I am using EEGLab to process my electroencephalografic data (i.e. brain’s electric activity), but I wanted to have an interactive visualisation showing how different filter settings change my data. I prefer using R to Matlab, so I decided to create a Shiny app that would do just that.
I tried to filter brainstem’s activity during several speech conditions using Butterworth band-pass filter to get rid of the artefacts.
I wrote a butterHz function which is based on butter_filtfilt.m from the EEGLab Matlab package and is using butter function from the signal R package.
Here I used a time-domain waveform of speech-evoked Auditory Brainstem Responses to demostrate the use of the Butterworth filter.
The code is available on GitHub.