Fig. 2. Cocaine place conditioning modulates Tac2 neuronal activities that are associated with cocaine reward contexts.

(A) Diagrammatic illustration of the calcium imaging recording experiment during pre– and post–cocaine place conditioning. “S,” conditioning with saline injection; “C,” conditioning with cocaine injection. (B) Bar graph showing the time spent in cocaine chamber during pre– and post–cocaine place conditioning. (C) Top: Representative calcium transients of neurons from one mouse during staying in saline (S)– or cocaine (C)–coupled chambers. Both the cocaine chamber–excited neurons (orange) and cocaine chamber–inhibited neurons (blue) are shown. Bottom: Average calcium traces of the above cocaine chamber–excited neurons (orange) and cocaine chamber–inhibited neurons (blue). (D) Top: Pie chart showing the fraction of cells that were excited by (orange), inhibited by (blue), or had no response to (gray) staying in a cocaine-associated chamber during preconditioning (left) or postconditioning (right). Bottom: Bar graphs showing the percentage of neurons that were excited (orange) or inhibited (blue) when staying in a cocaine-associated chamber. (E) Calcium transient frequency of cocaine chamber–excited neurons (left, n = 16) and cocaine chamber–inhibited neurons (right, n = 62) during mice staying in saline or cocaine chambers. (F) Left: Average calcium transient frequency of cocaine chamber–excited neurons before and after entering cocaine chamber. Right: Quantification of calcium transient frequency in 5-s windows before and after entry. (G) Left: Average calcium transient frequency of cocaine chamber–inhibited neurons before and after entering cocaine chamber. Right: Quantification of calcium transient frequency in 5-s windows before and after entry. Data in (B), (D), (G), and (H) are presented as means ± SEM; shaded areas in (C) represent SEM. The P values are calculated on the basis of statistical tests in table S1. **P ≤ 0.01; ****P ≤ 0.0001; ns, P > 0.05.