We investigate the brain networks and neurotransmitters involved in symptoms of movement disord...ers, such as Parkinson's disease, and the mechanisms by which modulating these networks through electrical stimulation affects these symptoms. We are particularly interested in the mechanisms through which neuromodulation therapies like deep brain stimulation affect non-motor brain functions, such as cognitive function and mood. We use imaging of specific neurotransmitters, such as acetylcholine and dopamine, to understand the changes in brain chemistry associated with the clinical effects of deep brain stimulation and to predict which patients are likely to have changes in non-motor symptoms following DBS. Through collaborations with our neurosurgery colleagues, we explore brain function by making recordings during DBS surgery during motor and non-motor tasks. Dr. Mills collaborates with researchers in the Department of Neurosurgery, the Division of Geriatric and Neuropsychiatry in the Department of Psychiatry and Behavioral Sciences and in the Division of Nuclear Medicine within the Department of Radiology to translate neuroimaging and neurophysiology findings into clinical applications. view more

Molecular imaging of effects of deep brain stimulation on cognitive function in Parkinson's dis...ease view more

Effects of transcranial direct current stimulation on mood disorders and cognitive dysfunction ...in Parkinson's disease view more

Relationship between patient-reported and objective cognitive impairments in Parkinson's diseas...e view more

The studies of the Functional Neurosurgery Lab currently test whether neural activity related t...o the experimental vigilance and conditioned expectation toward pain can be described by interrelated networks in the brain. These two psychological dimensions play an important role in chronic pain syndromes, but their neuroscience is poorly understood. Our studies of spike trains and LFPs utilize an anatomically focused platform with high temporal resolution, which complements fMRI studies surveying the whole brain at lower resolution. This platform to analyze the oscillatory power of structures in the brain, and functional connections (interactions and synchrony and causal interactions) between these structures based upon signals recorded directly from the waking human brain during surgery for epilepsy and movement disorders, e.g. tremor. Our studies have demonstrated that behaviors related to vigilance and expectation are related to electrical signals from the cortex and subcortical structures.

These projects are based upon the combined expertise of Dr. Nathan Crone in recordings and clinical management of the patients studied; Dr. Anna Korzeniewska in the analyses of signals recorded from the brain; Drs. Claudia Campbell, Luana Colloca and Rick Gracely in the clinical psychology and cognitive neurology of the expectation of pain and chronic pain; Dr. Joel Greenspan in quantitative sensory testing; and Dr. Martin Lindquist in the statistical techniques. Dr. Lenz has conducted studies of this type for more than thirty years with continuous NIH funding. view more