Navigation Links
The radical restructuring of brain networks in comatose patients
Date:12/4/2012

This press release is available in French.

The researchers are focusing on analysing brain networks of brain-damaged comatose (non-traumatised) patients, a state where the individual is considered to be unconscious.

The authors of the study used an original graph theory-based methodology, where images were constructed using functional MRI data at rest and using robust statistical signal-processing methods. Local and overall effectiveness indices of functional brain networks were obtained for 17 brain-damaged patients and 20 healthy volunteers. Correlations in 417 brain regions were extracted to produce brain connection graphs using the statistically significant correlations.

Inserm unit 836 "Grenoble Institut des neurosciences", CNRS researchers from the "GIPSA lab" and from the Behavioural and Clinical Neuroscience Institute in Cambridge, in collaboration with clinical practitioners from the Strasbourg University Hospital Centre, have been able to highlight restructured brain networks in brain-damaged (non-traumatized) comatose patients.

Through comparisons with the healthy subjects, the results demonstrate that the overall cerebral connectivity is preserved in comatose patients. By analysing the connectivity at a local level, the authors of the study have observed that some brain regions ("hubs"), which are highly connected in healthy volunteers, are less well connected in comatose patients. Conversely, the less densely connected regions in the network in healthy subjects become "hubs" in comatose patients.

Brain imaging obtained from connectivity graphs

The connectivity graph method is used to summarize in a single image data acquired through MRI scanning. It translates the effectiveness of connections in a single region compared to all the others. By grouping the most interconnected regions, modules are revealed (each represented by a different colour). Patients and healthy volunteers both have different models in their spatial location, representing radical alterations to the brain connections.

According to current hypotheses, consciousness disorders in persistently comatose patients could be linked to disconnection phenomena between specific cortical regions, particularly the precuneus. The results of this study also point in this direction. "From an overall perspective, the topology of brain connections resists well to traumatism by reorganising the most interconnected regions in the network. It therefore seems that comas may be linked to changes in the location of "hubs" among the brain networks" suggests Chantal Delon Martin, an Inserm researcher.

An assessment of brain injury and comas

Patients with brain injury may go through various clinically-defined states: vegetative state that is characterized by the preserved sleep-wake cycle (eyes opening spontaneously, autonomous breathing, etc.); minimally conscious state where patients have partially preserved environmental consciousness (eye movement capacity, reaction to stimulation); locked in syndrome where the patient is paralysed but conscious (communication using eyes); brain death when the coma is irreversible flat line EEG, no blood flow).

Coma (from the Greek κῶμα kma meaning "deep sleep") is one of the different states where self awareness and consciousness of the outside world is eradicated further to an accident (cerebral, cardiac, etc.). There are two coma phases: the "acute" coma phase (a few days after the accident) and the "chronic" phase (one month or more). Brain restructuring was observed by researchers during the "acute" phase, when it is not known which coma type the patient will develop.

Assessments of brain injuries in comatose patients are currently conducted through clinical examination, morphological MRI, evoked potentials and by SPECT (Single-photon emission computed tomography) or TEP (Positron emission tomography (PET). "The results of this study could help clinical practitioners in the difficult diagnosis process for comatose patients, since this method makes it possible to characterize each patient individually", conclude the researchers.


'/>"/>
Contact: Inserm press office
presse@inserm.fr
INSERM (Institut national de la sant et de la recherche mdicale)
Source:Eurekalert

Related medicine news :

1. Researchers undertake radical new cancer survivorship study
2. EP Global Communications, Inc. Achieves Shareholder Approval for Restructuring and Signs Definitive Restructuring Agreement
3. Study Suggests Vaccine May Help Kids With Brain Cancer
4. Epilepsy Leads to More Brain Abnormalities Over Time
5. UCLA Brain Injury Research Center gets NCAA funding for research on sports concussions
6. Why is traumatic brain injury increasing among the elderly?
7. Brain Falters Near End of Life, but Games, Puzzles Might Slow Decline
8. Dental X-Rays May Be Linked to Benign Brain Tumors
9. Nonsurgical Method to Measure Brain Pressure Shows Promise
10. Researchers Map Brain Regions Linked to Intelligence
11. Football-related catastrophic brain injuries on the rise
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/27/2016)... ... June 27, 2016 , ... "FCPX editors can now reveal their ... Cut Pro X," said Christina Austin - CEO of Pixel Film Studios. , ... Pro X users can now reveal the media of their split screens with ...
(Date:6/27/2016)... Overland Park, KS (PRWEB) , ... June 27, 2016 , ... ... leader in retailers of Eyeglasses . , Millions of individuals in the United ... life, eyeglasses have become a way to both correct vision and make a fashion ...
(Date:6/26/2016)... North Carolina (PRWEB) , ... June 26, 2016 , ... ... release of a new product that was developed to enhance the health of felines. ... for centuries. , The two main herbs in the PawPaws Cat Kidney Support ...
(Date:6/25/2016)... Austin, TX (PRWEB) , ... June 25, 2016 , ... ... Fellow of the American College of Mohs Surgery and to Dr. Russell Peckham for ... popular and highly effective treatment for skin cancer. The selective fellowship in Mohs Micrographic ...
(Date:6/25/2016)... Long Beach, CA (PRWEB) , ... June 25, 2016 , ... ... from UCLA with Magna Cum Laude and his M.D from the David Geffen School ... San Diego and returned to Los Angeles to complete his fellowship in hematology/oncology at ...
Breaking Medicine News(10 mins):
(Date:6/26/2016)... Story Highlights: ... the health care industry is causing providers to review ... Deloitte offers a suite of solutions for health care ... cost optimization: labor resource analysis, revenue cycle optimization and ... outcomes and better economics ...
(Date:6/24/2016)... June 24, 2016 ... announced the addition of the " Global Markets ... This report focuses ... an updated review, including its applications in various applications. ... market, which includes three main industries: pharmaceutical and biotechnology, ...
(Date:6/24/2016)... -- Research and Markets has announced the addition ... report to their offering. ... The World Market for Companion Diagnostics covers the world ... in the report includes the following: , ... by Region (N. America, EU, ROW), 2015-2020 , World ...
Breaking Medicine Technology: