ICCNS 2006 - Oral presentation

Learning and Cognitive Information Processing in Thalamocortical Assemblies:

Unifying Spikes, Synchronous Oscillations, and Resonance

M. Versace *; S. Grossberg +

Department of Cognitive and Neural Systems,

Center for Adaptive Systems, and

Center of Excellence for Learning in Education, Science, and Technology

Boston University, 02215 Boston, MA, USA

* versace@cns.bu.edu; + steve@cns.bu.edu (corresponding author)

A model of cortico-cortical and thalamo-cortical learning and information processing is developed to explicate the functional significance of higher-order specific thalamic nuclei as well as nonspecific thalamic nuclei, such as the midline and intralaminar nuclei. The model proposes how synchronization of neuronal spiking occurs within and across multiple brain regions and thalamic nuclei and simulates the functional link between spiking dynamics, synchronization and synaptic plasticity. The model is described in terms of spiking neurons that obey Hodgkin-Huxley type dynamics. Within this framework, the model shows how various operations from Adaptive Resonance Theory may control information processing and learning, notably the control of matching processes that can lead either to resonance and learning or to reset and memory search. The model functionally links data about cortical and thalamic neurophysiology and anatomy and single cell biophysics to functional properties such as resonance/learning, reset/search, top-down attention, and synchrony. In particular, the model simulates data on single cell biophysics, both cortical (Williams and Stuart, 1999; Saar et al, 2001; Larkum and Zhu, 2002) and subcortical (Sillito et al, 1994; Murphy et al, 1999; Jones, 2002; Crabtree and Isaac, 2002), and aggregate cell recordings (current-source densities and local field potentials; Kraus et al 1994; Heynen and Bear, 2001). It functionally links single cell and large-scale oscillations, notably in the gamma frequency band (Singer, 1990; Basar et al, 1991; Engel et al, 1991; Singer and Gray, 1995; Steriade and Amizca, 1996; Pantev, 1995; Miltner et al, 1999; Friedman-Hill et al, 2000), and clarifies the functional meaning of different oscillation frequencies.