Abstract
It is thought that Pavlovian fear conditioning with electric shocks as unconditioned stimulus is an effective procedure to elucidate the neural substrates of learning and memory. In this paper, we start with a brief review on neural pathways of fear conditioning with an auditory or visual conditioned stimulus. Next, focusing on the amygdala that plays an critical role in these pathways, we present our experiment, in which we studied the role of subdivision of the amygdala in fear conditioning. As a result, it was obvious that two different neural pathways mediated the informations about input of the two conditioned stimulus; auditory and visual ones respectively, even if the same unconditioned stimulus; electric shock was used. Finally, we describe the future direction of the researches on this topic.
