Simple reaction time as a function of response complexity: memory drum theory revisited

The prediction emanating from memory drum theory (Henry & Rogers, 1960') that simple reaction time (SRT) increases as a response becomes more complex (i.e., increases in number of movement parts) was investigated. Experiments 1 (N = 20) and 3 (N = 16) indicated that SRT was longer for responses consisting of two and three parts than it was for a one-part response and this may be interpreted as support for the prediction. Failing to support the prediction, however, was the finding that SRT was essentially the same for responses consisting of two and three parts. This may not be too damaging to the theory because it could simply be reflecting an upper limit in terms of numbers of parts or response duration for causing an increase in SRT. Experiments 2 (N = 20) and 3 revealed an SRT effect between two responses that were supposed to be equal in complexity. At first, this finding appeared to be contrary to the prediction, but it may be interpreted as support for it because one of the responses defined as having one movement part could actually have had two     

Phoneme-monitoring reaction time as a function of preceding intonation contour

An acoustically invariant one-word segment occurred in two versions of one syntactic context. In one version, the preceding intonation contour indicated that a stress would fall at the point where this word occurred. In the other version, the preceding contour predicted reduced stress at that point. Reaction time to the initial phoneme of the word was faster in the former case, despite the fact that no acoustic correlates of stress were present. It is concluded that a part of the sentence comprehension process is the prediction of upcoming sentence accents.     

Fractioned reaction time in power-trained and endurance-trained athletes under conditions of fatiguing isometric exercise

Fractionated knee extensor and plantar flexor reaction time (RT) components were assessed in a group of eight weightlifters and eight long distance runners. Following a 4-day period of baseline stabilization for each muscle group, a 50% maximal voluntary contraction (MVC) holding-time exercise was administered. Results showed that the runners had longer premotor times (PMT) than the weightlifters in the knee extensors, but had much faster PMTs than the lifters in the plantar flexor condition. Compared to previously reported investigations using non-athletes, the data for the present sample of athletes indicated faster total reaction times(TRT) in both the knee extensors and the plantar flexors. A resistance of 15% MVC applied during the RT task resulted in a lengthening of the motor time (MT) component in both groups prior to exercise. However, while knee extensor resisted motor time was lengthened by the exercise task, no such lengthening occurred in plantar flexor resisted RT. It is concluded that power-trained and endurance-trained athletes exhibit difference in response to a fractionated RT task, under both baseline and fatiguing exercise conditions.     

Ready-signal effects as a function of experimental design in simple reaction time

In the between-S design, 20 Ss had a visual ready signal presented on each trial; for another 20 Ss, the ready signal was always absent. The within-S design consisted of 40 Ss that experienced both ready-signal conditions in semirandom order. Two intensities of a 1,000-Hz tone were used as the response signals Ready-signal manipulation had pronounced effects under the within-S but not the between-S design irrespective of response-signal intensity     

Identification reaction time as a function of target and field object orientation

Four experiments were conducted investigating the effects of (a) target versus field object orientation, (b) target upside up versus target upside down and (c) inverting versus noninverting lenses on object identification reaction time. Inverting versus noninverting lenses had no significant effect. Target versus field orientation was significant when objects commonly found on a desk were used. Target upside up versus upside down was not significant. With letters as target and field objects, orientation was not significant. When the target letters were simply inverted (rotated 180 degrees on the horizontal axis), however, forming nonfamiliar patterns, the target upside up versus upside down was significant, with the upside down condition resulting in a longer mean reaction time. The complexity and similarity of target and field objects is offered as an explanation of the results.     

Effect of loudness on reaction time and response force in different motor tasks

Van der Molen and Keuss, in 1979 and 1981, showed that paradoxically long reaction times occur with extremely strong auditory stimuli when the task is difficult, e.g., choice-by-location or Simon paradigm. It was argued that this paradoxical behavior of RT is due to active inhibition of an arousal-dependent bypassing mechanism to prevent false responses. As the peak force, i.e., maximal force exerted by participants on a response key, is considered to be related to immediate arousal, we predicted that for extremely loud stimuli and for difficult tasks, lengthening of RT should be associated with reduction of peak force. Moreover, these effects should be enhanced when emphasis is on accuracy rather than speed. Although the relation between RT and intensity depended on task difficulty, no increase in RT was found for the loudest tones. Moreover, peak force increased monotonically with loudness, showing no tendency to be suppressed for loudest tones and difficult tasks.     

Fast breathing facilitates reaction time and movement time of a memory-guided force pulse

Slow controlled breathing can be beneficial for performance of continuous and serial motor tasks. However, how controlled breathing influences discrete motor task performance remains unclear. We sought to determine the impact of paced breathing frequency on measures of movement initiation (reaction time: RT), accuracy (absolute endpoint error: AE; constant error: CE), and variability (trial-to-trial variability: V), in a goal-directed discrete motor task. We hypothesized slow breathing would be accompanied by faster RT, reduced AE and CE, and less V compared to faster breathing rates. Participants (N = 47) performed a memory-guided force pulse pinch task targeted at 10% of their maximum voluntary contraction while breathing at metronome-paced slow, normal, and fast frequencies. During each breathing condition, heart rate variability (HRV) as indexed by the standard deviation of ‘NN’ intervals (SDNN) was measured to ensure objective manipulation check of participants breathing at their set pace. Following each breathing condition, participants provided subjective ratings using the Affect Grid and Visual Analog Scales for arousal, hindrance, and dyspnea. Manipulation check results indicated participants correctly breathed at metronome paces, as indexed by increased HRV for slow breathing and decreased HRV for fast breathing. Results indicated that fast breathing reduced reaction time and movement time, and increased ratings of arousal, hindrance, and dyspnea. In contrast, slow breathing increased reaction time, and levels of hindrance and dyspnea were similar to normal breathing. Breathing frequency did not differentially impact accuracy or variability across conditions. Findings provide evidence that breathing frequency affects fundamental movement parameters, potentially mediated by factors other than arousal.     

Slow potential changes and choice reaction time as a function of interstimulus interval

Slow potential changes were recorded over the vertex (C_z) during a choice reaction task. The constant interstimulus interval (ISI) between the visual warning (S₁) and the visual imperative signal (S₂) was either 200, 400, 1000 or 2000 msec. The contingent negative variation (CNV) was not only measured between S₁ and S₂ (CNV₂), but also before S₁ (CNV₁).The main results were: (1) The CNV₂ amplitude showed significant variation as a function of ISI. It reached its maximum with an ISI of 1000 msec. (2) CNV₁ developed only before the short ISIs (200 and 400 msec). (3) When CNV₁ and CNV₂ were summed the differences in CNV amplitudes and durations between different ISIs became smaller. (4) The peak-to-peak amplitude P₁-N₁ of the potential evoked by S₁ was enhanced with short ISIs. (5) The correlations between mean CNV and median reaction time (RT) were low but significant for ISIs of 400, 1000 and 2000 msec. When, however, the effect of subjects was partialized out these correlations were drastically reduced, whereas the partialization of session and block effects had no noticeable influence on these correlations. (6) The correlations between single RT and single CNV (measured for the ISI of 1000 msec, individually for two subjects) were weak or even completely lacking.The main conclusion was that CNV coincides with preparedness to react to a stimulus in a choice RT-task, but its amplitude at the moment of onset of the imperative stimulus does not reflect, or reflects weakly, the degree of preparedness (as indicated by RTs) at that moment.     

Decreases in simple reaction time as a function of stutterers'' participation in a behavioral therapy

Stutterers and fluent speakers were compared on a simple reastion time task to determine whether participation in a behaviorally based stuttering program had an effect on clients' reaction time scores. A group of fluent speakers was used to control the possibility that any changes in reaction time latency were due to practice or familiarity with the task. All participants responded with a finger-lift as quickly as possible to 25 visual stimuli presented by computer. Response latencies from the stutterers and the fluent speakers were compared. Stutterers' posttherapy reaction time latencies were significantly shorter than their pretherapy latencies. It was also observed that stutterers' reaction time scores prior to therapy did not differ significantly from fluent speakers' scores. However, stutterers' posttherapy reaction time scores did differ significantly from fluent speakers' posttest scores. The results are discussed in terms of arousal, motivation, familiarity with the environment, conditioned inhibition, and two aspects of therapy.     

Inhibition of return: sensitivity and criterion as a function of response time

Inhibition of return (IOR) refers to a mechanism that results in a performance disadvantage typically observed when targets are presented at a location once occupied by a cue. Although the time course of the phenomenon--from the cue to the target--has been well studied, the time course of the effect--from target to response--is unknown. In 2 experiments, the effect of IOR upon sensitivity and response criterion under different levels of speed stress was examined. In go/no-go and choice reaction time tasks, IOR had at least 2 distinct effects on information processing. Early in target processing, before sufficient target information has accrued, there is a bias against responding to cued targets. Later, as target information is allowed to accrue, IOR reduces sensitivity to the target's nonspatial feature. Three accounts relating to the early bias effect of IOR and the late effect of IOR on sensitivity are offered.     

Perceived persuasiveness as a function of response style: Multi-issue consistency over time

This experiment studied the effect of an individual's response style on different issues over a long period of time. A hypothetical situation depicted the repeated responses given by one person on a target issue and on four other issues for one year. The 2 × 2 × 2 factorial design varied consistency of the stimulus person's position on the target issue during the year (consistent or variable); his consistency on other issues during the year (consistent or variable); and social context (alone or dissenting group). Subjects were 155 college students. Results showed an interaction between consistency on the target issue and consistency on other issues for the three dependent measures (p < .001). That is, significantly greater persuasiveness, confidence, and dis-positional causality were attributed to stimulus persons whose opinions were either completely consistent or completely variable on all issues during the year. Results suggest that the consistency of response style across issues—and not the constant advocacy of a specific position–is the crucial factor in the effectiveness of a long-term minority influence.