Eye flickering and flashing happens when the vision-related cerebral cortex or retinal photoreceptors are inappropriately activated, according to the University of Michigan Kellogg Eye Center. Several issues can cause this inappropriate activation, resulting in the patient's vision seeming to flicker and flash.
Aging
As we age our eyes, and their structures, age as well. When the vitreous ages, tugging can occur. The vitreous, properly called the vitreous humor, is the part of the eye that is clear and has a jelly-like substance that fills the eyeball behind the eye's lens. The tugging occurs when the vitreous becomes detached from the retina, as is normal in middle age, according to the University of Michigan Kellogg Eye Center. As the separation occurs, the retina is tugged on, resulting in the photoreceptors being stimulated. This stimulation, especially when the eyes are moved suddenly, causes the patient to see flickering or flashing.
Migraine
A migraine is a type of headache often described as more severe than a regular headache. Approximately 11 out of every 100 people experience migraines, according to Medline Plus. Visual symptoms are common with migraine headaches. In addition to flickering vision, patients can experience a temporary blind spot, eye pain, tunnel vision, blurred vision or seeing stars. Abnormal brain activity is what causes this type of headache. Several things can trigger this abnormal activity, such as certain foods, alcohol, bright lights, hormone level changes, exercise, missing meals, being exposed to smoke or smoking, allergic reactions, certain smells, sleep pattern changes, loud noises, emotional stress and physical stress.
Partial Seizure
Also referred to as a focal seizure, this seizure occurs when electrical activity in the brain is abnormally disturbed. Several symptoms are associated with this type of seizure, including changes in vision. Such visual changes can include blurred vision, blind spots, vision dimness and halos around lights, according to Medline Plus. Other visual symptoms can include forced turning of eyes and dilated pupils. These seizures are most often associated with epilepsy, a condition in which electrical signals are generated in the brain.
