The influence of the intensity of the stimulus on the length of the reaction time (summary)

The influence of the intensity of the stimulus on the length of the reaction time

Cattell, J. M. (1948). The influence of the intensity of the stimulus on the length of the reaction time, 1885. In W. Dennis (Ed), Readings in the history of psychology. (pp. 323–325). East Norwalk, CT, US: Appleton-Century-Crofts.

After the work of Wundt, Exner, and others, Cattell and Berger were carrying out further experiments to determine the relationship between intensity of a stimulus and reaction time in the Psychological Laboratory at the University of Leipzig. These experiments focused on electric shocks and light, and their effects on simple reaction time and reaction time complicated by other cerebral operations. "Reaction time" refers to the time between the presentation of a stimulus and the beginning of a muscular contraction.

Cattell and Berger experimented on themselves with eight different light intensities. In a second study, they investigated four different intensities of electric shocks on reaction time. Both studies concluded that as stimulus intensity increases, reaction time decreases.

In a third study, the researchers began to wonder whether the colour of the light made a difference. They found, however, that reaction time and light colour were not correlated. They did, however, find that when it was necessary to distinguish the colour of the light before reacting, reaction time increased. It was found, therefore, that the time it takes to perceive a colour becomes shorter as the light intensity increases, but the time it took to perceive a colour was not a function of the intensity of the stimulus.