Brain MRI Reveals Different Cellular Activity In Bipolar Disorder

Abnormal cellular activity in two parts of the brain may be linked to bipolar disorder, say University of Iowa scientists.

The team that scanned a small sample of 15 bipolar patients found differences in metabolic byproducts between those suffering from the disease and 25 control subjects. Using an MRI technique called quantitative high-resolution T1 rho mapping, they uncovered a different signal coming from the brain’s white matter and in the cerebellum. The signal could be the result of higher acidity or a reduced concentration of glucose.

“Our study was essentially exploratory. We didn’t know what we would find,” said Casey Johnson, a postdoctoral researcher and one of the authors of the study published last week in the journal Molecular Psychiatry. “The majority of bipolar disorder research has found differences in the frontal region of the brain. We found focal differences in the cerebellum, which is a region that hasn’t really been highlighted in the bipolar literature before.”

Bipolar disorder is a serious mental health condition that affects nearly 6 million Americans every year. Sufferers endure mood swings that bring them to the depths of depression and the irrational heights of mania. The MRI study found that patients taking lithium, the most common treatment prescribed for bipolar disorder, erased the differences the team found in the cerebellum of patients not taking the drug.

The new MRI technique is “really providing a new picture and new insight into the composition and function of the brain [in bipolar disease],” said psychiatry professor John Wemmie, who was the senior author of the study.

Wemmie, who studies the effect of changing acidity levels in the brain, has previously found evidence that suggest higher acidity is linked to panic disorders, anxiety, and depression.

“If lithium’s effect on the cerebellum is the key to its effectiveness as a mood stabilizer, then a more targeted treatment that causes the same change in the cerebellum without affecting other systems might be a better treatment for patients with bipolar disorder,” Wemmie said.

Top Image: Using an MRI technique that is sensitive to certain byproducts of cell metabolism, including levels of glucose and acidity, University of Iowa researchers discovered previously unrecognized differences in the brains of patients with bipolar disorder. The T1rho MRI scans showed brain regions of elevated signal in the 15 participants with bipolar disorder compared to the 25 participants who did not have bipolar disorder. The primary regions of difference are the cerebral white matter (yellow) and the cerebellum (red). Art courtesy of University of Iowa Carver College of Medicine.