Assessment Of Reaction Time Research Articles

Augmented reality safety warnings in roadway work zones: Evaluating the effect of modality on worker reaction times

Given the aging highway infrastructure requiring extensive rebuilding and enhancements, and the consequent rise in the number of work zones, there is an urgent need to develop advanced safety systems to protect workers. While Augmented Reality (AR) holds significant potential for delivering warnings to workers, its integration into roadway work zones remains relatively unexplored. The primary objective of this study is to improve safety measures within roadway work zones by conducting an extensive analysis of how different combinations of multimodal Augmented Reality (AR) warnings influence the reaction times of workers. This paper addresses this gap through a series of experiments that aim to replicate the distinctive conditions of roadway work zones, both in real-world and virtual reality environments. Our approach comprises three key components: an advanced AR system prototype, a VR simulation of AR functionality within the work zone environment, and the Wizard of Oz technique to synchronize user experiences across experiments. To assess reaction times, we leverage both the simple reaction time (SRT) technique and an innovative vision-based metric that utilizes real-time pose estimation. By conducting five experiments in controlled outdoor work zones and indoor VR settings, our study provides valuable information on how various multimodal AR warnings impact workers reaction times. Furthermore, our findings reveal the disparities in reaction times between VR simulations and real-world scenarios, thereby gauging VR’s capability to mirror the dynamics of roadway work zones. Furthermore, our results substantiate the potential and reliability of vision-based reaction time measurements. These insights resonate well with those derived using the SRT technique, underscoring the viability of this approach for tangible real-world uses.

Investigation of the playing digital games on shoulder flexibility, muscle strength and reaction speed in volleyball players.

Esports is a natural extension of digital games. Digital games provide a platform for players to showcase their skills, thereby forming the foundation of e-sports. These two domains continuously support each other, demonstrating significant growth in popularity and establishing a solid presence in the competitive landscape. Digital games require high levels of attention, strategy, reflexes, and coordination, offering pathways to reach the pinnacle of competition. The benefits derived from digital games enhance the ability to perform effectively under stress, making them crucial for both physical and mental performance. This study investigates the effects of digital gaming on the physical performance, shoulder flexibility, muscle strength and reaction speed of female volleyball players. A total of 50 female volleyball players took part, who were divided into two groups based on their digital playing habits: Group 1 consisted of female players who played video games for at least 4 h per day in the last 6 months, while Group 2 included those who played <4 h per day. In the study, the Activ5© Handheld Digital Dynamometer was used to measure the strength of the shoulder muscles during various movements, including flexion, hyperextension, abduction, internal rotation and external rotation. In addition, the BlazePod™ trainer device was used to assess reaction times. The results showed that volleyball players who frequently played digitally showed significant improvements in shoulder flexibility, especially in flexion of the non-dominant side. In addition, these players showed faster reaction times than those who played less frequently. However, a significant decrease in hyperextension muscle strength was observed in the group that frequently played digital games. The study highlights that while digital games can improve certain physical skills such as reaction speed and shoulder flexibility, they can also contribute to muscular imbalances or a decrease in muscle strength in certain areas. These findings suggest potential benefits for volleyball players, particularly in movements that require quick reflexes and flexibility, such as serving and spiking. However, the results also raise concerns about potential negative effects on muscle strength and posture, highlighting the need for balanced training programs to mitigate these effects. Further research is needed to investigate the long-term effects of digital games on athletic performance and physical health.

Procedural Memory Deficits in Preschool Children with Developmental Language Disorder in a Spanish-Speaking Population.

This study aimed to compare procedural learning skills between Spanish-speaking preschool children (ages 4 years to 4 years, 11 months) with developmental language disorder (DLD) and their chronologically matched typically developing (TD) peers. Using the serial reaction time (SRT) task, participants (30 children with DLD and 30 TD children) responded to visual stimuli in a sequenced manner over four blocks, followed by a random order block. The task assessed reaction time (RT) and accuracy. The results showed a significant interaction between group and block for RT and accuracy, with children with DLD exhibiting longer RTs and accuracy deficits across blocks. In contrast, the TD group showed higher RT efficiency and accuracy in the sequential blocks and, as expected, decreased performance in the random block according to the experimental manipulation. Overall, the results of this investigation suggest that there was no implicit learning in the DLD group, as indicated by the SRT task paradigms of procedural memory. These findings align with some aspects of the procedural deficit hypothesis (PDH), which suggests that linguistic deficits in the DLD population may derive from a deficit in sequential learning from the procedural memory system domain in the Spanish context.

The influence of selected anthropometric parameters on psychomotor abilities among professional Rugby Union players

BackgroundOne of the most popular varieties of rugby is Rugby Union, in which a team consists of 15 players. Rugby Union is a full-contact sport, and players must demonstrate strength, endurance, speed and agility. During the match, players participate in multiple physical collisions and tackles, short-duration and high-intensity sprinting efforts. In addition, one of the elements affecting the effectiveness of the player’s game can be the reaction time of the rugby player to the visual stimulus and the ability to read the game and react to the situations on the pitch. The level of psychomotor abilities of a person or a player practising sports can be influenced by various factors, including age, body height, body weight, type of sport practised or level of training. The study aimed to analyse the psychomotor abilities of professional rugby union players, investigate the relationship between the selected anthropometric characteristics and psychomotor abilities, and compare obtained results with the control group.MethodsThe study covered 22 players of the Polish National Team (age: 29.3 ± 5.4) and 27 students in the control group (age: 24.3 ± 3.9). The tests were carried out using the Test2Drive computer system of tests. For psychomotor abilities analysis, four tests were used: Simple Reaction Test, Choice Reaction Time Test, Hand-Eye Coordination Test and Spatial Orientation Test. The statistical analysis compares groups using basic statistical measures, and statistically significant differences between groups were checked. In addition, multiple linear regression was used.ResultsThe analysis showed statistically significant differences between the groups in the simple reaction time test and the movement time for the test assessing reaction time with choice and eye-hand coordination. Multiple regression analysis conducted for both groups showed a statistically significant influence of some anthropometric parameters on the examined psychomotor abilities. The calculated multiple regression models had a high fit.ConclusionsThe analysis showed that professional Rugby Union players have shorter movement time than the control group. For reaction time, statistically significant differences were observed only for simple reaction time. Moreover, linear regression analysis showed that body height and weight affect the selected psychomotor abilities.

I can take my eyes off of you: Effect of alexithymia and perceptual load on processing emotional faces

Alexithymic individuals have difficulties processing emotional stimuli, including faces, and may require more resources to process such stimuli. Alexithymia may interact with task characteristics, like perceptual load, which modulates the processing capacity allocated to task-relevant, versus task-irrelevant stimuli. We examined effects of load and distractor type (face, object) and valence (threatening, neutral), and alexithymia on performing a letter-search task. We assessed reaction time, accuracy, and heart rate to index arousal and cognitive effort. Perceptual load, distractor presence, type and valence showed expected effects. Alexithymia did not meaningfully affect reaction time, but was associated with decreased accuracy when distractors were threatening, under low perceptual load. HR did not suggest changes in resources mobilized depending on alexithymia level. Results suggest that alexithymic individuals perceived emotional stimuli and were able to maintain intact reaction time, though this came with a cost in accuracy. Absence of HR effects suggests that no additional resources were recruited to remedy this difficulty. Overall, results suggest that emotional stimuli are perceived in alexithymia at early stages, but resources are not appropriately allocated to prevent performance impairment.

Attentional biases in PTSD, adjustment disorder, and prolonged grief disorder: Attentional interference as a potential transdiagnostic feature

In the ICD-11, posttraumatic stress disorder (PTSD), adjustment disorder (AjD), and prolonged grief disorder (PGD) belong together to the new grouping of disorders specifically associated with stress, which are all characterized by intrusive core symptoms. As previous studies suggest that intrusive symptoms are associated with attentional biases, it is plausible that PTSD, AjD, and PGD are characterized by the same attentional biases as a transdiagnostic feature. The present study investigated 90 participants with symptoms of PTSD, AjD, or PGD. Individuals with a subclinical symptom presentation were also able to participate, resulting in an analogue sample with the group labels aPTSD, aAjD, and aPGD. All participants completed a symptom induction task to provoke symptoms related to attentional biases. Subsequently, a visual search task (VST) was implemented. This test assessed reaction times to trials that include stress-related, neutral, and generally negative stimuli. The VST featured an interference and facilitation condition to investigate different types of attentional biases. Findings showed that all groups were characterized by particularly fast reaction times to trials which included stress-related stimuli in the interference condition, which indicates a reversed attentional interference bias. This bias has not been reported before and is perhaps related to an avoidance behavior.

Impaired neurocognitive functioning 3months following diagnosis of high-risk acute lymphoblastic leukemia: A report from the Children's Oncology Group.

Acute lymphoblastic leukemia (ALL) is the most common pediatric cancer diagnosis. Cognitive late effects develop in 20%-40% of ALL survivors, but the course of declines is unclear. The aim of this paper is to characterize cognitive functioning, and its association with patient-reported outcomes, early in treatment. A total of 483 children with high-risk ALL, aged 6-12years at diagnosis, consented to the neurocognitive study embedded in a prospective therapeutic trial, Children's Oncology Group (COG) AALL1131. A computerized neurocognitive battery (Cogstate) was administered 3months post diagnosis assessing reaction time, visual attention, working memory, visual learning, and executive functioning. Parent-reported executive functioning and patient-reported physical symptoms were also collected. Data from 390 participants (mean age at diagnosis=9.2years, 55.4% male) were obtained. Relatively few patients reported pain (16.0%) or nausea (22.6%), but a majority (68.5%) reported feeling at least some fatigue at testing. Mean Cogstate Z-scores were within normal limits across tasks; however, rates of impairment (Z-scores ≤ -1.5) for reaction time, working memory, visual learning, and visual attention were all higher than expected compared to the standardization sample. Patients reporting fatigue were significantly more likely to have impaired reaction time and visual attention compared to those reporting no fatigue. Findings support feasibility of computerized cognitive assessments and suggest higher-than-expected rates of impaired cognitive performance early during treatment for pediatric ALL, notably within 3months of diagnosis, suggesting intervention efforts may be indicated. These results also highlight acute factors that may impact reliability of "baseline" assessments conducted soon after diagnosis.

Development of a mobile application for assessing reaction time in walking and TUG duration: Concurrent validity in female older adults.

The TUG can be used to distinguish between people who fall and people who don't fall. To evaluate cognitive dual-task performance while walking for fall prediction, TUG-dual was frequently employed. A recent study has created a mobile application that enables simple interaction to provide greater convenience for monitoring the duration of TUG, TUG-subtraction, and reaction time. The research aim was to ascertain the concurrent validity of the mobile application that was developed for the clinical assessment of TUG, TUG-subtraction, and reaction time. Twenty-nine older persons participated in this study. The testing protocol involved the TUG, TUG-subtraction, and reaction time assessment. For TUG and TUG-subtraction, the duration to complete the task was recorded by the APDM Mobility Lab system and the mobile application. For the reaction time tests, the reaction times (msec) were recorded by the Multi Choice Reaction timer and the Mobile application. The TUG durations recorded by the APDM Mobility Lab system were correlated with those recorded by the mobile application to verify the concurrent validity using Pearson's product moment correlation coefficient. Also, the reaction time by the Multi Choice Reaction timer was correlated with the mobile application. Bland-Altman plots were used to explore the existence of any systematic differences between the measurements. Our results showed very strong correlations between the TUG and TUG-subtraction duration derived from the APDM Mobility Lab system and the mobile application (r = 0.96 and 0.96, respectively). For the reaction time, the results showed a moderate correlation between the reaction time derived from the mobile application and the Multi Choice Reaction Timer (r = 0.67). The mobile application, which allows measurement in TUG and TUG-subtraction, is a highly valid tool for TUG duration assessment. However, this application is capable for assess the reaction time with moderate validity for reaction time assessment.

Relationship between Reaction Times and Post-COVID-19 Symptoms Assessed by a Web-Based Visual Detection Task.

Long-COVID is a clinical condition in which patients affected by SARS-CoV-2 usually report a wide range of physical and cognitive symptoms from 3 to 6 months after the infection recovery. The aim of the current study was to assess the link between self-reported long-COVID symptoms and reaction times (RTs) in a self-administered Visual Detection Task (VDT) in order to identify the predictor symptoms of the slowing in reaction times to determine attention impairment. In total, 362 participants (age (mean ± S.D.: 38.56 ± 13.14); sex (female-male: 73.76-26.24%)) responded to a web-based self-report questionnaire consisting of four sections: demographics, disease-related characteristics, and medical history questions. The final section consisted of a 23 item 5-point Likert-scale questionnaire related to long-term COVID-19 symptoms. After completing the questionnaire, subjects performed a VDT on a tablet screen to assess reaction times (RTs). An exploratory factorial analysis (EFA) was performed on the 23 long-COVID symptom questions, identifying 4 factors (cognition, behavior, physical condition, presence of anosmia and/or ageusia). The most important predictors of RTs were cognition and physical factors. By dissecting the cognitive and physical factors, learning, visual impairment, and headache were the top predictors of subjects' performance in the VDT. Long-COVID subjects showed higher RTs in the VDT after a considerable time post-disease, suggesting the presence of an attention deficit disorder. Attention impairment due to COVID-19 can be due to the presence of headaches, visual impairments, and the presence of cognitive problems related to the difficulty in learning new activities. The link between the slowing of reaction times and physical and cognitive symptoms post-COVID-19 suggests that attention deficit disorder is caused by a complex interaction between physical and cognitive symptoms. In addition, the study provides evidence that RTs in a VDT represent a reliable measure to detect the presence of long-COVID neurological sequelae.

A Latent Variable Analysis of Psychomotor and Neurocognitive Performance After Acute Cannabis Smoking.

This paper evaluated a novel, tablet-based neurocognitive and psychomotor test battery for detecting impairment from acute cannabis smoking using advanced quantitative methods. The study was conducted in a state with legal, recreational cannabis use and included participants who use cannabis occasionally or daily, and a no use comparison group. Participants completed a tablet-based test assessing reaction time, decision making, working memory and spatial-motor performance. The test was completed before and after participants smoked cannabis (or after a rest period in the case of controls). An Exploratory Factor Analysis approach was implemented to reduce dimensionality and evaluate correlations across the four assessed domains. Linear regression models were utilized to quantify associations between factor scores and cannabis use groups (daily vs. occasional vs. no use). Seven factors were identified explaining 56.7% of the variance among the 18 measures. Regression models of the change in factors after cannabis smoking indicated those who use cannabis daily demonstrated poorer performance on a latent factor termed Displaced and Delayed (standardized coefficient 0.567, 95% CI: 0.178, 0.955; P = 0.005) compared to those with no use. Those who use cannabis occasionally exhibited a decline in performance on a latent factor termed Recall and Reaction (standardized coefficient 0.714, 95% CI: 0.092, 1.336; P = 0.025) compared to no use. This analysis demonstrates an innovative, quantitative approach to study how cannabis consumption affects neurocognitive and psychomotor performance. Results demonstrated that acute cannabis use is associated with changes in neurocognitive and psychomotor performance, with differences based on the pattern of occasional or daily use.

Studies on the Actions of Calcium Channel Blockers, Anticholinesterases Agents on Experimentally Induced Spastic Paralysis in Normotensive Rats

Experimental paralysis was induced intramuscularly (i.m) in rats , using Suxa(1.08mg/kg ) , Deca (1.08mg/kg ) in normotensive rats weighing150-180g±2.5g (n=8).Various concentrations of these drugs ranging from (0.36—1.08mg/kg) were used , in order to assess at what concentrations will induced spastic paralysis sustained without death. Similarly, dose response concentrations effect was examined and the onset of action( ie time taken to observe paralysis and manifestation of pain and death was recorded. In some experiments, equimolar concentrations of Suxa(1.08mg/kg) and Deca(1.08mg/kg) was used to assess reaction time(RT) and potency of the agents. Thereafter the actions of Calcium Channel blockers (CCB), Diltiazem ( DTZ) and verapamil(VE) were studied in separate experiments. Anticholinesterase agent(AchE) in combination with Atropine a known antimuscarinic agent(AchE ) and investigated their actions on induced paralysis. The results obtained in these studies showed that CCB produced a significant potentiation of spastic paralysis on Suxa induced paralysis but non reversal effect with Deca , while AchE in combination ATR showed a reversal effect on paralysis induced by these agents in the concentrations used in his study. The aim of the study was to see interaction of these agents on sustained experimental paralysis in rodent.

0213 Circadian Entrainment and Cognition in College Students using Antidepressants

Abstract Introduction Depression, sleep disturbances, and cognitive deficits often co-occur. Compared to non-medicated controls, people using antidepressant medications (particularly serotonin agonists) often have improved sleep including increased slow wave sleep, quality and continuity. Improvements to cognition after antidepressant treatments are also common including benefits to reaction time, inhibition, and memory. Importantly, circadian deficits, including sleep onset latency, fragmentation, and phase shifts are common in patients with depression, yet the effect of antidepressant medication on circadian indicators is unclear. The current project examined sleep, circadian entrainment, and cognition in college students who were diagnosed with depression and using serotonin agonists and in those without depressive symptoms. Methods Participants completed cognitive tasks that assessed reaction time, memory, attention, inhibition, and logical reasoning via the Automated Neuropsychological Assessment Metric between 1100-1700 two times, first at study enrollment and second after a two-week study interval. After initial cognitive assessments, participants wore actigraphs for two weeks from which we extracted their sleep-wake patterns, total sleep time(TST), time in bed(TIB), sleep-onset latency(SOL), sleep efficiency, and wake after sleep onset(WASO). Study 1 included 15 undergraduate students (11F, 7 antidepressant users, Mage=19.53) and Study 2 included 25 graduate students (21F, 13 antidepressant users, Mage=25.37), all recruited from James Madison University. Results Study 1 found that undergraduate antidepressant users had longer TIB, TST, and SOL. No cognitive or entrainment differences were found between drug use conditions. Within the antidepressant group, higher dosage predicted shorter TIB(r2=.64, p&amp;lt;.05), poorer spatial processing speed(r2=.73, p&amp;lt;.05) and logical relation performance(r2=.81, p&amp;lt;.05). In study 2, no circadian or cognitive differences were present across drug conditions. Deficits in WASO and sleep efficiency for antidepressant users were present. Within the antidepressant group, years of antidepressant use and dosage predicted poorer reaction time(r2=.84, p&amp;lt;.05), inhibition(r2=.70, p&amp;lt;.05), and spatial processing(r2=.98, p&amp;lt;.05). Self-reported wake episodes also predicted poorer reaction time and inhibition. Years of antidepressant use, dosage, and time of antidepressant use predicted TIB(r2=.73, p&amp;lt;.05), and time of antidepressant use predicted TST(sr2=.79, p&amp;lt;.05). Conclusion Future studies should use longitudinal research designs and prospective methods to examine the impact of antidepressant medications on circadian rhythms, sleep and cognition. Support (If Any)

Diagnostic and Predictive Ability of Reaction Time Assessments for Adolescent Concussion

Background:Concussed individuals demonstrate significantly slower reaction time than that of healthy controls, particularly in the acute post-injury timeframe. In addition, post-injury reaction time may predict concussion recovery timing. Given that multiple measurement methods exist to assess reaction time post-injury, clinicians treating concussion may desire more information regarding the clinical utility of these methods.Purpose:To determine the clinical utility of two reaction time assessments and identify the ability of each to predict persistent post-concussion symptoms (PPCS), defined as symptoms lasting >28 days post-concussion.Methods:Concussed participants, within 14 days of injury, and healthy controls aged 12 to 18 years completed measures of clinical and smartphone-recorded reaction time. For clinical reaction time testing, participants completed 8 trials of a drop-stick protocol in which participants caught a weighted measuring stick dropped from a standard height between the thumb and palm of the dominant hand. Reaction time was calculated as the distance the stick fell before being caught. Three clinical reaction time outcomes were calculated: mean time, fastest trial, and coefficient of variance among all 8 trials.Smartphone reaction time was assessed through a smartphone application (Reaction Test Pro), which measured the speed at which patients responded to a simple on-screen stimulus. Participants were instructed to tap the phone as quickly as possible when an on-screen button changed color for 30 trials, an approximate test time of 2-3 minutes. Smartphone reaction time was output automatically by the application as the mean of all completed trials.Results:Concussion participants (n=54; 15.1±1.68 years of age; 50% female) assessed 7.0±3.05 days post-injury demonstrated worse performance than healthy controls (n=17; 16.3±1.13 years of age, 47% female) on all measures of reaction time (Table 1). Smartphone-recorded reaction time provided the largest mean difference between groups to distinguish concussed vs control participants. After controlling for age and concussion history, measures of mean clinical and smartphone reaction time were significant predictors of developing PPCS (Table 2).Conclusion:Smartphone-recorded reaction time within 2 weeks of concussion provide the greatest mean difference between concussed and control participants and predicted PPCS development in adolescents. Given the simplicity of smartphone-based measurements in comparison to other options for assessing reaction time, as well as the ubiquity and accessibility of smartphone technology, this technique may be preferred by physicians looking for direct measures of post-concussion reaction time. These assessments may also be used for early identification of patients at increased risk of developing PPCS.Table 1.Between-groups differences for reaction time and AUC values. Data represented as mean ± SD, or median [IQR].Table 2.Logistical regression predicting persistent post-concussion symptoms, controlling for age and concussion history.

Atypical Tactile Perception in Early Childhood Autism

We assessed different aspects of tactile perception in young children (3–6 years) with autism. Autistic and neurotypical children completed vibrotactile tasks assessing reaction time, amplitude discrimination (sequential and simultaneous) and temporal discrimination (temporal order judgment and duration discrimination). Autistic children had elevated and more variable reaction times, suggesting slower perceptual-motor processing speed and/or greater distractibility. Children with autism also showed higher amplitude discrimination and temporal order judgement thresholds compared to neurotypical children. Tactile perceptual metrics did not associate with social or tactile sensitivities measured by parent-reports. Altered tactile behavioral responses appear in early childhood, can be quantified but appear dissociated from sensitivity. This implies these measures are complementary, but not necessarily related, phenomena of atypical tactile perception in autism.

Accuracy of the SWAY Mobile Cognitive Assessment Application.

BackgroundMobile electronic devices have become integral tools in addressing the need for portable assessment of cognitive function following neurocognitive/motor injury. SWAY Medical, Inc., has employed mobile device motion-based technology in the SWAY Cognitive Assessment (SWAY CA) application to assess cognitive function.PurposeThe purpose of this study was to assess whether the SWAY CA application (reaction time, impulse control and inspective time) was able to reliably operate on different mobile devices and operating systems (iOS, Android). The study further sought to assess the validity of the SWAY CA application against the FDA approved ImPACT QT mobile device application.Study DesignOriginal Research, observational study of validity.Methods88 healthy, young adults, 18 to 48 years (mean= 22.09 ± sd=4.47 years) completed four, randomized and counter-balanced, reaction time tests (2- SWAY RT, 2- ImPACT QT) using different operating systems (iOS, Android) of 4 randomly assigned mobile devices.ResultsANOVAs reported the SWAY CA application (reaction time, impulse control, inspection time) operated reliably with iPhone 6S, Samsung Galaxy S9, and iPad Pro 5 mobile devices (p > 0.05), respectively. Google Pixel 3 reliability with SWAY CA application remains undetermined. SWAY CA simple reaction motion measures were in agreement (r = -0.46 to 0.22, p ≤ 0.05) with several ImPACT QT reaction time measures. SWAY CA impulse control and inspection time measures are weakly correlated (r = -0.25 to -0.46, p ≤ 0.05) with five ImPACT QT reaction time measures.ConclusionThe motion-based SWAY CA mobile device application appears to reliably operate when being administered on different mobile devices and software operating systems. Furthermore, the SWAY CA application appears to be comparable to the ImPACT QT and serve as a valid tool for assessing reaction time measures.Level of EvidenceLevel 2b (observational study of validity).

Age-related dissociation of N400 effect and lexical priming

The use of contextual information is an important capability to facilitate language comprehension. This can be shown by studying behavioral and neurophysiological measures of accelerated word recognition when semantically or phonemically related information is provided in advance, resulting in accompanying attenuation of the respective event-related potential, i.e. the N400 effect. Against the background of age-dependent changes in a broad variety of lexical capacities, we aimed to study whether word priming is accomplished differently in elderly compared to young persons. 19 young (29.9 ± 5.6 years) and 15 older (69.0 ± 7.2 years) healthy adults participated in a primed lexical decision task that required the classification of target stimuli (words or pseudo-words) following related or unrelated prime words. We assessed reaction time, task accuracy and N400 responses. Acceleration of word recognition by semantic and phonemic priming was significant in both groups, but resulted in overall larger priming effects in the older participants. Compared with young adults, the older participants were slower and less accurate in responding to unrelated word-pairs. The expected N400 effect was smaller in older than young adults, particularly during phonemic word and pseudo-word priming, with a rather similar N400 amplitude reduction by semantic relatedness. The observed pattern of results is consistent with preserved or even enhanced lexical context sensitivity in older compared to young adults. This, however, appears to involve compensatory cognitive strategies with higher lexical processing costs during phonological processing in particular, suggested by a reduced N400 effect in the elderly.

Open-source open-access reaction time test (OORTT): an easy tool to assess reaction times.

The speed of information processing is one of the most reliable indices of cognitive efficiency. The most common way to evaluate this ability is to assess reaction times (RTs). The technical limitations of previous tasks, aimed at measuring RT, have motivated us to develop a new battery for their evaluation. The aim of this study is to build an open-source, open-access reaction time test (OORTT), which has the following characteristics: rapid and easy administration, robust Italian normative data based on a wide age range, a simple scoring system, compatibility with all operating systems, no license or activation costs, and based on an open-source software platform. The battery is composed of three tasks: simple reaction times (SRT), Go/No-Go (GNG) condition, and four-position reaction times (4PRT). The battery was administered to 300 healthy participants aged between 14 and 89, and 3 groups of patients: 24 right brain-damaged; 21 left brain-damaged, and 19 degenerative cognitively impaired. We have developed specific norms for each task of the test battery: SRT, GNG, and 4PRT. Compared with healthy individuals, all groups obtained lower scores. More specifically, cognitively impaired patients obtained significantly longer RTs than healthy participants as well as unilateral brain-damaged patients. In the 4PRT task, right brain-damaged patients obtained a significantly left > right difference in RTs. In conclusion, the OORTT test battery proved to be a valuable tool which can be used in the clinical environment for cases of different attentional deficits after focal or degenerative brain damage.

Subjective Imaging Effect Assessment for Intelligent Imaging Terminal Design: a Method for Engineering Site

A kind of Subjective Imaging Effect Assessment (SIEA) method and its applications on intelligent imaging terminal design in engineering site are presented. First, some visual assessment indices are used to characterize the imaging effect: the image brightness, the image brightness uniformity, the color image contrast, the image edge blur, the image color difference, the image saturation, the image noise, and the integrated imaging effect index. A linear weighted function is employed to carry out the SIEA computation and the Analytic Hierarchy Process (AHP) technique is used to estimate its weights. Second, a SIEA software is developed. It can play images after the settings of assessment index or assessment reaction time, etc. Third, two cases are used to illustrate the application effects of proposed method: the image enhancement system design for surveillance camera and the imaging environment perception system design for intelligent lighting terminal. A Prior Sequential Stimulus (PSS) experiment is proposed to improve the evaluation stability of SIEA method. Many experiment results have shown the proposed method can realize a stable system design or parameters setting for the intelligent imaging terminal in engineering site.

Detection of Persisting Concussion Effects on Measures of Neuromechanical Responsiveness

Abstract INTRODUCTION Numerous investigations have documented elevated risk for musculoskeletal injury following sport-related concussion, which suggests that an unrecognized vulnerability persists beyond the resolution of symptoms and return to sport participation. Improved clinical testing methods are needed to better assess the interrelated neurocognitive and neuromuscular capabilities of athletes who may have elevated susceptibility to MSK injury, and possible risk for long- term alterations in brain function, despite resolution of overt concussion symptoms. The term “neuromechanics” refers to the study of interactions between neural, biomechanical, and environmental dynamics We use the term “neuromechanical responsiveness” (NMR) to designate the ability to optimally integrate neurocognitive and neuromuscular processes during participation in sport-related activities. NMR testing may play an critical role in optimizing safe return to play circumstances. METHODS A cohort of 48 elite athletes (34 males: 23.8 ± 4.4 yr; 14 females: 25.4 ± 4.5 yr) performed visuomotor reaction time (VMRT) tests involving rapid manual contact with illuminated target buttons that included 2 dual-task conditions: 1) simultaneous oral recitation of scrolling text (VMRT + ST) and 2) simultaneous verbal responses to identify the right or left direction indicated by the center arrow of the Eriksen flanker test (VMRT + FT). A whole-body reactive agility (WBRA) test requiring side-shuffle movements in response to visual targets was used to assess reaction time, speed, acceleration, and deceleration. RESULTS Concussion occurrence at 2.0 ± 2.3 yr prior to testing was reported by 21 athletes. Strong univariable associations were found for VMRT + FT left minus right difference = 15 ms (OR = 7.14), VMRT + ST outer 2-ring to inner 3-ring ratio = 1.28 (OR = 4.58), and WBRA speed asymmetry = 7.7% (OR = 4.67). A large VMRT + FT X VMRT + ST interaction effect was identified (OR = 25.00). Recursive partitioning identified a 3-way VMRT + FT X VMRT + ST X WBRA interaction that had 100% positive predictive value for identification of athletes with concussion history, whereas negative status on all 3 factors provided 90% negative predictive value. CONCLUSION Performance on dual-task VMRT tests and the WBRA test identified NMR deficiencies among elite athletes who reported a history of concussion.

Gender differences in the behavioral and subjective effects of methamphetamine in healthy humans

RationaleMethamphetamine (MA) use is steadily increasing and thus constitutes a major public health concern. Women seem to be particularly vulnerable to developing MA use disorder, as they initiate use at a younger age and transition more quickly to problematic use. Initial drug responses may predict subsequent use, but little information exists on potential gender differences in the acute effects of MA prior to dependence.ObjectiveWe examined gender differences in the acute effects of MA on subjective mood and reward-related behavior in healthy, non-dependent humans.MethodsMen (n = 44) and women (n = 29) completed 4 sessions in which they received placebo or MA under double-blind conditions twice each. During peak drug effect, participants completed the monetary incentive delay task to assess reaction times to cues signaling potential monetary losses or gains, in an effort to determine if MA would potentiate reward-motivated behavior. Cardiovascular and subjective drug effects were assessed throughout sessions.ResultsOverall, participants responded more quickly to cues predicting incentivized trials, particularly large-magnitude incentives, than to cues predicting no incentive. MA produced faster reaction times in women, but not in men. MA produced typical stimulant-like subjective and cardiovascular effects in all participants, but subjective ratings of vigor and (reduced) sedation were greater in women than in men.ConclusionsWomen appear to be more sensitive to the psychomotor-related behavioral and subjective effects of MA. These findings provide initial insight into gender differences in acute effects of MA that may contribute to gender differences in problematic MA use.