Current Research Areas
How does attention affect learning and
memory?
A network of cortical structures is thought to play a critical role in
regulating attention. Our current projects are examining how regions such
as the posterior parietal, frontal, cingulate, and retrosplenial cortices
influence neural activity in medial temporal lobe structures and affect
learning. These studies involve selective brain lesions and examining
neural activity by examining the expression of immediate-early genes.
Cortico-hippocampal
Systems in Learning and Memory
The hippocampus has a critical role in many forms of learning,
particularly those that involve the conjoining of multiple stimuli. However,
the hippocampus does not operate in a vacuum; cortical regions both
within and outside of the medial temporal lobe provide multi-sensory,
highly-processed information to the hippocampal formation. We are currently
studying how posterior cortical regions (e.g., posterior parietal cortex,
retrosplenial cortex) contribute to learning and memory, and whether they
contribute similarly, or have unique functions.
Nicotinic acetylcholine receptors in
attention & learning
Nicotinic acetylcholine
receptors are present in significant concentration in the hippocampus and
cerebral cortex. We are currently studying how these receptors modulate
learning that involves the inhibition of a behavioral response. In
addition, we are studying how kynurenic acid affects cognitive function;
kynurenic acid is an endogenous antagonist of nicotinic acetylcholine receptors
that is made by astrocytes, and is elevated in several different brain
disorders. Our ongoing studies are designed to provide insight into the function of nicotinic acetylcholine
receptors and also have implications for understanding the neural
basis of human disorders that involve deficits in inhibition (e.g., ADHD,
schizophrenia), and for understanding smoking behavior.
Effects of Physical Exercise on Learning and Memory
We are also interested in how physical exercise influences learning and memory that depend on the cortico-hippocampal circuits. Exercise is known to regulate neurogenesis in the hippocampus and increase levels of brain derived growth factor throughout the brain. Our studies are focused on understanding the temporal dynamics through which exercise affects learning and memory.
Sex Differences in Cognitive Function
Several studies are investigating the basis for sex difference in learning and attention, particularly related to animal models of ADHD. We are also examining how males and females respond to exercise and its effects on brain and behavior.