Females of many species, including humans, tend to have lower thresholds for sensory stimuli and can perform motor tasks more rapidly than males. Moreover, differences in sensorimotor function normally occur during the estrous cycle or menstrual cycle and administration of exogenous gonadal steroid hormones can mimic these natural changes. Dr. Becker has evidence to suggest that estrogen enhances sensorimotor responsiveness by having direct effects on the neurons of the basal ganglia that use dopamine as the neurotransmitter. She will examine this steroid-neurotransmitter relationship by analyzing both presynaptic and postsynaptic effects of estrogen on the dopamine system. By comparing the effects of estrogen on dopamine release and receptor activity in both males and females, Dr. Becker will determine whether the known sex differences in sensorimotor performance is related to biochemical differences. Her experiments not only enhance our understanding of the relationship between hormones and neurotransmitters but also how these processes modulate basal ganglia function. Since the basal ganglia of the brain is involved in a number of clinical disorders, including Parkinson's Disease and Huntington's Disease, these results have important implications for our understanding and treatment of these debilitating disorders and other related movement disorders.
