Digital Commons Network^™

Hippocampal Theta And Gamma: Effects Of Aging, Environmental Change, Cholinergic Activation And Learning, Matthew D. Howe

Honors Scholar Theses

During aging, hippocampal functioning is impaired; specifically aged humans and rats show reduced performance on spatial memory tasks. An age-related reduction in the neurotransmitter acetylcholine has been postulated to underlie this impairment. Rhythmic oscillations (theta, gamma) may serve to synchronize activity within the hippocampus and across the brain during learning; these may also change with aging.

To determine what aspects of oscillation are important for memory processing, the effects of aging, encountering a novel situation, learning a new task and cholinergic system activation (with physostigmine) were examined. Both age groups showed increased theta, but not gamma activity when encoding a …