Simple Visual Reaction Time Research Articles

Effects of strenuous exercise on visual perception are independent of visual resolution

Strenuous exercise may have the detrimental effects on visual perception. However, it is unclear whether visual resolution is related to the detrimental effects on visual perception. The purpose of this study was to examine whether the effects of strenuous exercise on visual perception are dependent on visual resolution. Given that visual resolution decreases in the periphery of the visual field, we hypothesized that if visual resolution plays a role in the detrimental effects on visual perception, the detrimental effects may be exaggerated toward the periphery of the visual field. Simple visual reaction time was measured at rest and during cycling at 40% and 75% peak oxygen uptakes (VO2). Visual stimuli were randomly presented at 2°, 10°, 30°, and 50° to either the right or left of the midpoint between the eyes with equal probability. RT was fractionated into premotor and motor components (i.e. premotor time and motor time) based on electromyographic recording. The premotor time during exercise at 40% peak VO2 was not different from that at rest. In contrast, the premotor time during exercise at 75% peak VO2 was significantly longer than that at rest (p=0.018). The increase in the premotor time was observed irrespective of eccentricity, and the detrimental effects were not exaggerated toward the periphery of the visual field. The motor time was not affected by exercise. The current findings suggest that the detrimental effects of strenuous exercise on visual perception are independent of visual resolution.

Chronoscopic reading in whole body reaction times in detecting cognitive dysfunction in metabolic syndrome: A case control study

The metabolic syndrome, a clustering of several commonly occurring disorders that include abdominal obesity, hypertriglyceridemia, low high-density lipoprotein level, hypertension, and hyperglycemia, has been specifically investigated as a risk factor for cognitive decline in elderly individuals. The metabolic syndrome may be a risk factor for cognitive decline because it summarizes the joint effects of these risk factors. It is known that difference between simple and choice reaction time (RT) implies time required for cognition. Though delayed choice RTs indicate involvement of cognition, they cannot quantify how much time is required for cognition. In whole body simple reaction time (WBSRT), RT is split into two chronoscopic readings: C1 and C2. C1 measures time required for central processing which requires cognition and C2 measures total RT. C2-C1 measures time required for peripheral motor response. We hypothesized that whole body choice RT chronoscopic reading 1 (WBCRTC1) will be delayed in metabolic syndrome and WBCRTC1 will have predictive value in detecting cognitive dysfunction. Hospital-based cross-sectional case-control study. Study was conducted on 120 subjects using visual and WBSRT having criteria of age (40-60 years) and metabolic syndrome, compared with equal number of age- and sex-matched controls. Statistical analysis was done by independent t-test and duration of metabolic syndrome was correlated with cognition times (WBCRTC1) using Pearson's correlation. Predictive value of WBCRTC1 was calculated using receiver operating characteristic curve. Delayed visual simple RT, visual choice RT, WBSRT, and whole body choice RT (WBCRT) observed among subjects metabolic syndrome when compared with controls. Choice RTs were more delayed compared to simple RTs. WBCRTC1 (608.8 ± 132 ms) was more delayed than WBSRTC1 (424.05 ± 89.9 ms) among metabolic syndrome indicating cognitive dysfunction. Unfortunately, there was no significant correlation between duration of metabolic syndrome with cognition. The best cut-off value for WBCRTC1, when predicting cognitive dysfunction in metabolic syndrome was 542.5 ms (sensitivity 36.7% and specificity 31.6%). WBCRTC1 can be used as a tool to detect cognitive dysfunction.

Discriminating Drivers through Human Factor and Behavioral Difference

Since Greenwood and Woods' (1919) study in tendency of accident, many researchers have insisted that various human factors (sensation seeking, anger, anxiety) are highly correlated with reckless driving and traffic accidents. Oh and Lee (2011) designed the Driving Behavior Determinants Questionnaire, a psychological tool to predict danger level of drivers and discriminate them into three groups (normal, unintentionally reckless, and intentionally reckless) by their characteristics, attitude, and expected reckless behavior level. This tool's overall accuracy of discrimination was 70%. This study aimed to prove that the discrimination reflects the behavioral difference of drivers. Twenty-four young drivers were requested to react to the visual stimuli (tests for subjective speed sense, simple visual reaction time, and left turning at own risk). The results showed no differences in subjective speed sense among the driver groups, which means drivers' excessive speeding behaviors occur due to intention based on personality and attitude, not because of sensory disorders. In addition, there were no differences in simple reaction time among driver groups. However, the results of the ‘Left turning at drivers’ own risk task” revealed significant group differences. All reckless drivers showed a greater degree of dangerous left turning behaviors than the normal group did.

Effects of Vehicle Exhaust on Childrenʼs Neurobehavioral Functions Scored by Computerized Neurobehavioral Evaluation System

PP-31-062 Background/Aims: Effects of vehicle exhaust on children's neurobehavioral functions scored by Computerized Neurobehavioral Evaluation System. Methods: Three schools in Beijing which located in the areas with different levels of traffic pollution were chosen based on the counts of passed by automobiles and the monitoring data of ambient air pollution. The order of traffic pollution levels at school campus were A1 < A2 < A3. Neurobehavioral functions of children in grade 3 were measured through Computerized Neurobehavioral Evaluation System, which involved following test items: Visual Retention Test (VRT), Visual Simple Reaction time (include VSRT-Prh and VSRT-Nprh), Line Discrimination (LDT), Continuous Performance (CPT). Neurobehavioral ability indexes (NAI) were calculated by recommended equation. Results: Children's NAI of VRT were 0.74 ± 0.15 in School A1, 0.67 ± 0.20 in School A2, 0.70 ± 0.17 in School A3, respectively. ANOVA indicated significant differences among 3 schools (F = 4.158, P = 0.017). NAI of VSRT-Prh were 15.63 ± 6.81 in School A1, 14.50 ± 7.53 in School A2, 13.66 ± 6.67 in School A3, but no significant differences existed. NAI of VSRT-Nprh were 14.44 ± 8.13 in School A1, 14.21 ± 7.42 in School A2, 13.96 ± 7.15 in School A3, and no significant differences existed. NAI of LDT were 0.26 ± 0.10 in School A1, 0.30 ± 0.12 in School A2, and 0.30 ± 0.09 in School A3. ANOVA indicated significant differences among 3 schools (F = 3.577, P = 0.033). NAI of CPT were similar among 3 schools. Multiple regression showed that compared with School A1 children, School A2 had lower NAI in VRT, VSRT-Prh, and VSRT-Nprh, but higher NAI in LDT and CPT; and children in School A3 had significantly lower NAI in VRT and VSRT-Prh (P = 0.062 and 0.047) and significantly higher NAI of LDT (P = 0.026). There were no significant differences on NAI of VSRT-Nprh between School A1 and School A3. Conclusion: The study showed that there were correlative relationship between vehicle exhaust exposure and children's NAI of Computerized Neurobehavioral Evaluation System.

The Simplest Chronoscope II: Reaction Time Measured by Meterstick versus Machine

Visual simple reaction time (SRT) scores measured in 31 college students of both sexes by use of the simplest chronoscope methodology (meterstick SRT) were compared to scores obtained by use of an electromechanical multi-choice reaction timer (machine SRT). Four hypotheses were tested. Results indicated that the previous mean value of meterstick SRT was replicated; meterstick SRT was significantly faster than long-standing population estimates of mean SRT; and machine SRT was significantly slower than the same long-standing mean SRT estimates for the population. Also, the mean meterstick SRT of 181 msec. was significantly faster than the mean machine SRT of 294 msec. It was theorized that differential visual information processing occurred such that the dorsal visual stream subserved meterstick SRT; whereas the ventral visual stream subserved machine SRT.

Effect of acute exercise of differing intensities on simple and choice reaction and movement times

Objective The purpose of the present study was to examine the effect of acute, short-duration exercise on the performance of simple and choice visual reaction and movement times. Method Following an incremental test to exhaustion to determine exercise intensities, 12 male participants completed simple and choice reaction tests on a cycle ergometer where both reaction time and movement time were measured, with each test being performed on a separate day. Tests were performed at rest, moderate, heavy and severe intensities. Result For reaction time, a 2-way (reaction time complexity × exercise intensity) repeated measures Analysis of Variance demonstrated a significant interaction effect ( p = 0.02) and polynomial contrasts demonstrated a linear effect for choice reaction time ( p < 0.05) (where choice reaction time decreased with increasing exercise intensity), but no significant effect for simple reaction time. For movement time, polynomial contrasts for exercise intensity showed a significant quadratic effect ( p = 0.01) (with movement time fastest in the moderate to heavy domains). There was a significant main effect for complexity in both reaction ( p < 0.001) and movement ( p = 0.002) time. Conclusion The results of this study showed that simple and choice reaction times were affected differently by acute, short-duration exercise of differing intensities. The movement time data differ from previous research and show a quadratic effect rather than a linear one.

Simple reaction time: It is not what it used to be

This article calls attention to the large amount of evidence indicating that simple visual reaction time (RT) has increased. To show that RT has increased, the RTs obtained by young adults in 14 studies published from 1941 on were compared with the RTs obtained by young adults in a study conducted by Galton in the late 1800s. With one exception, the newer studies obtained RTs longer than those obtained by Galton. The possibility that these differences in results are due to faulty timing instruments is considered but deemed unlikely. Of several possible causes for longer RTs, two are regarded as tenable: that RT has been increased by the buildup of neurotoxins in the environment and by the increasing numbers of people in less than robust health who have survived into adulthood. The importance of standardizing tests of RT in order to enable more refined analyses of secular trends in RT is emphasized.

An ideal observer approach to simple visual reaction time

An ideal observer approach to simple visual reaction time

Energetic effects of stimulus intensity on prolonged simple reaction-time performance

The efficiency of cognition is modulated by energetic factors like effort, fatigue or circadian variation, which affect even the most basic cognitive operations. For instance, speeded detection in simple reaction-time (SRT) tasks usually slows down over time. The literature suggests that either mindlessness due to routinization or mental fatigue due to attentional resource depletion might underlie this decrement. We tested these assumptions in three 25-min visual SRT tasks using easy-to-detect high-intensity and hard-to-detect low-intensity stimuli presented in both blocked and mixed fashion. Mindlessness theory predicts that less monotonous stimulation (i.e. the mixed presentation) would mitigate the time-related decrement for high- and low-intensity stimuli alike, whereas resource-depletion theory predicts opposite effects of mixed presentation on high- versus low-intensity stimuli. Indeed, stimulus intensity and presentation mode cross-interacted significantly, indicating that the performance decline was steeper for high-intensity stimuli but less steep for low-intensity stimuli during mixed compared to blocked presentation, respectively. These results strongly suggest that the time-related efficiency decrement during prolonged SRT performance is related to accumulating mental fatigue. A conjecture is put forward that explains both resource depletion and mindlessness from the perspective of self-regulation. Our study underscores the need to incorporate energetic factors into models of cognition to facilitate their translation into real-world applications.

Comparison between Auditory and Visual Simple Reaction Times

Objective: The purpose of this study was to find out whether the simple reaction time was faster for auditory or visual stimulus and the factors responsible for improving the performance of the athlete. Methodology: 14 subjects were as- signed randomly into groups consisting of 2 members. Both the members from each group performed both the visual and auditory tests. The tests were taken from the DirectRT software program from a laptop. The DirectRT software consists of Testlabvisual and Testlabsounds to test the reaction times to visual and auditory stimuli. The 2 members from each group completed both the visual and auditory reaction times, the data was taken and the mean reaction time was calculated excluding the first and last values. Results: The results show that the mean visual reaction time is around 331 milliseconds as compared to the mean auditory reaction time of around 284 milliseconds. Conclusion: This shows that the auditory reaction time is faster than the visual reaction time. And also males have faster reaction times when compared to females for both auditory as well as visual stimuli.

Motor cortex excitability responses to a simple visual reaction time task

Motor cortex excitability responses to a simple visual reaction time task

Association of Traffic-Related Air Pollution with Children’s Neurobehavioral Functions in Quanzhou, China

ISEE-0914 Objectives: The objective of this study was to explore the association between traffic-related air pollution exposure and its impacts of children’s neurobehavioral functions. Methods: A field study was conducted in Quanzhou, China where two primary schools were chosen based on traffic density and monitoring data of ambient air pollutants. School A was located in polluted area and School B in clear area. Nitrogen dioxide (NO2) and PM10 at campus and classroom were monitored as the indicators for traffic-related air pollution. A battery of manual and computerized neurobehavioral testing was administered to evaluate children’s neurobehavioral functions. Results: Median concentrations of NO2 in School A and School B campuses were 0.036 mg/m3 and 0.007 mg/m3, respectively (P < 0.05). The multivariate linear regression analyses showed that after controlling the potential confounding factors, children living in polluted area showed poorer performance on all tests, and the differences between 6 of 9 tests (66.7%) achieved statistical significance. They were Visual Simple Reaction Time with preferred hand and non-preferred hand, Continuous Performance, Digit Symbol, Aim Tracing and Sign Register, respectively. Conclusion: Chronic low-level exposure to traffic-related air pollution may have a negative impact on children’s neurobehavioral functions. More studies are needed to explore the potentially neurotoxic effects of traffic exhausts.

Association of Traffic-Related Air Pollution with Children’s Neurobehavioral Functions in Quanzhou, China

BackgroundWith the increase of motor vehicles, ambient air pollution related to traffic exhaust has become an important environmental issue in China. Because of their fast growth and development, children are more susceptible to ambient air pollution exposure. Many chemicals from traffic exhaust, such as carbon monoxide, nitrogen dioxide, and lead, have been reported to show adverse effects on neurobehavioral functions. Several studies in China have suggested that traffic exhaust might affect neurobehavioral functions of adults who have occupational traffic exhaust exposure. However, few data have been reported on the effects on neurobehavioral function in children.ObjectivesThe objective of this study was to explore the association between traffic-related air pollution exposure and its effects on neurobehavioral function in children.MethodsThis field study was conducted in Quanzhou, China, where two primary schools were chosen based on traffic density and monitoring data of ambient air pollutants. School A was located in a clear area and school B in a polluted area. We monitored NO2 and particulate matter with aerodynamic diameter ≤ 10 μm as indicators for traffic-related air pollution on the campuses and in classrooms for 2 consecutive days in May 2005. The children from second grade (8–9 years of age) and third grade (9–10 years of age) of the two schools (n = 928) participated in a questionnaire survey and manual-assisted neurobehavioral testing. We selected 282 third-grade children (school A, 136; school B, 146) to participate in computer-assisted neurobehavioral testing. We conducted the fieldwork between May and June 2005. We used data from 861 participants (school A, 431; school B, 430) with manual neurobehavioral testing and from all participants with computerized testing for data analyses.ResultsMedia concentrations of NO2 in school A and school B campus were 7 μg/m3 and 36 μg/m3, respectively (p < 0.05). The ordinal logistic regression analyses showed that, after controlling the potential confounding factors, participants living in the polluted area showed poor performance on all testing; differences in results for six of nine tests (66.7%) achieved statistical significance: Visual Simple Reaction Time with preferred hand and with nonpreferred hand, Continuous Performance, Digit Symbol, Pursuit Aiming, and Sign Register.ConclusionWe found a significant relationship between chronic low-level traffic-related air pollution exposure and neurobehavioral function in exposed children. More studies are needed to explore the effects of traffic exhaust on neurobehavioral function and development.

Effects of Alzheimer's disease and mild cognitive impairment on driving ability: a controlled clinical study by simulated driving test

To assess the effects of Alzheimer's disease (AD) and Mild Cognitive Impairment (MCI) on simulated car driving ability. Twenty patients with a probable AD of mild severity (Clinical Dementia Rating, CDR = 1) were compared with 20 subjects with MCI (CD = 0.5), and a group of age-matched neurologically normal controls on a driving simulation task. Measures of driving competence included the length of run, the number of infractions (omission of stop at pedestrian crossings, speed limits violation), the number of stops at traffic lights, the mean time to collision, and the number of off-road events. Results in the driving competence measures were correlated with scores obtained from simple visual reaction times and mini-mental state examination (MMSE). The patients with mild AD performed significantly worse than MCI subjects and controls on three simulated driving measures, length of run and mean time to collision (p < 0.001), and number of off-road events (p < 0.01). MCI subjects had only a significantly shorter time-to-collision than healthy controls (p < 0.001). Simple visual reaction times were significantly longer (p < 0.001) in patients with AD, compared to MCI and healthy controls, and showed a borderline significant relation (p = 0.05) with simulated driving scores. Driving performance in the three groups did not significantly correlate with MMSE score as measure of overall cognitive function. Mild AD significantly impaired simulated driving fitness, while MCI limitedly affected driving performance. Unsafe driving behaviour in AD patients was not predicted by MMSE scores.

Differential redundancy gain in onset detection versus offset detection

In a visual simple reaction time paradigm with attention divided between the left and right visual fields, redundancy gain refers to the finding of faster responses to stimuli presented in both fields than to single stimuli. The present study investigated whether the effects of low-level perceptual processing affect the redundancy gain by comparing the detection of onsets versus offsets. In different blocks, participants responded to left and right visual field stimuli that either appeared (onset) or disappeared (offset), with a single stimulus change in some trials and two redundant stimulus changes in others. With onset stimuli, the results replicated previous redundancy gain effects. In contrast, there was much less redundancy gain when participants responded to stimulus offsets. This finding suggests that redundancy gain is sensitive to low-level perceptual characteristics, such as onset versus offset presentation of stimuli.

Effects of a Moderate Evening Alcohol Dose. II: Performance

This second of a pair of papers investigates the effects of a moderate dose of alcohol and staying up late on driving simulation performance and simple visual reaction time (RT) at a known circadian phase in well-rested young adults. Twenty-nine adults (9 males), ages 21 to 25 years, spent 1 week on an at-home stabilization schedule of 8.5 to 9 hours, followed by 3 nonconsecutive nights in-lab: adaptation, placebo, and alcohol. Performance task practice occurred on 3 occasions before the study. Alcohol (vodka; 0.54 g/kg men; 0.49 g/kg women mixed with tonic) was consumed over 30 minutes ending 1 hour before normal bedtime; the same quantity of beverage was given on placebo. Driving simulation (with drive-only and dual-task drive and subtract components) and psychomotor vigilance task (PVT) testing occurred before and after alcohol/placebo ingestion. Breath alcohol concentration (BrAC) readings were taken before all test sessions. Saliva samples were taken approximately every 30 minutes to determine circadian phase. Driving simulation and PVT variables significantly deteriorated with increasing time awake. Driving simulator lane variability was worse with alcohol compared with placebo at 15.5 hours awake. No PVT variable showed an effect of alcohol. Driving simulation performance deteriorated with extended waking and with alcohol; driving was most impaired at the peak alcohol level. The PVT, less complex than the driving simulation, did not show effects of alcohol, a finding consistent with previous literature that disruptive effects of low alcohol concentrations increase with task complexity. Overall, simulated driving performance is significantly impaired late at night when even a moderate dose of alcohol is consumed.

Cognitive processing of visual stimuli in patients with organophosphate insecticide poisoning

To determine the effect of organophosphate (OP) insecticide poisoning on cognitive processing time of visual stimuli. We compared 33 patients who recovered from the cholinergic phase (on average, 15 days after poisoning) with an age- and sex-matched control group. The tests used were simple visual reaction time (SVRT), recognition visual reaction time (RVRT), visual evoked potentials (VEP), and motor evoked potentials (MEP). The term cognitive processing time (CPT) was used to denote the time taken from the initial cortical perception of a stimulus to initiation of the descending motor impulse. CPT of each type of visual reaction was calculated by subtracting the sum of the visual impulse duration and the motor impulse duration from reaction time (CPT = reaction time-[P100 latency + total motor conduction time]). Both the SVRT and RVRT were significantly prolonged in patients. There was no significant difference in P100 latency or total motor conduction time (TMCT) between patients and the controls. However, CPT of simple visual reactions (CPT(SVR)) and the CPT of recognition visual reactions (CPT(RVR)) were significantly prolonged in patients. Acute organophosphate poisoning may slow higher-order cognitive processing involved in visual stimulus detection and visual stimulus discrimination, even after clinical recovery from the cholinergic phase.

Perceptual Visual Skills in Young Highly Skilled Basketball Players

A simple method was designed to evaluate visual abilities such as disance visual acuity, binocular horizontal visual field, simple and choice visual reaction times, and stereoscopic vision in skilled 11- to 13-yr.-old basketball players participating in a 15-day summer training camp. On a test battery, visual abilities were monitored in 473 players of the Spanish Basketball Federation over a 5-yr. period. The players showed outstanding scores on distance visual acuity and stereoscopic vision, and good visual reaction times and horizontal visual fields. When scores were compared by sex and age, significant differences on certain visual measures were observed. Many layers showed crossed eye-hand dominance. Visual screening programs may help promote visual health among junior basketball players and could be used for performance training.

Lateralized readiness potential elicited by undetected visual stimuli

Visual stimuli undetected by normal subjects as a result of masking procedures can nonetheless activate response preparation in motor areas and yield a motor response. An unanswered question is whether the same holds for undetected subliminal stimuli that are not responded to. To answer this question, in this study normal subjects were tested on a simple visual reaction time task with stimuli above, at, or below the psychophysical threshold while the lateralized readiness potential (LRP), i.e. an electrophysiological correlate of premotor activation in the primary motor cortex, was computed. We found a reliable LRP not only for suprathreshold stimuli but also for subthreshold stimuli to which subjects did not respond. The main thrust of this study is that it provides evidence that activation of the motor cortex occurs even with subthreshold visual stimuli and without an overt response.

Attending visual and auditory signals: Ergonomics recommendations with consideration of signal modality and spatial stimulus–response (S–R) compatibility

This study investigated spatial stimulus–response (S–R) compatibility effects in a combined auditory–visual setting, in which subjects had to respond to a single signal that could be visual or auditory. Auditory signals were positioned either to the left or right of the subject on a transverse axis, and visual signals were positioned at two vertical locations in front of the subject on a longitudinal axis. There were three main findings. First, a strong spatial S–R compatibility effect was observed for both signal modalities and such correspondence of S–R positions elicited relatively faster responses. However, in a condition when either the visual or the auditory pairing was incompatible, reaction times increased dramatically. Second, responses made to the visual signals were generally faster than those to the auditory signals. This contradicted the previous finding that simple visual reaction time was longer than simple auditory reaction time. Thus, simple reaction times cannot be applied directly for the estimation of response speeds of different signal modalities in a multi-sensory control console. Third, a superior visual strength effect was observed in this choice reaction task. This visual strength effect was more marked in the conditions with conflicting S–R mapping pairings. Relevance to industry This study showed that spatial S–R compatibility and signal modality are two important interface design factors for enhancing response efficiency of operators in a multi-sensory control console. Some ergonomics recommendations based on these findings are given with the aim of improving interface design in multi-sensory control consoles in order to enhance the operators’ response speed and accuracy and overall system performance.