Transient and steady-state selection in the striatal microcircuit

Adam Tomkins, Eleni Vasilaki, Christian Beste, Kevin Gurney, Mark D. Humphries

    Research output: Contribution to journalArticlepeer-review

    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. © 2014 Tomkins, Vasilaki, Beste, Gurney and Humphries.
    Original languageEnglish
    Article number192
    JournalFrontiers in Computational Neuroscience
    DOIs
    Publication statusPublished - 20 Jan 2014

    Keywords

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

    Fingerprint

    Dive into the research topics of 'Transient and steady-state selection in the striatal microcircuit'. Together they form a unique fingerprint.

    Cite this