Dr. Jennifer Bizon

Assistant Professor
2008-2009 Montague Scholar
Ph.D., University of Califormia, Irvine (1998)

Department of Psychology
Texas A&M University
College Station, TX 77843-4235

Office: 256 Psychology Building
email: jbizon@tamu.edu
Phone: (979) 845-2506
Fax: (979) 845-4727
Web: http://neuroscience.tamu.edu

• Molecular and cellular mechanisms of age-related cognitive decline
• Neurogenesis and learning and memory
• Trophic factor localization and regulation
• Learning strategy across the lifespan

My research uses an integrative approach (a combination of behavioral and molecular assays) to investigate cognitive decline in aging. One line of this research utilizes a naturally occurring rodent model of age-related cognitive decline. Young and aged rats are characterized on a behavioral task that is sensitive to age-related impairment of the hippocampal/medial temporal lobe system. Just as in the human population, individual differences in memory abilities are present among these aged rats; about half of subjects perform on par with young adults whereas the rest perform outside this range, demonstrating impairment on the task. Using these behavioral indices, we are able to relate neurobiological changes in aging to the degree of memory impairment.

My most recent work using this aging model has examined the relationship between age-related changes in hippocampal neurogenesis and learning ability. We have recently discovered an unexpected correlation between higher numbers of recently generated neurons and worse cognitive performance among aged rats. Ongoing and future experiments are seeking to characterize the functional status of new neurons born in the aged brain and to determine if the role of adult generated neurons in learning changes across the lifespan.

A second line of research is based on recent findings from neuroimaging experiments in aged humans. These data show that old subjects who age successfully (i.e,, who maintain memory abilities on a level comparable to young adults) recruit different brain circuitry to encode new memories than do younger subjects. This finding suggests that the ability to accomplish new learning by flexibly engaging multiple or different brain systems may be more relevant to successful aging than maintaining the brain circuitry that is important for memory processes in young adults. We are currently exploring this idea in aged laboratory mice. Despite learning that is comparable to younger subjects, aged mice will choose a different strategy than younger subjects to complete a task when multiple approaches are equally effective. These data suggest that young and aged mice recruit different brain systems to accomplish the same task. Ongoing experiments are attempting to determine the relevant brain structures that underlie this age-related change in strategy and to determine the extent to which a shift in learning strategy during the lifespan contributes to successful cognitive aging.

R01 AG029421 8/1/07-6/30/12 $1,225,000.00
“Basal Forebrain and Cognitive Aging: Novel Experimental and Therapeutic Avenues”
Principal Investigator: Jennifer L. Bizon (35% effort)
National Institute of Aging

R01-DA13188 8/01/07-6/30/11 $1,000,000.00
“Heavy Metal and Drug Self-Administration: Mechanisms”
Co-Principal Investigator: Jennifer L. Bizon (15% effort)
National Institute of Drug Abuse, Jack Nation, PI

R01-AG07805 10/1/06-8/31 $900,000.00
“Physiology of cholinergic basal forebrain neurons”
Co-Principal investigator: Jennifer L. Bizon (15% effort),
National Institute of Aging, William H. Griffith, PI

Bizon, J.L., Gallagher, M. (2005) More is less: Neurogenesis and age-related cognitive decline in Long-Evans rats. Science Aging Knowledge Environment. Science. 16(7):re2.

Bizon, J. L., Prescott, S., & Nicolle, M. M. (2007). Intact spatial learning in adult Tg2576 mice. Neurobiol. Aging. 28(2): 440-6.

LaSarge, C.L., De Souza, K.A., Tucker, C., Slaton, S., Griffith, W.H., Setlow, B., & Bizon, J. L. (2007). Deficits across multiple cognitive domains in a subset of aged Fischer 344 rats. Neurobiol. .Aging, 28(6):928-36.

Bizon, J.L., LaSarge, C.L., Montgomery, K.A., McDermott, A.N., Setlow, B., & Griffith, W.G. (2007 Epub Ahead of Print). Reference and working memory across the lifespan of Fischer 344 rats. Neurobiol. Aging

Mendez, I.A., Montgomery, K.A., LaSarge, C.L., Simon, N.W., Bizon, J.L., & Setlow, B. (In Press). Long-term effects of cocaine exposure on spatial learning and memory. Neurobiol Learn Memory

Nicolle, M., Prescott, S., Bizon, J.L. (2003). Emergence of a cue strategy on the water maze task in aged B6XSJL F1 hybrid mice. Learn. Mem. 10 (6), 520-524.

Bizon, J. L., Gallagher, M. (2003). Production of new cells in the rat dentate gyrus over the lifespan: relation to cognitive decline. Eur. J. Neurosci, 18, 215-219.

Bizon, J. L., Han, J.-S., Hudon, C., Gallagher, M. (2003). Effects of hippocampal cholinergic deafferentation on learning strategy selection in a visible platform version of the water maze. Hippocampus. 13(6), 676-684.

Gallagher, M., Bizon, J. L, Hoyt, E.C., Helm, K.A., Lund, P. K. (2003). Effects of aging on the hippocampal formation in a naturally occurring animal model of mild cognitive impairment. Exp. Gerontol. 38(1-2), 71-77.

Bizon, J. L., Helm, K.A., Han, J.-S., Chun, H.-J., Pucilowski, J., Lund, P. K., Gallagher, M. (2001). Hypothalamic-pituitary-adrenal axis function and corticosterone receptor expression in behaviorally characterized young and aged rats. Eur. J. Neursci. 14, 1739-51.

Bizon, J. L., Lauterborn, J. Gall, C. (1999). Trophic Factors are expressed by distinct populations of striatal interneurons. J. Comp. Neurol., 408(2), 283-298.

Undergraduate:
PSYC 107 - Introductory Psychology

Link to Vita