Investigators plan to enroll 50 subjects at Wills Eye Hospital without any eye diseases.
Participants will undergo a complete eye examination to determine eligibility, including visual acuity testing, intraocular pressure (IOP) in millimeters of mercury (mmHG), and visual field (VF) testing.
Participants will then be tested with Diopsys NOVA™ PERG \& FERG systems. For both tests, two electrodes are placed on the skin underneath each eye below the eyelashes. Participants' skin will be cleaned before electrodes are placed. A small amount of gel will be placed on skin where electrodes are placed for testing. Electrical responses are recorded with electrodes in response to visual stimuli.
