Manipulating the revision of reward value during the intertrial interval increases sign tracking and dopamine release
Fig 3
Development of sign tracking and DA signals over training.
(A-B) Average beam break (solid) and lever press (dashed) rate for 120-s (A) and 60-s (B) ITI sessions. (C-D) Average lever press rate for 120-s (C) and 60-s (D) ITI sessions. Percentages for each session were computed and then averaged across sessions. Data are the same as in A and B but with a smaller scale so that differences and timing can be better visualized. (E-F) Average DA release over time for 120-s (E) and 60-s (F) ITI sessions. In each of the above (A-F), data are broken down into averages from sessions 1–3 (pale colors, pink [120 s] and turquoise [60s]) and sessions 4–10 (dark colors, red [120 s] and blue [60 s]); 60-s ITI group = 7 rats; 120-s ITI group = 12 rats. DA release for each session was computed and then averaged across sessions. For analysis averaged within session and rat and then averaged across rat, please see S2 Fig. (G-H) Average DA release over time for each of the 10 sessions for the 120-s ITI group (G) and the 60-s ITI group (H). For breakdown of behavior by session for each of the 10 sessions, please see S4 Fig. (I-J) Average DA release over time for 120-s (I) and 60-s (J) ITI groups broken down into sessions in which rats either lever pressed (120-s ITI = 4 rats, 20 sessions; 60-s ITI = 2 rats, 7 sessions) or entered the food cup during the CS (120-s ITI = 3 rats, 13 sessions; 60-s ITI = 4 rats, 18 sessions). Error bars represent SEM. Underlying data for Fig 3 can be found in S3 Data. CS, conditioned stimulus; DA, dopamine; GT, goal tracking; ITI, intertrial interval; ST, sign tracking; US, unconditioned stimulus.