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INTRODUCTION: Dysfunction of the brain glutamatergic system is supposed to be one of fundamental causes underlying the schizophrenia. Administration of NMDA receptor antagonist (eg. MK801) leads to occurrence of various symptoms of that disease, inter alia, disruption of cognitive functions. AIM(S): The main aim of our study was to verify whether emotional/cognitive processes disturbed by local administration of MK801 into the basolateral amygdala (BLA) were associated with changes in electrical activity of two limbic structures: BLA and nucleus accumbens (NAc). METHOD(S): Experiments were done according to a classical fear conditioning paradigm. During consecutive sessions we recorded Local Field Potentials (LFPs) and videotaped the behavior of animals. Three experiments were performed: A) control (no pharmacological intervention), B) with MK801 infusion into BLA and C) with MK801 infusion and clozapine injection (i.p.). In experiments B and C animals were divided into two groups: drugs were administered 1) before acquisition sessions or 2) before first three extinction sessions. Power spectra were calculated for frequency bands: delta, theta, beta 1, beta 2, low gamma and high gamma during freezing and non-freezing behaviour for two time segments: during and after conditioned stimulus presentation. RESULTS: Analysis of data revealed that in experiment (BII) MK801 infusion disrupted extinction process. In experiment (CII) clozapine did not influence the delayed extinction of conditioned response. Most differences between band powers were found for theta, beta 1 and 2 bands, with increase in power in consecutive sessions in both experiments (A, B). In experiment C the greatest power was observed in sessions with clozapine. CONCLUSIONS: The same behavior (freezing) was associated by various patterns of differences between power spectra. The increasing power of theta, beta 1 and 2 bands in experiments A and B may indicate increasing level of attention. FINANCIAL SUPPORT: Funding: the National Center of Science (Poland) DEC-2011/03/B/NZ4/03768.