A new study, which was published in the journal Brain, is showing that people who are depressed or have bipolar disorder really do have fuzzy thinking. This fuzzy thinking or less sharp thinking often is occurring before the symptoms began, and now researchers have conducted a large study which shows this is indeed a real change in brain activity. The research was carried out by researchers at the University of Michigan Medical School and Depression Center.
The results of the study are also piecing together a puzzle that shows how depression and bipolar disorder are part of a class of mood disorders, instead of being unrelated. In terms of treatment, doctors will be able to transform how they treat bipolar and depressed patients by following the guidelines given to treat people with mood disorders.
In the study, 612 women were given tests, with two-thirds of these women experiencing depression or bipolar disorder, and 52 of the women also signed up for a brain scan. There were 150 healthy women in the study, with 266 women that had major depression, and 202 women who were bipolar but not in a manic state at the time. 17 healthy women, 19 depressed women, and 16 bipolar women decided to do the tests while inside of the scanner. The tests for those 52 women were given during the brain scan, which helped researchers look more in-depth at the changes taking place in the brain, and the differences that showed up on the scan. This was a pretty big mental health study compared to most other mental health studies, which means the results are even more validating than if a small sample group was used. The researchers took data from various University of Michigan studies, such as the Prechter Longitudinal Study of Bipolar Disorder, and only focused on the results of women so that gender would not be a factor in the results.
Women who had depression or bipolar disorder did just as bad on the tests, and these tests required a significant amount of concentration. The tests mostly asked them to react as quick as possible when certain letters were flashed on a screen, then there would be other random letters in between. The group was compared to a group who had no mental health issues, and it showed that there was a noticeable difference in terms of cognitive control. The women actually did score just as well on the test as the health non-mentally ill participants, however almost all of the bottom 5 percent was made up of women who had one of the two mood disorders.
The researchers then looked at the brain scans, and found that the women who had one of the two disorders had different levels of brain activity when compared to a healthy woman without mental health issues. There was a significant difference in a part of the brain known as the right posterior parietal cortex, which is where executive function takes place, such as memory and problem solving. The depressed women had higher activity in this area of the brain, while women who had bipolar disorder had lower levels of activity in this part of the brain. The results showed that there was the same dysfunction in terms of cognitive abilities, whether the women were bipolar or suffering major depression, and this is the same cognitive dysfunction that is seen in other women with mood disorders.
The results of the study support the theory that these two mental health issues fall under the same category as other mood disorder, and that most mental health issues are more similar than they are different. The researchers of the study did note that because of the cost of the brain scans, they could only put so many women through the scanners, which is why it was such a small group that participated in this part of the study. The researchers are hoping that others will begin to do a similar study with the fMRI, so that more women will be able to be studied, and this could help validate the results of the brain scan.