Abstract
A fear conditioning paradigm with rodents is commonly used to elucidate the neural fear mechanism in humans. One region that is suggested to be involved in detailed processing of stimuli during fear conditioning is the perirhinal cortex (PER). While the PER has previously been shown to be involved in fear conditioning to discontinuous, auditory stimuli, here, a discontinuous visual stimulus served as the conditioned stimulus (CS). Pre-training PER lesions (Lesion = 6, Sham = 7) and temporary PER inactivation (Muscimol = 6, Saline = 7) techniques were employed in rats to assess PER involvement in fear conditioning and, for the first time, fear extinction. Results showed that PER dysfunction impaired both fear conditioning and fear extinction to the CS (p < 0.05) as measured by freezing behavior. These findings offer a potential experimental design that could be employed in neurotranslational research that may allow for the assessment of PER function.