CHOICE REACTION TIME AS A FUNCTION OF ANGULAR STIMULUS-RESPONSE CORRESPONDENCE AND AGE

Abstract
This study was concerned with the effect of varying the angular orientation of a display on the choice reaction times of two age groups ; a younger group ranging in age from 20 to 30 and an older group aged from 65 to 86. Two stimulus lights mounted on a vertical circular panel were rotated counterclockwise so that the lights formed angles of 0°, 45°, 90°, 135°, and 180° with the horizontal. Changing the spatial relationship of the stimulus lights relative to the fixed position of two response keys increased the complexity of the task and provided a means for testing the hypothesis that age differences in reaction time increase with increasing task difficulty. Results indicated significant differences in reaction time as a function of both display angle and age. With the least compatible display (180°), reaction time was slowed 30%. The role of spatial cues in the process of translating display information into control action was discussed. The predicted interaction of task difficulty and age was not significant.