It's no secret that breathing in polluted air on a regular basis can do a number on your heart and lungs. Now researchers from Ohio State University claim that air pollution can cause learning and memory problems, as well as depression.
The research, published this week in the journal Molecular Psychiatry, exposed mice to polluted air (fine particulate matter) that is comparable to what can be seen in major cities. After 10 months of exposure, the mice were given behavioral tests. In one test, mice placed in a brightly lit area were given two minutes to find an escape hole to a dark box (mice want to be in a dark environment rather than a light one) after a five-day training period. The pollution-exposed mice took longer to find the escape hole and were not as likely as their pollution-free counterparts to remember where the hole was later . These same mice were also more likely to exhibit depressive behaviors.
So what happened to the pollution-exposed mice? The researchers tested the hippocampal area of the mice, a region of the brain associated with depression, learning, and memory, and found that the pollution-exposed subjects had fewer dendrites , spines (dendrite projections that transmit signals between neurons), and diminished cell complexity--all the stuff you need for your hippocampus to work correctly.
This is not good news for humans. "The results suggest prolonged exposure to polluted air can have visible, negative effects on the brain, which can lead to a variety of health problems," said Laura Fonken, lead author of the study, in a statement. "This could have important and troubling implications for people who live and work in polluted urban areas around the world." We can't imagine the situation is much better for people who live near coal  plants and factories--even outside urban areas.
[Image: Flickr user eutrophication&hypoxia ]