Many individuals who lost their sense of smell when infected with COVID-19 show structural and functional brain alterations on imaging, according to new work published in Nature. Now, experts are concerned that the symptoms could be associated with long-term brain alterations. In a group of people who reported anosmia as one of their COVID symptoms, experts recently observed an association between the loss of smell and decreased functional activity during decision-making tasks, reduced cortical thickness and other neural measures.
Interesting study, but N=100, with only 73 having had COVID-19, is a rather small sample size. Hopefully this can be cited as a need for additional research with a larger group!
Brain imaging studies usually have low sample size https://www.sciencedirect.com/science/article/pii/S1053811920306509