Rats that underwent the CMS procedure were slower in gaining body weight and developed anxiety-like behavior, and there was a significant decrease in VTA DA neuron population activity. (A) CMS rats (n = 14) were significantly slower in gaining body weight compared to controls (CON; n = 14) (p < 0.05), and (B) developed anxiety-like behavior with less total time spent in the open arms (left) and fewer entries into the open arms (right) on the elevated plus maze (*, p < 0.05). (C) DA neuron population activity in CMS rats (n = 14, 80 neurons) was significantly lower than CON rats (n = 13, 134 neurons) (*, p < 0.05), with no significant differences in (D) mean firing rates or (E) bursting activity.