A machine-readable storage medium containing a program element for execution by a computing device for performing spike and artifact detection in EG data. The program element comprises a spike detection module for processing EG data to detect spikes. Each spike is a candidate having a likelihood of being related to a physiological event of interest. The program element further comprises an artifact detection module. The artifact detection module is operative to compute respective models of events manifested by the respective spikes detected by the spike detection module, to use the computed models to determine which spikes among the spikes detected by the spike detection module have a high likelihood of being artifacts, to filter the spikes detected by the spike detection module on the basis of the computed models to produce filtered data and to output the filtered data.