The basal ganglia are a group of subcortical nuclei associated with several functions including both motor and non-motor (control of voluntary movement, routine behaviours and emotions among others) (Tropea & Chen-Plotkin, 2018).  Tropea and Chen-Plotkin (2018) further explain that progressive dysfunction of the basal ganglia is a well-documented hallmark of Parkinson’s disease (PD). While deterioration of basal ganglia structures is associated with worsening motor symptoms and cognitive decline, the laterality of the side of symptom onset and its relationship to disease progression remains unexplored (Marin, Bonastre, Mengod, Cortés, & Rodríguez-Oroz, 2015). Hence, I will use longitudinal MRI volumetric data to investigate patterns of basal ganglia deterioration over time to assess how this relates to motor laterality and cognitive decline.