1. EE 4BD4 Lecture 12 Electro-ocularogram EOG 1

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3. Other Theories Dipole is generated by a distribution of positive and negative charges in the retina only Signal results from eyelid moving over the eyeball (similar to blink artifact in EEG) Not a result of EMG of extra-ocular muscles 3

4. Extra-Ocular Muscles 4

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12. Utility of EOG Help in diagnosis of eye pathologies Important data  Saccadic movement parameters  Arden Ratio Identification of REM sleep Computer interface for the disabled 12

13. Design Considerations Electrodes (Ag-AgCl - drift free) Bandwidth (filtering) What about instrumentation or Op amp voltage offsets? AD 620 max voltage offset RTI = 125 µV Additional analog circuitry? 13

14. Offset Adjust Circuit 14