Home

About

Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network
FAQHELPSITE MAPCONTACT US


  Advanced Search  

 
A Neurobiological Theory of Automaticity in Perceptual Categorization F. Gregory Ashby, John M. Ennis, and Brian J. Spiering
 

Summary: A Neurobiological Theory of Automaticity in Perceptual Categorization
F. Gregory Ashby, John M. Ennis, and Brian J. Spiering
University of California, Santa Barbara
A biologically detailed computational model is described of how categorization judgments become automatic
in tasks that depend on procedural learning. The model assumes 2 neural pathways from sensory association
cortex to the premotor area that mediates response selection. A longer and slower path projects to the premotor
area via the striatum, globus pallidus, and thalamus. A faster, purely cortical path projects directly to the
premotor area. The model assumes that the subcortical path has greater neural plasticity because of a
dopamine-mediated learning signal from the substantia nigra. In contrast, the cortical-cortical path learns more
slowly via (dopamine independent) Hebbian learning. Because of its greater plasticity, early performance is
dominated by the subcortical path, but the development of automaticity is characterized by a transfer of control
to the faster cortical-cortical projection. The model, called SPEED (Subcortical Pathways Enable Expertise
Development), includes differential equations that describe activation in the relevant brain areas and difference
equations that describe the 2- and 3-factor learning. A variety of simulations are described, showing that the
model accounts for some classic single-cell recording and behavioral results.
Keywords: striatum, skill learning, habit learning, dopamine, expertise
Humans have a remarkable ability to categorize a huge number
of objects instantly and effortlessly. For example, when viewing a
German Shepard, we immediately respond dog rather than wolf,
even though such a categorization might require integrating per-

  

Source: Ashby, F. Gregory - Department of Psychology, University of California at Santa Barbara

 

Collections: Biology and Medicine; Computer Technologies and Information Sciences