Karyn Frick, Yale Psychology Faculty

The primary focus of my research is to understand how aging affects memory and the brain, and to develop therapeutic strategies (both pharmacological and behavioral) to reduce age-related memory decline. To this end, we study the roles that neurochemical and hormonal alterations of the hippocampus and neocortex play in age-related mnemonic dysfunction and attempt to enhance mnemonic function by augmenting the function of these brain regions. By studying how aging affects the neurobiology of learning and memory in a model system such as the rodent, we can better understand how aging alters these processes in humans and develop effective therapeutic treatments. Towards this goal, we utilize a variety of methods including behavioral, pharmacological, and transgenic techniques.

We have discovered, for example, that spatial memory deteriorates in female mice at an earlier age than in males. This decline in females may be linked to age-related reductions of estrogen and progesterone, and we have found that estrogen replacement can improve memory in aging females. We have also found that environmental enrichment improves memory in aging male and female mice. Both of these treatments alter key synaptic proteins in the hippocampus and neocortex, suggesting that these treatments enhance memory by augmenting synaptic plasticity. In young female mice, we have found that estrogen can enhance memory consolidation, but that this effect is reduced by prior environmental enrichment.

Our other research projects involve investigating the abilities of estrogen and progesterone to alter memory in young and older females, identifying sex and species differences in behavior and neurochemistry, examining the role of basal forebrain cholinergic neurons in learning and memory, and employing transgenic mouse models to delineate the underlying causes of Alzheimer's disease.

Sample Publications

Harburger, L.L., Bennett, J.C., and Frick K.M. Effects of estrogen and progesterone on spatial memory consolidation in aged females. Neurobiology of Aging, in press.

Gresack, J.E. and Frick, K.M. (2006). Post-training estrogen enhances spatial and object memory consolidation in female mice. Pharmacology Biochemistry and Behavior, 84(1), 112-119.

Bennett, J.C., McRae, P., Levy, L.J., and Frick K.M. (2006). Long-term continuous, but not daily, environmental enrichment reduces spatial memory decline in aged male mice. Neurobiology of Learning and Memory, 85, 139-152.

Levy, L.J., Astur, R.S., and Frick K.M. (2005). Men and women differ in object memory, but not performance of a virtual radial maze. Behavioral Neuroscience, 119(4), 853-862.

Gresack, J.E. and Frick, K.M. (2004). Environmental enrichment reduces the mnemonic and neural benefits of estrogen. Neuroscience, 128(3), 459-471.