An experiment showed that a brain wave test, lasting only three minutes, may reveal indicators of memory problems linked to Alzheimer’s disease years before clinical diagnosis is possible.

Researchers believe this test could be a low-cost tool for those who have difficulty obtaining a diagnosis and can be used in various settings, including homes, according to the British news agency PA Media.

The new test, called “Speedball,” was developed at the University of Bath and relies on measuring brain electrical activity by placing small sensors on the scalp. Patients are shown rapidly changing images while the brain’s automatic response is recorded.

The study, led by experts from the Universities of Bath and Bristol and published in the journal Brain Communications, included 52 patients with mild cognitive impairment—meaning a decline in memory or thinking skills—and 54 healthy elderly individuals.

The Alzheimer’s Society estimates that around 982,000 people suffer from dementia in the UK, but more than a third remain undiagnosed. The number is expected to rise to 1.4 million by 2040.