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.
CPFE fear conditioning across the life span. Percentage of time freezing during pre-exposure (Phase 1) and context test (Phase 3) in mice aged 4–25 months is shown. 25 month-old mice froze significantly more during the initial five minute pre-exposure, but no differences were found during the six minute context test.
