Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Researchers from the University of Oxford have used data from UK Biobank participants to look at changes to the brain on average 4.5 months after mild SARS-CoV-2 infection.

3D rendering of coronavirus

The findings, published in Nature, reveal tissue damage and greater shrinkage in brain areas related to smell. This new insight into the damaging effects of COVID-19 will contribute to our overall understanding of how the disease spreads through the central nervous system. Whether these effects persist in the long term, or are partially reversed, requires further investigation.

Research has already shown that COVID-19 may cause brain-related abnormalities, but most studies have focused on hospitalized patients with severe disease, and have been limited to post-infection data. The effects of SARS-CoV-2 on the brain in milder (and more common) cases were unknown until now, and investigating these cases could reveal possible mechanisms that contribute to brain disease or damage.

Professor Gwenaëlle Douaud and colleagues investigated changes in the brains of 785 participants in UK Biobank, a large-scale biomedical database and research resource. Participants were aged 51–81 and underwent two brain scans, on average 38 months apart, as well as cognitive tests. A total of 401 participants tested positive for infection with SARS-CoV-2 between their two scans, of whom 15 were hospitalised. The remaining 384 individuals, who did not get infected, were similar to the infected group in age, sex, and many risk factors, including blood pressure, obesity, smoking, socio-economic status and diabetes.

The study, led by the Wellcome Centre for Integrative Neuroimaging at the University of Oxford, identified a number of effects, on average 4.5 months following infection, including a greater reduction in grey matter thickness in the regions of the brain associated with smell (the orbitofrontal cortex and parahippocampal gyrus). UK Biobank participants who had COVID-19 also displayed evidence of greater tissue damage in regions connected with the primary olfactory cortex, an area linked to smell, and a reduction in whole brain size. These effects ranged from 0.2 to 2% additional change compared with the participants who had not been infected.

Read the full story on the University of Oxford website

Similar stories

New evidence for how our brains handle surprise

A new study from the Bruno Group is challenging our perceptions of how the different regions of the cerebral cortex function. A group of ‘quiet’ cells in the somatosensory cortex that rarely respond to touch have been found to react mainly to surprising circumstances. The results suggest their function is not necessarily driven by touch, but may indicate an important and previously unidentified role across all the major cortices.

Language learning difficulties in children linked to brain differences

A new study using MRI has revealed structural brain changes in children with developmental language disorder (DLD), a common but under-recognised difficulty in language learning. Children with DLD aged 10-15 showed reduced levels of myelin in areas of the brain associated with speaking and listening to others, and areas involved in learning new skills. This finding is a significant advance in our understanding of DLD and these brain differences may explain the poorer language outcomes in this group.

The Gene Therapists Headline at Glastonbury 2022

Rosie Munday writes about her experience taking science to the masses at the Glastonbury Festival.

New research reveals relationship between particular brain circuits and different aspects of mental wellbeing

Researchers at the University of Oxford have uncovered previously unknown details about how changes in the brain contribute to changes in wellbeing.

Night-time blood pressure assessment is found to be important in diagnosing hypertension

Around 15% of people aged 40-75 may have a form of undiagnosed high blood pressure (hypertension) that occurs only at night-time. Because they do not know about this, and therefore are not being treated for it, they are at a higher risk of cardiovascular disease such as stroke, heart failure, and even death, suggests new research from the University of Oxford published in the British Journal of General Practice.