Featured Research

from universities, journals, and other organizations

Dyslexia caused by faulty signal processing in brain; Finding offers clues to potential treatments

Date:
August 7, 2012
Source:
Max-Planck-Gesellschaft
Summary:
Researchers have made a major step forward in understanding the cause of dyslexia. The scientists have discovered an important neural mechanism underlying dyslexia and shown that many difficulties associated with dyslexia can potentially be traced back to a malfunction of the medial geniculate body in the thalamus. The results provide an important basis for developing potential treatments.

This figure compares the situation in the brain of dyslexics and the control group. The blue area depicts the auditory cortices and the green area represents the medial geniculate bodies.
Credit: © MPI for Human Cognitive and Brain Sciences

Many children and adults have difficulties reading and writing, and the reason is not always obvious. Those who suffer from dyslexia can exhibit a variety of symptoms. Thanks to research carried out by Begoña Díaz and her colleagues at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, a major step forward has been made in understanding the cause of dyslexia.

Related Articles


The scientists have discovered an important neural mechanism underlying dyslexia and shown that many difficulties associated with dyslexia can potentially be traced back to a malfunction of the medial geniculate body in the thalamus. The results provide an important basis for developing potential treatments.

People who suffer from dyslexia have difficulties with identifying speech sounds in spoken language. For example, while most children are able to recognise whether two words rhyme even before they go to school, dyslexic children often cannot do this until late primary school age. Those affected suffer from dyslexia their whole lives. However, there are also always cases where people can compensate for their dyslexia. "This suggests that dyslexia can be treated. We are therefore trying to find the neural causes of this learning disability in order to create a basis for improved treatment options," says Díaz.

Between five and ten percent of the world's children suffer from dyslexia, yet very little is known about its causes. Even though those affected do not lack intelligence or schooling, they have difficulties in reading, understanding and explaining individual words or entire texts. The researchers showed that dyslexic adults have a malfunction in a structure that transfers auditory information from the ear to the cortex is a major cause of the impairment: the medial geniculate body in the auditory thalamus does not process speech sounds correctly. "This malfunction at a low level of language processing could percolate through the entire system. This explains why the symptoms of dyslexia are so varied," says Díaz.

Under the direction of Katharina von Kriegstein, the researchers conducted two experiments in which several volunteers had to perform various speech comprehension tasks. When affected individuals performed tasks that required the recognition of speech sounds, as compared to recognize the voices that pronounced the same speech, magnetic resonance tomography (MRT) recordings showed abnormal responses in the area around the medial geniculate body. In contrast, no differences were apparent between controls and dyslexic participants if the tasks involved only listening to the speech sounds without having to perform a specific task. "The problem, therefore, has nothing to do with sensory processing itself, but with the processing involved in speech recognition," says Díaz. No differences could be ascertained between the two test groups in other areas of the auditory signalling path.

The findings of the Leipzig scientists combine various theoretical approaches, which deal with the cause of dyslexia and, for the first time, bring together several of these theories to form an overall picture. "Recognising the cause of a problem is always the first step on the way to a successful treatment," says Díaz. The researchers' next project is now to study whether current treatment programmes can influence the medial geniculate body in order to make learning to read easier for everyone in the long term.


Story Source:

The above story is based on materials provided by Max-Planck-Gesellschaft. Note: Materials may be edited for content and length.


Journal Reference:

  1. B. Diaz, F. Hintz, S. J. Kiebel, K. von Kriegstein. Dysfunction of the auditory thalamus in developmental dyslexia. Proceedings of the National Academy of Sciences, 2012; DOI: 10.1073/pnas.1119828109

Cite This Page:

Max-Planck-Gesellschaft. "Dyslexia caused by faulty signal processing in brain; Finding offers clues to potential treatments." ScienceDaily. ScienceDaily, 7 August 2012. <www.sciencedaily.com/releases/2012/08/120807104938.htm>.
Max-Planck-Gesellschaft. (2012, August 7). Dyslexia caused by faulty signal processing in brain; Finding offers clues to potential treatments. ScienceDaily. Retrieved November 25, 2014 from www.sciencedaily.com/releases/2012/08/120807104938.htm
Max-Planck-Gesellschaft. "Dyslexia caused by faulty signal processing in brain; Finding offers clues to potential treatments." ScienceDaily. www.sciencedaily.com/releases/2012/08/120807104938.htm (accessed November 25, 2014).

Share This


More From ScienceDaily



More Mind & Brain News

Tuesday, November 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Are Female Bosses More Likely To Be Depressed?

Are Female Bosses More Likely To Be Depressed?

Newsy (Nov. 24, 2014) — A new study links greater authority with increased depressive symptoms among women in the workplace. Video provided by Newsy
Powered by NewsLook.com
Winter Can Cause Depression — Here's How To Combat It

Winter Can Cause Depression — Here's How To Combat It

Newsy (Nov. 23, 2014) — Millions of American suffer from seasonal depression every year. It can lead to adverse health effects, but there are ways to ease symptoms. Video provided by Newsy
Powered by NewsLook.com
Could Your Genes Be The Reason You're Single?

Could Your Genes Be The Reason You're Single?

Newsy (Nov. 21, 2014) — Researchers in Beijing discovered a gene called 5-HTA1, and carriers are reportedly 20 percent more likely to be single. Video provided by Newsy
Powered by NewsLook.com
Milestone Birthdays Can Bring Existential Crisis, Study Says

Milestone Birthdays Can Bring Existential Crisis, Study Says

Newsy (Nov. 21, 2014) — Researchers find that as people approach new decades in their lives they make bigger life decisions. 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