Transient and steady-state selection in the striatal microcircuit

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Adam Tomkins - , University of Sheffield (Author)
  • Eleni Vasilaki - , University of Sheffield (Author)
  • Christian Beste - , Department of Child and Adolescent Psychiatry and Psychotherapy, University Hospital Carl Gustav Carus Dresden (Author)
  • Kevin Gurney - , University of Sheffield (Author)
  • Mark D. Humphries - , University of Manchester (Author)

Abstract

Although the basal ganglia have been widely studied and implicated in signal processing and action selection, little information is known about the active role the striatal microcircuit plays in action selection in the basal ganglia-thalamo-cortical loops. To address this knowledge gap we use a large scale three dimensional spiking model of the striatum, combined with a rate coded model of the basal ganglia-thalamo-cortical loop, to asses the computational role the striatum plays in action selection. We identify a robust transient phenomena generated by the striatal microcircuit, which temporarily enhances the difference between two competing cortical inputs. We show that this transient is sufficient to modulate decision making in the basal ganglia-thalamo-cortical circuit. We also find that the transient selection originates from a novel adaptation effect in single striatal projection neurons, which is amenable to experimental testing. Finally, we compared transient selection with models implementing classical steady-state selection. We challenged both forms of model to account for recent reports of paradoxically enhanced response selection in Huntington's disease patients. We found that steady-state selection was uniformly impaired under all simulated Huntington's conditions, but transient selection was enhanced given a sufficient Huntington's-like increase in NMDA receptor sensitivity. Thus our models provide an intriguing hypothesis for the mechanisms underlying the paradoxical cognitive improvements in manifest Huntington's patients.

Details

Original languageEnglish
Article number192
JournalFrontiers in computational neuroscience
Volume7
Issue numberJAN
Publication statusPublished - 20 Jan 2014
Peer-reviewedYes

External IDs

ORCID /0000-0002-2989-9561/work/160952581

Keywords

Keywords

  • Action selection, Basal ganglia, Excitotoxicity, Huntington's disease, Response selection, Striatum