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 become impaired due to injury or other medical condition it can result in a partial or whole loss of the visual field. This visual field loss is not experienced as darkness but is simply not seen in the same way that we cannot see behind us without moving our head and eyes.

What is hemianopia?

Hemianopia is defined as a loss of half the usual visual field, as seen through both eyes. It can occur if one side of the brain has been affected by an injury such as stroke. Due to the way visual information is usually represented and transmitted in the brain an acquired injury on the left side of the vision processing centres in the brain can lead to a right-sided hemianopia, and an injury on the right side of the vision processing centres of the brain can lead to a left-sided hemianopia. 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 vision impairments caused by brain injury or dysfunction either sustained around the time of birth or acquired later in life.¬†Approximately 1 in 6 children diagnosed with CVI have hemianopia, and 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 caused by ‘dorsal stream dysfunction’. Seizure activity (e.g. caused by epilepsy) can also produce persistent visual field defects.

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?