Reaction time to single and to first signals.

Abstract

Choice reaction times were measured for 6 adult Ss by 2 procedures. There was a Single-Choice condition in which, after a fixed warning interval, S was required to move a lever away from himself or toward himself according to which of 2 signal lamps was lighted. In the doublechoice condition, there followed J sec. after the 1st signal a 2nd choice involving 2 other signal lamps and a choice by the other hand. For each S, mean reaction time for the Single-Choice condition was reliably shorter than that for the 1st choice in the Double-Choice condition. This was regarded as corroboration of Poulton's thesis that a person's manner of response, including latency, is influenced by his expectations of the requirements of the immediate future.

Effects of time and event uncertainty upon sequential information processing

“…First, RT1 was longer than the simple single RT means. This delay in RT 1 replicates a previous finding by Gottsdanker, Broadbent and Van Sant (1963).…”

“…Although both of these findings are in need of further investigation, it would seem justified at present to assume that an expectancy theory cannot adequately account for these two delays; thus, both findings support the conclusions reached by Smith (1967) and Bertelson (1966) that the PRP is a consequence of single channel delays. However, it should be noted also that factors which delay RTl' some of which were previously noted by Gottsdanker, Broadbent, and Van Sant (1963), are difficult for single channel theories to account for. These theories are concerned with sources of the proactive effects of SI upon S2 and not the converse.…”

Reaction Time to a Second Stimulus as a Function of Intensity of the First Stimulus

“…This increase is the same for both intensities of the first stimulus, and is approximately the same mean increase (42 millisec.) reported by Gottsdanker, Broadbent and Van Sant (1963) in a study designed to explore the difference between first RTs and RTs to a single stimulus.…”

“…Others, however, have found no change in RT, (Davis, 1956), or a slight increase in RT, which is the same across all ISIs (Smith, 1966). Gottsdanker, Broadbent and Van Sant (1963) compared mean first RT at an IS1 of 500millisec. with the choice RT to that stimulus presented alone, and found the former to be significantly larger.…”

Choice reaction time as a function of intersensory anticipation

“…However, other experiments (Lappin & Eriksen, 1964;Koplin, Fox, & Dozier, 1966) have failed 10 replicate this increase in simple RT. Gottsdanker, Broadbent, & Van Sant (1963) found inhibition of RT to occur in a choice·RT situation. They measured choice RT for six adults under two conditions.…”