Navigation Links
Brain structural deficits may contribute to increased functional connections

Philadelphia, PA -- Major depressive disorder is associated with a dysregulation of brain regions including the prefrontal cortex and limbic system. The relationship between structural and functional abnormalities in these brain regions in depressed patients is far from clear. However, both types of changes are assumed to underlie the symptoms of this disorder.

This lack of understanding prompted Dr. Bart de Kwaasteniet at the Academic Medical Center in Amsterdam and his colleagues to use a multimodal neuroimaging approach to further investigate this relationship.

The researchers, led by Professor Damiaan Denys, recruited 18 patients with major depressive disorder and 24 healthy individuals, all of whom underwent multiple neuroimaging scans. They specifically focused on the structural and functional connectivity between the subgenual anterior cingulate cortex (ACC) and the medial temporal lobe, two regions that are connected by a white matter tract called the uncinate fasciculus. These regions are known to be involved in the regulation of emotion and memory.

de Kwaasteniet explained their findings: "We identified decreased structural integrity of the uncinate fasciculus connecting the medial temporal lobe and the subgenual ACC. Furthermore, we identified an increased functional connection between these regions in major depression relative to controls. Importantly, we identified a negative correlation between the integrity of this white matter tract and the functional connection between the subgenual ACC and bilateral hippocampus in major depression."

These results suggest that structural disturbances in the uncinate fasciculus contribute to abnormally high functional interactions among brain circuits associated with the symptoms of depression. "This leads to the hypothesis that abnormalities in brain structure lead to differences in connectivity between brain areas in depressive disorder," added de Kwaasteniet.

However, they also hypothesized that the reverse may be true as well. In other words, that the increased functional connectivity among these brain regions leads to structural changes in the brain's white matter fibers by means of an abnormally increased signal transduction. This hypothesis is supported by recent studies in schizophrenia which suggest that circuit hyperactivity may be a predictor of subsequent cortical atrophy.

"This interesting study suggests that abnormalities in the structural connections between brain regions, the white matter, are associated with abnormal activity within a brain circuit implicated in the symptoms of depression. This observation raises an important question about the implications of treating the circuit functional abnormalities without fixing the underlying brain structure," commented Dr. John Krystal, Editor of Biological Psychiatry. "Perhaps the structural abnormalities contribute to the risk for the relapse of depression among individuals whose brain circuit activity has responded to antidepressant medications."

More research will be necessary to test the theories generated from the findings of this study.


Contact: Rhiannon Bugno

Related medicine news :

1. Study Suggests Vaccine May Help Kids With Brain Cancer
2. Epilepsy Leads to More Brain Abnormalities Over Time
3. UCLA Brain Injury Research Center gets NCAA funding for research on sports concussions
4. Why is traumatic brain injury increasing among the elderly?
5. Brain Falters Near End of Life, but Games, Puzzles Might Slow Decline
6. Dental X-Rays May Be Linked to Benign Brain Tumors
7. Nonsurgical Method to Measure Brain Pressure Shows Promise
8. Researchers Map Brain Regions Linked to Intelligence
9. Football-related catastrophic brain injuries on the rise
10. Brain Tumor Vaccine Shows Promise in Early Trial
11. Brain Surgery Might Ease Tough-to-Treat OCD
Post Your Comments:
(Date:11/27/2015)... LOS ANGELES, CA (PRWEB) , ... November 27, 2015 , ... MPWH, the No.1 Herpes-only ... age of 30 (see Table 1-1 ). More than 3.7 billion people under ... simplex virus type 1 (HSV-1), according to WHO's first global estimates of HSV-1 infection ...
(Date:11/27/2015)... , ... November 27, 2015 , ... ... Secura Consultants has prided itself for not only fulfilling the needs of advisers ... solutions at an affordable price and providing top-tier customer service. However, there's always ...
(Date:11/27/2015)... ... November 27, 2015 , ... Dr. Thomas Dunlap and ... Dr. Tucker Bierbaum with Emergency Medicine at St., Joseph Health System’s Santa Rosa ... Sepsis conditions present in similar ways and require time-critical intervention to avoid large area ...
(Date:11/26/2015)... ... 26, 2015 , ... Inevitably when people think Thanksgiving, they also think Holiday ... the Black Friday and Cyber Monday massage chair sales to receive the ... and low to find the best massage chair deals, they can see all of ...
(Date:11/26/2015)... ... ... Jobs in hospital medical laboratories and in the imaging field lead the many ... Medical Group . These fields, as well as travel nursing, ranked at ... through the company’s website, , The leading healthcare staffing agency released ...
Breaking Medicine News(10 mins):
(Date:11/25/2015)... Nov. 25, 2015  Amgen (NASDAQ: AMGN ) ... (BLA) with the United States ... a biosimilar candidate to Humira ® (adalimumab). Amgen ... submitted to the FDA and represents Amgen,s first BLA ... E. Harper , M.D., executive vice president of Research ...
(Date:11/25/2015)... N.Y. , Nov. 25, 2015  Linden Care, ... and optimizing treatment outcomes for patients suffering from chronic ... request for a Temporary Restraining Order (TRO) enjoining Express ... the two companies. --> ... pursuing all of its legal options. ...
(Date:11/25/2015)... On Tuesday, November 24, 2015, the ... Wright Medical Technology, Inc. for product liability and ... implant device, awarded $11 million in favor of ... and three days of deliberations, the jury found ... designed and unreasonably dangerous, and that Wright Medical ...
Breaking Medicine Technology: