Date on Master's Thesis/Doctoral Dissertation


Document Type

Doctoral Dissertation

Degree Name

Ph. D.


Anatomical Sciences and Neurobiology

Degree Program

Anatomical Sciences and Neurobiology, PhD

Committee Chair

Lundy, Robert

Committee Co-Chair (if applicable)

Hubscher, Charles

Committee Member

Bickford, Martha

Committee Member

Krimm, Robin

Committee Member

Mitchell, Thomas


Taste--Physiological aspects; Neuropeptides


Many current health problems including obesity, hypertension, stroke, heart disease, and type 2-diabetes can be attributed to diet. One powerful determinant of food selection is how good or bad a food 'tastes' (e.g. affective value), and is ranked highly by consumers as their top reason for choosing a food (e.g. preference). Learning plays an important role in the establishment and strengthening of food preference and, thus in guiding food choice and calories consumed. The basis of such learning is provided, in part, by limbic system modulation of gustatory neural processing at lower levels in the medulla and pons. I hypothesize that specific limbic system neuropeptide pathways underlie this neural modulation and, thus, function in assigning affective value to taste information and establishing preference behavior. I have identified two neuropeptides, corticotrophin releasing hormone (CRH) and somatostatin (Sst), which are expressed in limbic system neurons projecting to the pontine taste area. Studying the cellular components and nature of these different cell type projections and locations helps us understand the role that forebrain plays in controlling ingestive behaviors in the hindbrain. In doing so, I was able to prove that the inhibitory neurotransmitter of GABA is expressed by Sst-producing neurons potentially to exert a neuromodulatory function.