Dopamine signaling is implicated in reinforcement learning, but the neural substrates targeted by dopamine are poorly understood. We bypassed dopamine signaling itself and tested how optogenetic activation of dopamine D1 or D2 receptor-expressing striatal

We show that a natural behavior, exploration of a novel environment, causes DNA double-strand breaks (DSBs) in neurons of young adult wild-type mice. DSBs occurred in multiple brain regions, were most abundant in the dentate gyrus, which is involved in lea