Role of Sensory Experience in Parcellation of Sensory Neocortex

Georgia State University Research Foundation, Inc., Atlanta GA

Investigators

Abstract

The broad goal of my experiments is to determine how different areas of mammalian cerebral cortex become specialized to process different types of sensory information, and in particular, how functionally specialized brain circuitry is created during development from non specialized brain tissue. The hypothesis I am testing is that the sensory inputs received during development play a critical role in organizing specific circuits in cortex. To this end, I use three groups of animals; one group of normal animals, one which has had sensory input to auditory cortex (AI) removed (deafened), and another which has had visual input unilaterally diverted into the auditory pathway early in development ("rewired"). We have demonstrated that visual inputs can be processed by auditory cortex if they are present from early in development, and our goal is to determine what changes in auditory cortical circuitry are responsible for the gain of function. The implications of this work are that it provides a uniquely valuable developmental model for mammalian brain evolution. During evolution, neocortex becomes increasingly subdivided, and input processing is increasingly specialized. With our model, we can create a new cortical area or a new input to an existing cortical area on an experimentally-manageable time scale. In addition, the work addresses the basic mechanisms by which an animal's brain becomes adapted to its environment on both an evolutionary and a developmental time scale.