The Modification of an Already-Programmed Response: A New Interpretation of Henry and Harrison (1961)

Abstract

In an influential study, Henry and Harrison (1961) examined the capability of subjects to inhibit an already-programmed response. Their experiment showed that when a stop signal was presented only 100 ms after the imperative go signal, a subject could not inhibit the movement. The inferences were that rapid ballistic actions are programmed and the program cannot be altered in a limited amount of time (see Schmidt, 1988). In the present note, we describe some forgotten data from the Henry and Harrison paper and, with a trend analysis, demonstrate that the stop signal does have an influence on the movement in a somewhat continuous fashion.

Key Words:

• motor programming
• response inhibition
• response latency