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Show posters on the hill The Role of the Prefrontal Cortex and Amygdala in Trace and Contextual Fear Conditioning Mica Christensen, John Churchwell, Raymond Kesner Department of Psychology ^k The Role of the Prefrontal Cortex and Amygdala in Trace and Contextual Fear Conditioning Mica Christensen, John Churchwell, Raymond Kesner Department of Psychology A he goal of this study was to examine the role of the medial prefrontal cortex (mPFC) or the amygdala in fear conditioning. Two groups of animals were given chemical lesions to the amygdala, and mPFC while two control groups were given sham lesions to these regions (n=48). A third group of control animals with no lesions was also used. The animals with mPFC le- sions were run on fear conditioning trials which consisted of a 32 second (s) tone and then 10 s of a stimulus free period followed by a shock. The animals learned to associate the tone and shock as measured by freezing behavior. The following day the rats were placed into the same conditioning box for eight minutes during which time no tone was played and no shock was administered in order to test for retention of contextual learning. The third day, the rats were placed in a neutral box where the tone was played for 32 s followed by a 8s trace in order to test for retention of the tone response. The amount of freezing that occurred was coded in 8 s intervals. While the data has not been completed for the amygdala lesions, the mPFC lesions indicated that during acquisition the lesion animals were impaired for acquisition of the tone. There was no significant difference between the two groups in the trace and inter-trial intervals of acquisition. During retention there was no significant difference between the two groups to the tone. However, the results indicated that the mPFC lesions affected retention of the trace period. |