Researchers have been progressively gaining fresh and significant insights regarding the impact of COVID-19 on the body and brain while the epidemic has been in the rearview mirror for more than 18 months.
These discoveries have raised worries about the coronavirus’s long-term effects on biological processes such as aging.
My previous study as a cognitive neuroscientist focused on determining how typical brain changes associated with aging affect people’s capacity to think and move, particularly in middle age and beyond.
However, as further data emerged that COVID-19 could harm the body and brain for months or longer after infection, my research team was intrigued in learning more about how it can affect the natural aging process.
EXAMINING THE BRAIN’S REACTION TO COVID-19
An early yet large-scale study of brain abnormalities in people who have experienced COVID-19 garnered a lot of interest from the scientific community in August 2021.
The researchers used data from the UK Biobank, which has brain imaging data from over 45,000 people in the United Kingdom dating back to 2014.
This means that all of those persons had baseline data and brain imaging before the epidemic, which is critical.
The researchers evaluated the brain imaging data before bringing people who had been diagnosed with COVID-19 back for more examinations.
They compared COVID-19 survivors to non-survivors, closely matching the groups based on age, sex, baseline test date, and study site, as well as common illness risk factors such as health characteristics and socioeconomic level.
The researchers discovered significant variations in the grey matter between those who had been infected with COVID-19 and those who had not.
Gray matter is made up of the cell bodies of neurons that process information in the brain.
The thickness of grey matter tissue in the frontal and temporal lobes of the brain was reduced in the COVID-19 group, which was different from the typical patterns seen in the group that hadn’t received COVID-19.
Gray matter volume and thickness change over time as people age in the general population, but the alterations in those who had been infected with COVID-19 were larger than typical.
Surprisingly, when the researchers separated the people who had severe enough sickness to necessitate hospitalization from those who had milder COVID-19, the outcomes were the same.
That is, even when the condition was not severe enough to need hospitalization, persons infected with COVID-19 showed a reduction of brain volume.
Finally, researchers looked into changes in cognitive performance and discovered that people who had COVID-19 were slower at processing information than those who had not.
While we must exercise caution in interpreting these findings while they await formal peer review, the huge sample size, pre-and post-illness data in the same participants, and rigorous matching with those who had not been exposed to COVID-19 have made this exploratory research extremely important.
WHAT DO THESE BRAIN VOLUME CHANGES MEAN?
One of the most prevalent symptoms reported by persons infected with COVID-19 early in the epidemic was a loss of taste and smell.
Surprisingly, the brain regions affected by COVID-19 are all associated with the olfactory bulb, a structure near the front of the brain that transmits scent signals from the nose to other parts of the brain.
The olfactory bulb is connected to temporal lobe areas.
Because the hippocampus is located in the temporal lobe, it is frequently discussed in the context of aging and Alzheimer’s disease.
Given its significance in memory and cognitive processes, the hippocampus is anticipated to play a crucial role in aging.
The sense of smell is especially significant in Alzheimer’s research since some evidence suggests that those who are at risk for the disease have a diminished sense of smell.
While it is far too early to draw any conclusions about the long-term effects of these COVID-related changes, the possibility of a link between COVID-19-related brain changes and memory is intriguing – especially considering the regions implicated and their relevance in memory and Alzheimer’s disease.
VISIONING THE FUTURE
These discoveries raise several crucial but unsolved questions: What do these COVID-19-induced brain alterations signify for the aging process and pace? Is it true that the brain recovers to some extent from viral infection over time?
These are active and open research fields, some of which we are beginning to pursue in my laboratory as part of our ongoing brain aging study.
Our research shows that the brain thinks and processes information differently as people age.
In addition, we’ve noticed changes in how people’s bodies move and how they develop new motor abilities throughout time.
Several decades of research have shown that older persons have a tougher time digesting and manipulating information – such as updating a mental grocery list – but that their knowledge of facts and language remains relatively unchanged.
We know that older persons can learn new motor abilities, but they do so at a slower rate than young adults.
When it comes to brain anatomy, persons over the age of 65 often witness a shrinking of the brain.
This reduction is not limited to a single location. There are differences in many areas of the brain.
Due to the loss of brain tissue, there is usually an increase in cerebrospinal fluid, which fills the hole.
Furthermore, in older adults, white matter, the insulation on axons (long cables that transport electrical impulses between brain cells), is less intact.
As life expectancy has risen in recent decades, more people are living longer lives.
While the desire is for everyone to live long and healthy lives, even in the best-case scenario of aging without sickness or disability, changes in how we think and move occur as we become older.
Understanding how all of these puzzle pieces fit together can help us decipher the secrets of aging and improve the quality of life and function of the elderly.
And now, in the context of COVID-19, it will assist us in determining the extent to which the brain may heal following sickness.
the author : Jessica Bernard is an associate professor at Texas A&M University.
Read More: https://mysteriousofscience.com/new-according-to-the-cdc-people-who-have-experienced-covid-should-still-get-vaccinated/ https://mysteriousofscience.com/new-covid-19-cases-in-the-us-rise-60-due-to-under-vaccination/
