Male rats with sexual experience present an inverse relation between theta activity and attention toward receptive females

Activity of the medial prefrontal cortex (mPFC) and nucleus accumbens (NAcc) during perception of sexual stimuli and states of sexual motivation are not yet well understood. This study explored the relation among electroencephalographic (EEG) activity, sexual experience, and attention in male rats during the detection of sexual stimuli while near a receptive female. Before and after three copulatory sessions until ejaculation, EEGs from the mPFC and NAcc of male rats were recorded while they were attentive to a receptive female but had no direct access to her. The sexually-experienced males displayed more attention responses and longer permanence near an inaccessible receptive female than the naïve rats. A lower power of the slow theta (4-7 Hz) band, but a higher power of the fast frequencies was observed in both the mPFC and NAcc of the sexually-experienced males in response to sexually-relevant stimuli compared to the naïve group. The correlation between the power of theta activity and attention parameters showed an inverse relation, indicating that once the males gained sexual experience, the longer duration of their nose pokes was related to a decrease in the RP of the 4-7 Hz band in both structures. It is likely that EEGs change in the theta range and fast frequences observed in the mPFC and NAcc reflect consolidation of the association between sexual stimuli and reward, thus facilitating adequate performance of the attentional and approach behaviors characteristic of sexual motivation.