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Peak, J.

Publications and source records attributed to Peak, J..

2 recordsLinked to original sources

Intratelencephalic neurons in the medial prefrontal cortex mediate the acquisition of goal-directed actions.

The medial prefrontal cortex (mPFC) and its connections with the posterior dorsomedial striatum are implicated in goal-directed learning, but the specific mPFC cell types involved have not been clearly established. The current study investigated mPFC intratelencephalic (IT) and pyramidal tract (PT) neuron involvement in goal-directed learning. In Cre-driver mouse lines, we mapped bilaterally projecting IT neurons and unilaterally projecting PT neurons from mPFC to dorsal striatum and showed that chemogenetic inhibition of IT, but not PT neurons, attenuated goal-directed learning. We then demonstrated training induced elevations in pERK signaling in IT neurons, which were transient in superficial mPFC layers, and more persistent in deeper layers. This was associated with plasticity in deep layer IT neurons, reflected in a shift towards excitatory over inhibitory synaptic inputs. Together, these data suggest that goal-directed learning influences synaptic input and downstream plasticity markers in mPFC IT neurons, and this functionally contributes to goal-directed learning.

neuroscience↗

Striatal direct and indirect pathway neurons differentially control the encoding and updating of goal-directed learning.

The posterior dorsomedial striatum (pDMS) is necessary for goal-directed action, however the role of the direct (dSPN) and indirect (iSPN) spiny projection neurons in the pDMS in such action remains unclear. In this series of experiments, we examined the role of pDMS SPNs in goal-directed action and found that, whereas dSPNs were critical for goal-directed learning and for energizing the learned response, iSPNs were involved in updating that learning to support response flexibility. Instrumental training elevated expression of the plasticity marker Zif268 in dSPNs only, and chemogenetic suppression of dSPN activity during training prevented goal-directed learning. Unilateral optogenetic inhibition of dSPNs induced an ipsilateral response bias in goal-directed action performance. In contrast, although initial goal-directed learning was unaffected by iSPN manipulations, optogenetic inhibition of iSPNs, but not dSPNs, impaired the updating of this learning and attenuated response flexibility after changes in the action-outcome contingency.

neuroscience↗