Figure 1.

Effects of sex and stress on acquisition of the conditioned eyeblink response. (A) In males, exposure to the stressor facilitated acquisition of the CR 24 h after stressor cessation. (B) In females, exposure to the same stressor impaired acquisition of the CR 24 h after stressor cessation. Unstressed females elicited more CRs than unstressed males during the first day of training (1–300 trials), but were not significantly different from each other by the second day of training (301–600 trials). Spontaneous (SPON) eyeblink activity was not affected by sex.