The auditory cortex is involved in encoding sounds which have acquired an emotional-motivational charge. However, the neural circuitry engaged by emotional memory processes in the auditory cortex is poorly understood. In this study, we investigated the layers and regions that are recruited in the higher order auditory cortex Te2 by a tone previously paired to either fear or appetitive stimuli in rats. By tracking the protein coded by the immediate early gene zif268, we found that fear memory

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... rieval engages layers II-III in most regions of Te2. These results were neither due to an enhanced fear state nor to fear-evoked motor responses, as they were absent in animals retrieving an olfactory fear memory. These layers were also activated by appetitive auditory memory retrieval. Strikingly, layer IV was recruited by fear, but not appetitive memories, whereas layer V activity was related to the behavioral responses displayed to the CS. In addition to revealing the layers and regions which are recruited in the Te2 by either fear or appetitive remote memories, our study also shows that the neural circuitry within the Te2 that processes and stores emotional memories varies on the basis of the affective-motivational charge of tones. Analysis of immediate early gene expression The order of sections was reconfirmed under the microscope and each section was assigned to a corresponding range in the antero-to-posterior (AP) coordinates to the bregma, based on the Paxinos and Watson atlas (Paxinos and Watson 1986). The higher order auditory Te2 cortex was defined on the basis of the Paxinos and Watson atlas, with cortical fields referenced to the Zilles atlas (Zilles 1985) . The AP distance between consecutive sections was 50 µm. The analyzed area covered the