Cholinergic Interneurons Provide a Link to Balance Excitation across Striatal Output Neurons

D1-MSNs and D2-MSNs mediate output from the accumbens. How activity of one regulates the other is poorly understood. In this issue of Neuron, Francis et al. (2019) show that D1-MSN firing induces D2-MSN LTP via the recruitment of cholinergic interneurons.