Behavioral and Brain Sciences

Neural reuse: A fundamental organizational principle of the brain

Michael L. Andersona1

Department of Psychology, Franklin & Marshall College, Lancaster, PA 17604, and Institute for Advanced Computer Studies, Neuroscience and Cognitive Science Program, University of Maryland, College Park, MD 20742.


An emerging class of theories concerning the functional structure of the brain takes the reuse of neural circuitry for various cognitive purposes to be a central organizational principle. According to these theories, it is quite common for neural circuits established for one purpose to be exapted (exploited, recycled, redeployed) during evolution or normal development, and be put to different uses, often without losing their original functions. Neural reuse theories thus differ from the usual understanding of the role of neural plasticity (which is, after all, a kind of reuse) in brain organization along the following lines: According to neural reuse, circuits can continue to acquire new uses after an initial or original function is established; the acquisition of new uses need not involve unusual circumstances such as injury or loss of established function; and the acquisition of a new use need not involve (much) local change to circuit structure (e.g., it might involve only the establishment of functional connections to new neural partners). Thus, neural reuse theories offer a distinct perspective on several topics of general interest, such as: the evolution and development of the brain, including (for instance) the evolutionary-developmental pathway supporting primate tool use and human language; the degree of modularity in brain organization; the degree of localization of cognitive function; and the cortical parcellation problem and the prospects (and proper methods to employ) for function to structure mapping. The idea also has some practical implications in the areas of rehabilitative medicine and machine interface design.


  • brain;
  • development;
  • evolution;
  • exaptation;
  • functional architecture;
  • localization;
  • modularity

Michael L. Anderson, Assistant Professor of Cognitive Science in the Department of Psychology at Franklin & Marshall College, is author or co-author of more than sixty scholarly and scientific publications in cognitive science, artificial intelligence, and philosophy of mind. His papers include: “Evolution of cognitive function via redeployment of brain areas,” “Circuit sharing and the implementation of intelligent systems,” “Investigating functional cooperation in the human brain using simple graph-theoretic methods,” “A self-help guide for autonomous systems,” and “Embodied cognition: A field guide.” Anderson was recently nominated for the Stanton Prize, recognized as an “emerging leader under 40” by the Renaissance Weekend, and was an invited participant in the McDonnell Project in Philosophy and the Neurosciences workshop for early career researchers.