Figure 1.

A, Training procedure for the 3-day muscimol and 3-day saline groups. Phase 1 consisted of four daily sessions of paired tone-air puff acquisition training. Phase 2 consisted of three tone-alone extinction sessions. One hour before each of these sessions, muscimol or saline was infused into the motor nuclei. Phase 3 consisted of four more tone-alone extinction sessions. No infusions were administered during these sessions. Phase 4 consisted of one session of paired tone-air puff reacquisition training. B, Training procedure for the 6-day muscimol and 6-day saline groups. Each of the four phases of training were the same as above, except that rabbits received six extinction sessions with infusions during phase 2.