BBC News reports that a University of Edinburgh study reveals that the brains of individuals with bipolar disorder shrink faster than expected.

Researchers based their research on MRI scans of 20 people with the bipolar disorder and an equal number in a control group. Over time everyone’s brain showed a loss of brain tissue, but individuals with the bipolar disorder showed significant loss of gray matter. Those who lost the greatest amount of gray matter were also the ones with the most episodes of mania and depression accompanied with the biggest decline in brain function.

What is not known is if the loss of gray matter is the cause or effect of the bipolar disorder. It may be that stress or genetic factors cause the brain shrinkage. Also, it could be that cycles between mania and depression result in the loss of gray matter. Either way the loss of brain tissue emphasis the importance of continued treatment for those with bipolar disorder.