Persistent enhancement of basolateral amygdala-dorsomedial striatum synapses causes compulsive-like behaviors in mice (images)

Compulsive behaviors are observed in a range of psychiatric disorders, however the neural substrates underlying the behaviors are not clearly defined. Here we demonstrates the involvement of the BLA-DMS circuit in the emergence of enduring compulsive-like behaviors via its persistent synaptic changes. We revealed that the inputs from the BLA to the DMS are anatomically and functionally distinct from the BLA inputs to the nucleus accumbens (NAc). Furthermore, there is significant overlap between the BLA neurons projecting to the DMS and the neuronal population responsive to aversive stress. We also found that the BLA projections to the DMS are biased toward dopamine D1 receptor-expressing medium spiny neurons (D1-MSNs) compared to dopamine D2 receptor expressing neurons (D2-MSNs). Persistent molecular changes at the BLA-DMS synapses were observed in these mice and these changes were causally related to the compulsive-like phenotypes.