Date of Award
5-2025
Document Type
Thesis
Degree Name
Master of Arts in Psychological Science
Department
Psychology
First Reader/Committee Chair
Jacob Jones
Abstract
Parkinson’s disease (PD) is a neurodegenerative disorder resulting in both motor and cognitive deficits. Salthouse (1990) proposed the Information Processing Speed (IPS) Theory that a reduced cognitive processing speed is a significant factor that accounts for the negative relationship between age-related variance and cognition. Parkinson’s is an idiopathic disorder, meaning that the cause is unknown, with most patients being 60 years and older. If the IPS theory suggests that an increased age affects the slowing of IPS, which then impairs cognition, PD, a disorder involving older adults, should also follow this pattern. However, no studies have assessed the IPS theory in groups affected by Parkinson’s disease and whether cognitive degradation follows a similar trend.
In this study, we evaluated whether information processing speed mediates five higher-order cognitive domains: attention, pragmatic language, visual-spatial ability, learning, and memory. We also identified the conditions under which the effect occurs by using primary diagnosis (Parkinson’s Disease vs. Healthy Control) as a moderated variable.
The results supported the Salthouse Processing Speed theory; older Parkinson’s Disease affected individuals showed a slower processing speed significantly impairing visuospatial and animal fluency ability. Additionally, compared to healthy control groups, the Parkinson’s disease-affected groups were more strongly influenced by processing speed in visuospatial, verbal learning, and global cognition ability. These results can aid in processing speed-dependent cognitive functioning and improve treatments for these speed-dependent cognitive areas.
Recommended Citation
Cuellar-Rocha, Priscilla, "PARKINSON’S DISEASE AND PROCESSING SPEED THEORY DOES PROCESSING SPEED MEDIATE HIGHER-ORDER COGNITIVE FUNCTIONING?" (2025). Electronic Theses, Projects, and Dissertations. 2122.
https://scholarworks.lib.csusb.edu/etd/2122
