Grant: CIHR Fellowship

Essential tremor (ET) is the most common tremor disorder, with a prevalence in older adults comparable to that of osteoarthritis, diabetes mellitus and Alzheimer's disease. It is characterized by tremor that primarily affects the upper extremities. Approximately 75% of people living with ET present with some form of activity limitation, with the severity of these limitations progressing with age. While the cause of ET is not well understood, there is a general consensus that it involves abnormal rhythmic activity in the brain. Therapies for essential tremor focus on tremor reducing medications. Unfortunately, effective pharmacological treatments remain limited. Consequently, it has recently been emphasized that new insights into disease mechanisms are needed to guide the development of more effective therapies. To date, it remains unclear how abnormal rhythmic activity from higher brain centers influences the normal recruitment of muscles and how peripheral reflexes (such as the knee jerk reflex) contribute to ongoing tremor activity. Also, the impact of tremor on the sensory organs found within skeletal muscles and on the contribution of these organs to our ability to sense where our body is in space is not yet known. The goals of these experiments are to improve our understanding of how ET leads to rhythmic muscular activity and to determine the effect of this tremor on the function of the sensory organs located within the muscles themselves. Also, this research will determine the impact of abnormal sensorimotor rhythmic activity on the sensitivity of muscle sensory organs. The results from these studies are expected 1) to increase our knowledge of the neural mechanisms involved in the generation of essential tremor and 2) to gain a better understanding of the motor-sensory deficits associated with tremor disorders. This knowledge will contribute to the development of of more effective anti-tremor therapies.