Switching between Fear and Attraction Stephanie Moriceau, Donald A. Wilson, Seymour Levine, and Regina M. Sullivan
Neonatal rats learn rapidly to use odors to identify their mother. Pups are aided in this task by a boost in odor-preference learning and a deficit in odor-aversion learning, in a sensitive period before postnatal day 10 (P10). In this week's Journal, Moriceau et al. investigated the role of corticosterone (CORT) during the sensitive period. Rat pups that received a shock paired with odor at P8 learned an odor preference. However, systemic CORT injection 24 h and 30 min before pairing prematurely ended the sensitive period, resulting in odor aversion learning and activation of the amygdala. Conversely, removal of CORT by adrenalectomy prolonged the sensitive period. After adrenalectomy, P12 rats learned odor-shock preference rather than aversion and displayed increased olfactory bulb activity. The authors postulate that CORT acts as an amygdalar switch that favors the emergence of olfactory fear conditioning.

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News tips from the Journal of Neuroscience Stephanie Moriceau, Donald A. Wilson, Seymour Levine, and Regina M. Sullivan

Contact: Sara Harris

Society for Neuroscience