Analysis of 84 Parkinson's patients reveals that declining cognitive function specifically accelerates non-tremor motor symptoms like bradykinesia and rigidity, while leaving characteristic tremors relatively unchanged. The Oxford Quantification in Parkinsonism study tracked participants longitudinally, demonstrating that global cognition and voluntary movement control share overlapping neural pathways that deteriorate together. This finding challenges the traditional view of Parkinson's as primarily a movement disorder by highlighting the interconnected nature of cognitive and motor decline. The research suggests that cognitive assessment could serve as a predictive tool for monitoring disease progression, particularly for symptoms that affect daily functioning most severely. For patients and families, this underscores the importance of cognitive training and neuroprotective strategies early in diagnosis. The distinction between tremor and non-tremor symptoms also has therapeutic implications, as treatments targeting cognitive preservation might simultaneously slow the progression of debilitating motor symptoms like freezing episodes and muscle stiffness. However, the study's modest sample size and observational design limit definitive conclusions about causation versus correlation in this cognitive-motor relationship.