Effects of Local Muscular Fatigue Due to Isotonic and Isometric Exercise Upon Fractionated Reaction Time Components

Fractionated RT for a right knee-extension task was assessed on eight male and eight female Ss over eight treatment days. Following four consecutive days of 75 RT trials /day to insure stabilized strength and RT components, Ss were administered two days of bench stepping and two days of isometric exercise designed to induce muscular fatigue of the knee extensors. Significant strength decrements of up to 24% were induced by both the isotonic (bench stepping) and isometric exercise treatment conditions but no changes were observed in fractionated RT components. The results would seem to indicate that performance differences in fine-versus gross-motor skill tasks due to fatigue need to be more carefully examined.     

Hemispace Asymmetries and Laterality Effects in Arm Positioning

Hemispace asymmetries and laterality effects were examined on an arm positioning reproduction task. Sixteen male subjects were asked to reproduce both abductive and adductive positioning movements with the left or right arm within either the left or the right hemispace. Hemispace was manipulated using a 90 degrees head-rotation paradigm. A left hemispace advantage in positioning accuracy was predicted for both left and right arm movements on the grounds that the perceptual-motor control of positioning movements made in left hemispace is primarily mediated by the right hemisphere which is known to be advantageous for tasks which are spatial in nature (Heilman, Bowers, & Watson, 1984). No arm laterality effects were predicted to occur because the proximal musculature involved in the control of arm movements is innervated from both contralateral and ipsilateral cerebral hemispheres (Brinkman & Kuypers, 1973). Results showed that the predicted left hemispace advantage was evident for the right arm on the positioning variability measure alone, whereas it was absent for all other possible conditions on all error measures. Laterality (arm) effects were absent as predicted. The experiment also demonstrated a greater degradation of reproduction performance under the ′crossed" arm-hemispace conditions than under the ′uncrossed" conditions. A plausible explanation for the uncrossed advantage for the task is that under normal conditions, a single hemisphere is primarily responsible for both controlling the contralateral arm and directing attention to the contralateral hemispace, and consequently potential interhemispheric interference is minimized. A clear response bias effect in movement reproduction was also evident as a function of the direction of concurrent arm movement and head rotation. Arm movements made in the same direction as head rotation were systematically undershot in reproduction to a much greater degree than arm movements made in the opposite direction to head rotation.     

Effects of Expectancy and Attention in Vibrotactile Choice Reaction Time Tasks

The orienting of attention in space has not been considered in the tactile domain. This issue is examined using a modified version of a visual paradigm initially adopted by Posner, Snyder, and Davidson (1980), which manipulates the probability of a stimulus occurring at different spatial locations. Slower RTs at an unexpected stimulus location are thought to reflect the time required to shift attention from the expected to the unexpected location. In two experiments involving vibrotactile choice RT between left and right hands, the two hands were either crossed or uncrossed, and the hands were held both on the left side of the body, both on the right, or one on either side of the midline. There was no evidence to suggest that spatial location (left or right) affected the orienting of attention in the tactual modality. As predicted, RTs were slower when the arms were crossed compared with uncrossed, though this effect was smaller for the expected trials. A coding conflict hypothesis may explain both these findings, but the smaller effect in the expected trials may also reflect attentional factors. Both the relative and absolute location of the hands affected the magnitude of the crossed-arm effect and indicated that attention may play a role in the perceptual division of space into left and right sides. Possible reasons for hand or hemispace asymmetries in different simple and choice RT paradigms were discussed.     

Perceptual Anticipation and Reaction Time

To determine the effect of perceptual anticipation upon reaction time, two different types of experiment were carried out. In the first a skilled response had occasionally to be altered at a given point after a variable warning period. In the second the subject had to react to two auditory signals separated by a short time interval which was systematically varied, the second signal being expected or unexpected.

It was found that lack of readiness to respond to a signal, as revealed by a lengthened reaction time, may be due either to the subject not having prepared himself, as he was not expecting the signal; or to the subject not being able to prepare himself in time. Preparation for reacting to the second of the two signals, when both are expected and have to be reacted to, never appears to take more than between 0·2 and 0·4 seconds, as judged by reaction time. On the majority of occasions it appears to be complete in 0·2 seconds. These times are shorter than those usually given, because the extra delay due to incorrect anticipation has been excluded. With intervals of 0·1 seconds or less, delay in the second reaction may be due to the mechanical difficulty of responding quickly enough, especially when the two reactions have to be made in opposite directions.

The finding that lack of readiness might be due to the subject not expecting the signal, and the further finding that preparation took longer when a skilled response had to be extended than when it had to be stopped, both suggest that so-called Psychological refractoriness is due to lack of fore period in which to prepare for the response, rather than to a “Psychological refractory phase” comparable to the refractory phase of nerves. If, by dividing his attention, the subject was able to prepare for his next response while making his previous one, so-called Psychological refractoriness could be completely absent.     

脑功能一侧化加工中的元控制研究

1　引言　　有关大脑功能一侧化问题 ,本世纪 60年代前后的研究显示左右脑功能在言语和非言语方面有差异 ,70年代中期发现左右脑对外部信息的加工有分析与综合方式的差异 ,80年代中后期又发现左右脑对信息的表征特性也有一侧化现象 ,即左脑适合处理高频视觉空间刺激 ,而右脑适合处理低频视觉空间刺激。显然 ,以上研究采用的是二分法原则在不同的范畴内查寻左右脑功能活动以及加工特性的差异。值得重视的是 ,近期的不少研究提示不应过高估计这种功能差异。即使它们存在 ,对于正常人而言它也只能在左右脑正常功能关系状态下起作用。因此 ,有关…     

视觉监控作业中信号间隔时间和双任务对信号觉察的影响

本研究运用模拟实验,考察了以仪表显示为主的监控系统中信号间隔时间和双作业任务对人觉察信号的反应时间的影响.双作业中的主任务是要求被试同时监视4个仪表,次任务为对显示屏上一个红色亮点是否出现闪烁作简单的辨别反应.实验结果表明信号间隔时间是影响信号觉察反应时的一个重要因素.随着信号间隔时间由30-50秒延长到8-10分钟,信号觉察反应时随之先快后慢地增加.在低负荷的仪表监视作业中,通过增加一个刺激率较高而又比较简单的次任务,可使被试保持较高的唤醒水平和更好地集中注意,从而有利于提高信号觉察效率.     

Verbal and Affective Laterality Effects in P-Dyslexic,L-Dyslexic and Normal Children

Lateralization of verbal and affective processes was investigated in P-dyslexic, L-dyslexic and normal children with the aid of a dichotic listening task. The children were asked to detect either the presence of a specific target word or of words spoken in a specific emotional tone of voice. The number of correct responses and reaction time were recorded. For monitoring words, an overall right ear advantage was obtained. However, further tests showed no significant ear advantage for P-types, and a right ear advantage for L-types and controls. For emotions, an overall left ear advantage was obtained that was less robust than the word-effect. The results of the word task are in support of previous findings concerning differences between P- and L-dyslexics in verbal processing according to the balance model of dyslexia. However, dyslexic children do not differ from controls on processing of emotional prosody although certain task variables may have affected this result.     

The Effects of Force and Direction Uncertainty on Choice Reaction Time in an Isometric Force Production Task

The two experiments reported examined the temporal organization of force and direction motor-programming processes in a step-input tracking type task. Both experiments observed a reduction in reaction time in the direction-uncertain conditions compared to the direction-certain ones. Thus it seems as though the direction decision does not have to precede the selection of the proper amount of force. Experiment 2 observed an underadditive interaction between levels of direction uncertainty (certain or uncertain) and levels of force uncertainty (certain or uncertain). This interaction was interpreted as support for a parallel organization of the processes responsible for the programming of force and direction and thus, strongly supports the parallel model of programming recently proposed by Klapp (1977a, b).     

化疗后不同时间有氧运动对乳腺癌癌因性疲乏的影响

探讨化疗后不同时间运动干预对乳腺癌癌因性疲乏的影响.将60例行根治术并完成第二周期化疗,接受第三周期化疗的乳腺癌患者随机分为四组,每组15人,对照组行医院常规护理;试验组分为A、B、C三组,除常规护理外按护士制定的有氧运动干预方式分别于化疗后第1天、化疗后第3天,化疗结束后规律锻炼.使用修订的Piper疲乏量表(RPFS)对四组患者在化疗前2天、化疗后第1天(运动干预之前)和化疗后21天进行评估.结果化疗前2天四组RPFS得分均无差异(P＞0.05),化疗后21天对照组RPFS得分均高于试验组,试验C组RPFS得分高于试验A、B组.因此,化疗后及早活动能有效缓解患者的癌因性疲乏.     

Laterality and human evolution

The question of whether there is a fundamental discontinuity between humans and other primates is discussed in relation to the predominantly human pattern of right-handedness and the left-cerebral representation of language. Both phenomena may go back at least to Homo habilis, 2-3 million years ago. However, a distinctively human mode of cognitive representation may not have emerged until later, beginning with H. erectus and the Acheulean tool culture about 1.5 million years ago and culminating with H. sapiens sapiens and rapid, flexible speech in the last 200,000 years. It is suggested that this mode is characterized by generativity, with multipart representations formed from elementary canonical parts (e.g., phonemes in speech, geons in visual perception). Generativity may be uniquely human and associated with the left-cerebral hemisphere. An alternative, analogue mode of representation, shared with other species, is associated with the right hemisphere in humans.     

Laterality and field dependence

The purposes of this study were (1) to replicate a right visual-field advantage for a version of the Embedded Figures Test modified for tachistoscopic presentation and (2) to test for a relationship between field independence and performance on modified Embedded Figures Test items presented to the right visual-field. 34 right-handed subjects were presented Embedded Figures Test items to the left, center, and right visual-fields for 150 msec. The Group Embedded Figures Test was also given. Results showed a right visual-field advantage on the modified embedded-figures test and (2) a negative relationship between Group Embedded Figures Test performance and right visual-field scores. These findings were discussed in terms of the differences between the two versions of the embedded-figures test, memory for simple figures, specificity of judgment, and sustained versus tachistoscopic perception. A tentative conclusion suggests that a better internal representation of the briefly presented complex figures places field-independent subjects at a disadvantage on the modified version of the test.     

Gender Effects on Reaction Time Variability and Trial-to-Trial Performance: Reply to Deary and Der (2005)

ABSTRACT

Deary and Der (2005) Deary, I. J. and Der, G. 2005. Reaction time, age, and cognitive ability: Longitudinal findings from age 16 to 63 years in representative population samples. Aging, Neuropsychology and Cognition, 12: 187–215. [CSA][Taylor & Francis Online], [Web of Science ®] , [Google Scholar] reported significant gender effects on intraindividual variability in choice reaction time (CRT), and suggested several potential causes. In their procedure it was not possible to examine RTs on a trial-to-trial basis. We therefore investigate an additional possible cause: that men and women differ in their rate of performance improvement across trials, creating an apparent difference in variability. Using data from a large online CRT study, we replicate the finding that women are more variable in RT than men. However, we also demonstrate an interaction between gender and trial number for RT: women were initially slower than men, but became faster than men across a block. When the first two trials of the block are excluded, the gender effects on RT variability disappear.     

Everyday Life Cognitive Instability Predicts Simple Reaction Time Variability: Analysis of Reaction Time Distributions and Delta Plots

The goal of this study is to understand the interface between subjectively assessed and objectively measured attention functioning. To this end, we assessed both self‐report data using the Cognitive Failures Questionnaire (CFQ) and sustained‐attention performance using a low‐demand psychomotor vigilance task that required participants to respond to visual targets. Unlike previous studies, reliability of task performance was ensured, testing individuals twice within a retest interval of 1 week. Given that everyday life attentional lapse tendencies vary even in normal‐population samples, we asked whether there is a relationship with laboratory performance, in general and as a consequence of time on task (TOT). As a result, low (versus high) CFQ scorers were somewhat different in their average response speed but became particularly prone to lapsing during the task period, as reflected in standard measures of response‐speed variability as well as ex‐Gaussian parameters of distributional skewness. In conclusion, we argue that persistence to sustained demand might be an important aspect of construct validity that must be evoked by a manipulation of TOT, which may be useful for the evaluation of questionnaires in ecologically valid situations. Copyright © 2015 John Wiley & Sons, Ltd.     

反应时方法的新进展

反应时以数量化的方式来反映人的各种心理和生理指标,是实验心理学中常用的反应变量之一。反应时经过两个发展阶段之后,在认知心理学(特别是内隐社会认知研究)和测量仪器两个方面又有了新的发展。由于反应时是时间和速度的测量内容,为了保证研究结果的准确性,在采用反应时法时必须考虑速度-准确性权衡问题。     

Personality and Reaction Time after Sleep Deprivation

The relationship between reaction time and both state and trait personality variables was investigated in 37 participants after 30 h of sleep deprivation. Regression analyses suggested that endorsement of greater Novelty Seeking, anger/hostility, and depression/dejection, and less confusion, was associated with greater reaction time declines on one Multi-Attribute Task Battery index after sleep deprivation. Further, greater Novelty Seeking and depression/dejection, and less vigor/activity, was associated with greater reaction time declines after sleep deprivation on another Multi-Attribute Task Battery index. Additional correlational analyses indicated that better reaction times were associated with greater Novelty Seeking and lower anger/hostility prior to sleep deprivation, and less confusion/bewilderment following sleep deprivation. Findings suggest that both state and trait personality variables are associated with reaction time performance following sleep deprivation.     

Effective Analysis of Reaction Time Data

The Psychological Record - Most analyses of reaction time (RT) data are conducted by using the statistical techniques with which psychologists are most familiar, such as analysis of variance on the...     

The Effect of Movement Amplitude and Target Diameter on Reaction Time

Siegel’s (1977) interpretation that his reaction time results were solely a function of response factors (movement amplitude and target diameter) was discussed and criticized. It was argued that Siegel’s interpretation was inappropriate because stimulus factors (eccentric and visual angle) and response factors were confounded. It was also argued that the surprising U-shaped relation between reaction time and movement amplitude was probably the result of the confounding between stimulus and response factors.     

Laterality of Champion Athletes

Certain experimental designs are based upon the assumption that performance level becomes stabilized after a prolonged period of practice. This assumption was tested by taking a long series of repeated measurements upon a single S for the performance of each of several constant tasks, each task being tested singly in a separate series of measurements. Results showed that after thousands of practice trials on a simple task S may still be learning or showing other sequential effects in performance. These effects may disappear on one day only to reappear on the next. Therefore it is extremely doubtful that “practice to an asymptote” should be regarded as either an efficient or an effective method of eliminating sequential effects from an experiment proper.