Covid-19 can have a negative effect on short-term memory function and working memory, a new study suggests. Researchers say memory function can recover over time, but those with ongoing Covid symptoms may continue to experience difficulties.
The team, from Hull York Medical School, used an online anonymous survey which included a memory quiz. Many people with Covid-19 said they experience what is often described as “brain fog” – problems remembering, concentrating, and performing daily tasks.
More than 5,400 participants took part in the study between December 8, 2020 and July 5, 2021, with 68.6% of respondents never having Covid and the other 31.4% at one stage infected. Researchers said it was clear from the analysis that there was a significant reduction in memory scores in all Covid-19 groups (self-reported, positive-tested and hospitalised) compared to those who had not been infected.
The factors which significantly affected memory scores were found to be Covid-19 status, age, time post-Covid and whether individuals were experiencing ongoing symptoms. Memory scores for all Covid groups combined were significantly reduced compared to the non-Covid group in every age category 25 years and over, but not for the youngest age category of 18-24.
The study, published in Plos One, also found that memory scores gradually increased over a period of 17 months post-Covid. However, those with ongoing symptoms continued to show a reduction in memory scores. Dr Heidi Baseler, senior lecturer in imaging sciences at Hull York Medical School, University of York, who was first author on the study, said: “Although it is well known that Covid-19 affects the respiratory system, it is perhaps less well known that it can also have neurological consequences and affect cognitive function, such as memory.”
Dr Aziz Asghar, senior lecturer in neuroscience at Hull York Medical School, University of Hull, and co-author on the study, said: “We wanted to develop a survey which would engage as wide an audience as possible, to allow us to rapidly assess the impact of Covid-19 specifically on working memory function.
Dr Baseler added: “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.
“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.”
Working memory is a form of short-term memory. It is essential for daily life and allows us to store and retrieve information while performing a task such as problem solving, reading, and having a conversation.