Background: The amygdala is one of the nerve centers involved in drug reward. It is suggested that the central nucleus of the amygdala (CeA) is involved in morphine dependency. The CeA gamma-aminobutyric acid-ergic (GABAergic) system is a mediator of morphine rewarding effects. In this research, the effects of stimulation or inhibition of CeA GABA type B (GABAB) receptors on sensitization acqui...

Amphetamine use is associated with dysphoric states, including heightened anxiety, that emerge within 24h of withdrawal from the drug. Corticotropin-releasing factor increases serotonin release in the central nucleus of the amygdala, and this neurochemical circuitry may play a role in mediating fear and anxiety states. We have previously shown that chronic amphetamine treatment increases cortic...

Animals learn to avoid harmful situations by associating a neutral stimulus with a painful one, resulting in a stable threat memory. In mammals, this form of learning requires the amygdala. Although pain is the main driver of aversive learning, the mechanism that transmits pain signals to the amygdala is not well resolved. Here, we show that neurons expressing calcitonin gene-related peptide (C...

Conditioned taste aversion (CTA) is acquired when the ingestion of a food is followed by malaise. CTA is a kind of fear learning making animals avoid subsequent intake of the food and show aversive behavior to the taste of the food. To elucidate the brain regions responsible for the expression of CTA, our previous electrophysiological and recent c-fos immunohistochemical studies have been revie...

Objective(s) The central nucleus of the amygdala (CeA) is a forebrain structure which is important in regulation of ingestive behavior and there is direct and circumstantial evidence to indicate that some circuits involved with feeding behavior include glutamatergic elements. The present study examined whether administration of NMA (N-Methyl-DL-aspartic acid) or MK801 into the CeA altered wate...

Rorick-Kehn and Steinmetz (2005) report that neurons in the central and basolateral nuclei of the amygdala exhibit learning-related spike firing to conditional stimuli associated with shock in 3 different aversive conditioning paradigms: eyeblink conditioning, fear conditioning, and signaled avoidance conditioning. Central nucleus neurons responded in all 3 tasks, whereas basolateral nucleus ne...

The amplitude of the acoustic startle response is reliably enhanced when elicited in the presence of bright light (light-enhanced startle) or in the presence of cues previously paired with shock (fear-potentiated startle). Light-enhanced startle appears to reflect an unconditioned response to an anxiogenic stimulus, whereas fear-potentiated startle reflects a conditioned response to a fear-elic...