A recent study has discovered a link between abnormal circadian rhythms and neurotransmitter changes for those who have bipolar disorder. The study covered a three year period. McLean Hospital researchers determined that those with bipolar disorder exhibited changes in the neurons in the brain that help regulate stress and anxiety, and these changes appeared to result from abnormal circadian rhythms. According to Harvard Medical School psychiatry instructor and McLean’s Translational Neuroscience Laboratory assistant neuroscientist Harry Pantazopoulos, Ph.D, one of the study researchers and the lead author, “For more than 50 years, there’s been evidence that there’s something wrong with circadian rhythms in people with bipolar disorder, but there has been a huge gap in terms of what we understand about their brains and how altered circadian rhythms are contributing to their symptoms.”
It has long been suspected that abnormal circadian rhythms and bipolar disorder have some association or connection, this latest study just confirms this. Pantazopoulos explained “Growing evidence points to a key role for somatostatin, a neurotransmitter in schizophrenia and bipolar disorder. In the amygdala, a part of the brain involved in anxiety and stress, somatostatin plays an important role in the regulation of anxiety and depression, often co-occurring in these disorders. We eventually saw that people with bipolar disorder have a very strong decrease of this protein in the beginning of the day while people without a psychiatric disorder normally have an increase in this protein. The decrease of the protein correlates very strongly with the established severity of depression and anxiety symptoms in people with mood disorders, in the morning. Therefore, our findings point to potential neural correlates of circadian rhythm abnormalities associated with specific symptoms in bipolar disorder.”
