Repeated cocaine exposure induces lasting neurobehavioral adaptations such as cognitive decline in animal
models. However, persistent changes in spontaneous –unconditioned- motor and exploratory responses are
scarcely reported. In this study, mice were administered with cocaine (20 mg/kg/day) or vehicle for 12
consecutive days. After 24 days of drug abstinence, a behavioral assessment was carried out in drug-free conditions
and in unfamiliar environments (i.e. no cocaine-associated cues were presented). The cocaine-withdrawn
mice showed cognitive deficits in spontaneous alternation behavior and place recognition memory. Importantly,
they also displayed hyperlocomotion, increased rearing activity and altered exploratory patterns in different
tasks. In the forced swimming test, they were more active (struggled/climbed more) when trying to escape from
the water albeit showing normal immobility behavior. In conclusion, in addition to cognitive deficits, chronic
cocaine in rodents may induce long-lasting alterations in exploratory activity and psychomotor activation that
are triggered even in absence of drug-related stimuli.
