Work

Heightened Fear Memory Retention During Infancy, but Not Number of Separation‐Induced Ultrasonic Vocalizations, Predicts a Fearful Phenotype in a Diverse Cohort of Rats

Year: 2026

Type: article

Abstract: Past work using male rats, unexposed to early life adversity, suggests that number of separation-induced ultrasonic vocalizations (USVs) and retention of an aversive association during infancy predict later individual differences in fear behavior. The present study examined these associations using male and female rats that were either exposed or unexposed to early life adversity to test the generalizability of these findings. Separation-induced USVs were measured early in infancy. Animals were then subjected to Pavlovian fear conditioning later in infancy, and individual differences in retention were measured 6 days later. In adulthood, individual differences in learned (contextual fear conditioning) and innate fear (light-dark box performance) were assessed. Exploratory factor analysis revealed that these adulthood measures loaded onto a single factor (fearfulness). Heightened memory retention of an aversive association during infancy positively predicted adulthood fearfulness, but number of USVs emitted was not a significant predictor. Neither sex nor exposure to early life adversity affected the size, nor direction, of these relations. These results suggest that heightened fear memory retention during infancy is a better predictor of adulthood fearfulness than separation-induced USVs, and that these relationships generalize across sex and early life adversity exposure.

Source: Developmental Psychobiology

DOI: 10.1002/dev.70215

Authors: Sylvia K. Harmon‐Jones, Rick Richardson

Institutions: University of Wollongong, UNSW Sydney

Language: English

Topic: Memory and Neural Mechanisms

Subfield: Cognitive Neuroscience

Field: Neuroscience

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $3,760