A single dose of ethanol in adult mice transiently alters the organization of spontaneous exploratory behaviors in a dark open field.

Acute exposure to ethanol is known to produce significant alterations to the functions of the hippocampus leading to "blackouts" which are defined as temporary disruptions to the encoding and retention of memories. The hippocampus has a prominent role in generating representations of spatial location and contributes to spatial navigation. In open environments, spatial exploratory behaviors are organized such that animals spontaneously alternate between long duration stops (absence of movement) at a specific home base location and exploratory trips or progressions (locomotion between locations) into the remaining environment. Open field exploratory behaviors are organized even in darkness, suggesting a contribution of self-motion cues (e.g., vestibular) to spatial behavior. In the present study, we tested the hypothesis that acute single-dose ethanol exposure in adult mice would disrupt the expression of organized exploratory behaviors in an open field under darkened conditions. Male and female adult mice received a single injection of ethanol and explored a dark environment (under infrared light) for 30 min. Mice tested immediately after the injection exhibited reductions in locomotion and spontaneous behavior, while those tested 30 min later only exhibited suppressed locomotion. These results suggest that ethanol exposure leads to alterations in spontaneous exploratory behaviors.