Methods for Essential Tremor Assessment: Acoustic Tremor Monitoring (ATM) and Rhythmic Spirals (RS) Methods

There are several techniques of monitoring essential tremors, but there is not yet a standard method developed for the field. A quantitative way to track effects of medication and/or lifestyle treatment would be beneficial for future research in prevention or regression of essential tremors. The two methods evaluated are acoustic tremor monitoring (ATM) and rhythmic spirals (RS). The novel ATM measurement quantifies frequency and amplitude quickly and cost effectively. The tremor patient holds a microphone close to a speaker playing a single frequency tone. The Doppler Effect caused by the shaking microphone distorts the sound recording, and the encoded tremor information can be retrieved by using the Fast-Fourier Transform algorithm. The second method, RS, can be used by patients at home to measure frequency. The RS method is similar to the classic Archimedes spirals, but uses a different form and is timed which allows for the calculation of tremor frequency. The RS and ATM methods produce statistically similar frequency measurements, although ATM has greater precision.