SPECT and fMRI Analysis of Motor and Cognitive Indices of Early Parkinson's Disease: The Relationship of Striatal Dopamine and Cortical Function.

摘要

Parkinsonism is the result of decreased striatal dopamine integrity. Neurotoxins often selectively affect dopamine producing cells and lead to behavioral manifestations of parkinsonism. The effects of parkinsonism is impaired motoric and strategic/working memory cognitive performance. Both motoric and strategic/working memory deficits also increase in community dwelling healthy elderly individuals as age increases, suggesting a link between age-associated parkinsonism and age-associated motoric and cognitive changes. In the present study we sought to investigate the integrity of the striatal dopaminergic system and cortical neural systems involved in motoric and strategic/working memory operations in healthy aging (HA) participants, patients with PD, and healthy young participants (YNC). Due to delays in obtaining approval from the Human Subjects Research Review Board of Regulatory Compliance and Quality at the USAMRMC (delayed until 2002), we were unable to obtain the radioligand for SPECT imaging. Access to a new radioligand was attempted through Boston Life Sciences, but production of that ligand was suspended. Parallel to our attempts to obtain HSRRB approval and the appropriate radioligand, we developed a novel imaging technique that probes the integrity of white matter connectivity in the human brain. We were able to combine this imaging modality with fMRI studies of aging and behavior to assess the relationship between white matter integrity and cognitive processes involved in working memory in aging and in patients with Parkinson's disease.