Aliasing in the visual EEG: a potential pitfall of video display technology

Computerized clinical electroencephalographic (EEG) systems are now widely used, with interpretation performed solely on video monitors. The possibility of artifacts from aliasing of EEG data on a computer screen has received little attention. We describe and illustrate several examples. Photographs of the video display were used. Three cases are shown. Two had escaped initial review and one led to transient changes in patient management. Aliasing artifacts are seen frequently with computerized EEG systems; some may be misinterpreted as EEG activity. Even compliance with current guidelines may not prevent all such artifacts.

[1]  D E Blum,et al.  Computer-based electroencephalography: technical basics, basis for new applications, and potential pitfalls. , 1998, Electroencephalography and clinical neurophysiology.

[2]  J Nilsson,et al.  Principles of digital sampling of a physiologic signal. , 1993, Electroencephalography and clinical neurophysiology.

[3]  G. Comi,et al.  IFCN standards for digital recording of clinical EEG. The International Federation of Clinical Neurophysiology. , 1998, Electroencephalography and clinical neurophysiology. Supplement.

[4]  M Hallett,et al.  A method for determining optimal interelectrode spacing for cerebral topographic mapping. , 1989, Electroencephalography and clinical neurophysiology.