Overview
Strokes are one of the leading causes of long term disability and death in the United States. A stroke occurs when the blood supply to the brain is blocked, damaging parts of the brain. Many stroke survivors have difficulty completing dexterous hand movements and manipulating objects due brain damage in the sensorimotor cortex. Damage to these areas can cause decreased motor movements and tactile sensation on the affected side. Research shows that tactile sensation is necessary for maintaining grip, grading grip forces and decreasing object slippage. Therefore, it is important to address tactile sensation with motor performance during stroke rehabilitation to improve performance outcomes among stroke survivors.
Description
A novel intervention that has shown immediate improvements in tactile sensation is called stochastic resonance stimulation. SRS is a phenomenon where cutaneous sensation can be enhanced with the presence of tactile noise in a nonlinear system. This theory suggests that the application of an imperceptible vibrotactile stimulation increases the synchronization of afferent neurons firing to the somatosensory cortex, ultimately increasing the excitability of mechanoreceptors in the skin suggesting that afferent signals from the periphery to the somatosensory cortex influence motor movements. However, more research is needed to document the changes in motor performance with the use of SRS and it is unclear how SRS stimulation changes different measurable sensory processing differences
Eligibility
Inclusion Criteria:
- Stroke survivors over the age of 18
- At least six months post stroke
- Ability to provide verbal informed consent and written informed consent
- Score of at least 56 on the Fugl meyer assessment total motor scores
- Able to detect at least 6.65 (300 grams) on the Semmes Weinstein monofilament on both the pads of the thumb and index finger
- Able to complete the nine hole peg test
- Able to reliably express pain, discomfort, or fear
- Speak english
Exclusion Criteria:
- History of upper extremity orthopedic conditions, such as arthritis, surgery, etc.
- Aphasia caused by stroke
- Does not have AROM
- Currently have muscle contractures in upper extremity
- Participating in other research studies
- Patients with electrically operated implanted device (e.g. cardiac pacemaker/defibrillator, drug delivery pump, and neurostimulator)
- History of SMI (e.g. schizophrenia, schizoaffective disorder)
- History of neurodegenerative disability (e.g. Multiple Sclerosis, Parkinson's Disease)
- Have received botulinum injections in the paretic limb within the past three months