We know that COVID-19 can affect our respiratory systems but it may also affect our brains.
Research from Baycrest’s Rotman Research Institute (RRI) and elsewhere shows that the COVID-19 virus can enter through one’s nose and attack the brain, resulting in long-term neurological symptoms, such as trouble thinking and memory loss. RRI scientists are now concerned that the lingering effects of COVID-19 can ultimately increase the risk of Alzheimer’s disease and other forms of dementia.
Patients who have had COVID-19 are experiencing brain-related symptoms, ranging from headaches to anxiety, depression, hallucinations and changes in smell and taste.
BRAIN STRUCTURE AND FUNCTION
A team of scientists at the RRI, led by Dr. Allison Sekuler, President and Chief Scientist at the Baycrest
Academy for Research and Education, and Sandra A. Rotman Chair in Cognitive Neuroscience at the RRI, has collaborated with colleagues at Sunnybrook Health Sciences to examine the effects of COVID-19 on brain structure and function.
In a small study, they conducted sensory, cognitive, and clinical assessments, along with electroencephalography (EEG) testing and magnetic resonance imaging (MRI) of the brain in 41 recovered COVID-19 patients and people who experienced COVID-like symptoms but tested negative.
Study participants were assessed at baseline and again several months later to detect whether brain
symptoms were present and whether they resolved or lingered. Preliminary EEG results showed peculiar brain wave patterns in COVID-19 patients several months later. Namely, these patterns were similar to those seen in people diagnosed with mild cognitive impairment, which can develop into dementia.
These results do not mean that everyone with COVID-19 will end up with dementia. However, they do
indicate the need for further research to determine whether the direct effects of COVID-19 on the brain increase dementia risk and ways to mitigate this.
The pandemic may also increase the risk of developing dementia in other ways. For example, physical
distancing and other public health measures may increase the risk of social isolation and depression,
which are linked to a heightened risk of dementia.
Dr. Rosanna Olsen, RRI Scientist, and Dr. Jennifer Ryan, RRI Senior Scientist, are conducting frequent
virtual check-ins with healthy older adults living in thecommunity to assess changes in their mental health, exercise routines, cognitive function and socialization levels, as well as their exposure to COVID-19.
Their work will increase our understanding of factors affecting older adults’ dementia risk. This research
can also identify ways to support older adults during the pandemic by helping them mitigate their
dementia risk and make the most out of life during these unprecedented times.
Dr. Donna Rose Addis, Baycrest’s Canada 150 Research Chair in Cognitive Neuroscience of Memory
and Aging and Senior Scientist at the RRI, and Dr. Shayna Rosenbaum, Adjunct Scientist at the
RRI and Professor and York Research Chair in the Faculty of Health’s Department of Psychology at
York University, are investigating the effects of the pandemic on people’s mental health and how this
may impact their ability to imagine the future.
People with depression are less able to imagine the future in detail. They may also experience the sense that their future is shortened, particularly during uncertain times.
In their Thinking Beyond COVID-19 study, Drs. Addis and Rosenbaum are surveying participants in 25
countries multiple times during the pandemic to observe changes in mental health and future
thinking. They are also examining whether imagining a post-pandemic future can be used as a method of increasing adherence to public health guidelines. This research will help inform policy to address these challenges during the pandemic and beyond.
There is still much to be learned about the effects of COVID-19 on the brain and how they may be
addressed. Fortunately, there are many things we can do to help protect ourselves and each other from COVID-19, like getting vaccinated, keeping a physical distance of at least two metres from others, wearing properly fitted masks, washing hands, and isolating if symptoms develop.