Kolloquium: Learning Novel Sensorimotor Maps

The Center for Lifespan Psychology at the Max Planck Institute for Human Development, led by Prof. Ulman Lindenberger, cordially invites all interested to attend its colloquium:

Floris van Vugt, McGill University, Canada

Learning Novel Sensorimotor Maps

Sensorimotor maps are at the heart of what enables us to point to visual objects or produce speech sounds. A wealth of experimental investigation documents how maps, once learned, are adjusted. In this talk I will present data that explores the earliest stages of learning in which these maps are not yet learned and have to be constructed from the ground up. An audiomotor map learning paradigm is used in which participants learn to make arm movements to sounds. Since arm movements normally do not result in sounds, subjects are in a unique situation where they have to learn a mapping from scratch. What is the learning mechanism underlying this acquisition? In order to answer this question I will present several lines of evidence using behavioural, neuroimaging, and neurochemical spectroscopy techniques, which indicate first that the map learning mechanism does not depend on error correction or motor outflow and does not require structural correspondence between motor and sensory dimensions. Neural structures subserving learning form a widespread network including cortical sensory and (pre)motor areas as well as cerebellum, basal ganglia and parietal regions. The neurochemical basis of map learning appears to rely glutamate-dependent excitatory processes that intiate plastic changes early on and GABA-dependent inhibitory processes that stabilize the newly learned state. Taken together, these findings point to a flexible and powerful mechanism that allows formation of maps that form the basis for human motor control.