What Is Peripheral Vision?

Peripheral vision is our ability to see out of the corner of our eyes. This means that we're able to see things outside of our direct line of vision without having to turn our heads: a skill that comes in handy throughout our waking hours, even when we don't realize it.

When there's a problem with our peripheral vision, it means that it takes more effort to see what's around us; this may result in tripping, falling, or other accidents.

Understanding Peripheral Vision

There are two main types of vision that we use every day, usually without thinking about it. These include:

• Central vision: This allows us to see what's going on directly in front of us, and typically, in clear detail (as long as we're wearing corrective lenses if we need them)
• Peripheral vision: This is what we can see out of the corners of our eyes, without having to turn our head or neck.

Peripheral vision allows us to get a much more complete view of our surroundings. In fact, if you've ever heard someone described as "having blinders on," that's a reference to the blinders worn by horses. These flaps attached to a horse's bridle block their peripheral vision, only allowing them to see what's directly in front of them, but nothing on the sides of their path.

Of course, when the term is used in relation to a person, it's figurative; meaning that they have a limited view on something and ignoring (either deliberately or unconsciously) other perspectives around them. So when we're talking about our literal peripheral vision, it's referring to being able to see what's going on out of our direct line of vision.

Causes of Peripheral Vision Loss

When someone experiences a loss of their peripheral vision, it is sometimes referred to as "tunnel vision." To get a better idea of what is going on in an eye with peripheral vision loss, we must look to the two types of cells in the retina that respond to light:

• Cones: Most of the cones are located in the center of the retina (also known as the macula) and allow us to see details and colors.
• Rods: These are in charge of our peripheral and night vision, and are located throughout the rest of the retina.

So when someone has an eye condition that impacts the rods' function, that could lead to the loss of their peripheral vision—even if their cones are still fully operational.

Signs of Peripheral Vision Loss

Loss of peripheral vision can happen gradually—to the point where a person doesn't notice the onset—or suddenly, in which case it can be alarming and scary. Though in some cases (especially when the vision loss is gradual), people may not notice any signs that they're living with a limited view. But in other cases, there are a variety of signs that are hard to miss, including:

• Tripping
• Having trouble walking in the dark
• Difficulty driving
• Reading much slower than usual
• Shimmers of light followed by tunnel vision lasting 10 to 20 minutes

Conditions That May Result in Peripheral Vision Loss

Unless it is the result of an injury, the loss of a person's peripheral vision is typically a symptom of an eye condition. These can range from something minor and temporary, to more serious conditions, including:

• Vitreous floater
• Ocular migraine
• Optic Neuritis
• Glaucoma
• Stroke
• Retinitis pigmentosa
• Retinal detachment 
• Pituitary tumor
• Carotid artery disease
• Cytomegalovirus retinitis
• Diabetic eye disease
• Diabetic retinopathy
• HIV/AIDS
• Idiopathic intracranial hypertension
• Ischemic optic neuropathy
• Low vision
• Pigment dispersion syndrome
• Retinal artery occlusion
• Stickler Syndrome
• Brain aneurysm

How to Test Peripheral Vision

A person's peripheral vision is tested during the visual field test component of a comprehensive eye exam with their optometrist or ophthalmologist.

"Visual field" refers to the width of the area a person can see while focusing on a central point, so testing it gives the healthcare provider a better idea of a patient's peripheral vision capabilities. It's one of the many reasons why it's so important to get regular eye exams. When the healthcare provider has your visual field baseline, they can compare future tests to it in order to see if your vision has gotten worse over time.

The most common way to test someone's peripheral vision is with a confrontation visual field test. During this part of the exam, the patient will be asked to look directly at an object in front of them—like the healthcare provider's nose or their headgear—while one eye is covered. While continuing to stare straight ahead, the healthcare provider will hold up different numbers of fingers (or something similar) in the patient's peripheral vision and ask them what they're able to see. This will help the healthcare provider assess the quality of their peripheral vision and if it's lower than expected, it could be a signal that further testing might be needed.

When to See a Healthcare Provider

If you lose your peripheral vision temporarily—as a result of a floater or ocular migraine, for example—and this is something that you've previously discussed with your healthcare provider, follow any instructions they gave you then. In any other situation, if you've lost your peripheral vision, it's important to see a healthcare provider as soon as possible, as it could be the symptom of a serious underlying condition.

Coping With Peripheral Vision Loss

When someone loses their peripheral vision, the primary way to cope is by making adjustments in:

• Habits
• Lifestyle
• Surroundings

If a loved one loses their peripheral vision, it may be tempting to try to do everything for them to make their life easier. But in reality, you're making it more difficult for them to establish their independence and get used to taking care of themselves.

The person who has lost their peripheral vision has to get used to having to turn their head to see things they could previously do without the extra effort.

It's helpful for the person to go through their own house and do what they can to make sure their pathways are clear, and there aren't any other obstacles in their way.

Of course, the decision of how to correct your vision comes down to more than peripheral vision, but it's something to keep in mind and discuss with your eye healthcare provider.

A Word From Verywell

Having any sort of problem with your eyes can be unsettling, and losing your peripheral vision is no exception. Because it is a symptom of a variety of other medical conditions—including some that are very serious—it's important to seek medical attention right away if you suddenly lose your peripheral vision. And because it can also be a gradual process, be sure to keep up with your regular eye exams, especially as you age.