MAY 05, 2015 04:52 PM PDT

Fuzzy Thinking Linked with Mood Disorders

Women "of a certain age" worry that fuzzy thinking - the inability to remember or focus - may be a symptom of Alzheimer's disease or some other form of dementia. Instead, a study at the University of Michigan in Ann Arbor suggests that it is a symptom of depression and bipolar disorder. The study, reported in the journal Brain, even puts these conditions on a continuum.
The study showed that women with depression or bipolar disorder demonstrated lower levels of activity than their healthy counterparts in the right posterior parietal cortex, indicating fuzzy thinking.
As reported by David McNamee in Medical News Today (May 5, 2015), a large study of brain scans showed that impaired executive function, or fuzzy thinking, indicates the mood disorders. Instead of being totally separate conditions, they "exist as points on a spectrum," McNamee said.

The researchers recruited 618 women, 150 of whom were healthy, 266 of whom had the diagnosis of major depression and 202 of whom had bipolar disorder but were not manic at the time of the study. Only female subjects were used to avoid gender differences in the study.

Participants were tested for their ability to maintain their attention and respond to situations quickly. They had to "respond rapidly when certain letters flashed up on a screen, amid a random sequence of other letters," McNamee said.

While women exhibiting depression performed as well as those exhibiting bipolar disorder, both groups performed worse than those without mental health disorders. With a few discrepancies, people with bipolar disorder or depression had scores in the bottom 5 percent.

The next phase of the study was a functional magnetic resonance imaging (fMRI) scan administered to a small sample of the healthy, depressed and bipolar women. Researchers determined that women with mood disorders demonstrated lower levels of activity than the control group in the right posterior parietal cortex, the part of the brain that controls working memory, reasoning and problem solving.

Kelly Ryan, Ph.D., the lead author of the article and a neuropsychologist at the University of Michigan, said that the study demonstrated "a shared cognitive dysfunction in women with mood disorders, which were pronounced in the cognitive control tests and more nuanced in scans." He added that, ""Traditionally in psychiatry we look at a specific diagnosis, or category, but the neurobiology is not categorical - we're not finding huge differences between what clinicians see as categories of disease. This raises questions about traditional diagnoses."
Now that scientists are looking at psychiatric disorders as a continuum instead of as discrete conditions, the National Institute of Mental Health has created an initiative called Research Domain Criteria (RDoC).

As explained by the paper's senior author, Scott Langenecker, Ph.D., "The RDoC initiative is not meant to replace this clinical diagnostic system. It is designed to extend ways of understanding neurobiology, performance and genetics at natures' seams, rather than at groupings of clinical symptoms based on a patient's current memory of recent symptoms and clinician observations of signs. The RDoC initiative is a recognition that we need to rely more heavily on what these neurobiological results are telling us - mental diseases have more overlap in the basic brain and genetic signatures."

Scientists conducting future tests can save money on fMRI testing by starting with cognitive control tests. The fMRI would be reserved for those who perform poorly.

Source: Medical News Today
About the Author
  • Ilene Schneider is the owner of Schneider the Writer, a firm that provides communications for health care, high technology and service enterprises. Her specialties include public relations, media relations, advertising, journalistic writing, editing, grant writing and corporate creativity consulting services. Prior to starting her own business in 1985, Ilene was editor of the Cleveland edition of TV Guide, associate editor of School Product News (Penton Publishing) and senior public relations representative at Beckman Instruments, Inc. She was profiled in a book, How to Open and Operate a Home-Based Writing Business and listed in Who's Who of American Women, Who's Who in Advertising and Who's Who in Media and Communications. She was the recipient of the Women in Communications, Inc. Clarion Award in advertising. A graduate of the University of Pennsylvania, Ilene and her family have lived in Irvine, California, since 1978.
You May Also Like
NOV 01, 2018
Cannabis Sciences
NOV 01, 2018
Meet Anandamide - The "Bliss" Molecule
Many of us are aware of the relatively new discovery of the endocannabinoid system (ECS). This is the system which is hijacked by the famous phytocannabinoid (i.e. from cannabis) compounds......
NOV 05, 2018
Neuroscience
NOV 05, 2018
How does Brain's GPS work?
Understanding the brain cells involved in decoding and encoding naviagtional information....
NOV 15, 2018
Drug Discovery
NOV 15, 2018
A Subclass of Anti-Aging Compounds Serves as Alzheimer's Drug Candidates
In a publication in Trends in Pharmacological Sciences, a subclass of anti-aging compounds, called geroneuroprotectors (GNPs), have been identified in rese...
NOV 23, 2018
Cannabis Sciences
NOV 23, 2018
Our Endocannabinoid System and Appetite
The Thanksgiving holiday is a perfect time to discuss science. Particularly, the science of appetite. While the old wives' tale of the tryptophan in tu...
NOV 26, 2018
Neuroscience
NOV 26, 2018
Most Rewarding Experiences Take The Top Spot In Memory
brain filters out neutral, inconsequential events, retaining only the memories that are useful to the future decisions....
DEC 03, 2018
Neuroscience
DEC 03, 2018
Genes Involved In Dementia Identified
Genetic factors have also been recognized as a critical contributor for dementia and identifying these genes will eventually allow for gene-specific therapeutics to be developed. Although sci...
Loading Comments...