Respiratory impacts from COVID-19 are well-known, but people also commonly experience cognitive dysfunction, often called brain fog, which can last for months after initial infection. It’s frequently described as difficulty remembering, focusing, and completing daily tasks. 

Now, the impact of COVID-19 on memory has been demonstrated by U.K. investigators using a new assessment tool.*

What the researchers did

The scientists, from Hull York Medical School, University of York, aimed to learn more about short-term memory loss associated with COVID-19 through an anonymous online survey. As reported in the journal PLoS ONE, the survey included a quick, game-like memory quiz called the COVID-19 Online Rapid Objective Neuro-Memory Assessment (CORONA). The study lasted from December 8, 2020 to July 5, 2021, and involved:

• More than 5,400 adults aged 18 years and older 
• 68.6% of respondents who’d never had COVID-19, and 31.4% who did

What they found

There were several principal findings.

• There was a “clear” significant drop in memory scores across all COVID groups (those with a positive COVID-19 test, self-reported disease, and people hospitalized) versus healthy controls.
• Looked at more closely, the combined memory score for all COVID groups was significantly less than that of healthy controls in every age group from 25 years and up, but not those 18-24 years old, the youngest age group.
• Memory scores were found to gradually increase over a 17-month period following the COVID illness, while those who continued experiencing COVID symptoms saw further memory loss.

Factors significantly affecting memory scoring were:

• Age
• COVID-19 status
• Elapsed time from COVID infection
• Lingering COVID symptoms (i.e., Long COVID)

Average completion time for the survey and quiz was 8.84 minutes—relatively rapid, say the authors. Compared to prior “lengthy surveys with multiple tasks,” they say they wanted a tool that would appeal to a broad audience and rapidly assess COVID’s impact on working memory specifically.

A form of short-term memory, working memory stores and retrieves information as we perform essential tasks, like conversing, problem-solving, or reading.

What it means

“What the study demonstrates is that COVID-19 negatively impacts working memory or short-term memory function, but only in adults aged 25 years and over,” said first author Heidi Baseler, Ph.D., Senior Lecturer in Imaging Sciences. “While the survey suggests that memory function with COVID-19 can recover over time, our findings indicate that those with ongoing symptoms may continue to experience difficulty with short-term memory.”

The researchers say that the study will help clinicians assess COVID-related memory impairment, especially since the survey/quiz can be completed quickly to accommodate patients with limited attention spans. They suggest that the tool could also be effective for assessing people with other memory-related disorders, like dementia.

*University of York. (2022, November 30). New research shows that COVID-19 negatively impacts memory function. MDLinx. https://www.mdlinx.com/news/new-research-shows-that-covid-19-negatively-impacts-memory-function/6st9bm8T7LtMhdPYPGmt3M