About Visual Field Loss

What is visual field loss?

The visual field is the entire space that a person can see around them without moving their eyes. If areas of the brain that are involved in processing vision are impaired, then visual field loss can result. The field loss can be whole or partial. If you have this sort of visual field loss, you are unlikely to see it as an area of darkness in your visual field. Instead, the missing visual field is simply not there. In the same way that we cannot usually see behind us without moving our head and eyes.

What is hemianopia?

We refer to a loss of half the usual visual field, as seen through both eyes, as hemianopia. It can occur if only one side of the brain’s visual processing system is impaired. This could happen after a stroke. The brain’s visual processing system is organised in such a way that we can predict patterns of visual field loss from the location of brain injury. For example, an acquired injury on the left side of the brain’s visual processing system can lead to a right-sided hemianopia, and vice versa. Importantly, hemianopia is not always complete and some of the affected half of the visual field may still have visual function.

What is cerebral vision impairment?

Cerebral vision impairment (CVI) is an umbrella term used to describe a spectrum of brain-based vision difficulties. Approximately 1 in 6 children diagnosed with CVI have hemianopia. As many as 1 in 2 have other forms of visual field loss such as constricted visual fields. A common feature of CVI in some young people with conditions such as cerebral palsy is lower visual field loss. Additionally, seizure activity caused by conditions such as epilepsy can also produce persistent visual field loss.

Sign in

Lost password?

Forgot Password

Sign in


Click here to register

Verification error

It looks like your account is awaiting verification.

Contact us

Incompatible Screen Size

The size of your game window suggests you're playing on a mobile platform. Unfortunately this game isn't playable on devices with small screens.

Have you tried maximising the size of the window?

You can still access the site and register an account, but the game can only be played on a desktop computer that has a mouse.

Sign inClick here to register

Please Register to Play Eyelander

Are You:


An adult aged 18 years or older

Who wants to take part in research while they play Eyelander?


A parent or legal guardian

Of a young person or child who wants to take part in research while they play Eyelander?


Not interested in participating in research

But still want to play Eyelander?