Fig. 2
From: Previous cocaine self-administration disrupts reward expectancy encoding in ventral striatum
Previous cocaine-exposure diminishes value and directional encoding in NAc. a Single neuron example during long-delay (left panel) and short-delay trials (right panel). Activity is aligned to reward delivery (marked by arrows) and binned at 100 ms. One tick mark equals one action potential. b, c Population activity for responsive neurons in control rats (n = 195; 6 rats) during the last ten trials for each outcome. b Normalized firing rates for neurons in the preferred direction (direction that elicited the most activity). c Normalized firing rates for neurons in the non-preferred direction. Figure includes both forced and free-choice trials. Blue lines are short-delay trials, red lines are long-delay trials, green lines are large-reward trials, and yellow lines are small-reward trials. Activity is aligned to fluid-well entry for short, big and small trials (reward occurred 500 ms later; dashed gray line). For long-delay trials activity is split, aligned to “Well Entry” and “Reward Delivery”. d, e Same as c–b but for neurons (n = 103; 4 rats) collected from rats that had self-administered cocaine
