scholarly journals Independent reaction times method in Geant4‐DNA: Implementation and performance

2020 ◽  
Vol 47 (11) ◽  
pp. 5919-5930 ◽  
Author(s):  
José Ramos‐Méndez ◽  
Wook‐Geun Shin ◽  
Mathieu Karamitros ◽  
Jorge Domínguez‐Kondo ◽  
Ngoc Hoang Tran ◽  
...  
Keyword(s):  
Reaction Times ◽  
And Performance ◽  
Independent Reaction

scholarly journals Expectancy of Stress-Reducing Aromatherapy Effect and Performance on a Stress-Sensitive Cognitive Task

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Irina Chamine ◽  
Barry S. Oken
Keyword(s):  
Task Performance ◽  
Stress Reduction ◽  
Cognitive Task ◽  
Reaction Times ◽  
Event Related Potentials ◽  
Specific Effects ◽  
N200 Amplitude ◽  
Related Potentials ◽  
And Performance

Objective. Stress-reducing therapies help maintain cognitive performance during stress. Aromatherapy is popular for stress reduction, but its effectiveness and mechanism are unclear. This study examined stress-reducing effects of aromatherapy on cognitive function using the go/no-go (GNG) task performance and event related potentials (ERP) components sensitive to stress. The study also assessed the importance of expectancy in aromatherapy actions.Methods. 81 adults were randomized to 3 aroma groups (active experimental, detectable, and undetectable placebo) and 2 prime subgroups (prime suggesting stress-reducing aroma effects or no-prime). GNG performance, ERPs, subjective expected aroma effects, and stress ratings were assessed at baseline and poststress.Results. No specific aroma effects on stress or cognition were observed. However, regardless of experienced aroma, people receiving a prime displayed faster poststress median reaction times than those receiving no prime. A significant interaction for N200 amplitude indicated divergent ERP patterns between baseline and poststress for go and no-go stimuli depending on the prime subgroup. Furthermore, trends for beneficial prime effects were shown on poststress no-go N200/P300 latencies and N200 amplitude.Conclusion. While there were no aroma-specific effects on stress or cognition, these results highlight the role of expectancy for poststress response inhibition and attention.

EFFECT OF REACTION TRAINING ON DURATION AND REACTION TIMES

2021 ◽  
Vol 7 (27) ◽  
pp. 86-92
Author(s):  
Tülin ATAN
Keyword(s):  
Reaction Time ◽  
Normal Distribution ◽  
Training Program ◽  
Reaction Times ◽  
Rank Test ◽  
Tennis Players ◽  
Before And After ◽  
Speed Performance ◽  
And Performance ◽  
Training Exercises

In this study, it was aimed to examine the effects of reaction training on reaction time and speed in tennis players. For this purpose a total of 18 tennis players; 9 male (age; 13.33 ± 1.80 years) and 7 female (13.85 ± 2.19 years) were voluntarily participated the study. In this study, the reaction training program, which was applied for 2 days a week for 12 weeks, was prepared in addition to tennis training. In the reaction training, exercises suitable for visual and auditory reaction were used. Before and after the 12-week reaction training, a 30 m speed running test and reaction time tests were performed. Whether the data showed normal distribution was analyzed with the Shapiro Wilk test and it was determined that the data did not show normal distribution. Mann Whitney U test was used in comparisons between the two groups. Wilcoxan Signd Rank test was used in the comparisons made before and after the training. As a result of the statistical analysis, it was seen that both the physical characteristics and performance parameters of males and females in our study group were not statistically different (p>0.05). For this reason, all subjects were taken into consideration regardless of gender in comparisons before and after tennis training. After the reaction training program applied to the subjects, it was determined that the 30 m speed performance values were shortened in duration compared to the pre-training period, that is, the speed improved (p <0.01). When the reaction time values were compared before and after the training program applied, it was seen that the reaction time values improved significantly after the training (p <0.01). As a result, reaction training performed in tennis players’ increases speed and reaction time performance. Reaction training is recommended in sports branches where this type of motor is important.

Driver Vigilance in Automated Vehicles: Hazard Detection Failures Are a Matter of Time

2018 ◽  
Vol 60 (4) ◽  
pp. 465-476 ◽  
Author(s):  
Eric T. Greenlee ◽  
Patricia R. DeLucia ◽  
David C. Newton
Keyword(s):  
Safety Concern ◽  
Reaction Times ◽  
Vigilance Task ◽  
Time On Task ◽  
Vigilance Decrement ◽  
Automated Vehicles ◽  
Automated Driving ◽  
Automated Vehicle ◽  
Hazard Detection ◽  
And Performance

Objective: The primary aim of the current study was to determine whether monitoring the roadway for hazards during automated driving results in a vigilance decrement. Background: Although automated vehicles are relatively novel, the nature of human-automation interaction within them has the classic hallmarks of a vigilance task. Drivers must maintain attention for prolonged periods of time to detect and respond to rare and unpredictable events, for example, roadway hazards that automation may be ill equipped to detect. Given the similarity with traditional vigilance tasks, we predicted that drivers of a simulated automated vehicle would demonstrate a vigilance decrement in hazard detection performance. Method: Participants “drove” a simulated automated vehicle for 40 minutes. During that time, their task was to monitor the roadway for roadway hazards. Results: As predicted, hazard detection rate declined precipitously, and reaction times slowed as the drive progressed. Further, subjective ratings of workload and task-related stress indicated that sustained monitoring is demanding and distressing and it is a challenge to maintain task engagement. Conclusion: Monitoring the roadway for potential hazards during automated driving results in workload, stress, and performance decrements similar to those observed in traditional vigilance tasks. Application: To the degree that vigilance is required of automated vehicle drivers, performance errors and associated safety risks are likely to occur as a function of time on task. Vigilance should be a focal safety concern in the development of vehicle automation.

scholarly journals Relationship between alertness, performance, and body temperature in humans

2002 ◽  
Vol 283 (6) ◽  
pp. R1370-R1377 ◽  
Author(s):  
Kenneth P. Wright ◽  
Joseph T. Hull ◽  
Charles A. Czeisler
Keyword(s):  
Body Temperature ◽  
Human Performance ◽  
Reaction Times ◽  
Biological Time ◽  
Circadian Phase ◽  
Neurobehavioral Function ◽  
Improved Performance ◽  
And Performance ◽  
Subjective Alertness ◽  
The Relationship

Body temperature has been reported to influence human performance. Performance is reported to be better when body temperature is high/near its circadian peak and worse when body temperature is low/near its circadian minimum. We assessed whether this relationship between performance and body temperature reflects the regulation of both the internal biological timekeeping system and/or the influence of body temperature on performance independent of circadian phase. Fourteen subjects participated in a forced desynchrony protocol allowing assessment of the relationship between body temperature and performance while controlling for circadian phase and hours awake. Most neurobehavioral measures varied as a function of internal biological time and duration of wakefulness. A number of performance measures were better when body temperature was elevated, including working memory, subjective alertness, visual attention, and the slowest 10% of reaction times. These findings demonstrate that an increased body temperature, associated with and independent of internal biological time, is correlated with improved performance and alertness. These results support the hypothesis that body temperature modulates neurobehavioral function in humans.

Simple reaction times and performance in the detection of visual stimuli of patients with diabetes

2010 ◽  
Vol 40 (6) ◽  
pp. 591-596 ◽  
Author(s):  
Francisco J. Sanchez-Marin ◽  
Jose A. Padilla-Medina
Keyword(s):  
Visual Stimuli ◽  
Reaction Times ◽  
Simple Reaction ◽  
Patients With Diabetes ◽  
And Performance

MECHANICAL PERFORMANCE OF NOVEL POLYISOBUTYLENE-BASED ELASTOMERIC POLYURETHANES BEFORE AND AFTER HYDROLYSIS

2019 ◽  
Vol 92 (3) ◽  
pp. 481-495 ◽  
Author(s):  
Jozsef Kantor ◽  
Elizabeth A. Collister ◽  
Judit E. Puskas ◽  
Michael P. Mallamaci ◽  
Val C. Comes
Keyword(s):  
Mechanical Performance ◽  
Hydrolytic Stability ◽  
Reaction Times ◽  
High Viscosity ◽  
Stability Testing ◽  
Synthesis Conditions ◽  
Before And After ◽  
Hard Segments ◽  
And Performance ◽  
American Society

ABSTRACT The mechanical performance of thermoplastic elastomeric polyurethanes (PUs) before and after hydrolysis is investigated. These new PUs were prepared with a new asymmetric polyisobutylene-diol (PIB-diol), without the use of solvents, and with short reaction times. The PUs were made with dicyclohexylmethane 4,4′-diisocyanate and 1,4-butanediol in the hard segments and poly(hexamethylene carbonate) (PC)-diol and polyisobutylene (PIB)-diol in the soft segments. The functionality of PIB-diol was verified by mass spectrometry. Optimum solventless synthesis conditions and performance were found with a mixture of 50/50 PIB-diol/PC-diol (28.9 wt% PIB in the PU). This PU had 26.03 ± 1.19 MPa tensile strength with 286.92 ± 12.17% elongation before and 16.22 ± 0.65 with 301.17 ± 15.08% elongation after American Society for Testing and Materials (ASTM) hydrolytic stability testing. Importantly, after the hydrolytic stability testing, the stress–strain plot of this PIB–PU was similar to that of the control PC–PU. The PU with 70/30 PIB-diol/PC-diol (41.2 wt% PIB in the PU) performed slightly better but needed solvent during synthesis because of the high viscosity of the mixtures.

Laterality frequency, team familiarity, and game experience affect kicking-foot identification in Australian football players

2017 ◽  
Vol 12 (3) ◽  
pp. 351-358
Author(s):  
Benjamin B Moore ◽  
Roger D Adams ◽  
Nicholas J O’Dwyer ◽  
Kylie A Steel ◽  
Stephen Cobley
Keyword(s):  
Repeated Measures ◽  
Reaction Times ◽  
Football Players ◽  
Discrimination Capability ◽  
Capability Indices ◽  
Australian Football ◽  
Static Images ◽  
Player Game ◽  
And Performance ◽  
Team Familiarity

This study examined whether laterality frequency, team familiarity, and game experience affected preferred kicking foot identification in professional Australian Football players. Using a repeated-measures experimental design, 13 and 10 players, respectively, identified the kicking foot of 30 teammates and 30 opponents using static images in a randomised sequence. Accuracy (%), reaction time (RT ms), and discrimination capability indices were examined. Overall, participants were less accurate and had slower reaction times when identifying the kicking foot of opposing team players relative to the speed and accuracy of identifying teammates. Significantly lower discrimination accuracy was also evident in participants’ capability to identify left-footed players from two different opposing teams. In moderating trends, opposing player game experience was correlated with accuracy and reduced reaction times, while participant game experience correlated with faster reaction times only. Laterality, (opposing) team familiarity, and game experience affect kicking foot identification in Australian Football with training and performance implications.

Discrimination of Optic Flow Components: Access to the Third Dimension?

Perception ◽  
1996 ◽  
Vol 25 (1_suppl) ◽  
pp. 50-50
Author(s):  
T C A Freeman ◽  
T S Meese ◽  
M G Harris
Keyword(s):  
Optic Flow ◽  
Opposite Sign ◽  
Reaction Times ◽  
Vertical Shear ◽  
Horizontal Shear ◽  
Surface Slant ◽  
Flow Components ◽  
And Performance ◽  
Third Dimension ◽  
Speed Gradient

A growing body of evidence suggests that optic flow is processed by specialised 2-D motion mechanisms. We asked whether the visual system has parallel, or rapid serial, access to representations of optic flow components in a spatial 4AFC task. Random-dot kinematograms (144 dots per interval) depicting expansion, rotation, deformation (horizontal shear+vertical shear) or one of these components summed with translation, were presented in four spatially abutting circular windows (2.65 deg in diameter), and were temporally modulated by half a cycle of a 300 ms cosine-wave. Within a session, stimuli were of the same type, but the target had opposite sign and was selected with a mouse and cursor with feedback. Systematic local cues were removed by randomising (i) the orientation of the windowing configuration, and (ii) the dot speeds between intervals (speed gradient varied between 2.4% and 6%; translation varied between 16 and 40 min arc s−1). Preliminary results (average SE=3.4%) showed that in the absence of translation, performance was close to chance (25% correct) for rotation (23% correct) and deformation (27% correct), but was good for expansion (61% correct). The addition of translation had no effect on rotation but improved deformation (58% correct) and impaired expansion (22% correct). In experiment 2, unlimited stimulus repetitions were allowed and performance improved (>93%) for all conditions, though, as predicted from experiment 1, reaction times were fastest for expansion and deformation-plus-translation. Importantly, only these two conditions produced unambiguous 3-D perceptions of the stimuli, suggesting that surface slant and motion in depth are coded by mechanisms more rapidly accessible than those subserving general extraction of 2-D motion.

Impact of Quality of the Image, Orientation, and Similarity of the Stimuli on Visual Search for Faces

Perception ◽  
1994 ◽  
Vol 23 (1) ◽  
pp. 95-122 ◽  
Author(s):  
Sally M Kuehn ◽  
Pierre Jolicoeur
Keyword(s):  
Visual Search ◽  
Interactive Effect ◽  
Reaction Times ◽  
Spatial Relations ◽  
Distractor Type ◽  
Face Representation ◽  
The Face ◽  
And Performance ◽  
The Impact

Evidence from a series of visual-search experiments suggests that detecting an upright face amidst face-like distractors elicits a pattern of reaction times that is consistent with serial search. In four experiments the impact of orientation, number of stimuli in the display, and similarity of stimuli on search rates was examined. All displays were homogeneous. Trials were blocked by distractor type for three experiments. In the first experiment search rates for faces amidst identical faces rotated by 180° were examined. No advantage was evidenced in searching for an upright face. The impact of the quality of the face representation was examined in the second experiment. Search rates are reported for a line-drawn and a digitized image of a face amidst identical faces rotated by 180°. Search was faster for digitized than for line-drawn faces. The findings of the first experiment for orientation were replicated. In the third and fourth experiments the impact of disrupting the facial configuration in distractors was examined and performance was contrasted for blocked and mixed trials, respectively, with the same stimulus set. Reaction times increased with the number of distractors in the display in all but the nonface condition, which produced a shallow slope suggestive of parallel search. Search amidst other distractors appeared to involve the conjoining of a specific set of features with specific spatial relations. The hierarchy of relevant configural dimensions was inconsistent across these two experiments, suggesting that the symmetry, top-down order of features, orientation of the face, and predictability of the distractor type may have an interactive effect on search strategies.

Partial Response Activation to Masked Primes is Not Dependent on Response Readiness

2001 ◽  
Vol 92 (1) ◽  
pp. 208-222 ◽  
Author(s):  
Friederike Schlaghecken ◽  
Martin Eimer
Keyword(s):  
Relative Frequency ◽  
Time Course ◽  
Reaction Times ◽  
Reaction Time Task ◽  
Masked Priming ◽  
Overt Response ◽  
General Ability ◽  
Response Readiness ◽  
And Performance ◽  
Alternative Choice

Masked primes presented foveally prior to a target trigger an initial partial activation of their corresponding response, followed by an inhibition of the same response. The latter phase results in performance costs on compatible trials and performance benefits on incompatible trials relative to neutral trials (negative compatibility effect). The present study investigated whether this activation-follow-by-inhibition process depends on the overall or specific state of response readiness. In two masked priming experiments, response readiness was manipulated by varying the relative frequency of Go-trials in a Go/NoGo task (Exp. 1) and the relative frequency of left- and right-hand responses in a 2-alternative choice reaction time task (Exp. 2). In both experiments, mean reaction times were longer for infrequent responses than for frequent responses. However, negative compatibility effects were not affected by response frequency. This result indicates that neither the general ability of masked primes to elicit a partial motor activation nor the specific time course of this process is dependent on response readiness. It is concluded that response readiness affects the execution of an overt response rather than the initial activation of this response.

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