Here is what got me spun up:
1. Helicobacter pylori, the main cause of stomach ulcers: Children infected with this ulcer-causing bacterium performed worse on IQ tests, suggesting a possible link between H. pylori infection and cognitive development.
H. pylori may contribute to cognitive impairment or Alzheimer's disease, according to a study published in the June issue of Psychosomatic Medicine. Compared with uninfected individuals, people who tested positive for H. pylori performed worse on cognitive tests, including ones assessing verbal memory. Some laboratory evidence indicates that H. pylori cells can escape the gut and sneak into the brain. There the cells aggregate with the amyloid proteins characteristic of Alzheimer's and instigate the buildup of plaque, suggests study co-author May Baydoun, a staff scientist at the National Institute on Aging. The National Institutes of Health estimates that about 20 percent of people younger than 40 and half of adults older than 60 are infected with the bacteria, which can be treated with antibiotics.
2. Lactobacillus helveticus and Bifidobacterium longum: Healthy human volunteers who consumed a probiotic mix of these bacteria exhibited less anxiety and depression.
3. Probiotic bacteria B. animalis subsp. lactis, Streptococcus thermophilus, L. delbrueckii subsp. bulgaricus, L. lactis subsp. lactis: Healthy women who consumed yogurt containing these bugs showed less activity in brain regions that process emotions and physical sensations. Researchers do not yet know whether these effects were beneficial; they also have not discovered the mechanism underlying the observed shift in brain activity.
[link to www.scientificamerican.com]