To identify the peak frequency during a task for each participant, I perform the following steps:
- epoch the time window of interest and separate them into trials.
- isolate the electrode of interest - C3.
- compute power spectrum for each epoch/trial (7s long) using welch(1s window, zero overlaps)
- isolate 13-30Hz power values
- average 13-30Hz power values across trials
- identify the max power and its corresponding frequency.
My questions are:
- Do I need to detrend the data after step1?
- Do I need to detrend the frequency after step 3 as the power spectrum of EEG will be biased towards the lower frequencies?
- If I need to detrend the frequency, should I use a linear or exponential line?
- The purpose of using peak frequency is to identify subject-specific frequency for desynchronization calculations, do you have any alternate suggestions to my method?
Thank you so much for taking the time to respond to my questions.