Using a set of glasses to simulate AMD, the participants scored much lower on the cognitive test involving reaction time tasks than without the glasses. There was no statistical difference with the verbal fluency tests when wearing the glasses.

UniSA doctoral candidate Anne Macnamara, who led the study, says that the results are a stark reminder that visual impairments, which affect an estimated 200 million people worldwide over the age of 50, unfairly affect cognitive scores when tests involve visual skills.

“A mistaken score in cognitive tests could have devastating ramifications, leading to unnecessary changes to a person’s living, working, financial or social circumstances,” Macnamara says.

“For example, if a mistaken score contributed to a diagnosis of mild cognitive impairment, it could trigger psychological problems including depression and anxiety.”

“People with AMD are already experiencing multiple issues due to vision loss and an inaccurate cognitive assessment is an additional burden they don’t need.”

UniSA researchers say that visual impairments are often overlooked in clinical and research settings, and this reduced vision was underestimated in up to 50% of older adults.

And since this figure is expected to increase as the population ages, it is critical that neurodegenerative researchers monitor vision when assessing people’s cognition.

“Mobile apps can now be used to overlay simulated visual impairments onto test materials when piloting their stimuli,” Macnamara says.

“Also, researchers can incorporate quick and simple screening tasks before getting people to do cognitive tests. Verbal tasks should always be part of the assessment, too.”

Source: Medindia