Publication date: Mar 21, 2020
Pupillary response reflects cognitive workload during processing speed, working memory, and arithmetic tasks in Parkinson’s disease (PD). Abstract reasoning, a higher-order cognitive function that relates different objects, events, or thoughts in a similar manner, may also be compromised in PD. The aim of this study was to compare pupillary response as a measure of cognitive workload while completing a verbal abstract reasoning test between patients with PD and age-matched controls.
Nineteen non-demented individuals with PD (66.6?+/-?8.9 years) and 10 healthy controls (65.3?+/-?7.3 years) were recruited. A remote eye tracker recorded the pupillary response at 60?Hz, while the participants were performing the Similarities test of Wechsler Adult Intelligence Scale-IV. Outcome measures included pupillary response, evaluated by the Index of Cognitive Activity (ICA), and behavioral responses of the Similarities test.
The PD group (scaled scores = 8.9?+/-?2.2) did not show impairment in behavioral performance on Similarities test compared with healthy controls (scaled scores = 8.8?+/-?2.3; p = .91). However, the PD group (ICA = .32 +/- .09) demonstrated significantly greater cognitive workload during the Similarities test compared to controls (ICA = .24 +/- .08; p = .03).
Non-demented individuals with PD exerted greater cognitive workload to complete a verbal abstract reasoning task despite similar behavioral performance compared to healthy controls. Clinical utilities of pupillary response to detect and monitor early impairment in higher-order executive function will be the subject of further study in the PD population.
Moon, S., Kahya, M., Lyons, K.E., Pahwa, R., Akinwuntan, A.E., and Devos, H. Cognitive Workload during Verbal Abstract Reasoning in Parkinson’s Disease: A Pilot Study. 24445. 2020 Int J Neurosci.
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