Proactive Adjustments of Response Strategies in the Stop-Signal Paradigm

• Published in: Journal of experimental psychology. Human perception and performance Vol. 35; no. 3; pp. 835 - 854
• Main Authors: Verbruggen, Frederick, Logan, Gordon D
• Format: Journal Article
• Language: English
• Published: United States American Psychological Association 01.06.2009
• Subjects: Attention; Choice Behavior; Cognitive Processes; College Students; Computation; Cues; Discrimination Learning; Experimental Psychology; Experiments; Guessing (Tests); Humans; Inhibition (Psychology); Models, Psychological; Pattern Recognition, Visual; Pitch Perception; Psychomotor Performance; Psychophysics; Reaction Time; Second Language Learning; Sensory Thresholds; Set (Psychology); Task Analysis; Tennessee; Tennessee
• ISSN: 0096-1523
• DOI: 10.1037/a0012726

In the stop-signal paradigm, fast responses are harder to inhibit than slow responses, so subjects must balance speed is the go task with successful stopping in the stop task. In theory, subjects achieve this balance by adjusting response thresholds for the go task, making proactive adjustments in response to instructions that indicate that relevant stop signals are likely to occur. The 5 experiments reported here tested this theoretical claim, presenting cues that indicated whether or not stop signals were relevant for the next few trials. Subjects made proactive response-strategy adjustments in each experiment: Diffusion-model fits showed that response threshold increased when participants expected stop signals to occur, slowing go responses and increasing accuracy. Furthermore, the results show that subjects can make proactive response-strategy adjustments on a trial-by-trial basis, suggesting a flexible cognitive system that can proactively adjust itself in changing environments. (Contains 9 figures, 6 tables, and 3 footnotes.)