The purpose of this grant proposal is to determine whether electrical stimulation of the amygdala could alter mnemonic information processing via a change in efficacy of specific neural transmitters (e.g., actylcholine dopamine, or norepinephrine). This will be accomplished using both electrical brain stimulation and intracranial chemical injection techniques. In addition, appropriate pharmacological, behavioral, degree of localization, and situational generality types of controls will be employed. It is hoped that this information will provide insights into the functional neural unit associated with mnemonic processing of information.