I have taken motor imagery single ch eeg data using aurduino home built amplifier with 12bit and 256 hz sampling fre for 30s.data matrix is .txt file when i open it in matlab using csvread data matrix size is 30×256.How to process further.row-sec,

Data matrix size 30×256 Along row second Along coloum sample point upto 256. Is it converted to voltage format? Fs=256 Single channel data. Aurduino voltage range 0-5v