Robert S. Bridges | PhD, MS, BA

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• Professor Emeritus
• Section of Neuroscience and Reproductive Biology

Education

• PhD, University of Connecticut, 1974
• MS, University of Connecticut, 1972
• BA, Earlham College, 1969
• Postdoctoral Fellowship, Rutgers University, 1975-1977
• Postdoctoral Fellowship, UCLA, 1977-1978

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Research Activities

My laboratory’s research efforts focus upon the effects of the hormones of pregnancy and lactation upon maternal behavior and the neuroendocrine events that characterize these physiological states. Specifically, the actions of the hormone prolactin and the neural prolactin system are a main subject of study. We also have a keen interest in the longer term effects of reproductive experience in female mammals upon neural processing as a model for adult neuroplasticity. Possible alterations in dopaminergic and central lactogenic receptor systems as a function of reproductive experience are studied in the context of neuroendocrine and behavioral plasticity. Another area of research explores the neurobiological events underlying the establishment and activation of maternal memory, including the roles of pregnancy, birth, and the lactational state in this process.

Neurobiological Regulation of Maternal Behavior

The regulation of the onset of maternal behavior at parturition is regulated in part by the hormonal changes that accompany pregnancy and birth. Specific roles for the lactogenic hormones, prolactin and placental lactogens, together with their neural sites and modes of action have served to elucidate crucial factors that contribute to the normal and possibly abnormal expression of maternal care during the postpartum period. Moreover, research efforts to understand how the changes in the endocrine system and secretion of hormones contribute to much longer changes in neural processing have identified multiple alterations in neural receptor and transmitter activities that result from prior parenting. Delineating the physiology underlying normative maternal care provides a basis for understanding deviations and variations in maternal care, including maternal neglect and abuse.

Selected Research Projects

• “Endocrine Regulation of Maternal Behavior” This NIH funded project examines the biological regulation of maternal behavior in mammals, using the rat as a model. Central sites of endocrine regulation of the onset of maternal care and neurochemical events responsible for the maintenance and retention of maternal behavior are studied.
• “Neuroendocrine Consequences of Reproductive Experience” – This NIH funded project examines the long-term effects of prior pregnancies and lactations on neurochemical functions associated with behavioral and hormonal states. A primary focus is on alterations in neural dopaminergic function resulting from reproductive experience. Studies are conducted using a rat model.

Research and Clinical Interests

• Surgical approaches include stereotaxic surgery and routine endocrine surgeries.
• Lab techniques include radioimmunosassays for hormones, in situ hybridization histochemistry, and immunocytochemistry for neural peptides and receptors. Research Technique
• Behavioral assays include measurement of parental behavior, elevated-plus maze, activity chambers (computerized), assessment of pain, and testing for reproductive behaviors.

 

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Additional Information

Section Collaborators

• Dr. Phyllis Mann, Ph.D., Associate Professor
• Dr. Benjamin Nephew, Assistant Professor

Outside Collaborators

• Dr. David Grattan, Ph.D. – Professor, University of Otago Medical School, Dunedin, New Zealand
• Dr. Jean King, Ph.D. – Professor, University of Massachusetts Medical School, Worcester, MA