There are many different conditions that can affect your vision. These conditions often interfere with the ability of light to pass from the eye to the brain. Yet several intriguing cases have been described that typically arose from selective traumatic injuries or strokes. Standard clinical tests commonly reveal spatially restricted blindness, also called scotoma, in the part of the visual field affected by the lesion.
With age, the eyes’ ability to stay lubricated starts to wane. This can leave eyes feeling irritated, sticky, dry, or gritty. The lens of the eye can become less elastic. Night vision may also start to suffer, which can pose problems when driving at night. In contrast, cataracts, macular degeneration, and diabetic retinopathy can rob you of your sight.
Healthcare providers can often prevent or correct many of these conditions and terms. The terms have been coined to describe a seemingly paradoxical clinical phenomenon that arises following injuries to the primary visual cortex.
Detached retina | A detached retina occurs when your retina tears away from the back of your eye and loses its blood and nerve supply. When it happens, you see flashing lights and black flecks followed by an area of blurred or absent vision. Without emergency treatment, vision in that area may be permanently lost.
Wet macular degeneration | The center of your retina is called the macula. Abnormal vessels may grow, causing blood and other fluid to leak into the macula. This is called wet macular degeneration. It causes blurriness and vision loss in the center part of your visual field. Unlike dry macular degeneration, this type can begin suddenly and progress rapidly.
Angle-closure glaucoma | Angle-closure glaucoma occurs when the drainage system within the eye is blocked. In this situation, the pressure inside the eye can go up very quickly causing redness, pain, and nausea. This is a medical emergency and requires treatments with eyedrops to open the angle, decrease the pressure, and decrease the inflammation. Many times a laser procedure, called laser iridotomy, is also required.
Aging | As you get older, your risk increases for vision-impairing conditions. Common disorders include cataracts (clouding of the eye lens) and age-related macular degeneration (AMD), a condition that causes loss or distortion of vision.
Damage | Injuries may cause a detached retina or a clouding of the cornea or lens. This damage can block light from passing through your eye and cause vision loss.
Development disorders | Sight problems such as amblyopia (lazy eye) occur when one or both eyes develop abnormally during childhood.
Disease | Diseases like glaucoma (increased fluid pressure in the eye) can damage the optic nerve. As a result, they impair the brain’s ability to turn electrical signals into images.
Infection | Infections in any part of the eye can affect your ability to see.
Refractive errors | Vision problems can occur when your eye doesn’t bend light properly. This issue may impair your eye’s ability to focus and cause unclear eyesight. Corrective lenses, such as glasses or contact lenses, can often improve your eyes’ ability to see clearly.
Stress | Stress can also cause blurred vision and, ironically, experiencing a vision problem can create more stress.” When a stressful moment occurs, pupils dilate allowing more light to enter the eye which can actually interfere with one’s vision. Too much light can actually result in blurriness.
High blood sugar | Very high blood sugar levels cause the lens of your eye to swell, which results in blurred vision.
Optic Neuritis | The optic nerve connects your eye and your brain. Inflammation of the optic nerve is called optic neuritis. It’s usually caused by an autoimmune reaction or early multiple sclerosis. Other causes are autoimmune conditions, such as lupus or an infection. Most often, it affects only one eye.
Temporal arteritis | Inflammation in the medium-sized arteries is called temporal arteritis. The vessels around your temples can be involved causing a throbbing headache in your forehead, but it can also cause your vision to blur or disappear.
Uveitis | The uvea is a collection of pigmented structures in the eye including the iris. An infection or autoimmune reaction can cause it to become inflamed and painful, which is called uveitis.
Call your doctor if you experience any of the following
- Change in iris color
- Crossed eyes
- Dark spot in the center of your field of vision
- Difficulty focusing on near or distant objects
- Double vision
- Dry eyes with itching or burning
- Episodes of cloudy vision
- Excess discharge or tearing
- Eye pain
- Floaters or flashers
- Growing bump on the eyelid
- Halos (colored circles around lights) or glare
- Hazy or blurred vision
- Inability to close an eyelid
- Loss of peripheral vision
- Redness around the eye
- Spots in your field of vision
- Sudden loss of vision
- Trouble adjusting to dark rooms
- Unusual sensitivity to light or glare
- Veil obstructing vision
- Wavy or crooked appearance to straight lines
Before information can be used in a meaningful way, it must first be attended to within the perceiver’s environment. However, how these stimuli are perceived must be examined in the context of evolutionary function in order to understand adaptive relevance to the human cognitive system. Take great care of this ability to efficiently attend to information within your environment as a vital cognitive skill that allows you to appropriately interact with the world.