University of Vermont

The College of Arts and Sciences

Department of Psychological Science

Hammack Laboratory of Behavioral Neuroscience

Research in the Hammack laboratory examines the neurobiology of emotion and emotional learning, with a particular interest in the role of peptide systems and serotonin in the regulation of fear and anxiety behavior. We are also interested in factors that determine the behavioral consequences of exposure to stressful or threatening stimuli, such as controllability and exercise, and the brain mechanisms by which these treatments alter behavior.

Principal Investigator

Graduate Students

Samamwong 'Jom' Hammack

Samamwong "Jom" Hammack, Ph.D.

Associate Professor of Psychological Science
Olivia Miles

Olivia Miles, B.S.

Bradley King

Bradley King, B.S.

Post-Doctoral Fellow

Kimberly Lezak

Kimberly Lezak, Ph.D.

Selected Publications

  • Lezak, K.R., Roelke, E., Harris, O., Choi, I., Edwards, S., Gick, N., Cocchiaro, G., Missig, G., Roman, C.W., Braas, K.M., Toufexis, D.J., May, V., Hammack, S.E., (2014) Pituitary adenylyl cyclase activating peptide (PACAP) in the bed nucleus of the stria terminalis (BNST) increases corticosterone in male and female rats, Psychoneuroendocrinology, in press.
  • Lezak, K.R., Roman, C.W., Braas, K.M., Schutz, K.C., Falls, W.A., Schulkin, J., May, V., Hammack, S.E., (2014) Regulation of bed nucleus of the stria terminalis PACAP expression by stress and corticosterone, Journal of Molecular Neuroscience, in press.
  • Kocho-Schellenberg, M., Lezak, K.R., Harris, O.M, Roelke E., Gick, N., Choi, I., Edwards, S., Wasserman, E., Toufexis, D.J., Braas, K.M., May, V., Hammack, S.E., (2014) Pituitary adenylate cyclase activating peptide (PACAP) in the bed nucleus of the stria terminalis (BNST) produces anorexia and weight loss in male and female rats, Neuropsychopharmacology, in press.
  • Hare, B.D., Beierle, J., Toufexis, D.T., Hammack, S.E., Falls, W.A., (2013) Exercise associated changes in the corticosterone response to acute restraint stress: evidence for increased adrenal sensitivity and reduced corticosterone response duration, Neuropsychopharmacology, in press.
  • Hare, B.D., D’Onfro, K.C., Hammack, S.E., Falls, W.A., (2012) Prior stress interferes with the anxiolytic effect of exercise in C57BL/6J mice, Behavioral Neuroscience, 123(6): 850-6.
  • Roman, C.W., Lezak, K.R., Kocho-Schellenberg, M., Garret, M., Braas, K., May, V., Hammack, S.E., (2012). Excitotoxic lesions of the bed nucleus of the stria terminalis (BNST) attenuate the effects of repeated stress on weight gain: Evidence for the recruitment of BNST activity by repeated, but not acute, stress, Behavioural Brain Research, 227(1): 300-4.
  • Hammack, S.E., Cooper, M.A., Lezak, K.R., (2012) Overlapping neurobiology of learned helplessness and conditioned defeat: Implications for PTSD and mood disorders, Neuropharmacology, 62(2):565-75.
  • Ressler, K.J., Mercer, K.B., Bradley, B., Jovanovic, T., Mahan, A., Kerley, K., Norrholm, S.D., Kilaru, V., Smith, A.K., Myers, A.J., Ramirez, M., Engel, A., Hammack., S.E., Toufexis, D., Braas, K.M., Binder, E.B., May, V. (2011) PTSD is associated with the PAC1 receptor and dysregulation of PACAP, Nature, 470: 492-497.
  • Hammack, S.E., Roman, C.W., Lezak, K.R., Kocho-Schellenberg, M., Grimmig, B., Falls, W.A., Braas, K., May, V. (2010) Roles for pituitary adenylate cyclase-activating peptide (PACAP) expression and signaling in the bed nucleus of the stria terminalis (BNST) in mediating the behavioral consequences of chronic stress, Journal of Molecular Neuroscience, 42(3), 327-40.
  • Hammack, S.E., Guo, J., Hazra, R., Dabrowska, J., Myers, K.M., Rainnie, D.G. (2009) The response of neurons in the bed nucleus of the stria terminalis to serotonin: Implications for anxiety, Progress in Neuro-Psychopharmacology & Biological Psychiatry, 33(8): 1309-20.
  • Hammack, S.E., Cheung, J., Rhodes, K.M., Schutz, K.C., Falls, W.A., Braas, K.M., May, V. (2009) Chronic stress increases pituitary adenylate cyclase-activating peptide (PACAP) and brain-derived neurotrophic factor (BDNF) mRNA expression in the bed nucleus of the stria terminalis (BNST): roles for PACAP in anxiety-like behavior, Psychoneuroendocrinology, 34(6), 833-43.
  • Fox, J.H., Hammack, S.E., Falls, W.A. (2008) Exercise is associated with reduction in the anxiogenic effect of mCPP on acoustic startle, Behavioral Neuroscience 122(4), 943-8.
  • Hammack, S.E., Mania, I., Rainnie, D.G. (2007) Differential expression of intrinsic membrane currents in defined cell types of the anterolateral bed nucleus of the stria terminalis, Journal of Neurophysiology 98(2), 638-56.

The Hammack Laboratory benefits from collaborations with several UVM faculty and Neuroscience Graduate Program graduate students including:

Galen Missig Galen Missig, B.A.
Neuroscience Graduate Program
University of Vermont
Victor May Victor May, Ph.D.
Department of Neurological Sciences
University of Vermont
Tom Longden Tom Longden, Ph.D.
Postdoctoral Associate
University of Vermont
Mark Nelson Mark Nelson, Ph.D.
Chair and University Distinguished Professor
Department of Pharmacology
University of Vermont