Impairment of cingulothalamic learning-related neuronal coding in rabbits exposed to cocaine in utero: General and sex-specific effects

Neuronal activity was recorded in the cingulate cortex and the limbic thala mus in Dutch-belted rabbits (Oryctolagus cuniculus) exposed to cocaine (8 m g/kg/day iv) or saline in utero during acquisition and reversal learning of a discriminative avoidance response. Anterior cingulate cortical excitator y training-induced activity (TIA) was attenuated in cocaine-exposed female rabbits during acquisition and reversal learning, but only during reversal learning in male rabbits. Posterior cingulate cortical excitatory TIA was l essened in cocaine-exposed rabbits during acquisition, whereas discriminati on between the positive and negative cues was enhanced. Neuronal firing was attenuated in the anterior ventral thalamus in cocaine-exposed rabbits dur ing acquisition and reversal learning. Behavioral learning was normal in co caine-exposed rabbits. Other data suggest that rabbits exposed to cocaine i n utero exhibit a learning deficit when trained with nonsalient cues.