Figure 1.

A schematic view of SN and VTA connections. DA neurons receive input from the local GABA‐ergic interneurons and input from other brain areas. Both areas receive serotonergic input from the DEN. The dotted line indicates the subdivision of the SN: the SN pars reticulata (SN_r) and the SN pars compacta (SN_C). Neurons receiving a collective input are grouped (dotted circles). GABA‐ergic, glutamatergic and serotonergic inputs are indicated by black, white and gray symbols, respectively. HIPP, hippocampus; NAC, nucleus accumbens; PFC, prefrontal cortex; STN, subthalamic nucleus.