Wavelet analysis of auditory stimuli for ASSR

Abstract

The Auditory Steady State Responses (ASSR) are constant responses to constant stimuli, which can be generated under signals with fast frequencies. They follow a behavior similar to quasi-sinusoidal signals. They capture from the bioelectric activity caused by the stimulus, but they are under unwanted brain activity considered as noise, so the acquisition of these signals requires an algorithm to reduce it. In this work, a signal is analyzed as a stimulus for generation of these kinds of responses and because of its behavior similar to the response that provoked, an algorithm is studied. It includes the Wavelet Transform for reduction of noise after the signal is contaminated. Several comparisons were made and they used different kind of mother Wavelets, in order to choose one that contributes to the greatest noise reduction. The mean squared error in each approach was calculated.