effects on accuracy compared to the other two group. It was accompanied by significant activation of the rdLPFC and the rIFG. Strategic athletes had higher flanker conflict effects on RT compared with interception athletes under the invalid cue condition, which was accompanied by significant activation of the right IFG. The strategic athletes complete the task under the condition of invalid clues indicating top-down control, and which is closely related to the activation of the right frontal-parietal network. [ABSTRACT FROM AUTHOR]

Attention is improved through cognitive rehabilitation. The purpose of the present study was the evaluation of the effect of a paper and pencil program for attention rehabilitation and strengthening (PARS) in children with ADHD. Thirty children with ADHD were randomly divided into two equal intervention and control groups. The intervention group received 12-15 sessions of intervention through PARS. Sustained, selective, and shifting attention, inhibitory control, and working memory were assessed by Persian attention registration, Stroop, color trail making, Go/No-Go, and 1- back tests. Analyses indicated that the experimental group, in comparison with the control group, showed improved selective and sustained attention and the training effects transfers to executive functions, inhibitory control and working memory. The result is discussed in the light of transferability of training effects from attention to executive functions. [ABSTRACT FROM AUTHOR]

Background: In older people with cognitive impairment (CI), executive function (EF) has been associated with motor performance including balance and gait. The literature examining and supporting a relationship between balance performance and other cognitive domains is limited.Objective: To investigate the relationship between global cognition and cognitive domain function and balance performance in older people with CI.Methods: The iFOCIS randomized controlled trial recruited 309 community-dwelling older people with CI. Baseline assessments completed before randomization were used for analyses including the Addenbrooke's Cognitive Examination-III (ACE-III; global cognition) and its individual cognitive domains (attention; memory; verbal fluency; language; visuospatial ability) and the Frontal Assessment Battery (FAB), a measure of EF. A composite balance score was derived from postural sway and leaning balance tests.Results: In linear regression analyses adjusted for covariates, global cognition and each cognitive domain were significantly associated with balance performance. EF (verbal fluency; β= -0.254, p < 0.001, adjusted R2 = 0.387) and visuospatial ability (β= -0.258, p < 0.001, adjusted R2 = 0.391) had the strongest associations with balance performance. In a comprehensively adjusted multivariable model including all of the ACE-III cognitive domains, visuospatial ability and EF (verbal fluency) were independently and significantly associated with balance performance.Conclusion: Poorer global cognition and cognitive domain function were associated with poorer balance performance in this sample of people with CI. Visuospatial ability and EF were independently associated with balance, highlighting potential shared neural networks and the role higher-level cognitive processes and spatial perception/processing play in postural control. [ABSTRACT FROM AUTHOR]

Objective: Mind wandering, the unintended shifting of attention from a task, has been previously associated with symptoms of ADHD. To this end, we conducted a literature search to investigate the association between mind wandering and ADHD. Method: We conducted a systematic search of the literature of relevant articles assessing mind wandering and ADHD in PubMed, PsycINFO/OVID, and Medline. Included were original articles in English that had operationalized definitions of ADHD and mind wandering, adequate sample size, and reliance on statistical evaluation of findings. Excluded were reviews, opinions, and case reports. Results: Only nine studies met our a priori inclusion and exclusion criteria (N = 8 in adults; N = 1 in pediatrics). Findings suggest that ADHD is frequently associated with spontaneous mind wandering and when present heralds more functional impairments. Conclusion: The limited research on mind wandering in ADHD indicates that it is prevalent and morbid supporting further research on the subject. [ABSTRACT FROM AUTHOR]

The number of older drivers with dementia is rising with the aging of the adult population. A public health issue is growing because of concerns about the motor vehicle accident risk posed by drivers with dementia of the Alzheimer's type (DAT) and other progressive, degenerative dementias. However, little is known about the specific perceptual/cognitive deficits contributing to impaired driving in DAT. The present paper proposes, on both theoretical and empirical grounds, that attentional skills in relation to driving should be examined in older adults with and without DAT. Such investigations should focus on normal older adults and those in the mild, early stages of dementia because the latter are the most likely among the dementia population to be still driving. Evidence is presented indicating (1) that motor vehicle accident rates are related to performance on information-processing measures of different components of attention; (2) that this relationship is greatest for measures of the switching of selective attention and less for that of divided and sustained attention (vigilance); and (3) that many of these same attentional functions, and particularly the switching of visual selective attention, are impaired in the early stages of DAT and thus may contribute to increased accident risk. Further studies of cognitive and driving performance in older drivers are necessary to establish that the attentional impairments found in mild DAT contribute to increased accident risk. Implications of these findings for driver assessment, education, and training are discussed. [ABSTRACT FROM AUTHOR]

Selecting the appropriate display format for time-constrained tasks is the focus of the research presented in this paper. The effect of time stress on operator performance was assessed by manipulating the time available to process the display. Twenty people were trained as operators and instructed to identify the state of a system using either a digital display or a polygon display. Participants were required to reach a prespecified criterion in training and were then tested under time-constrained conditions. Time constraints were set at 100%, 50%, and 25% of each person's mean unpaced response times obtained during training. Results showed that response to the time constrained conditions was significantly affected by uncertainty and the type of display format. Discussion focuses on the effects of time stress on performance and the selection of displays for time-constrained tasks. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study of the effects of individual sound parameters on perceived (psychoacoustic) urgency. Experimental Series 1 showed that fundamental frequency, harmonic series, amplitude envelope shape, and delayed harmonics all have clear and consistent effects on perceived urgency. Experimental Series 2 showed that temporal and melodic parameters such as speed, rhythm, pitch range, and melodic structure also have clear and consistent effects on perceived urgency. The final experiment tested a set of 13 auditory warnings generated by an application of the earlier experimental findings. The urgency rank ordering of this warning set was predicted, and the correlation between the predicted and the obtained order was highly significant. The results of these experiments have a widespread application in the improvement of existing auditory warning systems and the design of new systems, where the psychoacoustic and psychological appropriateness of warnings could be enhanced. [ABSTRACT FROM AUTHOR]

This paper examines the effects of stress on sustained attention. With recognition of the task itself as the major source of cognitive stress, a dynamic model is presented that addresses the effects of stress on vigilance and, potentially, a wide variety of attention-demanding performance tasks. [ABSTRACT FROM AUTHOR]

Objectives: Spatial neglect may result from disruption of sensory-attentional systems that spatially allocate perceptual resources and the motor-intentional systems that direct exploration and action. Previous studies have suggested that the line bisection task is more sensitive to sensory-attentional disorders and the cancellation task to motor-intentional disorders. A new technique was developed that allows the dissociation of sensory-attentional and motor-intentional deficits in both tasks and thereby allows comparison of these tasks.Methods: Ten patients with right hemispheric injury and hemispatial neglect performed line bisection and cancellation tasks while viewing stimuli on closed circuit TV. Direct view of the exploring hand and the target was precluded; the TV monitor guided performance. The direct condition made the direction of hand movement on the table (workspace) congruent with that on the monitor. Inverting the camera produced the indirect condition wherein the lateral movement in the workspace occurred in the opposite direction on the monitor.Results: On the cancellation task, five patients marked targets in the right workspace in the direct condition but the left workspace in the indirect condition, indicating sensory-attentional neglect. However, four other patients cancelled targets only in the right workspace in both conditions, failing to explore the left workspace, suggesting motor-intentional neglect. A patient who performed ambiguously may have elements of both types of neglect. Only two out of five patients designated as sensory-attentional in cancellation tasks showed sensory neglect on line bisection. The other three patients, as well as patients defined as motor-intentional by cancellation performance, exhibited motor-intentional neglect on line bisection.Conclusion: The designation of sensory-attentional versus motor-intentional neglect therefore, in part, depends on task specific demands. [ABSTRACT FROM AUTHOR]

Objective: We examined whether children with attention-deficit/hyperactivity disorder (ADHD) differ from children without ADHD in attention, executive functions, and motor skills and whether measures of parents' perceptions and children's performance reveal comparable results. Method: About 52 children with ADHD and 52 children without ADHD aged 6 to 13 years completed performance-based measures of attention, executive functions, and motor skills. Parents completed questionnaires to rate their children's skills. Results: Parent questionnaires but not performance-based measures revealed higher inattention and lower executive function skills in children with ADHD compared to controls. For motor skills, both measurement methods revealed lower mean values and a higher number of children showing an impairment in the ADHD group. Parent-reported difficulties but not performance-based measures were related to the presence of an ADHD diagnosis. Conclusion: Our findings suggest that considering both parent questionnaires and performance-based measures will lead to a comprehensive picture of a child's strengths and difficulties. [ABSTRACT FROM AUTHOR]

Objective: This preliminary study investigated effectiveness of neurocognitive training on academic engagement (AET) for children with ADHD. The training approach targeted working memory, inhibitory control, and attention/relaxation (via brain electrical activity). Method: A reversal design with a 2-week follow-up was used to assess the effectiveness of the treatment on two children with diagnosed ADHD in two learning settings. Direct observation was used to collect academic-related behavior. Results: Improvements in on-task expected behavior (ONT-EX) and general AET, as well as reductions in off-task motor activity (OFF-MA) and off-task passive behavior (OFF-PB) were observed for both students over baselines and across the settings. Moreover, differences in behavioral change were found between participants and settings. Conclusion: These findings support using the treatment for improving academic performance of children with ADHD. Future studies may investigate influences of contextual differences, nontreatment variables, or adult's feedback during the training session on treatment effectiveness. [ABSTRACT FROM AUTHOR]

US military veterans who have histories of mild traumatic brain injury (mild TBI) are evaluated and treated in specialized clinics in the Veterans Health Administration (VA). In this ethnography of one such clinic, I explore the problem of veterans' forgetting. I focus on doctors' strategy of actively drawing attention to the ambiguous causes of forgetting to reposition past head injuries as among many possible explanations, including posttraumatic stress, pain, and everyday distractions. This leveraging of ambiguity as therapy highlights both the utility of and tensions inherent in the expansive clinical gaze of therapeutic medicine. [ABSTRACT FROM AUTHOR]

In this paper we argue that predictive processing (PP) theory cannot account for the phenomenon of affect-biased attention - prioritized attention to stimuli that are affectively salient because of their associations with reward or punishment. Specifically, the PP hypothesis that selective attention can be analyzed in terms of the optimization of precision expectations cannot accommodate affect-biased attention; affectively salient stimuli can capture our attention even when precision expectations are low. We review the prospects of three recent attempts to accommodate affect with tools internal to PP theory: Miller and Clark's (2018) embodied inference; Seth's (2013) interoceptive inference; and Joffily and Coricelli's (2013) rate of change of free energy. In each case we argue that the account does not resolve the challenge from affect-biased attention. For this reason, we conclude that prediction error minimization is not sufficient to explain all mental phenomena, contrary to the claim that the PP framework provides a unified theory of all mental phenomena or the brain's cognitive functioning. Nevertheless, we suggest that empirical investigation of the interaction between affective salience and precision expectations should prove helpful in understanding the limits of PP theory, and may provide new directions for the application of a Bayesian perspective to perception. [ABSTRACT FROM AUTHOR]

Background: Few consistent data are available in relation to the cognitive and neuropsychological processes involved in sluggish cognitive tempo (SCT) symptoms. The objective of this study was to determine the association of working memory and attentional networks with SCT symptoms in primary schoolchildren. Methods: The participants were schoolchildren aged 7 to 10 years (n = 183) from primary schools in Catalonia (Spain). All the participants completed a working memory task (n-back) and an attentional network task (ANT). Their parents completed an SCT-Child Behavior Checklist self-report and a questionnaire concerning sociodemographic variables. Teachers of the participants provided information on ADHD symptoms and learning determinants. Results: SCT symptoms were correlated with lower scores in both the n-back and ANT. In multivariate regression analysis, SCT symptoms were associated with slower hit reaction times from the ANT. Conclusions: Our results suggest that SCT symptoms are associated with a neuropsychological profile that is different from the classical ADHD profile and characterized by slower reaction times. [ABSTRACT FROM AUTHOR]

Objective: The present study strove to distinguish traffic-related glances away from the forward roadway from non-traffic-related glances while assessing the minimum amount of visual information intake necessary for safe driving in particular scenarios.Background: Published gaze-based distraction detection algorithms and guidelines for distraction prevention essentially measure the time spent looking away from the forward roadway, without incorporating situation-based attentional requirements. Incorporating situation-based attentional requirements would entail an approach that not only considers the time spent looking elsewhere but also checks whether all necessary information has been sampled.Method: We assess the visual sampling requirements for the forward view based on 25 experienced drivers' self-paced visual occlusion in real motorway traffic, dependent on a combination of situational factors, and compare these with their corresponding glance behavior in baseline driving.Results: Occlusion durations were on average 3 times longer than glances away from the forward roadway, and they varied substantially depending on particular maneuvers and on the proximity of other traffic, showing that interactions with nearby traffic increase perceived uncertainty. The frequency of glances away from the forward roadway was relatively stable across proximity levels and maneuvers, being very similar to what has been found in naturalistic driving.Conclusion: Glances away from the forward roadway proved qualitatively different from occlusions in both their duration and when they occur. Our findings indicate that glancing away from the forward roadway for driving purposes is not the same as glancing away for other purposes, and that neither is necessarily equivalent to distraction. [ABSTRACT FROM AUTHOR]

Objective: To assess the attentional demand of different contextual factors in driving.Background: The attentional demand on the driver varies with the situation. One approach for estimating the attentional demand, via spare capacity, is to use visual occlusion.Method: Using a 3 × 5 within-subjects design, 33 participants drove in a fixed-base simulator in three scenarios (i.e., urban, rural, and motorway), combined with five fixed occlusion durations (1.0, 1.4, 1.8, 2.2, and 2.6 s). By pressing a microswitch on a finger, the driver initiated each occlusion, which lasted for the same predetermined duration within each trial. Drivers were instructed to occlude their vision as often as possible while still driving safely.Results: Stepwise logistic regression per scenario indicated that the occlusion predictors varied with scenario. In the urban environment, infrastructure-related variables had the biggest influence, whereas the distance to oncoming traffic played a major role on the rural road. On the motorway, occlusion duration and time since the last occlusion were the main determinants.Conclusion: Spare capacity is dependent on the scenario, selected speed, and individual factors. This is important for developing workload managers, infrastructural design, and aspects related to transfer of control in automated driving.Application: Better knowledge of the determinants of spare capacity in the road environment can help improve workload managers, thereby contributing to more efficient and safer interaction with additional tasks. [ABSTRACT FROM AUTHOR]

In this paper, we embed two types of attention modules in the dilated fully convolutional network (FCN) to solve biomedical image segmentation tasks efficiently and accurately. Different from previous work on image segmentation through multiscale feature fusion, we propose the fully convolutional attention network (FCANet) to aggregate contextual information at long-range and short-range distances. Specifically, we add two types of attention modules, the spatial attention module and the channel attention module, to the Res2Net network, which has a dilated strategy. The features of each location are aggregated through the spatial attention module, so that similar features promote each other in space size. At the same time, the channel attention module treats each channel of the feature map as a feature detector and emphasizes the channel dependency between any two channel maps. Finally, we weight the sum of the output features of the two types of attention modules to retain the feature information of the long-range and short-range distances, to further improve the representation of the features and make the biomedical image segmentation more accurate. In particular, we verify that the proposed attention module can seamlessly connect to any end-to-end network with minimal overhead. We perform comprehensive experiments on three public biomedical image segmentation datasets, i.e., the Chest X-ray collection, the Kaggle 2018 data science bowl and the Herlev dataset. The experimental results show that FCANet can improve the segmentation effect of biomedical images. The source code models are available at https://github.com/luhongchun/FCANet. [ABSTRACT FROM AUTHOR]

Human performance in complex multiple-task environments depends critically on the interplay between cognitive control and cognitive capacity. In this paper we propose a tractable computational model of how cognitive control and capacity influence the speed and accuracy of decisions made in the event-based prospective memory (PM) paradigm, and in doing so test a new quantitative formulation that measures two distinct components of cognitive capacity (gain and focus) that apply generally to choices among two or more options. Consistent with prior work, individuals used proactive control (increased ongoing task thresholds under PM load) and reactive control (inhibited ongoing task accumulation rates to PM items) to support PM performance. Individuals used cognitive gain to increase the amount of resources allocated to the ongoing task under time pressure and PM load. However, when demands exceeded the capacity limit, resources were reallocated (shared) between ongoing task and PM processes. Extending previous work, individuals used cognitive focus to control the quality of processing for the ongoing and PM tasks based on the particular demand and payoff structure of the environment (e.g., higher focus for higher priority tasks; lower focus under high time pressure and with PM load). Our model provides the first detailed quantitative understanding of cognitive gain and focus as they apply to evidence accumulation models, which - along with cognitive control mechanisms - support decision-making in complex multiple-task environments. [ABSTRACT FROM AUTHOR]

This study utilized data from the Avon Longitudinal Study of Parents and Children (N = 14,860) to examine whether early-life family income (age 0-5) predicted long-term academic achievement (age 16-18) and to investigate the role of executive function (EF) assessed multiple times across age 7-11 in explaining this association. Task-based EF was a significant mediator between early-life family income and later academic achievement in every model. This mediating pathway persisted when adjusting for a comprehensive panel of covariates including verbal IQ, sex, family income at ages 8 and 18, and early-life temperament. Additionally, teacher-rated and parent-rated EF mediated in some models. Overall, these findings suggest that childhood EF may play an important role in perpetuating income-based educational disparities. [ABSTRACT FROM AUTHOR]

Background: Prevention of age-related cognitive decline and depression is becoming urgent because of rapid growing aging populations. Effects of vagal nerve activation on brain function by food ingredients are inadequately investigated; matured hop bitter acid (MHBA) administration reportedly improves cognitive function and depression via vagal nerve activation in model mice.Objective: We investigated the effects of MHBA supplementation on cognitive function and mood state in healthy older adults with perceived subjective cognitive decline.Methods: Using a randomized double-blind placebo-controlled trial design, 100 subjects (aged 45-69 years) were randomly assigned into placebo (n = 50) and MHBA (n = 50) groups, and received placebo or MHBA capsules daily for 12 weeks.Results: Symbol Digit Modalities Test (SDMT) score assessing divided attention at week 12 was significantly higher (p = 0.045) and β-endorphin at week 12 was significantly lower (p = 0.043) in the subjects receiving MHBA. Transthyretin in serum, a putative mild cognitive impairment marker, was significantly higher at week 12 in the MHBA group than in the placebo group (p = 0.048). Subgroup analysis classified by the subjective cognitive decline questionnaire revealed that in addition to improved SDMT scores, memory retrieval assessed using the standard verbal paired-associate learning tests and the Ray Verbal Learning Test at week 12 had significantly improved in the subgroup with perceived subjective cognitive decline and without requirement for medical assistance in the MHBA group compared with that in the placebo group.Conclusion: This study suggested that MHBA intake improves cognitive function, attention, and mood state in older adults. [ABSTRACT FROM AUTHOR]

Objective: The study aimed to investigate the reciprocal and temporal relations between ADHD symptoms and emotional problems in school-age children. Method: This 1-year longitudinal study with a four-wave design included 1,253 children and adolescents (254 third graders, 281 fifth graders, and 718 eighth graders; 50.9% boys). ADHD symptoms and emotional problems were measured using parent report of the Swanson, Nolan, and Pelham, Version IV Scale and Strengths and Difficulties Questionnaire. Results: Cross-lagged panel analyses indicated that both inattention and hyperactivity/impulsivity symptoms were associated with emotional problems over the 1-year period. However, only inattention symptoms demonstrated a transactional relationship with emotional problems, such that inattention predicted future emotional problems, which in turn led to increases in inattention symptoms. Conclusion: Our findings highlight the transactional and dynamic interplay between inattention symptoms and emotional problems and support the mechanistic role of inattention symptoms in the development and persistence of emotional problems in school-age children. [ABSTRACT FROM AUTHOR]

Ethnographies of bodies have become entry points for understanding the sensorially rich ways that worlds are generated and lived. Here, I adduce a slow-paced ethnographic mode that centers how bodily pain and touch orient attention, with a focus on gendered and racialized violence in the suburbs of Rio de Janeiro. In doing so, I make explicit the expectation in Rio's urban governance that resilience means toughening through pain. In turn, I detail how Pentecostal practices of 'healing touch' link pain and hope together, demonstrating the religious work, care, and governance involved in producing and maintaining hope under conditions of violence. [ABSTRACT FROM AUTHOR]

Introduction and Objectives: The ability to adapt to new task demands flexibly and to stabilise performance in the presence of distractors is termed cognitive control and is mediated by dopaminergic and cholinergic neurotransmission. We aimed to test the hypothesis that the effect of the cholinergic agonist nicotine on cognitive control depends on baseline dopamine levels.Methods: Thirty-eight healthy non-smokers (16 males; Mage=24.05 years) performed a cognitive control task including distractor and switch trials twice. Subjects were split into two parallel groups. One group received 2 g of L-tyrosine two hours prior to testing to manipulate dopamine availability experimentally, while the other group received placebo on both days. One hour later, both groups received in a within-subject design: on one day, a 7 mg nicotine patch; on the other day, a matched placebo. Response time costs for distractor and switch trials served as measures of cognitive stability and flexibility.Results: Nicotinic modulation reduced response time costs in switch trials and increased costs in distractor trials (nicotine×condition, p=0.027) with a trend-wise interaction between nicotine, L-tyrosine and trial type (nicotine×L-tyrosine×condition, p=0.068), which was due to stronger nicotine effects under L-tyrosine.Conclusions: Our data provide preliminary evidence that nicotine has opponent effects on cognitive stability and flexibility. Subjects who received the dopamine precursor L-tyrosine were more prone to nicotine effects on behaviours, which are improvements in cognitive flexibility at the cost of decreased cognitive stability. [ABSTRACT FROM AUTHOR]

The aim of this work was to study the relationship between temperament and signs of psychopathology in typically developing toddlers. More specifically, Attentional Deficit Hyperactivity Disorder (ADHD) and Oppositional Defiant Disorder (ODD) symptoms were analyzed in connection with fine-grained temperament dimensions. The sample was composed of 65 toddlers aged between 18 and 35 months. Bivariate correlations showed that higher levels of negative emotionality and approach tendencies, and lower levels of inhibitory control, were related to more ADHD and ODD manifestations. Bivariate correlations also indicated unique associations: lower levels of soothability were associated with higher ODD symptoms, whereas lower attentional focusing and low-intensity pleasure were related with higher ADHD symptoms. Additionally, regression and path analysis models indicated that ADHD was predominantly associated with attentional focusing and motor activation whereas ODD was most closely related to frustration. Our findings highlight the relevance of studying early correlates of psychopathological manifestations to identify children who could benefit from prevention and early intervention programs. [ABSTRACT FROM AUTHOR]

Background: Subarachnoid hemorrhage (SAH) is a devastating disease associated with high mortality and morbidity. Besides neurological sequelae, neuropsychological deficits largely contribute to patients' long-term quality of life. Little is known about the pituitary gland volume (PGV) after SAH compared to healthy referents and the association of PGV with long-term outcome including cognitive function.Methods: Sixty consecutive non-traumatic SAH patients admitted to the neurological intensive care unit between 2010 and 2014 were enrolled. 3-Tesla magnetic resonance imagining was performed at baseline (16 days) and 12 months after SAH to measure PGV semi-automatically using the software iPlan Net 3.5.0. PGV was compared to age and sex matched healthy referents. The difference between baseline and 1-year-PGV was classified as increase (> 20 mm3 PGV increase), stable (± 20 mm3), or decrease (> 20 mm3 PGV decrease). In addition, total intracerebral volume was calculated. Neuropsychological testing was applied in 43 SAH patients at 1-year follow up encompassing several domains (executive, attention, memory) and self-assessment (questionnaire for self-perceived deficits in attention [German: FEDA]) of distractibility in mental processes, fatigue and decrease in motivation. Multivariable regression with multivariable generalized linear models was used for comparison of PGVs and for subgroup analysis to evaluate a potential association between PGV and neuropsychological outcome.Results: Patients were 53 years old (IQR = 44-63) and presented with a median Hunt&Hess grade of 2 (IQR = 1-3). SAH patients had a significantly lower PGV both at baseline (360 ± 19 mm3, p < 0.001) and 1 year (367 ± 18 mm3p < 0.001) as compared to matched referents (mean 505 ± 18 mm3). PGV decreased by 75 ± 8 mm3 in 28 patients, increased by 120 ± 22 mm3 in 22 patients and remained stable in 10 patients at 1-year follow-up. PGV in patients with PGV increase at 12 months was not different to healthy referents (p = 0.062). Low baseline PGV was associated with impaired executive functions at 1 year (adjOR = 8.81, 95%-CI = 1.46-53.10, p = 0.018) and PGV decrease within 1 year was associated with self-perceived worse motivation (FEDA; Wald-statistic = 6.6, df = 1, p = 0.010).Conclusions: Our data indicate significantly lower PGVs following SAH. The association of sustained PGV decrease with impaired neuropsychological long-term outcome warrants further investigations including neuroendocrine hormone measurements. [ABSTRACT FROM AUTHOR]

Objective: The efficacy of n-back training for children with attention deficit hyperactivity disorder (ADHD) was tested in a randomized controlled trial. Method: 41 children aged 7 to 14 years with ADHD were trained on an n-back task, and their performance was compared with that of an active control group (n = 39) who were trained on a general knowledge and vocabulary task. Results: The experimental group demonstrated transfer of training to a nontrained n-back task as well as to a measure of inhibitory control. These effects were correlated with the magnitude of training gains. Conclusion: Our results suggest that n-back training may be useful in addressing some of the cognitive and behavioral issues associated with ADHD. [ABSTRACT FROM AUTHOR]

Neonatal risk factors have been associated with atypical development in various areas of social communication, including joint attention (JA), but little is known about factors in the early caregiving environment that can modify the negative implications of neonatal risk. The present study examines the links between neonatal risk and infants' JA, while considering the mediating role of maternal sensitive-responsiveness and the moderating roles of stressful contexts. One hundred and eighty-two families with infants (50% female) born in a wide range of gestational ages and birthweights participated in the study. Neonatal risk was assessed shortly after birth using three indicators: birthweight, gestational age, and degree of medical risk. At age 6 months, maternal sensitive-responsiveness to infants' foci of attention was rated and maternal anxiety and household chaos were measured. Infants' JA behaviors were assessed at age 12 months. A moderated-mediation model revealed that maternal anxiety symptoms and household chaos moderated the links between neonatal risk, maternal sensitive-responsiveness, and infants' responding to JA. Specifically, neonatal risk was related to less maternal sensitive-responsiveness only when maternal anxiety symptoms were above average levels, but not when anxiety symptoms were low. Moreover, maternal sensitive-responsiveness was positively related to infants' responding to JA behaviors when household chaos was low but not when it was high. These findings highlight the complex nature of the links between infants' early biological risk and caregiving environments in the development of social communication skills. [ABSTRACT FROM AUTHOR]

It is almost a cultural truism that erotic images attract our attention, presumably because paying attention to erotic stimuli provided our ancestors with mating benefits. Attention, however, can be narrowly defined as visuospatial attention (keeping such stimuli in view) or more broadly as cognitive attention (such stimuli taking up one's thoughts). We present four independent studies aiming to test the extent to which erotic images have priority in capturing visuospatial versus cognitive attention. Whereas the former would show in quicker reactions to stimuli presented in locations where erotic images appeared previously, the latter causes delayed responding after erotic images, independent of their location). To this end, we specifically modified spatial cueing tasks to disentangle visuospatial attention capture from general sexual content-induced delay (SCID) effects-a major drawback in the previous literature. Consistently across all studies (total N = 399), we found no evidence in support of visuospatial attention capture but reliably observed an unspecific delay of responding for trials in which erotic images appeared (irrespective of cue location). This SCID is equally large for heterosexual men and women and reliably associated with their self-reported sexual excitability. [ABSTRACT FROM AUTHOR]

Background: Patients with functional movement disorders also typically have functional somatic symptoms, including pain, fatigue, and sensory disturbance. A potentially unifying mechanism for such symptoms is a failure in processing of sensory inputs. Prepulse inhibition is a neurophysiological method that allows for the study of preconscious somatosensory processing.Objective: The objective of this study was to assess prepulse inhibition in patients with functional movement disorders and healthy control subjects.Methods: We analyzed the effect of a weak electrical stimulus to the index finger (prepulse) on the magnitude of the R2 response of the blink reflex induced by electrical stimuli delivered to the supraorbital nerve in 22 patients with clinically established functional movement disorders and 22 matched controls. Pain, depression, anxiety, and obsessive-compulsive symptoms were assessed using self-rated questionnaires. In addition, in patients we assessed motor symptom severity.Results: Prepulses suppressed the R2 response of the blink reflex in both groups, by 36.4% (standard deviation: 25.6) in patients and by 67.3% (standard deviation: 16.4) in controls. This difference was significant (P < 0.001). There was no significant correlation between motor and nonmotor symptom measures and prepulse inhibition size.Conclusions: Impaired prepulse inhibition of the blink reflex suggests an abnormal preconscious processing of somatosensory inputs, which can be interpreted within predictive coding accounts of both functional movement disorders and functional somatic syndromes. Our results, along with previous findings of a reduced prepulse inhibition in fibromyalgia syndrome, support a possible unified pathophysiology across functional neurological and somatic syndromes with noteworthy implications for diagnostic classification and development of novel biomarkers and treatments. © 2019 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Objective: The identification of modifiable lifestyle factors to preserve cognitive function in older individuals becomes increasingly of importance. This study examines whether word puzzle use is related to cognitive function in older adults.Methods: Cognitive data from 19 078 cognitively healthy individuals aged 50 to 93 years enrolled into the online PROTECT study were evaluated for self-reported frequency of performing word puzzles on a six-point scale, ranging from "more than once per day" to "never". Nine cognitive tests covered a range of domains including focussed and sustained attention, information processing, executive function, working memory, and episodic memory. Analyses of covariance were used to determine any differences between the six response groups.Results: Each of the 14 cognitive measures analysed showed highly statistically significant main effects of the frequency of performing word puzzles. For each measure, the group who never performed word puzzles performed most poorly, with the group who reported occasional puzzle use also performing more poorly than virtually every other group. Measures of speed provided the greatest discriminations, with a grammatical reasoning score differentiating the two highest frequency groups, performing word puzzles daily or more than once daily.Conclusions: The frequency of word puzzle use is directly related to cognitive function in adults aged 50 and over. Future work needs to determine whether engaging in such puzzles can favourably influence cognitive trajectory with age. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to understand how to secure driver supervision engagement and conflict intervention performance while using highly reliable (but not perfect) automation.Background: Securing driver engagement-by mitigating irony of automation (i.e., the better the automation, the less attention drivers will pay to traffic and the system, and the less capable they will be to resume control) and by communicating system limitations to avoid mental model misconceptions-is a major challenge in the human factors literature.Method: One hundred six drivers participated in three test-track experiments in which we studied driver intervention response to conflicts after driving highly reliable but supervised automation. After 30 min, a conflict occurred wherein the lead vehicle cut out of lane to reveal a conflict object in the form of either a stationary car or a garbage bag.Results: Supervision reminders effectively maintained drivers' eyes on path and hands on wheel. However, neither these reminders nor explicit instructions on system limitations and supervision responsibilities prevented 28% (21/76) of drivers from crashing with their eyes on the conflict object (car or bag).Conclusion: The results uncover the important role of expectation mismatches, showing that a key component of driver engagement is cognitive (understanding the need for action), rather than purely visual (looking at the threat), or having hands on wheel.Application: Automation needs to be designed either so that it does not rely on the driver or so that the driver unmistakably understands that it is an assistance system that needs an active driver to lead and share control. [ABSTRACT FROM AUTHOR]

Objective: To compare the effects of different surgical approaches for selective amygdalohippocampectomy in patients with pharmacoresistant mesial temporal lobe epilepsy with regard to the neuropsychological outcome and to replicate an earlier study employing a matched-pair design.Method: 47 patients were randomised to subtemporal versus transsylvian approaches. Memory, language, attentional and executive functions were assessed before and 1 year after surgery. Multivariate analyses of variance (MANOVAs) with presurgical and postsurgical assessments as within-subject variables and approach and side of surgery as between-subject factors were calculated. Additionally, the frequencies of individual performance changes based on reliable change indices were analysed.Results: Seizure freedom International League Against Epilepsy (ILAE) 1a, was achieved in 62% of all patients without group difference. MANOVAs revealed no significant effects of approach on cognition. Tested separately for each parameter, verbal recognition memory declined irrespective of approach. Post hoc tests revealed that on group level, the subtemporal approach was associated with a worse outcome for verbal learning and delayed free recall as well as for semantic fluency. Accordingly, on individual level, more patients in the subtemporal group declined in verbal learning. Left side of surgery was associated with decline in naming regardless of approach.Conclusion: The main analysis did not confirm the effects of approach on memory outcome seen in our previous study. Post hoc testing, however, showed greater memory losses with the subtemporal approach. Previous findings were replicated for semantic fluency. The discrepant results are discussed on the background of the different study designs. [ABSTRACT FROM AUTHOR]

Typically, falls in older adults occur when 2 tasks are performed simultaneously, due to the increased motor demand required to maintain stability and attention to perform the other task. The authors' purpose was to investigate walking while grasping, transporting, and placing a dowel on a predetermined target while manipulating difficulty levels of the manual task. Faller and nonfaller older adults performed a walking block (manual tasks combined with gait) and a stationary block (upright stance combined with manual tasks). The manual task involved grasping, transporting, and placing the dowel over a target. The results showed that fallers underperformed when compared with nonfallers in the task of placing the dowel over the target. The main difference observed between the groups was found in the condition that required allocation of attention between tasks and greater accuracy in the final placement of the object. Fallers showed gait stability similar to the nonfallers, but fallers were less accurate than nonfallers in the object placement task, especially for the highest level of difficulty. Thus, fallers seem to use a stability-first strategy. Fallers had problems in executing the manual tasks, which suggests a more global change in motor behavior rather than specific changes to balance control. [ABSTRACT FROM AUTHOR]

Subjective memory complaints (SMC) may represent the preclinical phase of mild cognitive impairment (MCI) due to Alzheimer's disease. Dementia/MCI have been described with a high prevalence in Parkinson's disease (PD), but whether SMC may predict the development of cognitive impairment has been barely explored. To evaluate the frequency and clinical correlates of isolated SMC (PD-SMC) or within the construct of MCI in subjects with PD, 147 PD patients from the PArkinson's disease COgnitive impairment Study (PACOS) were consecutively recruited for the study. This is a multicenter study involving two Movement Disorder Centers in south Italy. All subjects underwent comprehensive neuropsychological evaluation and PD-MCI was diagnosed according to Litvan's criteria. The Memory Assessment Clinics Questionnaire was used to assess SMC. Logistic regression analysis, adjusted for demographics and significant covariates, was used to evaluate clinical differences between groups. Forty-two (28.6%) individuals presented with PD without SMC and/or MCI (PDw), 40 (27,2%) with PD-SMC, 48 (32,6%) PD-SMC-MCI, and 17 (11,6%) PD-MCI without SMC (PD-MCI). When compared to PDw, PD-SMC was significantly associated with anxiety (OR = 3.93, 95% CI = 1.18-13.03), while PD-SMC-MCI related to motor progression (OR = 5.29, 95% CI = 1.12-24.86), and instrumental disability (OR = 6.98, 95% CI = 2.08-23.38). About 60% of patients showed SMC, in isolation or within the MCI frame. The role of SMC in PD seems to have a different etiology depending on the presence/absence of MCI. In particular, PD-SMC would represent a subjective reaction to the disease, while PD-SMC-MCI would depict motor progression and disability. [ABSTRACT FROM AUTHOR]

Objective: The present research relies on 2 main objectives. The first is to investigate whether latent model analysis through a structural equation model can be implemented on driving simulator data in order to define an unobserved driving performance variable. Subsequently, the second objective is to investigate and quantify the effect of several risk factors including distraction sources, driver characteristics, and road and traffic environment on the overall driving performance and not in independent driving performance measures.Methods: For the scope of the present research, 95 participants from all age groups were asked to drive under different types of distraction (conversation with passenger, cell phone use) in urban and rural road environments with low and high traffic volume in a driving simulator experiment. Then, in the framework of the statistical analysis, a correlation table is presented investigating any of a broad class of statistical relationships between driving simulator measures and a structural equation model is developed in which overall driving performance is estimated as a latent variable based on several individual driving simulator measures.Results: Results confirm the suitability of the structural equation model and indicate that the selection of the specific performance measures that define overall performance should be guided by a rule of representativeness between the selected variables. Moreover, results indicate that conversation with the passenger was not found to have a statistically significant effect, indicating that drivers do not change their performance while conversing with a passenger compared to undistracted driving. On the other hand, results support the hypothesis that cell phone use has a negative effect on driving performance. Furthermore, regarding driver characteristics, age, gender, and experience all have a significant effect on driving performance, indicating that driver-related characteristics play the most crucial role in overall driving performance.Conclusions: The findings of this study allow a new approach to the investigation of driving behavior in driving simulator experiments and in general. By the successful implementation of the structural equation model, driving behavior can be assessed in terms of overall performance and not through individual performance measures, which allows an important scientific step forward from piecemeal analyses to a sound combined analysis of the interrelationship between several risk factors and overall driving performance. [ABSTRACT FROM AUTHOR]