Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Brain images reveal effects of antidepressants

06.02.2003


The experiences of millions of people have proved that antidepressants work, but only with the advent of sophisticated imaging technology have scientists begun to learn exactly how the medications affect brain structures and circuits to bring relief from depression.



Researchers at the University of Wisconsin-Madison and UW Medical School recently added important new information to the growing body of knowledge. For the first time, they used functional magnetic resonance imaging (fMRI)--technology that provides a view of the brain as it is working--to see what changes occur over time during antidepressant treatment while patients experience negative and positive emotions.

The study appears in the January issue of the American Journal of Psychiatry. UW psychology professor Richard Davidson, Ph.D., psychiatry department chair Ned Kalin, MD, research associate William Irwin and research assistant Michael Anderle were the authors.


The researchers found that when they gave the antidepressant venlafaxine (Effexor(r)) to a small group of clinically depressed patients, the drug produced robust alterations in the anterior cingulate. This area of the brain has to do with focused attention and also becomes activated when people face conflicts. Unexpectedly, the changes were observed in just two weeks.

"Conducting repeated brain scans in these patients allowed us to see for the first time how quickly antidepressants work on brain mechanisms," said Davidson, who also is director of the W. M. Keck Laboratory for Functional Brain Imaging and Behavior, where imaging for the study took place. He noted that the findings were surprising because patients don’t usually begin noticing mood improvements until after they have been taking antidepressants for three to five weeks.

The researchers also found that while the depressed patients displayed lower overall activity in the anterior cingulate than non-depressed controls, those depressed patients who showed relatively more activity before treatment responded better to the medication than those with lower pre-treatment activity. This kind of information may be extremely useful to clinicians someday, Kalin said.

"We expect that physicians in the future will be able to predict which patients will be the best candidates for antidepressants simply by looking at brain scans that reveal this type of pertinent information," said Kalin, who also is director of the HealthEmotions Research Institute, where scientists concentrate on uncovering the scientific basis of linkages between emotions and health. One third of all patients treated with antidepressants do not respond to them, and of those that do, only about 50 percent get completely better, he added.

Virtually all previous studies analyzing brain activity in depressed people used PET (positron emission tomography) and SPECT (single photon emission computed tomography) technology. With these imaging systems scientists were not able to obtain pictures with the same resolution as that which is now obtainable with fMRI, which provides a "working snapshot" of the brain.

The Wisconsin team used fMRI’s capability to capture brain activity as it occurred to record subjects’ reactions as they viewed pictures designed to stimulate negative and positive emotions.

"We believe that we can uncover the best indicators of treatment changes when we present research subjects these emotion challenges," said Davidson. "The pictures activate the individual circuits that underlie different kinds of emotional responses."

UW emotions researchers have been using fMRIs with emotion-challenging pictures for several years in an effort to understand normal and abnormal brain responses to a range of emotions. They theorize that in depressed people, reactions to negative emotions are similar to, but more exaggerated than, reactions that non-depressed people have, and that the reactions may be more difficult to turn off.

"We all experience some sadness from time to time, but in depression, the responses may be sustained and out of context," said psychiatrist Kalin.

With the HealthEmotions Research Institute, the Keck Laboratory for Functional Brain Imaging and Behavior and the Laboratory for Affective Neuroscience, UW is home to a critical mass of some of the foremost emotions researchers in the world.


###
CONTACT: Dian Land, 608-263-9893, dj.land@hosp.wisc.edu; Lisa Brunette, 608-263-5830, la.brunette@hosp.wisc.edu.

Dian Land | EurekAlert!
Further information:
http://www.wisc.edu/

More articles from Health and Medicine:

nachricht TSRI researchers develop new method to 'fingerprint' HIV
29.03.2017 | Scripps Research Institute

nachricht Periodic ventilation keeps more pollen out than tilted-open windows
29.03.2017 | Technische Universität München

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>