Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Mean ± SEM percentage of freezing during an 8 min extinction test in rats receiving sham surgery (SH) or neurotoxic basolateral amygdala lesions (BL) 1 week before training with either 1, 25, 50, or 75 unsignaled shocks. The extinction test was conducted 24 hr after training. Pretraining BLA lesions severely retarded the acquisition of contextual freezing, although normal asymptotic performance was achieved after 75 conditioning trials.
