Featured Research

from universities, journals, and other organizations

Brain Scans Link Two Key Pieces Of Schizophrenia Puzzle

Date:
January 28, 2002
Source:
NIH/National Institute Of Mental Health
Summary:
Using functional brain imaging, National Institute of Mental Health scientists for the first time have linked two key, but until now unconnected, brain abnormalities in schizophrenia. They have shown that the less patients' frontal lobes activate during a working memory task, the more the chemical messenger dopamine, thought to underlie the delusions and hallucinations of schizophrenia, rises abnormally in the striatum, a relay station deep in the brain.

Using functional brain imaging, National Institute of Mental Health scientists for the first time have linked two key, but until now unconnected, brain abnormalities in schizophrenia. They have shown that the less patients' frontal lobes activate during a working memory task, the more the chemical messenger dopamine, thought to underlie the delusions and hallucinations of schizophrenia, rises abnormally in the striatum, a relay station deep in the brain. Together with other evidence, this suggests that the excess dopamine activity that antipsychotic drugs quell may be driven by a defect in the prefrontal cortex, the brain's executive control center. Andreas Meyer-Lindenberg, M.D., and Karen Berman, M.D., report on their PET (positron emission tomography) study, published online January 28, 2002, in Nature Neuroscience.

Related Articles


The most disabling form of mental illness, schizophrenia affects one percent of the adult population, typically in young adulthood, with hallucinations, delusions, social withdrawal, flattened emotions and loss of social and personal care skills. Although the cause of the disorder remains a mystery, studies that shed light on the role of dopamine in schizophrenia hold promise for advancing understanding and, ultimately, improving treatments.

The researchers used two different types of radioactive tracers in the same scanning sessions with 6 patients and 6 healthy controls to simultaneously monitor two different types of brain activity. A radioactive form of oxygen revealed where blood flowed, and hence what parts of the brain were active, during the experimental task. A radioactively-tagged chemical precursor of dopamine indicated activity of this chemical messenger. The PET scanner employs an array of radiation detectors to get a fix on the destinations of the tracers, producing color-coded, quantitative images of the activity being measured.

The scans were taken while patients performed an abstract reasoning / working memory task that activates the prefrontal cortex. As in previous studies, the patients showed reduced prefrontal activation and performed poorly on the task, suggesting disturbed functioning of that part of the brain. Also consistent with previous findings, patients' striatal dopamine activity was abnormally elevated. In patients, but not in controls, the researchers observed a tight coupling and highly significant inverse correlation between these two abnormalities, suggesting that they share a "common pathophysiological mechanism."

The striking linkage is likely traceable to a primary dysfunction of the prefrontal cortex, argue the investigators, who cite basic science findings that dopamine activity in the striatum is under the control of the prefrontal area. Stimulating or inhibiting this area affects firing of striatal neurons and dopamine release. A recent study in rats found that neurons that project from the prefrontal cortex to the striatum are inhibitory in effect, suggesting an anatomical mechanism by which reduced prefrontal activity might take the brakes off striatal dopamine release. Using magnetic resonance spectroscopy, colleagues in the NIMH Clinical Brain Disorders Branch have discovered a similar correlation between decreased NAA (N-Acetyl Aspartate), an indicator of the health of cells, in the prefrontal cortex, and excess dopamine release in response to amphetamine.

"These results provide a long-sought insight into the roots of dopamine dysregulation in schizophrenia," said Berman, "They suggest a possible treatment strategy that targets prefrontal cortex dysfunction, not just excess dopamine."

Also participating in the research were: Daniel Weinberger, M.D., Philip Kohn, Giuseppe Esposito, M.D., NIMH; Robert Miletich, M.D., Ph.D., Mario Quarantelli, M.D., National Institute on Neurological Disorders and Stroke; Richard Carson, Ph.D., NIH Clinical Center.

The National Institute of Mental Health (NIMH) is part of the National Institutes of Health (NIH), the Federal Government's primary agency for biomedical and behavioral research. NIH is a component of the U.S. Department of Health and Human Services.


Story Source:

The above story is based on materials provided by NIH/National Institute Of Mental Health. Note: Materials may be edited for content and length.


Cite This Page:

NIH/National Institute Of Mental Health. "Brain Scans Link Two Key Pieces Of Schizophrenia Puzzle." ScienceDaily. ScienceDaily, 28 January 2002. <www.sciencedaily.com/releases/2002/01/020128080007.htm>.
NIH/National Institute Of Mental Health. (2002, January 28). Brain Scans Link Two Key Pieces Of Schizophrenia Puzzle. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2002/01/020128080007.htm
NIH/National Institute Of Mental Health. "Brain Scans Link Two Key Pieces Of Schizophrenia Puzzle." ScienceDaily. www.sciencedaily.com/releases/2002/01/020128080007.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Touch-Free Smart Phone Empowers Mobility-Impaired

Touch-Free Smart Phone Empowers Mobility-Impaired

Reuters - Innovations Video Online (Dec. 21, 2014) A touch-free phone developed in Israel enables the mobility-impaired to operate smart phones with just a movement of the head. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Earthworms Provide Cancer-Fighting Bacteria

Earthworms Provide Cancer-Fighting Bacteria

Reuters - Innovations Video Online (Dec. 21, 2014) Polish scientists isolate bacteria from earthworm intestines which they say may be used in antibiotics and cancer treatments. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Reuters - Innovations Video Online (Dec. 21, 2014) A team of scientists led by Danish chemist Jorn Christensen says they have isolated two chemical compounds within an existing antipsychotic medication that could be used to help a range of failing antibiotics work against killer bacterial infections, such as Tuberculosis. Jim Drury went to meet him. Video provided by Reuters
Powered by NewsLook.com
Hugging It Out Could Help You Ward Off A Cold

Hugging It Out Could Help You Ward Off A Cold

Newsy (Dec. 21, 2014) Carnegie Mellon researchers found frequent hugs can help people avoid stress-related illnesses. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins