At-home brain speed tests bridge cognitive data gaps

Online tests of women’s reaction times offer insights into cognitive function and could help fill data gaps on early cognitive problems, potentially shedding light on dementia development later in life, finds a new study led by researchers at UCL and other universities.

The new paper, published in BMJ Open, finds that online tests can be an easy and effective way for women in their 40s and older to volunteer for dementia prevention research from their homes instead of visiting clinics. It shows that these tests can provide researchers with useful data about people’s cognitive functions by testing their reaction times.

Lead author Dr. Gareth Hagger-Johnson (UCL Geography) said, “Women have long been under-represented in healthy aging research, despite making up more than half the population. We developed an easy way to measure cognitive function in the home, without the need for individuals to travel to clinics or receive home visits. Our research shows that testing of cognitive function in the home is largely acceptable, easy and convenient.”

Measuring a person’s reaction time is the simplest way to measure their cognitive function. Although reaction time is not currently used to screen for problems with cognitive function, existing research shows that slower reaction times could predict future cognitive decline and dementia.

To specifically reach women for the study, the researchers drew upon data collected from participants in the UK Women’s Cohort Study, a longitudinal study originally designed to assess nutritional health, which has expanded to track other components of women’s health. The researchers drew on data collected from 2010 to 2011 during a follow-up study of 768 participants aged 48 to 85.

The online test measured users’ reactions on their home computers by having them correctly tap a number key as quickly as possible in response to the digit appearing on screen. The users also filled in an online questionnaire about their health literacy, education level, overall health and other traits. Feedback from the tests indicated that the participants mostly found the task easy and not stressful. Distracting pets and internet connectivity issues were the main concerns raised by participants.

Study limitations

Despite the overall positive responses, the researchers caution that bias may be introduced owing to volunteer effects. Each higher level of education increased the likelihood of volunteering by about 7%. Similarly, women who reported themselves as “high” intelligence were 19% more likely to take the test than those who said they were “average” intelligence. Younger women were more likely to try the online tests, with estimated participation rates dropping from 89% at age 45, to 44% at age 65.

Dr. Hagger-Johnson added, “Although it is clear that web-based testing of cognitive function is valuable to researchers, it’s important that we understand the limitations of unsupervised testing in the home. More effort needs to be made to reach vulnerable adults who do not use digital technologies regularly.”

One surprising finding was that women who said they had lower health literacy made fewer errors in the reaction time test. The researchers say this might be because they took longer to decide what the correct answer was, a pattern previously observed among older adults compared to younger adults.

The study was conducted in conjunction with researchers from City St George’s, University of London, University of Leeds and Heriot-Watt University.