Dipole models of eye movements and blinks

doi:10.1016/0013-4694(91)90154-V

Electroencephalography and Clinical Neurophysiology

Volume 79, Issue 1, July 1991, Pages 36-44

https://doi.org/10.1016/0013-4694(91)90154-V Get rights and content

Abstract

Average EOGs were recorded from 4 subjects for vertical and horizontal eye movements of 15° away from and back to a central fixation point, and for eyeblinks while looking at the fixation point. Using spatio-temporal dipole modelling, several alternative dipole models of the electrical activity of the eyes were compared. A reasonable fit was only obtained if the equivalent dipoles were allowed to take up different locations and orientations depending on the type of eye activity. It appears that (a) the equivalent ocular dipole is located away from the axis of rotation of the eyeball, (b) eyelid movements contribute to a change in location of the dipole in vertical eye movements and blinks, and (c) some of the apparent dipole movement is due to inadequacy of the 3-shell spherical head model near to the eyes. Consequences of the results for eye-artifact correction are discussed.

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^☆: An initial version of this paper was presented as a poster at the Ninth International Conference on Event-Related Potentials of the Brain (EPIC), Noordwijk, The Netherlands, 1989.

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Dipole models of eye movements and blinks☆

Abstract

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Biol. Psychol.

Electroenceph. clin. Neurophysiol.

Vision Res.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Methods for separating temporally overlapping sources of neuroelectric data

Brain Topog.

Influence of eye lid movement upon electro-oculographic recording of vertical eye movements

Aerospace Med.

The residual after correcting event-related potentials for blink artifacts

Psychophysiology