Featured Research

from universities, journals, and other organizations

How clear is our view of brain activity?

Date:
March 16, 2011
Source:
Albert-Ludwigs-Universität Freiburg
Summary:
Imaging techniques have become an integral part of the neurosciences. Methods that enable us to look through the human skull and right into the active brain have become an important tool for research and medical diagnosis alike. However, the underlying data have to be processed in elaborate ways before a colorful image informs us about brain activity.

Interfering filters: In the identical original data set, a region of the brain (circled) appears active in one case, but not in the other – solely dependent on the “mesh size” of the used data filter.
Credit: Image courtesy of Albert-Ludwigs-Universität Freiburg

Imaging techniques have become an integral part of the neurosciences. Methods that enable us to look through the human skull and right into the active brain have become an important tool for research and medical diagnosis alike. However, the underlying data have to be processed in elaborate ways before a colourful image informs us about brain activity.

Related Articles


Scientists from Freiburg and colleagues were now able to demonstrate how the use of different filters may influence the resulting images and lead to contradicting conclusions.

In the current issue of Human Brain Mapping, Tonio Ball of the Bernstein Center Freiburg and colleagues from the universities of Oldenburg, Basel and Magdeburg demonstrate how variable the results of imaging techniques like functional Magnetic Resonance Imaging (fMRI) can be -- depending on the way how the original data are filtered. The use of filtering algorithms is indispensable in order to separate meaningful information from inherent noise that is part of every data set. These filters have different "mesh sizes" or widths, and are indispensable in the first place to reveal activity patterns that span different scale sizes. In most cases, only a filter of one specific width, which differs from study to study, is employed.

Tonio Ball and colleagues systematically investigated the influence of the mesh size of these filters on the resulting imagery of brain activity. They conducted an experiment during which test persons had to rate music by pressing a button while lying in an fMRI scanner. During this task, brain regions responsible for hearing, vision, and arm movements were active. The scientists treated the gained data with filters of different widths and found surprising results: The filters had a marked influence on the outcome of the brain scan analyses, showing increased brain activity in one region in one case, and in a different region -- in the other. Even smallest changes in filter width led to areas of the brain appearing to be either active or inactive. This effect can ultimately lead to widely disparate interpretations of such a scan.

Tonio Ball and his colleagues therefore stress the importance of taking into account the effect of filtering in future interpretations of fMRI studies. This way, scientists won't run the risk of inadvertently skewing our view of the brain.


Story Source:

The above story is based on materials provided by Albert-Ludwigs-Universität Freiburg. Note: Materials may be edited for content and length.


Journal Reference:

  1. Tonio Ball, Thomas P.K. Breckel, Isabella Mutschler, Ad Aertsen, Andreas Schulze-Bonhage, Jürgen Hennig, Oliver Speck. Variability of fMRI-response patterns at different spatial observation scales. Human Brain Mapping, 2011; DOI: 10.1002/hbm.21274

Cite This Page:

Albert-Ludwigs-Universität Freiburg. "How clear is our view of brain activity?." ScienceDaily. ScienceDaily, 16 March 2011. <www.sciencedaily.com/releases/2011/03/110316134605.htm>.
Albert-Ludwigs-Universität Freiburg. (2011, March 16). How clear is our view of brain activity?. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2011/03/110316134605.htm
Albert-Ludwigs-Universität Freiburg. "How clear is our view of brain activity?." ScienceDaily. www.sciencedaily.com/releases/2011/03/110316134605.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Best Tips to Curb Holiday Carbs

The Best Tips to Curb Holiday Carbs

Buzz60 (Dec. 19, 2014) — It's hard to resist those delicious but fattening carbs we all crave during the winter months, but there are some ways to stay satisfied without consuming the extra calories. Vanessa Freeman (@VanessaFreeTV) has the details. Video provided by Buzz60
Powered by NewsLook.com
Sierra Leone Bikers Spread the Message to Fight Ebola

Sierra Leone Bikers Spread the Message to Fight Ebola

AFP (Dec. 19, 2014) — More than 100 motorcyclists hit the road to spread awareness messages about Ebola. Nearly 7,000 people have now died from the virus, almost all of them in west Africa, according to the World Health Organization. Video provided by AFP
Powered by NewsLook.com
Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) — In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) — A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
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