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0898-929X
E-ISSN
1530-8898
2014 Impact factor:
4.69

Journal of Cognitive Neuroscience

May 1999, Vol. 11, No. 3, Pages 321-329.
(doi: 10.1162/089892999563427)
© 1999 Massachusetts Institute of Technology
Accessory Stimulus Effects on Response Selection: Does Arousal Speed Decision Making?
Article PDF (132.82 KB)
Abstract

When an intense but task-irrelevant “accessory” stimulus accompanies the imperative stimulus in a choice reaction task, reaction times (RTs) are facilitated. In a similar previous study (Hackley & Valle-Inclán, 1998), we showed that this effect is not due to a reduction of the interval from onset of the lateralized readiness potential (LRP) until movement onset. In the present study, the RT task was modified to move a portion of the response selection stage into this time interval. The interval remained invariant, indicating that this late phase of the response selection process is not speeded by accessory stimulation. However, we observed amplitude modulation of the LRP on no-go trials in a condition with three alternative responses. This finding suggests that an earlier phase of response selection is influenced by accessory stimulation. In addition, a novel dependent measure was introduced to event-related potential research—the latency of spontaneous, posttrial blinking.