Genetic research, too, will be needed to find out why bipolar brains grow more than the usual allotment of such cells. Bipolar disorder I has a strong but still unknown tie to DNA; studies of identical twins show that if one twin has it, the other has an 80 percent chance of having it, too. Zubieta is hopeful that genetic markers will one day be found that can help people know their risk of developing bipolar disorder.
A combination of both genetic research and neuroimaging studies would help define both the genetic components of this illness, and their relationship with the expression of specific brain chemical markers in specific patients.
The University of Michigan is launching a new trial that will enroll patients who have just been diagnosed with bipolar disorder, and those with a family history of the disease that puts them at higher risk.
"The reality is that we still have only sketches of what is going on in these brains, what the basic changes are, and how they are related to the course of illness," Zubieta says. "We need to look farther."
The study was funded by the University of Michigan's General Clinical Research Center, by the National Alliance for Research on Schizophrenia and Depression, and by the Mental Illness Research Association's Arthur Forrest Tull II Research Fund.
