[Abstract Title]. - Society for Neuroscience

Poster
295. Memory Consolidation, Reconsolidation, Anatomy, and Mechanisms
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 295.15/SS65
Topic: F.02.h. Memory modulation, consolidation, and reconsolidation
Support: Research supported by the School of Behavioral and Brain Sciences at the University
of Texas at Dallas
Title: Environmentally induced modification of the long term consolidation process of
contextual fear memory
Authors: *D. F. PENA, V. C. ROBERTS, K. CHANG, M. P. KILGARD, C. K. MCINTYRE;
Univ. of Texas at Dallas, Richardson, TX
Abstract: Environmental enrichment (EE) refers to a housing regimen that, relative to standard
housing, has larger cages, activity-related toys, more conditions or states in which to learn, and
greater social complexity. Early findings showing marked increases in cortical thickness in the
occipital cortices and increased dendritic spine densities were the first to demonstrate that an
enriched environment could affect plastic changes in the brain. Current research suggests that EE
leads to behavioral, cellular and molecular changes. Recent work by Fischer and colleagues
suggests that prolonged enrichment can recover previously unrecoverable memories in CK-p25
transgenic mice. However, little is known about the effects of enrichment on loss and recovery of
memories in normally functioning animals. Here we examined the effects of enrichment on
acquisition and memory retention performance 2 days and 2 weeks after a single training
experience. Female Sprague-Dawley rats were housed on a reverse night/day cycle in one of two
paradigms for 30 days. Enriched animals were communally housed (6 rats/cage) in a large (76 L
x 45 W x 90 H cm) cage with a running wheel and several forms of auditory stimulation. Control
animals were individually housed (25 L x 15 W x18 H) in a 30 cage colony rack. All animals
were subsequently trained on a continuous multi-trial inhibitory avoidance task. Memory
retention was tested 2 days and again 2 weeks after training. Enriched animals did not
differentially acquire the task (p>0.9), nor did they perform significantly better in a retention test
2 days post training (p > 0.5). However, retention latency was reduced after 2 weeks in nonenriched
animals, but it was increased in enriched animals. A within animal retention
comparison (2 wks/2 days) showed a significant difference in performance between enriched and
non-enriched animals (p