Motor precision shapes information seeking in perceptual decisions

Adaptive behavior relies heavily on the confidence we have in our decisions. For instance, in the absence of explicit feedback, the confidence associated with a decision determines whether we seek additional evidence or are likely to change our mind. Recent studies suggest that confidence estimation also depends on motor processes involved in implementing perceptual decisions. However, whether motor-induced changes in confidence meaningfully affect behavior, such as by altering information-seeking, remains uncertain. The present study addresses this question. Participants performed a perceptual task requiring discrimination of the orientation of Gabor patches. The motor cost of the perceptual response was manipulated by varying the size of the response circles that participants had to reach to report their judgment. Consistent with previous findings showing that easier motor responses are associated with lower confidence ratings, we found that such responses were also linked to a greater tendency to seek additional evidence compared to more costly responses. Importantly, this increase in information-seeking behavior was not accompanied by any change in perceptual accuracy. These findings support the idea that the motor costs associated with perceptual decisions modulate confidence, and that such motor-induced changes in confidence play a functional role in guiding subsequent behavior.