FNIR Study of Cognitive Decline and Reading in Parkinson’s Disease: Preliminary Data

Abstract

As yet, there has been little research applying functional near-infrared spectroscopy (fNIR) neuroimaging studies to aspects of brain activation such as cognitive decline or working memory deficits with reading difficulties in Parkinson’s disease (PD). The purpose of this study is to investigate cerebral hemoglobin concentration changes related to reading and cognitive load tasks in an individual with PD. An individual with PD and a healthy normal person of the same age with no history of neurogenic disorders participated in this study. Functional near-infrared spectroscopy (fNIR) measurements were recorded while the participants carried out a reading task (grandfather passage) and four cognitive load tasks. The fNIR results for the reading task revealed significant differences in the changes in the oxygen concentration levels experienced by the two participants and this was also manifested in both the left and right hemispheres. There were also significant differences between the two participants across all of the cognitive tasks. Unlike the non-PD participant, the PD participant did not exhibit any significant differences among the four cognitive tasks and no significant oxygenation change between the left and right hemispheres when performing cognitive tasks 1 and 4 was observed. These results suggest that PD patients either lack sufficient brain activation to complete linguistic or cognitive tasks or are unable to use oxygenation effectively in a specific brain area when seeking to accomplish these types of tasks.