Gait Disorders, Neurologic, Parkinson Disease, Visuospatial/Perceptual Abilities
Conditions
Keywords
Freezing of gait, Subthalamic nucleus, Visuospatial attention, Deep brain stimulation
Brief summary
The purpose of this research is to determine how deep brain stimulation (DBS) for Parkinson's disease affects attention and visuospatial function. Additionally, this study will evaluate how deficits in visual attention are associated with freezing of gait (FOG) in Parkinson's disease. There is currently no reliable treatment for FOG and little is understood about the underlying reason this occurs. Some recent research has found that stimulating the right side of the brain seems to improve FOG. The right side of the brain is also paramount for visual attention, which is why investigators are conducting this study.
Detailed description
FOG is a common and frequently disabling symptom of PD, affecting more than half of all PwPD. It remains a complex and incompletely understood phenomenon, with no currently approved therapies. FOG is often exacerbated during dual-tasks where attention is divided to multiple tasks. A well known method of provoking FOG by PwPD and neurologists alike is to walk through doorways or through a crowded space, regions where spatial attention is necessary. Similarly, significant visuospatial attention deficits have been found in PwPD who freeze compared to those do not. Further evidence demonstrates that the STN is part of the circuit which modulates spatial attention, and that STN-DBS has a significant impact on visuospatial attention and is notably improved with right sided stimulation. Indeed, visuospatial attention is largely considered to be predominantly lateralized to the right hemisphere. Interestingly, one study showed that right STN-DBS stimulation affecting a volume of activated tissue (VAT) connected to the right sensorimotor cortex showed a significant association with reduction in FOG. The impact of STN-DBS on visuospatial attention and the degree to which this change in attention is associated with changes in FOG has not yet been studied, and may well explain part of the pathophysiology of FOG and how to treat PwPD who freeze. The present study will build on the aforementioned research by prospectively evaluating the impact of lateralized STN-DBS stimulation on visuospatial attention in PwPD, and correlating this with change in FOG.
Interventions
DEVICELeft STN-DBS on, right STN-DBS off first
There will not be any change to baseline DBS stimulation settings, only each side will be sequentially turned off during cognitive and freezing of gait assessments.
DEVICERight STN-DBS on, left STN-DBS off first
There will not be any change to baseline DBS stimulation settings, only each side will be sequentially turned off during cognitive and freezing of gait assessments.
Sponsors
Medical University of South Carolina
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)
Masking description
Investigator will not be blinded as they will need to make adjustments to patient deep brain stimulation settings during testing.
Intervention model description
Patients will be randomized to 2 groups which will determine the side of stimulation that is kept on first while cognitive tests and assessments for freezing of gait are performed. Patients will then complete the same testing on the contralateral side.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Subjects above 18 years of age * Subjects with freezing of gait * Subjects with bilateral STN-DBS surgery as part of their clinical care for Parkinson's disease
Exclusion criteria
* Uncorrected visual or hearing impairments, as indicated by self-report * Individuals who are pregnant or expect to become pregnant during the course of the study * Individuals with dementia or relevant brain lesions impacting cognition or gait
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Characterize the individual impact of lateralized STN DBS stimulation on freezing of gait in Parkinson's disease | 1 hour | Investigators hypothesize that right STN stimulation will have a significant association with reduction in freezing of gait, as measured by timed up and go task, compared to left STN stimulation and no stimulation. |
| Determine if there is a correlation between the change in visuospatial function due to lateralized STN DBS stimulation and change in freezing of gait (FOG) in Parkinson's disease | 1 hour | Investigators hypothesize that right STN stimulation induced improvement in attention will be associated with improvement in FOG. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Determine if there is a correlation between the change in Flanker task due to lateralized STN DBS stimulation in Parkinson's disease | 30 minutes | Investigators hypothesize that right STN stimulation will have a significant association with change in attention, as measured by the flanker task, compared to left STN stimulation and no stimulation. |
| Determine if there is a correlation between the change in Go-No-Go task due to lateralized STN DBS stimulation in Parkinson's disease | 30 minutes | Investigators hypothesize that right STN stimulation will have a significant association with change in attention, as measured by the Go-No-Go task, compared to left STN stimulation and no stimulation |
Countries
United States
Contacts
CONTACTNathan DeTurk, MD
PRINCIPAL_INVESTIGATORNathan DeTurk, MD
Medical University of South Carolina
Outcome results
None listed