Grant: Master's Award: Canada Graduate Research Scholarships - Master's program

Properly timed behavior, such as deciding when to move or not, as well as where, is essential for survival. The gating or decision making of these movements is governed by the substantia nigra. Evidence points towards the loss of the dopamine neurons in the substantia nigra pars compacta (SNc) in Parkinson’s patients having a role in the observed symptoms, including difficulty in initiating movement and slowness of movement. This proposed project aims to explore how contextual novelty and stimulation history determine the effects of SNc dopamine neuronal activity on voluntary exploratory behavior. We will use DATcre:ChR2 mice and wild-type controls (DATcre only lacking ChR2) to assess whether the context and history of stimulation play a role in voluntary exploratory behavior. Mice will undergo phasic optogenetic stimulation in an open field under conditions that manipulate prior stimulation and environmental novelty. Behavioral measures will include locomotor activity, exploratory rearing, and habituation dynamics. By differentiating whether responses stem from environmental adaptation or plasticity induced by stimulation, this work will clarify how dopamine circuits integrate experience to guide behavior. The outcome of this work will shed light on novel strategies that aim at enhancing motor function in Parkinson’s disease patients and mitigate maladaptive plasticity in addiction and other neuropsychiatric disorders.