Here's the most interesting part (for most of us): Since the original study included cognitive tests, the scientists compared the data and saw that people with the virus living in their throats processed visual information about 10% slower than people without the virus — and this difference couldn't be explained by other factors like age, sex, race, socioeconomic status, education, place of birth, or smoking status.
The specific visual information tests where a difference was shown included things like drawing a line that connected numbers in sequence that had been scattered on a page. People with the virus also seemed to have a shorter attention span.
To investigate whether the virus might be the cause of that change in visual processing and attention, the researchers then injected mice with the same virus.
Six weeks later, the group of mice with ATCV-1 took about 10% longer to navigate a maze, and they also spent about 20% less time exploring new environments.
The infected mice also showed more than 1,000 gene changes in the parts of the brain that are usually considered essential for memory and learning.
... "There's more and more studies showing that microorganisms in your body have a bigger influence than anything anyone would have predicted," the paper's senior author, James Van Etten, a University of Nebraska-Lincoln plant pathologist, told Healthline.
Read more: http://www.businessinsider.com/algae-virus-may-be-changing-cognitive-ability-2