Controlling the Go/No-go decision threshold in striatum
by
Jyotika Bahuguna(CB, KTH and Bernstein Center Freiburg)
→
Europe/Stockholm
RB35
RB35
Description
A typical Go/No-Go decision is thought to be implemented via the activation of direct or indirect pathway
in the basal ganglia. Striatal neurons participating in these two pathways express D1 and D2 type
dopamine receptors. Recent evidence has shown specific recurrent connectivity and passive properties
of these two types of striatal neurons. To understand the striatal function, it is therefore important to
identify factors that regulate the balance of activity in D1 and D2 MSNs. Here we used both, a reduced
firing rate model and numerical simulations of the striatal networks to analyze the dynamic balance of
spiking activity in D1 and D2 MSNs. This analysis revealed many integral insights, most important
being the possible presence of a decision threshold in striatum controlling the bias towards a Go/No-Go
response to the cortical input. It also suggests that this threshold could be influenced by many factors,
including the activity of FSI (Fast Spiking Interneurons), levels of dopamine, the STN-GPe circuit and
input correlations in the cortical input, thereby providing different possible mechanisms to bias the basal
ganglia output either in the favour of Go pathway or the No-Go pathway. The model also suggests
possible explanations for various phenomological observations during Parkinson’s disease like increased
reaction times, L-Dopa Induced Dyskinesia and DBS induced impulsivity
