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1.
Abstract

The theory proposes a nonconscious mechanism that uses stored information (motor memory) to channel existing nervous impulses from brain waves and general afferent stimuli into the appropriate neuromotor coordination centers, subcenters, and efferent nerves, thus causing the desired movement. A consequent hypothesis requires that the simple reaction time will become longer when the response movement is required to be of greater complexity. Data obtained on college men and women, and 12- and 8-year-old boys, are in agreement with the hypothesis. Replacing a very simple finger movement with an arm movement of moderate complexity slows the reaction by about 20 percent; additional complexity produces a further slowing of 7 percent. The speed of the arm movement is considerably faster in college men than in younger boys or in college women. The correlation between reaction time and speed of movement averages approximately zero. Individual differences in ability to make a fast arm movement are about 70 percent specific to the particular movement being made; “general ability for arm speed” occurs only to the extent of 30 percent.  相似文献   

2.
Abstract

Two experiments were conducted to identify the response elements responsible for the complexity effect found by Henry and Rogers (1960). An attempt was made to determine if these elements were affecting the premotor time component of simple reaction time (SRT). If they were, a strong case could be made for the argument that neuromotor programming time was affected because premotor time is a more exact estimate of it than SRT. The results revealed that premotor time was unaffected by a forward change in movement direction, but increased as the number of movement parts increased from one to two and as the demand for movement accuracy increased. Thus, increasing the (1) number of parts and (2) accuracy demands were identified as elements of response complexity which increase programming time and support Henry and Rogers (1960) hypothesis that the time to initiate a response becomes longer as the programming process become more complex.  相似文献   

3.
Abstract

Using a visual Go/Nogo paradigm and subtraction methods, we examined detailed developmental changes in the cognitive reaction times of 153 healthy children aged 6–12 years. Three conditions were studied: simple reaction, even rate reaction (50% Go), and high rate reaction (80% Go). The subtraction of simple reaction time from even rate reaction time was considered to reflect discrimination time, while the subtraction of simple reaction time from high rate reaction time was considered to reflect the time required for inhibition. We found that simple reaction time, even rate reaction time, and high rate reaction time all declined significantly with months of age (P < 0.01). Furthermore, the times for both discrimination and inhibition also showed significant declines (P < 0.01), which could be considered developmental changes in neural mechanisms involved in discrimination and inhibition processes. The time for inhibition showed a weaker correlation (P < 0.01), which could indicate that the degree of developmental change is larger for the discriminative processes than for the inhibititory processes required for our task in the age range studied.  相似文献   

4.
Abstract

The possible effects of normal involuntary blinking upon reaction time measures were investigated through a comparison of blink rates and the incidence of blinking in relation to preparatory signal, response signal, and the subject's response. Analysis of the data revealed that: (1) the frequency of blinking was markedly decreased during reaction time responses, (2) blinking was generally inhibited between presentation of the preparatory signal and the subject's response, and (3) blinks coincided with presentation of the response signal in only 0.1 per cent of the cases. The results indicated that blinking has little effect upon reaction time measures.  相似文献   

5.
Abstract

Two alternative interpretations to the one proposed by Christina, Fischman, Vercruyssen, and Anson (1982) were investigated. They interpreted the simple reaction time (SRT) increase they found, which was thought to reflect an increase in programming time, to be due to the increase in number of movement parts from one response to another. Experiment 1(N = 15 males) tested the alternative interpretation that the SRT increase was caused by the difference in how the first movement part of the three responses was executed. However, no evidence was found to support this interpretation. Experiment 2 (N = 15 males) tested the alternative interpretation that the SRT increase was due to the increase in the demand for movement accuracy from one response to another. The results revealed that only a very small portion of the SRT increase could be attributed to the increased accuracy demand while the major portion of the increase was due to the increase in number of movement parts.  相似文献   

6.
Abstract

The aim of this study was to test the effect that changing targets during a simple long lunge attack in fencing exerts on the temporal parameters of the reaction response, the execution speed, and the precision and the coordination of the movement pattern. Thirty fencers with more than 10 years of experience participated in this study. Two force platforms were used to record the horizontal components of the reaction forces and thereby to determine the beginning of the movement. A three-dimensional (3D) system recorded the spatial positions of the 9 markers situated on the fencer plus the epee, while a moving target was projected on a screen, enabling the control of the target change. The results indicated that when a target change is provoked the reaction time (RT), movement time (MT), and the time used in the acceleration phase of the centre of mass (CM) increases significantly with respect to the attack executed with a straight thrust. The speed and horizontal distance reached by the CM at the end of the acceleration phase (VX(CM) and SX(CM), respectively) significantly decreased, while the errors increased. However, the temporal sequence of the movement pattern did not appreciably change.  相似文献   

7.
Abstract

The aim of this study was to examine the facilitating effects of physical exercise on the reaction process. Eleven participants with specific expertise in decision-making sports performed a choice reaction time task during moderate sub-maximal exercise (90% of their ventilatory threshold power). Participants were tested at rest and while cycling. During exercise, the participants were faster, without being more variable. We suggest that the effect of exercise on cognitive performance was due to a major generalized improvement of the whole distribution of response time and, although the benefit effect was small, it was consistent throughout the entire range of reaction times.  相似文献   

8.
Purpose: The influence of attention on postural control and the relationship between attention and falling has been reported in previous studies. Although a dual-task procedure is commonly used to measure attentional demand, such procedures are affected by allocation policy, which is a mental strategy to divide attention between simultaneous tasks. Therefore, we examined the effectiveness of salivary α-amylase, which is a physiological method for measuring attentional demand during postural control. Method: Sixteen healthy participants performed a postural-control task using the Balance System, which is a device that can be calibrated to a specific stability level (“Level 1 = least stable” to “Level 8 = most stable”). Levels 1, 2, and 3 were used for this study. Dependent variables measured were overall stability index, which represents the variance of platform displacement in degrees from a horizontal plane; probe reaction time, which was measured using a sound stimulator and recorder; and salivary α-amylase, which was measured using a portable salivary amylase analyzer. Results: As stability level of the test task decreased, both stability index and probe reaction time significantly increased. In addition, we identified a positive moderate correlation between probe reaction time and salivary α-amylase. Conclusions: Our results suggest that salivary α-amylase and probe reaction time reflect the change in attentional demands during a postural-control task and that salivary α-amylase may be an effective tool for evaluating attentional demands during postural control because it is noninvasive and simple to perform.  相似文献   

9.
Abstract

It is well documented that simple reaction time (RT) varies inversely with stimulus intensity, but there is disagreement as to which stimulus modality produces the fastest simple RT. An investigation was conducted to equate two stimulus modalities, auditory (A) and electrocutaneous (EC), using varying stimulus intensities in a simple RT protocol. A second investigation was then conducted to examine neuromotor characteristics of stimulus-evoked responses using previously equated A and EC stimuli of varying intensity from the first investigation. Results showed that RT, premotor time (PMT), and motor time (MT) were all inversely related to stimulus intensity, while maximum displacement (MAXD) was directly related to stimulus intensity, and movement time was not affected by stimulus intensity. We conclude that: (a) both central and peripheral components of RT are altered by varying stimulus intensities, and (b) rapid movements are enhanced by increasing stimulus intensity.  相似文献   

10.
Reaction time, fractionated reaction time (premotor and motor time), and movement time were recorded during performance of a rapid aiming movement (11 mm in amplitude) to a circular target. Independent variables were target diameter (2 or 64 mm) and reaction time condition (simple or choice). Fifty-two subjects performed 16 practice and 24 performance trials under one of four possible experimental combinations (13 subjects per combination) in a 2 × 2 design. Reaction time correlated highly with premotor time (r = .99) but not with motor time (r = .31). Choice reaction time and its premotor time component were dependent upon target diameter, but simple reaction time and its premotor time component were not. However, choice and simple motor time were not differentially affected by target diameter. As expected, movement time was longer for the small target than for the large target. Taken together, the reaction time results were interpreted as support for Klapp's (1975) hypothesis that increases in choice reaction time for rapid movements to a small target are due to increases in the time needed for programing the response.  相似文献   

11.
Abstract

Sixty-six college women enrolled in fencing classes provided measures of reaction time, response time, and movement accuracy on a specially designed apparatus. The subjects then foil-fenced in round-robin tournaments. Criterion measures of fencing achievement derived from tournament matches correlated little better than zero with reaction time, response time, and movement accuracy.  相似文献   

12.
Purpose

This study investigated whether within-task expertise affects the reported asymmetry in execution time exhibited in reactive and self-initiated movements.

Method

Karate practitioners and no-karate practitioners were compared performing a reverse punch in reaction to an external stimulus or following the intention to produce a response (self-initiated). The task was completed following the presentation of a specific (i.e., life-size image of opponent) or general stimulus and in the presence of click trains or white noise.

Results

Kinematic analyses indicated reactive movement had shorter time to peak velocity and movement time, as well as greater accuracy than self-initiated movement. These differences were independent of participant skill level although peak velocity was higher in the karate practice group than in the no-karate practice group. Reaction time (RT) of skilled participants was facilitated by a specific stimulus. There was no effect on RT or kinematic variables of the different type of auditory cues.

Conclusions

The results of this study indicate that asymmetry in execution time of reactive and self-initiated movement holds irrespective of within-task expertise and stimulus specificity. This could have implications for training of sports and/or relearning of tasks that require rapid and accurate movements to intercept/contact a target.  相似文献   

13.
Abstract

The effect of practice on individual differences and intra-individual variability in reaction and movement times were studied for simple and complex, discrete, motor tasks. Changes with practice for intertrial correlations of adjacent trials and the effects of an increasing number of interpolated trials on intertrial correlations were also observed. For both tasks and for both reaction and movement times, the intra-individual variability decreased with practice. The true score variability for reaction time on both tasks and for movement time on the simple task shows little change with practice. On the complex task, true score variability for movement time decreases with practice. For movement time, adjacent trial correlations increase during the early practice trials then remain stable. For reaction time adjacent trial correlations increase throughout practice. Remoteness effects on intertrial correlations were found for both movement and reaction times for both tasks.  相似文献   

14.
Abstract

This study investigated stimulus velocity effect on manual asymmetry during planning and execution of a complex coincidence-anticipation task. Left- and right-handers were required to press six buttons sequentially in conjunction with visual stimulus provided by a coincidence-anticipation device. Results showed that (1) stimulus velocity affected timing response and timing accuracy only for right-handers, who responded faster but less accurately in the fast stimulus velocity, (2) manual asymmetries for both handedness groups revealed a left-hand advantage for initiating the movement, and a preferred-hand advantage for movement time. The preferred-hand advantage in timing accuracy was only observed in the fast stimulus velocity. These findings are discussed in the framework of the hemispheric functional lateralisation.  相似文献   

15.
Abstract

The speed-accuracy operating curve was investigated in a movement precuing two- or four-choice reaction time task. Four levels of response preferences were manipulated with subject instructions and postresponse information: (a) accuracy, (b) reaction time latency, (c) accuracy and reaction time latency, and (d) no preference. Eighty subjects completed 480 discrete keypressing responses with the index and middle fingers of both hands. The mixed design mean reaction time analysis indicated faster performances for the reaction time latency and the accuracy and reaction time latency groups than the no preference group. Additionally, the percent correct analysis revealed two significant interactions: (a) Trial Block x Precue x Response Preference, and (b) Delay x Precue x Hand Position. Overall, the present findings provide partial support for the speed-accuracy operating curve predictions. Caution is advised when drawing chronometric inferences based only on reaction time data or when response accuracies are extremely high.  相似文献   

16.
Abstract

The aim of the present work is to examine the differences between two groups of fencers with different levels of competition, elite and medium level. The timing parameters of the response reaction have been compared together with the kinetic variables which determine the sequence of segmented participation used during the lunge with a change in target during movement. A total of 30 male sword fencers participated, 13 elite and 17 medium level. Two force platforms recorded the horizontal component of the force and the start of the movement. One system filmed the movement in 3D, recording the spatial positions of 11 markers, while another system projected a mobile target over a screen. For synchronisation, an electronic signal enabled all the systems to be started simultaneously. Among the timing parameters of the reaction response, the choice reaction time (CRT) to the target change during the lunge was measured. The results revealed differences between the groups regarding the flight time, horizontal velocity at the end of the acceleration phase, and the length of the lunge, these being higher for the elite group, as well as other variables related to the temporal sequence of movement. No significant differences have been found in the simple reaction time or in CRT. According to the literature, the CRT appears to improve with sports practice, although this factor did not differentiate the elite from medium-level fencers. The coordination of fencing movements, that is, the right technique, constitutes a factor that differentiates elite fencers from medium-level ones.  相似文献   

17.
Abstract

The purpose of this study was to compare reaction time (RT) and fractionated RT components (premotor and motor times) between normal and postcontraction conditions. Twelve participants performed 20 trials each of control and postcontraction RT conditions. For the control condition, participants executed a learned, rapid, knee-extension contraction response to an auditory stimulus. The postcontraction condition was identical to the control condition except that the participants performed a 3-s isometric contraction of the knee extensor muscles prior to an auditory stimulus. Muscle activity was recorded from the quadriceps muscle group. Results indicated that the postcontraction condition was significantly faster than the control condition for the average RT, premotor time, and motor time. It was concluded that reaction time, processing time, and muscle contraction time for a learned task could be significantly reduced following an isometric contraction.  相似文献   

18.
Purpose: Decline of motor performance in older individuals affects their quality of life. Understanding the contribution of sport-related training in advanced ages might help to attenuate motor performance decay as one gets older. The purpose of our study was to evaluate the extent to which long-lasting training in running or sport-specific skills during old age preserves motor performance in different motor tasks. Method: Older runners and tennis players with at least 10 years of training were assessed as were age-matched and young exercisers. Performance was evaluated for 6 motor tasks requiring different functions of sensorimotor control expected to decline with aging. Results: Analysis revealed that runners had increased aerobic fitness in comparison with the other older participants and that they presented similar performance to older exercisers in the motor tasks. Tennis players outperformed the other groups of older participants on coincident timing and simple reaction time and achieved similar performance to the young group on the timing task. Conclusions: These results suggest selective maintenance of task-specific processing through extensive practice of tennis-related motor skills in older adults.  相似文献   

19.
ABSTRACT

Fractionated reaction time can be used to determine distinct epochs known as pre-motor, response and movement times (MTs) of a reaction time task. The purpose of this study was to compare elite and novice athletes performing a taekwondo kick in terms of the fractionated reaction time and electromyography (EMG) activation patterns of the muscles of the striking lower limb and the lower back. We hypothesised that the pre-motor time, response time (RT) and MT would be the shorter for elite athletes compared to novices. We collected data on 13 elite and 10 novice athletes when performing a roundhouse kick. The experiment included EMG electrodes placed on five low back and lower extremity muscles and an electrogoniometer placed on the kicking knee. We found that pre-motor time was shorter and the RT was longer for elite athletes than novice athletes. Moreover, the integrated EMG of the main knee extensor does not differ between groups though other leg and trunk muscles do. The results allow coaches and teachers to understand this particular taekwondo kicking movement which could ultimately improve the technique in order to establish training and teaching goals.  相似文献   

20.
Abstract

The present study sought to determine whether individuals could be trained to attenuate the visual dominance effect by selecting a proprioceptive stimulus for attention. Using a reaction time (RT) task, subjects received either: (a) visual (V), (b) proprioceptive (P), or (c) combined V and P (VP) stimuli during the first four days. Each subject was then tested under all three stimuli conditions. Results showed that reaction time to the P cue was always faster than that to V or combined VP stimuli. The order in which subjects were tested under each stimulus modality significantly affected the results such that those subjects who received initial exposure to the V stimulus produced the slowest premotor time scores but the fastest motor time scores. These results suggest that the nature of the stimulus which initiates the volitional task can affect both the central processing requirements to initiate the response, and the qualitative manner in which the motor command is executed.  相似文献   

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