Methods, apparatus, and systems for medical procedures are disclosed herein. For example, a plurality of analog sensor signals and an analog reference signal are received by an analog-to-digital converter to produce respective digitized versions of the analog sensor signals. The respective digitized versions of the analog sensor signals are digital filtered to produce respective filtered digitized versions of the analog sensor signals. The filtered digitized versions of the analog sensor signals are output to a visualization system to provide real time display thereof. The filtered digitized versions of the analog sensor signals are communicated to a digital-to-analog converter to produce an analog version of the filtered digitized versions of the analog sensor signals. The analog version of the filtered digitized versions of the analog sensor signals along with the analog reference signal are output to a recordation system to provide supplemental processing and storage thereof.