For several neurodegenerative diseases, scientists identified which cell types exert a person’s inherited risk. In Alzheimer’s, it’s microglia; in Parkinson’s, it’s dopaminergic and enteric neurons—and oligodendrocytes.
Chemicals and particulates may slip across the blood-brain barrier or travel up olfactory nerves to directly affect brain cells. What are the consequences for cognition?
Growing evidence suggests exposure to air pollution increases risk of brain damage and dementia. More definitive research is needed.