Separation of components of hippocampal field potentials by digital filtering on a PC-based microcomputer

A versatile digital filtering system is described which enables separation of wave components of evoked potentials based on their frequencies. The utility of this technique is exemplified by application of digital filtering to hippocampal field potentials. Separation of population spikes from lower frequency synaptic potentials provides less ambiguous interpretation of the compound slope of the field potential during the first 5 milliseconds of the response. The entire procedure of stimulation, data acquisition, and digital filtering was implemented on a PC-compatible computer.