Neural Reuse in the Evolution and Development of the Brain: Evidence for Developmental Homology?

Department of Psychology, Franklin & Marshall College, P.O. Box 3003, Lancaster, PA 17604-3003. .
Developmental Psychobiology (Impact Factor: 3.31). 01/2013; 55(1). DOI: 10.1002/dev.21055
Source: PubMed


This article lays out some of the empirical evidence for the importance of neural reuse-the reuse of existing (inherited and/or early developing) neural circuitry for multiple behavioral purposes-in defining the overall functional structure of the brain. We then discuss in some detail one particular instance of such reuse: the involvement of a local neural circuit in finger awareness, number representation, and other diverse functions. Finally, we consider whether and how the notion of a developmental homology can help us understand the relationships between the cognitive functions that develop out of shared neural supports. © 2012 Wiley Periodicals, Inc. Dev Psychobiol.

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