Seminars & Events
Thursday, September 11, 2014: Dr. Bevil Conway (Wellesley College) will speak on his research in visual neuroscience and color at 4:30 pm in Goodpaster Hall 195.
Monday, October 27, 2014: Dr. Todd Gould (University of Maryland Baltimore) will speak on "Genes to behaviors to treatments in bipolar disorder" at 4:45 pm in Goodpaster Hall 195.Friday, December 5, 2014: Dr. Brian Mathur (University of Maryland Baltimore) will speak on "Braking bad: Aberrant inhibitory neurotransmission in addiction" at 3:00 pm in Goodpaster Hall 195.
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.