Director, Center for the Integrative Study of Animal Behavior
Professor, Psychological and Brain Sciences
The role of psychobiology in understanding abnormal behaviors has become increasingly important over the past decade. My research focuses on the neurobiology of stress, a critical variable in the development and expression of many psychological disorders. By using simple animal models that permit the manipulation and control of stress and other relevant variables, I hope to understand the neural causes and consequences of abnormal behavior. I am using such models to characterize alterations in neural plasticity resulting from stress.
Stress has been hypothesized to play a major role in several disorders, and the neurotransmitter systems and brain structures that are altered by stress have been implicated in a variety of psychological disorders. Thus, assessment of the effects of stress on these neurotransmitter systems and structures may have important implications for the causes and prevention of these disorders. Prefrontal cortex is a target for hormones involved in the stress response and has been implicated in disorders such as schizophrenia and depression that are exacerbated or precipitated by stress. Thus, understanding the effects of stress on prefrontal cortex is critical for understanding the influence of stress on psychopathology.
My lab is examining the effects of chronic stress and stress hormones on behaviors mediated by prefrontal cortex, as well as the changes in neural pharmacology, physiology, and morphology that underlie these effects. We have demonstrated that both chronic stress and exposure to the stress hormone corticosterone reorganize dendrites of neurons in prefrontal cortex. We are now more fully characterizing these effects, assessing their functional significance, and elucidating mechanisms underlying them.
In collaboration with colleagues at the National Institute on Alcohol Abuse and Alcoholism, the National Institute for Mental Health, and the University of Southern California School of Pharmacology, we are also using transgenic mice to investigate the roles of alterations in the serotonergic and glutamatergic systems in increased risk for neuropsychiatric disorders as well as contributions of these neurotransmitter systems in stress-induced dendritic changes. These studies will provide data relevant for understanding the neurobiological mechanisms underlying both altered corticolimbic function and risk for mood disorders in the presence of environmental stressors.
Wilber, A.A., Walker, A.G., Southwood, C.J., Farrell, M.R., Lin, G.L., Rebec, G.V., & Wellman, C.L. (2011). Chronic stress alters neural activity in medial prefrontal cortex during retrieval of extinction. Neuroscience, 174, 115-131.
Christian, K.M., Miracle, A.D., Wellman, C.L., & Nakazawa, K. (2011). Chronic stress-induced hippocampal dendritic retraction requires CA3 NMDA receptors. Neuroscience, 174, 26-36.
Martin, K.P., & Wellman, C.L. (2011). NMDA receptor blockade alters stress-induced dendritic remodeling in medial prefrontal cortex. Cerebral Cortex, 21, 2366-2373.
Bortolato, M., Chen, K., Godar, S.C., Chen, G., Wu, W., Rebrin, I., Scott, A.L., Farrell, M.R., Wellman, C.L., & Shih, J.C. (2011). Social deficits and perseverative behaviors, but not overt aggression, in MAO-A hypomorphic mice. Neuropsychopharmacology, 2674ñ2688.
Farrell, M.R., Sayed, J.S., Underwood, A.R., & Wellman, C.L. (2010). Lesion of infralimbic cortex occludes stress effects on retrieval of extinction but not fear conditioning. Neurobiology of Learning and Memory, 94, 240-246.
Wilber, A.A., Lin, G.L., & Wellman, C.L. (2010). Glucocorticoid receptor blockade in the interpositus nucleus reverses maternal separation-induced deficits in adult eyeblink conditioning. Neurobiology of Learning and Memory, 94, 263-268.
Garrett, J.E., & Wellman, C.L. (2009). Chronic stress effects on dendritic morphology in medial prefrontal cortex: sex differences and estrogen dependence. Neuroscience, 162, 195-207.
Holmes, A., & Wellman, C.L. (2009). Stress-induced prefrontal reorganization and executive dysfunction in rodents. Neuroscience and Biobehavioral Reviews, 33, 773-783.
Wilber, A.A., & Wellman, C.L. (2009) Neonatal maternal separation-induced changes in glucocorticoid receptor expression in posterior interpositus interneurons but not projection neurons predict deficits in adult eyeblink conditioning. Neuroscience Letters, 460, 214-218.
Wilber, A.A., Southwood, C.J., & Wellman, C.L. (2009). Brief neonatal maternal separation alters extinction of conditioned fear and corticolimbic glucocorticoid and NMDA receptor expression in adult rats. Developmental Neurobiology, 69, 73-87.
Wellman, C.L., Izquierdo, A., Garrett, J.E., Martin, K.P., Carroll, J., Millstein, R., Murphy, D.L., Lesch, K.-P., & Holmes, A. (2007). Genetic inactivation of the serotonin transporter causes impairment of stress-coping and extinction-recall and medial prefrontal cortex abnormalities. Journal of Neuroscience, 27, 684-691.
Wilber, A.A., Southwood, C.J., Steinmetz, J.E., & Wellman, C.L. (2007). Neonatal maternal separation alters adult eyeblink conditioning and glucocorticoid receptor expression in the interpositus nucleus of the cerebellum. Developmental Neurobiology, 67, 1751-1764.
Miracle, A.D., Brace, M.F., Huyck, K.D., Singler, S.A., & Wellman, C.L. (2006). Chronic stress impairs recall of extinction of conditioned fear. Neurobiology of Learning and Memory, 85, 213-218.
Izquierdo, A., Wellman, C.L., & Holmes, A. (2006). Rapid dendritic retraction in medial prefrontal neurons and impaired fear extinction following exposure to uncontrollable stress. Journal of Neuroscience, 26, 5733-5738.
Brown, S.M., Henning, S., & Wellman, C.L. (2005). Short-term, mild stress alters dendritic morphology in rat medial prefrontal cortex. Cerebral Cortex, 15, 1714-1722.
Cook, S.C., & Wellman, C.L. (2004). Chronic stress alters dendritic morphology in rat medial prefrontal cortex. Journal of Neurobiology, 60, 236-248.
Wellman, C.L. (2001). Dendritic reorganization in pyramidal neurons in medial prefrontal cortex after chronic corticosterone administration. Journal of Neurobiology, 49, 245-253.
The College of Arts