Choice Reaction Time Performance Research Articles

Categorizing and choice reaction time performance

The visual search time for the presence of both of two physical stimuli was measured under two conditions: (1) conceptual identity-the targets being upper and lower case forms of the same letter (C.1); and (2) upper and lower case forms of different letters (D). It was hypothesized that C.1 would facilitate the simultaneous analysis of the features of two letters in a visual display. Each subject searched for the two classes of stimuli on alternate days. Responses in the C.1 condition were found to be significantly faster than in the D condition. RT was shorter for an affirmative than for a negative response, but there was no interaction between conditions and affirmative or negative responses. The results are considered in relation to the concept of categorizing.

The Effects of Whole Body Exercise on Choice-Reaction Time Performance

A study which investigates how cognitive performance is affected by simultaneous, physical exercise is reported. Whole body exercise on a bicycle ergometer at four work loads (30, 60, 120 and 180 watts) and four rates (30, 40, 60 and 90 rpm) for durations of from 5 to 25 minutes were investigated. A two-stage choice reaction time task was performed at one minute intervals prior to, during and after exercise. Psychomotor performance was measured by reaction time and error rate. Although the subjects were fully trained, very pronounced subject differences were noted. The psychomotor response did not vary with work load (watts) or work rate (rpm), and in addition, was not related to the physiological measurements recorded for heart rate and oxygen consumption. Nominal differences in reaction time and error rate were detected during and after exercise; but it was concluded that physical exercise, even if strenuous, does not cause a modification in cognitive performance of practical significance.

Effects of Interstimulus Interval on Continuous Choice Reaction Time Performance in Brain-Damaged, Alcoholic and Control Patients

The effect of two interstimulus intervals (2.5 and 4.0 secs) upon performance on a continuous choice reaction time test (CRT) was investigated in three groups of male veterans: brain-damaged (N = 24), alcoholic (N = 24), and control (N = 24) patients. Compared to the other two groups, brain damaged had significantly longer RTs and significantly greater differences between RTs for the two interstimulus intervals. Alcoholics did not differ from controls on any performance measure. These results and those of other studies support the conclusion that impaired response initiation may play an important role in CRT deficits in brain damage.

The effects of differential amounts of stimulus familiarization on choice reaction time performance in children

Groups of first-grade children were exposed during a familiarization phase to 0, 1, 10, 20, or 40 3-second presentations of a red or a green light. On 49 subsequent choice reaction time trials, the familiarized stimulus (FS) and nonfamiliarized stimulus (NS) each served as the signal to respond on half of the trials and were presented according to one of two sequences. Both sequences involved 50% alternation and 50% repetition of the two types of stimuli. Release but not travel speeds were sensitive to the effects of familiarization. Release speeds were faster to the NS than to the FS for Ss given 20 or 40 familiarization exposures but not for those given 0, 1, or 10 exposures. The magnitude of this effect was comparable for Ss given 20 or 40 exposures. A change effect (CE) was found for both release and travel speeds except in the case of travel speed for Group 0. The CE findings can be accounted for by either a stimulus interpretation or a modified response interpretation.

Correction for guessing in choice reaction time

Additional theoretical and experimental results are presented for a choice reaction time performance model described by Oilman (1966). A formula is given for estimating the latency distribution of true recognition responses from the results of a single session; the estimate is invariant with respect to changes in the proportion of “guess” responses and with respect to fluctuations in the latency distribution of guesses.