Dr. Allen received his doctoral degree in Pharmacology from the University of Texas Health Science Center
in Dallas. He was a Research Assistant Professor at the University of Maryland, Baltimore, and a Research
Affiliate at the New York State Department of Health, Wadsworth Center for Laboratories and Research in Albany,
New York. He has special expertise in neurophysiology.
Research Interests—Overview
A selective evolutionary advantage seems to be conferred on individuals whose physiological rhythms are synchronized
to environmental conditions. Thus, the majority of organisms studied show twenty-four hour rhythms in physiological
processes termed circadian rhythms. Disturbances in circadian rhythms are known to contribute to a variety
of diseases and to impair mental and physical performance. The circadian system consists of three conceptual
components, a timekeeping oscillator, input pathways providing environmental information, and output pathways
sending timing information to peripheral clocks and organs. The timekeeping oscillator or clock resides, in
mammals, in the suprachiasmatic nucleus (SCN) a bilateral structure located in the hypothalamus. This circadian
clock is synchronized (entrained) to the environmental light-dark cycle via a direct axonal projection (retinohypothalamic
tract, RHT) from a specialized subset of retinal ganglion cells. SCN neurons ouput timing information via
projections to other hypothalamic nuclei and by releasing neurohumoral factors.
The long-term goal of our research is to understand the functional properties of SCN neurons and how the
circadian clock regulates these properties. To reach this goal we are pursuing four lines of research: