Studies of learning and memory are often performed using young adult animals as laboratory models of human learning. These investigations, however, do not address one of the major factors influencing memory: Aging. Dr. Gallagher's research focuses on providing a more complete description of learning ability in animals toward the end of their normal lifespan. Rodents are the ideal subjects in which to study age-related memory changes, because we can observe mild-to-severe memory impairments over the relatively short period (in human terms) of two to three years. In her previous work, Dr. Gallagher has developed a series of memory tests which clearly expose performance differences between young and aged animals. These tests, furthermore, are capable of distinguishing those behaviors which depend upon the integrity of certain identified brain regions, and those which do not. Dr. Gallagher will conduct several experiments to extend these findings, and will begin examining the extent to which each of these behavioral tasks depends upon a specific neurotransmitter system (acetylcholine) being intact. Specifically, she will determine the relationship between changes in behavioral capacities and the effects of training on acetylcholine function in aged animals. These results will address the hypothesis that altered learning and memory function in normal aging animals is associated with a change in the functional status of the basal forebrain cholinergic system. Knowledge about relationships between learning and memory and the status of a specific brain system during aging will provide a more complete understanding of progressive memorial deficits occurring over the lifespan.
