Researchers use imaging technique to visualize effects of stress on human brain

Method tracks water molecules in blood

The holiday season is notorious for the emotional stress it evokes. Now, researchers at the University of Pennsylvania School of Medicine have come up with a non-invasive way to see the effects of psychological stress in an area of the brain linked to anxiety and depression. This research has important implications for how practitioners treat the numerous long-term health consequences of chronic stress.

In the study, which is reported in the Nov.21 online edition of the Proceedings of the National Academy of Sciences, researchers used functional magnetic resonance imaging (fMRI) to detect an increase in blood flow to the prefrontal cortex in individuals subjected to stress. Further, the increase remained even when the stressor was removed, suggesting the effects of stress are more persistent than once thought.

Whereas most previous fMRI studies have relied on indirect measures of cerebral blood flow, the Penn team, led by John A. Detre, measured blood flow directly, using a technique called arterial spin labeling. The technique is non-invasive, relying on magnetically “tagging” the water molecules in subjects’ blood.