Project Grant R01NS144085

The National Institute of Neurological Disorders and Stroke awarded The University of Iowa $597,466 on September 2, 2026, under the Extramural Research Programs in the Neurosciences and Neurological Disorders program (CFDA 93.853) to investigate dopamine circuitry underlying executive dysfunction in Parkinson's disease.

The research maps how dorsomedial striatal dopamine engages medium-spiny neuron ramping activity during interval timing, an elementary executive process impaired in patients with Parkinson's disease dementia. The project combines dopamine fiber photometry, optogenetics, neuronal recording, and computational modeling in mouse models to explore fundamental striatal circuit mechanisms. Current treatments for Parkinson's motor symptoms do not improve and can worsen executive function, creating a critical need for new neurophysiological markers and targeted interventions.

Work is performed in Iowa City, Iowa. The award runs through May 31, 2031, as a Project Grant (R01NS144085) classified as basic research to reduce the burden of neurological disease. The research addresses a long-term goal of mapping circuits underlying executive functions in Parkinson's disease to inform development of new treatments for cognitive symptoms including working memory, attention, and timing deficits that contribute to dementia, employment loss, nursing home placement, and mortality.