RT Journal Article
SR Electronic
T1 Choice-selective sequences dominate in cortical relative to thalamic inputs to nucleus accumbens, providing a potential substrate for credit assignment
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 725382
DO 10.1101/725382
A1 Nathan F. Parker
A1 Avinash Baidya
A1 Julia Cox
A1 Laura Haetzel
A1 Anna Zhukovskaya
A1 Malavika Murugan
A1 Ben Engelhard
A1 Mark S. Goldman
A1 Ilana B. Witten
YR 2021
UL http://biorxiv.org/content/early/2021/09/02/725382.abstract
AB How are actions linked with subsequent outcomes to guide choices? The nucleus accumbens, which is implicated in this process, receives glutamatergic inputs from the prelimbic cortex and midline regions of the thalamus. However, little is known about whether and how representations differ across these input pathways. By comparing these inputs during a reinforcement learning task in mice, we discovered that prelimbic cortical inputs preferentially represent actions and choices, whereas midline thalamic inputs preferentially represent cues. Choice-selective activity in the prelimbic cortical inputs is organized in sequences that persist beyond the outcome. Through computational modeling, we demonstrate that these sequences can support the neural implementation of reinforcement learning algorithms, both in a circuit model based on synaptic plasticity, and one based on neural dynamics. Finally, we test and confirm predictions of our circuit models by direct manipulation of nucleus accumbens input neurons. Thus, we integrate experiment and modeling to suggest neural solutions for credit assignment.Competing Interest StatementThe authors have declared no competing interest.