A. Riehle et al., NEURONAL CORRELATES OF SENSORIMOTOR ASSOCIATION IN STIMULUS-RESPONSE COMPATIBILITY, Journal of experimental psychology. Human perception and performance, 23(6), 1997, pp. 1708-1726
Neuronal mechanisms underlying stimulus-response (S-R) associations in
S-R compatibility tasks were identified in 2 experiments with monkeys
. Visual stimuli were presented on the left and right calling for left
-right movements under congruent and incongruent S-R mapping instructi
ons. High- and low-pitched tones calling for left-right movements were
presented to the left and right ear, and the stimulus side was irrele
vant. Single neurons sensitive to the S-R mapping rule were found in t
he primary motor cortex. The large overlap between the neuronal popula
tions sensitive to the stimulus side, the S-R mapping rule, and the re
sponse side, respectively, is consistent with the idea that sensory-to
-motor transformation is a continuous rather than a discrete process.
Results partly support the hypothesis that the increase in reaction ti
me with incongruent mapping is caused by the automatic activation of t
he congruent, but erroneous, response.