Anatomical Subtrates of Parkinsonian Tremor

Iwona Stepniewska, Ph.D.
Vanderbilt University, Nashville, TN

Abstract

Tremor is a major component of the parkinsonian triad of symptoms, yet may be the least studied since it isn’t commonly as debilitating as are rigidity and bradykinesia. Dr. Iwona Stepniewska and her Vanderbilt University colleagues will use macaques in a physiologic study aimed at determining if and how various pathways (somatosensory and motor, for example_ overlap within the thalamus. This part of the brain, known to be a “tremor site,” is that which is lesioned in thalamotomy or stimulated with DBS for tremor control. But a
better understanding of its neuroanatomy could lead to applicable human treatments.

Progress Report (as of 8/2002)

Dr. Iwona Stepniewska and her colleagues at Vanderbilt University used their funding to demonstrate that the populations of tremor-related cells overlap within the cerebellar-to-thalamus pathway, thus possibly providing a reason for the increased activity of these cells in parkinsonian brains. She presented these data at the Society for Neurosciences annual meeting and has submitted the work as an expanded project for NIH funding. If her work in macaques can be substantiated in humans, it should be possible to better control this symptom that can be so threatening to careers.