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The amygdala is an almond-shaped region of the brain present in many vertebrates such as human, hamsters and mice. The amygdala is composed of several parts, of which the following are most relevant to my research: the basolateral amygdala (BLA) and the posterior medial amygdala (MeP). The BLA functions in learning and shows increased activation after the mouse has learned a behavior. The lateral paracapsular nuclei of the intercalated nucleus (ICNlpcn) project inhibitory neurons into the BLA and mediate its activity. Dopamine has been shown to inhibit the lpcn group and therefore relieve inhibition of the BLA (disinhibition). Dopamine also acts directly in the BLA to increase activation. Therefore, if a mouse is conditioned to prefer a particular odor (in this case steer urine), dopamine injection will cause an increase in BLA activation after learning due to both disinhibition and direct excitatory response. The medial posterior amygdala in the mouse mostly responds to olfactory stimuli from the same species (conspecific stimuli). The MeP is also thought to be under control of another ICN group, the caudal ICN (ICNc). If the same inhibitory relationship is seen between ICNc and MeP, the dopamine injection may cause disinhibition in the MeP and therefore the conditioned steer urine stimulus may show increased activation in the MeP despite being a stimulus from another species (heterospecific stimulus). My experiment tests whether the ICNc has inhibitory control over the MeP, and whether dopamine will cause inhibition in the ICNc and therefore cause disinhibition in the MeP.