Parkinson Disease, Tremor
Conditions
Keywords
Parkinson disease, Vibrotactile stimulation, Tremor
Brief summary
Tremor in Parkinson's disease is a common and highly burdensome symptom. Recent evidence shows that areas in the brain that are underlying Parkinson's tremor overlap with those that respond to somatosensory stimulation. Applying such stimulation to the tremulous limb might therefore influence tremor-related brain activity and thereby potentially reduce tremor. In this study, the investigators explore this possibility and investigate whether tremor specific vibrotactile stimulation at the wrist of the most affected arm influences tremor severity.
Detailed description
Parkinson's disease (PD) is the second most common neurodegenerative disease, of which tremor is a common and highly burdensome symptom. The pathophysiology of tremor involves a cerebral network that consists of basal ganglia and a cerebello-thalamo-cortical motor circuit. Emerging evidence suggests that somatosensory input from the tremulous limb to the brain may influence this network. Specifically, tremor-related activity was observed in primary and secondary somatosensory cortex, and thalamic cells involved in tremor appear to be responsive to somatosensory stimulation as well. Somatosensory afferents may thus play a role in tremor pathophysiology and could therefore be used as treatment target. Here, the investigators will test this hypothesis by investigating the effect of modulating somatosensory input (with vibrotactile stimulation) on tremor severity. The primary objectives are 1) to test whether rhythmic somatosensory input (vibrotactile stimulation) at tremor frequency reduces tremor power of Parkinson's tremor as compared to vibrotactile stimulation at 1.5 times tremor frequency and 2) whether continuous 80Hz vibrotactile stimulation reduces tremor power as compared to sham stimulation. As secondary objectives, the investigators will test whether the effect of vibrotactile stimulation on tremor power depends on the context in which tremor occurs (rest, cognitive coactivation, posture), whether stimulation at tremor frequency reduces tremor power as compared to sham stimulation, and whether vibrotactile stimulation has an effect on two other common PD symptoms: impaired gait and bradykinesia. The investigators will include 27 patients with Parkinson's disease and rest as well as postural tremor. The intervention involves subtle mechanical vibrations on the wrist or ankles. This is a non-invasive and painless way to provide somatosensory stimuli, in a continuous (80Hz) or rhythmic fashion (brief bursts of 80 Hz at tremor or step frequency). The investigators expect that this study will provide mechanistic insights into if and how somatosensory (vibro-tactile) afferents influence the cerebral tremor circuit in Parkinson's disease, and may provide a solid basis for designing further clinical treatment studies.
Interventions
DEVICEVibrotactile stimulation at tremor frequency
Mechanical vibrations are applied at brief bursts of 80Hz that occur at the individual tremor frequency. Vibrations are delivered via a small device, which is worn on the wrist of the most-affected arm.
DEVICEVibrotactile stimulation at tremor frequency*1.5
Mechanical vibrations are applied at 80Hz bursts at individual tremor frequency\*1.5. Vibrations are delivered via a small device, which is worn on the wrist of the most-affected arm.
DEVICEVibrotactile stimulation at continuous stimulation
Continuous 80Hz stimulation is applied via a small device worn on the wrist of the most-affected arm.
DEVICEVibrotactile stimulation 10% below and above step frequency
This intervention is applied during assessment of gait. Two devices are worn on both ankles which allows alternating stimulation of both ankles with brief bursts of 80 HZ at the individual step frequency plus or minus 10%.
Sponsors
Parkinson's Foundation
Donders Centre for Cognitive Neuroimaging
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
* 18-80 years old and able to provide informed consent * Have a diagnosis of idiopathic PD made by a movement disorders specialist * Medically optimized without planned medication changes for the duration of the study • Resting tremor subscore \>/= 2 of the most-affected arm on the Movement Disorders Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) item 2.10 * Postural tremor subscore \>/= 1 of the most-affected arm on the MDS-UPDRS item 3.15 * Signed informed consent
Exclusion criteria
* The presence of additional neurologic diseases that might confound testing or the coexistence of PD and essential tremor together (action tremor that was present prior to the development of parkinsonism) * Moderate to severe peripheral neuropathy (reduced vibratory sensation) at the upper extremities, quantified with a graduated tuning fork * Montreal cognitive assessment (MoCA) score \< 20 or previously documented dementia * Unable to walk without walking aid
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| The effect of vibrotactile stimulation at tremor frequency on tremor severity with active control | 25 minutes | The investigators will investigate the effect of frequency specific stimulation compared to an active control condition, averaged across three different contexts (rest/posture/cognitive coactivation). Specifically, we will test the change in log transformed tremor power from baseline to stimulation, as a function of stimulation setting (bursts at tremor frequency vs. bursts at 1.5 times tremor frequency). |
| The effect of continuous vibrotactile stimulation on tremor severity | 25 minutes | The investigators will investigate the effect of continuous stimulation compared to sham stimulation, averaged across three different contexts (rest/posture/cognitive coactivation). Specifically, we will test the change in log transformed tremor power from baseline to stimulation, as a function of stimulation setting (continuous 80Hz stimulation vs. sham). For the two primary outcomes measures, Bonferroni correction will be applied to correct for multiple comparisons. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| The effect of vibrotactile stimulation at tremor frequency on tremor severity with passive control | 25 minutes | The investigators will explore the change in log transformed tremor power from baseline to stimulation, as a function of stimulation setting (bursts at tremor frequency vs. sham). |
| The effect of continuous vibrotactile stimulation on bradykinesia | 10 minutes | The average button presses per second in the keyboard finger tapping test during continuous 80Hz stimulation versus sham will be investigated. |
| The effect of vibrotactile stimulation on gait | 10 minutes | Time to complete the timed up and go task will be investigated, comparing stimulation 10% above step frequency/10% below step frequency/sham |
| Investigating the effect of continuous stimulation on tremor severity in 3 different contexts | 25 minutes | The investigators will explore the change in log transformed tremor power from baseline to stimulation, as a function of stimulation setting (continuous 80Hz stimulation vs. sham) and context (rest/posture/cognitive coactivation). |
| Investigating the effect of vibrotactile stimulation at tremor frequency on tremor severity in 3 different contexts | 25 minutes | The investigators will explore the change in log transformed tremor power from baseline to stimulation as a function of stimulation setting (bursts at tremor frequency/bursts at 1.5 times tremor frequency) and context (rest/posture/cognitive coactivation). |
| The effect of vibrotactile stimulation on freezing | 10 minutes | Number of freezing episodes during the timed up and go task will be investigated, comparing stimulation 10% above step frequency/10% below step frequency/sham |
Countries
Netherlands
Outcome results
None listed