Format

Send to

Choose Destination
Cereb Cortex. 2014 Mar;24(3):677-90. doi: 10.1093/cercor/bhs348. Epub 2012 Nov 11.

Emergence of complex computational structures from chaotic neural networks through reward-modulated Hebbian learning.

Author information

1
Institute for Theoretical Computer Science, Graz University of Technology, Graz, Austria.

Abstract

This paper addresses the question how generic microcircuits of neurons in different parts of the cortex can attain and maintain different computational specializations. We show that if stochastic variations in the dynamics of local microcircuits are correlated with signals related to functional improvements of the brain (e.g. in the control of behavior), the computational operation of these microcircuits can become optimized for specific tasks such as the generation of specific periodic signals and task-dependent routing of information. Furthermore, we show that working memory can autonomously emerge through reward-modulated Hebbian learning, if needed for specific tasks. Altogether, our results suggest that reward-modulated synaptic plasticity can not only optimize the network parameters for specific computational tasks, but also initiate a functional rewiring that re-programs microcircuits, thereby generating diverse computational functions in different generic cortical microcircuits. On a more general level, this work provides a new perspective for a standard model for computations in generic cortical microcircuits (liquid computing model). It shows that the arguably most problematic assumption of this model, the postulate of a teacher that trains neural readouts through supervised learning, can be eliminated. We show that generic networks of neurons can learn numerous biologically relevant computations through trial and error.

KEYWORDS:

cortical microcircuit model; cortical plasticity; pattern generation; working memory

PMID:
23146969
DOI:
10.1093/cercor/bhs348
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Silverchair Information Systems
Loading ...
Support Center