What is the Basis of Choice Reaction-Time ?
Alan T. Welford · Ergonomics · 1971
In an 8-choice reaction task times for responses by the ring and middle fingers were found to be substantially longer than those for responses by the index and little fingers. Supplementary experiments showed that the inequalities were not due to motor factors but rather to perceptual features which affected the ease with which the positions of signals and response keys could be identified. The inequalities observed are incompatible with several types of model which have been proposed to account for the linear rise of reaction-time with the logarithm of degree of choice; in particular, the serial classification model which assumes a simple progressive dichotomization, and models which assume that evidence from all the possible signal sources is examined simultaneously. However, the times for 2-, 4- and 8-choice tasks accorded remarkably well with predictions from a modified serial-classification model proposed by the author in 1960.