EOG correction of blinks with saccade coefficients: a test and revision of the aligned-artefact average solution.
OBJECTIVE
The 'aligned-artefact average' (AAA) procedure was advanced by the authors as a technique suitable for removing eye movement-related artefacts from the EEG. It was proposed that this method would correct both blink and non-blink artefact from the EEG, using the same set of correction coefficients (Bs). However, recent evidence suggests that this simplification is not always accurate. Thus, we test here a revision of the AAA, including an appropriate allowance for the radial EOG (REOG) component, that does allow the use of the same Bs for the correction of blink and non-blink artefact.


METHODS
Blink (and saccade) ERP data from 15 subjects were corrected using the AAA method, with Bs calculated from the same blink (and saccade) data set (referent waveforms), or a different set of blink (and saccade) data, or using the new revised AAA procedure (RAAA).


RESULTS
AAA Bs calculated from saccades corrected blinks poorly (and vice versa). However, the RAAA Bs corrected blink ERPs better than blink-derived Bs, and saccade ERPs better than saccade-derived Bs. It was also found that irrespective of correction type, inclusion of REOG improved correction.


CONCLUSIONS
EOG correction is more accurate when the radial channel is included, but inclusion of REOG (and/or HEOG) is not sufficient to resolve the discrepancy between blink and saccade correction. Using the RAAA procedure, both blink and non-blink data can be corrected using the same set of Bs.
Croft
R J
RJ
Department of Behavioural & Cognitive Sciences, Imperial College of Science, Technology & Medicine, Charing Cross Hospital, St. Dunstan's Road, London, UK. r.croft@ic.ac.uk
Barry
R J
RJ
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D016477:Artifacts; D001767:Blinking / Q000502:physiology*; D004569:Electroencephalography; D004585:Electrooculography; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D012438:Saccades / Q000502:physiology*