Figure 9.

High-frequency mPFC responses to the conditioned tone are reduced in MAM-treated rats. Multitaper spectral analyses of tone-evoked local field potential responses demonstrate that tone presentation alone induces a mild increase in prefrontal gamma (30–55 Hz) oscillations in saline (A), but not MAM (B), rats. Control rats that had received a mild footshock paired with a tone display a transient but significant increase in high-frequency activity evoked by the conditioned tone (C), that is attenuated in rats that had been exposed to the tone before the conditioning period (E). In contrast, MAM-treated rats did not display a robust response to the conditioned tone either in rats with (F) or without (D) previous tone exposure. The horizontal line depicts the 2 s tone presentation whereas the dashed line represents the control response (i.e., no tone presentation); n = 3–5 rats/group.