Patients with Parkinson's disease or Essential Tremor commonly experience uncontrollable tremor in the hands. These symptoms range from bothersome to debilitating and their occurrence is frequent and unpredictable. Usually the patients are otherwise fully functional but their abilities to use their fingers in critical tasks, such as writing, typing, utensils or smart phone use, are greatly affected. In fact our fingers have phenomenal dexterity coupled with significant strength and their role and significance in our daily life simply cannot be overstated. Here we propose to monitor (in-time) the electrical signal associated with the involuntary tremor and counteract it through active stimulation of the corresponding antagonist muscles, thus keeping the hand and fingers still and mitigating the Parkinson’s symptoms.
The system is comprised of three main components – sensor, controller and stimulation transducers. The sensor serves as an antenna for the electrical signals by a 2D matrix fastened around the patient’s forearm (the hand and finger muscles are in the forearm).
Detection of the electrical signals from muscles undergoing contraction has been done for a long time. The signals can be continuously analyzed with help of an attached miniature computer (the controller). Once the tremor signals are mapped at the respective muscles one can generate counteracting voltages via stimulation transducers to the antagonistic muscles, mitigating the hand movement. The stimulation transducers could be attached in the form of a band strapped around the forearm. It is also conceivable that the sensor matrix can be used bi-directionally and serve as stimulation transducer as well. Overall the system works similarly to the active noise canceling – applying matching stimulation in phase to negate the undesired tremors.
We are not aware of a product that uses muscle stimulation to mitigate involuntary tremors. This idea does not use new technology, it combines recently available technologies. There is no known cure for Parkinson’s disease and patients (nearly 1 million in the USA alone) with tremors would benefit tremendously as well as people needing fine hand and finger control.
The following anonymous quote, illustrates the hand tremor predicament: “I know my spouse is angry with me when we have soup for supper.”
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