Long-term memory problems after Covid-19: Comprehensive study confirms specific cognitive deficits

COVID-19 is associated with acute and long-term cognitive impairment, including memory and concentration deficits, as well as neuropsychiatric symptoms such as anxiety and depression. However, the mechanisms underlying these cognitive and affective changes are still largely unknown. A comprehensive study by SRH University impressively shows that Covid-19 disease can result in long-lasting and specific memory impairments. The results were recently published in the renowned journal Scientific Reports.

COVID-19 leaves traces - even in the brain

The research group analysed the cognitive functions of over 1,400 participants and was able to prove that the memory for distinguishing similar memories is particularly affected. This ability is largely controlled by the hippocampus, a central memory region of the brain.

The study analysed people who had already been infected with SARS-CoV-2 compared to a control group with no previous infection. The participants, aged between 18 and 90, completed a series of digital tests to assess specific aspects of their cognitive performance. This revealed significant deficits in what is known as mnemonic discrimination performance, i.e. the ability to distinguish between similar memories. This specific memory impairment occurred regardless of factors such as age, education, stress or depression. In contrast, other cognitive abilities, such as cognitive flexibility or general memory, remained largely unaffected.

"For the first time in a large sample, our results clearly demonstrate a specific memory impairment following COVID-19 disease that cannot be explained solely by psychological stress or general physical exhaustion," says Prof Dr Patric Meyer, Professor of General and Neurocognitive Psychology at the Heidelberg Campus of SRH University and head of the study.

Evidence of disturbed neurogenesis

The scientists suspect that inflammatory reactions in the brain, which often occur in connection with COVID-19, impair the formation of new nerve cells in the hippocampus. This could explain why those affected still struggle with cognitive impairment months or even more than a year after their infection - a typical feature of long COVID.

The findings of the study could help to better understand long-term cognitive symptoms of COVID-19 and to develop targeted rehabilitation programmes.

Publication

The study "Insights on the neurocognitive mechanisms underlying hippocampus-dependent memory impairment in COVID-19" was published in Scientific Reports on 20 June 2025.