What is the role of eye movements in sleep state scoring?

Updated: Aug 19, 2019
  • Author: Andres A Gonzalez, MD, MMM, FACNS; Chief Editor: Selim R Benbadis, MD  more...
  • Print
Answer

Answer

The EOG tracks eye motion via changes in electric potential when the positive anterior aspect of the eye changes position relative to the negative posterior aspect. Recommended lead placement includes one lead placed 1cm below the left outer canthus and 1cm above the right outer canthus. During any eye movement, the cornea (positive) moves toward an electrode, while the fundus (negative) moves away from the same electrode. When the eye is not moving there is no net change in potential and the eye leads do not record a signal.

Electro-oculogram. During any eye movement, the co Electro-oculogram. During any eye movement, the cornea (positive) moves toward one electrode, while the fundus (negative) moves away from the same electrode. When the eye is not moving, the change in relative position is zero, and the eye leads do not record a signal. Conjugate eye movements thus cause out-of-phase EOG deflections.

Slow rolling eye movements are recorded as long gentle waves, while rapid jerking movements are represented by sharply contoured fast waves. Blinking of the eyes produces rapid vertical movements. Eye movements during drowsiness and stage N1 sleep may be irregular or gently rolling. In deeper stages of sleep macro eye movements cease altogether but regain activity during periods of REM.


Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!