Decision-making processes in perceptual learning depend on effectors

Abstract

Visual perceptual learning is traditionally thought to arise in visual cortex. However, typical perceptual learning tasks also involve systematic mapping of visual information onto motor actions. Because the motor system contains both effector-specific and effector-unspecific representations, the question arises whether visual perceptual learning is effector-specific itself, or not. Here, we study this question in an orientation discrimination task. Subjects learn to indicate their choices either with joystick movements or with manual reaches. After training, we challenge them to perform the same task with eye movements. We dissect the decision-making process using the drift diffusion model. We find that learning effects on the rate of evidence accumulation depend on effectors, albeit not fully. This suggests that during perceptual learning, visual information is mapped onto effector-specific integrators. Overlap of the populations of neurons encoding motor plans for these effectors may explain partial generalization. Taken together, visual perceptual learning is not limited to visual cortex, but also affects sensorimotor mapping at the interface of visual processing and decision making.

Competing Interest Statement

The authors have declared no competing interest.

Footnotes

* We have performed several new analyses of reaction times and accuracy data, especially concerning the factor task difficulty, that were requested during peer review. We have also added new figures and re-plotted existing figures in accordance with the peer review. The conclusions of the manuscript remain unchanged. We note that one of the co-authors has changed names.