Findings of “troubling brain changes” among people who lost smell from having “covid”.

https://www.nature.com/articles/s41598-024-69772-y

https://www.psypost.org/scientists-discover-troubling-brain-changes-in-covid-19-patients-who-lost-sense-of-smell/

This is an interesting article.

CAVEATS: this study ran well into vaccination periods, so there is commingling of vaccinated and unvaccinated people who caught covid in this study. So an assumption of it being purely due to covid infection would be difficult as the water is muddied post vax. Second, there are many who question what covid was, so this article is going with the assumption it was a virus.

A study that ran from February 2020 into May 2023 looked at brain changes among people who had loss of smell. And, it appears to affect people more often who had a mild version of the illness, who were not hospitalized. Those who had a mild cold-like or flu-like version and treated it at home with no major medical interventions.

“Many patients, even those with mild cases, reported cognitive issues such as memory problems, confusion, and difficulties with concentration, which raised concerns about the virus’s effects on the brain. Neurological symptoms like headaches, brain fog, and loss of smell emerged as common issues for COVID-19 survivors.”

“To investigate these possible brain changes, the research team recruited 100 adults in Santiago, Chile, who had recovered from respiratory infections between February 2020 and May 2023. The final sample included 73 participants who had confirmed cases of COVID-19 (the remaining participants had respiratory infections caused by other agents, as confirmed by multiple negative PCR tests). The team used a combination of tests and brain scans across two sessions to assess these participants’ brain function and structure.” The study excluded anyone with brain health issues or neuropsychiatric concerns. (ie no one with Parkinson’s, Alzheimer’s, significant psychiatric illness, etc).

“In behavioral tests, participants with a history of anosmia displayed more impulsive decision-making compared to those who did not lose their sense of smell. These individuals tended to change their choices more rapidly after receiving negative feedback, particularly in tasks requiring them to learn and adapt to changing probabilities of rewards. While this impulsivity led to higher earnings in decision-making tasks that involved rapidly shifting conditions, it also highlighted an alteration in how their brains processed rewards and risks.”

“Functionally, patients with a history of anosmia showed decreased brain activity during decision-making tasks in regions associated with evaluating choices, including the lateral prefrontal cortex and temporoparietal regions.”

“On the structural side, brain scans showed thinning in specific regions of the brain in participants with a history of anosmia. Most notably, these changes were observed in the parietal areas of the brain, which are responsible for processing sensory information and managing spatial awareness. The thinning in these areas could indicate long-term structural changes in the brain caused by the virus in individuals who experienced loss of smell.”

“Additionally, these participants exhibited decreased white matter integrity, particularly in white matter tracts that connect important brain regions. White matter plays a crucial role in facilitating communication between different parts of the brain, and disruptions in these connections could lead to a range of cognitive impairments.”

This study needs to be performed on a much larger scale, among other countries. It needs to include those who were sick with any respiratory illness including covid. It needs to be divided between people who were vaccinated and not. There is much work to be done, but it does highlight what I see on a daily basis: people reporting brain fog, concentration issues, and fatigue. “Something” happened. We need to know more.