Mellon, Deforest
Primary Appointment
Professor, Biology
Contact Information
PO Box 400328
Gilmer Hall Room, 281
Telephone: 434-982-5766
Email: dm6d@virginia.edu
Website: http://www.virginia.edu/biology/faculty/mellon.htm
Research Disciplines
Neuroscience
Research Interests
Sensory System Organization and Development
Research Description
The major thrust of my research is the exploration of nerve cell dendritic function. Dendrites are the input processes of neurons and in most central nerve cells they receive the majority of excitatory and inhibitory synaptic contacts from other cells. Recent work has revealed an enormous functional complexity to dendritic action, based upon a diversity of ion channel types that are differentially expressed in different regions of the dendritic tree. This diversity of spatially segregated ion channels within the dendrites embues these structures with an array of mechanisms that modulate the electrical signalling properties of the neuron as a whole, i.e., its input/output relations. We are studying the dendritic properties of parasol cells within the higher central olfactory pathway of the freshwater crayfish. These unresting, local forebrain interneurons are large collector' multimodal sensory nerve cells with extensive and functionally complex dendritic arbors that receive olfactory, photic, and tactile input from various parts of the crayfish body. The parasol cells serve as a model cellular system for the exploration of questions about dendritic function: how is sensory input to the parasol cells modified by different types of electrical activity (eg, impulse bursts) within the dendritic branches ? What are the consequences to the input/output properties of parasol cells of the synchronous periodic depolarizations that impinge upon them from oscillator centers in other parts of the brain? Elucidation of the role of complex dendritic properties will continue to be a crucial step in comprehending how the brains of animals perceive the physical world and generate appropriate behaviors.