Abstract
Environmental enrichment (EE) promotes resilience to stress, enhances cognitive abilities. While these impacts are strongly desirable, they must be balanced against the possibility that EE
increases behavioral variability in rodents (which would be a problem for our experiments). In
the taste system, EE leads to the attenuation of conditioned taste avoidance, but the effects of EE
on innocuous taste experience remain unknown. Here, we investigate how a playpen-style EE
impacts individual taste preferences (and variability therein). It was previously shown that rats
lacking EE exposure display variability in their individual taste preferences. We hypothesize that
enriched rats will consume unpalatable tastes more frequently than non-enriched controls as a
function of their reduced anxiety from EE. We also predict that EE may increase variability in
taste. We measure licking of enriched and non-enriched rats to a panel of tastes using the Brief
Access Task (BAT), evaluating their preferences as well as the inter- and intra-individual
variability. To verify the effectiveness of our EE protocol, we measure anxiety and exploratory
behavior in both groups using open field, novel object, and elevated maze tests; in addition, we
stain for brain-derived neurotrophic factor (BDNF) and doublecortin (DCX), both of which are
elevated in animals in enriched environments. Preliminary results using the open field test shows
a significant difference between anxiogenic unenriched and anxiolytic enriched animals, in
addition to clear trends in other measures of anxiety, suggesting that playpen EE successfully
reduces anxiety. Furthermore, this anxiety caused by a laboratory-based housing setup does not
interfere with taste preferences and variability: contrary to our initial hypothesis, EE not impact
individual taste preferences or the variability of taste preferences for each group of animals. In
addition to providing further insight into the impact of experience on taste, my results suggest