Have you ever believed that your mental functioning was “off” during a long period of time when you were under a lot of stress? Did you think it was all in your head, so to speak? Or, that it wasn’t real, but just in your imagination? Think again.

A recent study in the Proceedings of the National Academy of Sciences (2009 Jan 20; 106:912.) followed twenty healthy medical students for the month before and the month after their important exams, and compared them with twenty matched control students who were not taking exams or under stress. That the students preparing for exams were indeed under stress was confirmed by using a standard scale of measurement.  

After four weeks of stress, impairment was shown by MRI scan, and by testing, in the section of the brain known as the prefrontal cortex.  The specific function that was found to be impaired was that of “attention”, or the ability to prioritize mental tasks, to focus on them, and to shift the focus as the need arises. This impairment was not seen in the students who were not under stress.

Four weeks after the stress ended, the students were tested again. Those who had been under stress were no longer different from those who had not. This shows that brain function can change, and then change again. And shows that stress-induced changes are reversible.

This study confirms what we’ve thought for years: that chronic stress can indeed affect the brain so that it does not function as well as usual. And this research leads to the conclusion that we need to be on the lookout for stress-induced changes in our bodies, and that we need to de-stress in order to keep ourselves functioning well.

So, the next time you are under stress for a longer period of time than just a few days, and think that your mental functioning is not quite up to par, remember this study. It’s not all in your head (imagination)! Learn ways to de-stress. (See the prior blog)