Seminars & Events
Friday, October 4, 2013: Dr. Laurie Ryan, SMCM '86 (National Institute on Aging) will speak on "Alzheimer's Disease: Targets and Treatments" at 3:00 pm in Goodpaster Hall 195.
Monday, October 21, 2013: Dr. Greg Elmer (University of Maryland Baltimore) will speak on "Domains and Constructs in Motivation: Where Does the Habenula Fit In?" at 4:45 pm in Goodpaster Hall 195.
Friday, October 25, 2013: Dr. Terry Davidson (American University) will speak on "Why We Overeat and Become Obese? It Could be What We Think!" at 3:00 pm in Goodpaster Hall 195.
Dr. Gwen Calhoon '06 recently received her Ph.D. in Neuroscience from the University of Maryland Baltimore, and was inducted into Nu Rho Psi.
Bailey, A.M., Holmes, A., and Piantadosi, P. (2011, November). The effects of orexin A in the nucleus basalis magnocellularis (nBM) on olfactory discrimination acquisition and reversal
Poster presented at the Society for Neuroscience Annual Meeting, Washington, DC.
Alzheimer’s disease (AD) is characterized by hypofunction of the basal forebrain cholinergic system, which results in memory and attentional deficits observed in individuals suffering from the disease. Progressive neurodegeneration renders the primary source of cortical acetylcholine (ACh), the nucleus basalis magnocellularis (nBM), unable to innervate the cortex at normal physiological levels. Recent research has implicated a group of hypothalamic neuropeptides, the orexins (orexin A and B, also known as hypocretin 1 and 2), in aiding in the efflux of endogenous ACh from the nBM to the cortex. Microdialysis administration of orexin A (OxA) to the nBM in rats has previously been shown to stimulate cortical ACh release. We tested the direct effects of intrabasalis OxA infusion on acquisition and reversal of an olfactory discrimination task. To further examine the effect of OxA on attention, some of the animals were exposed to a background irrelevant odor to increase the attentional demand of the task. Animals given infusions of OxA required significantly fewer trials to criterion (p < 0.01) and a decreased number of errors (p = 0.09) on the original olfactory discrimination problem. The background scent did not alter performance during acquisition. OxA also significantly lowered the number of trials to criterion (p < 0.001) and the number of errors (p < 0.001) on the discrimination reversal problem. There was a near significant interaction (p = 0.059) between the drug infused (OxA or aCSF) and the background odor (present or not). Animals infused with aCSF showed an increased number of errors during reversal when the background scent was present, while animals infused with OxA did not show a change in the number of errors with the distracting odor. Our results demonstrate enhanced discrimination in both the acquisition and reversal of an olfactory discrimination task with direct infusion of OxA in the nBM.