Ocular artifacts in EEG and event-related potentials. I: Scalp topography.

摘要: The ocular artifacts that contaminate the EEG derive from potential difference between cornea and fundus of eye. This corneofundal or corneoretinal can be considered as an equivalent dipole with its positive pole directed toward cornea. shows a steady DC approximately +13 mV relative to forehead. Blink potentials are caused by eyelids sliding down over positively charged eye-movements result changes in orientation corneo-fundal potential. scalp-distribution described terms propagation factors--the fraction EOG signal at periocular electrodes is recorded particular scalp location. These factors vary location electrode. Propagation for blinks upward significantly different.