I am reading a paper in which they filter EEG signal using a notch filter to remove the power supply component of 50 Hz, then a high pass filter at 0.3 Hz to remove artifacts resulting from breathing, and finally a low pass filter with a cut-off frequency of 40 Hz.
Is there any difference to simply using a band pass filter of 0.3 – 40 Hz?
Additionally, why the notch at 50 Hz when everything 40+ Hz is thrown away, anyway?