Featured Research

from universities, journals, and other organizations

Dyslexia Varies Across Languages

Date:
October 13, 2009
Source:
Cell Press
Summary:
Chinese-speaking children with dyslexia have a disorder that is distinctly different, and perhaps more complicated and severe, than that of English speakers. Those differences can be seen in the brain and in the performance of Chinese children on visual and oral language tasks, reveals a new report.

Chinese-speaking children with dyslexia have a disorder that is distinctly different, and perhaps more complicated and severe, than that of English speakers. Those differences can be seen in the brain and in the performance of Chinese children on visual and oral language tasks, reveals a report published online on October 12th in Current Biology.

English dyslexia consists of a "phonological disorder," meaning that people with the condition have trouble detecting or manipulating the sound structure of oral language, which in turn leads to problems in mapping speech sounds onto letters, explained Wai Ting Siok of the University of Hong Kong. In contrast, the new findings show that developmental dyslexia in Chinese is really two disorders: a visuospatial deficit and a phonological disorder combined.

Siok and her colleague Li Hai Tan say the difference can be traced to the characteristics of the two languages. "In English, the alphabetic letters that form visual words are pronounceable, so access to the pronunciation of English words is made possible by using letter-to-sound conversion rules," Siok said. "Written Chinese maps graphic forms—i.e., characters—onto meanings; Chinese characters possess a number of intricate strokes packed into a square configuration, and their pronunciations must be memorized by rote. This characteristic suggests that a fine-grained visuospatial analysis must be performed by the visual system in order to activate the characters' phonological and semantic information. Consequently, disordered phonological processing may commonly coexist with abnormal visuospatial processing in Chinese dyslexia."

The researchers asked normal and dyslexic Chinese readers to judge the physical size of visual stimuli and found that normal readers performed significantly better than dyslexic readers. Brain scans showed that, compared with normal readers, dyslexics exhibited weaker activation in a portion of the brain known to mediate visuospatial processing. Crucially, Siok said, most Chinese dyslexics with the visuospatial problem also exhibited a phonological processing disorder, as demonstrated by their poor performance in a phonology-related rhyme judgment task, suggesting the coexistence of two disorders.

"Our study for the first time demonstrates the coexistence of visuospatial and phonological disorders in dyslexics," which presents a challenge to current theories to explain developmental dyslexia, Tan said. "Our results strongly indicate the need for a unifying theory of sufficient scope to accommodate the full complexity of the observed dysfunctions and interactions of the brain systems underlying reading impairments."

The researchers include Wai Ting Siok, The University of Hong Kong, Hong Kong, China; John A. Spinks, The University of Hong Kong, Hong Kong, China; Zhen Jin, Beijing Hospital, Beijing, China; and Li Hai Tan, The University of Hong Kong, Hong Kong, China.


Story Source:

The above story is based on materials provided by Cell Press. Note: Materials may be edited for content and length.


Cite This Page:

Cell Press. "Dyslexia Varies Across Languages." ScienceDaily. ScienceDaily, 13 October 2009. <www.sciencedaily.com/releases/2009/10/091012121333.htm>.
Cell Press. (2009, October 13). Dyslexia Varies Across Languages. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2009/10/091012121333.htm
Cell Press. "Dyslexia Varies Across Languages." ScienceDaily. www.sciencedaily.com/releases/2009/10/091012121333.htm (accessed July 24, 2014).

Share This




More Mind & Brain News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Idaho Boy Helps Brother With Disabilities Complete Triathlon

Idaho Boy Helps Brother With Disabilities Complete Triathlon

Newsy (July 23, 2014) An 8-year-old boy helped his younger brother, who has a rare genetic condition that's confined him to a wheelchair, finish a triathlon. Video provided by Newsy
Powered by NewsLook.com
Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Newsy (July 22, 2014) The 83 new genetic markers could open dozens of new avenues for schizophrenia treatment research. Video provided by Newsy
Powered by NewsLook.com
Why Do People Believe We Only Use 10 Percent Of Our Brains?

Why Do People Believe We Only Use 10 Percent Of Our Brains?

Newsy (July 22, 2014) The new sci-fi thriller "Lucy" is making people question whether we really use all our brainpower. But, as scientists have insisted for years, we do. Video provided by Newsy
Powered by NewsLook.com
Do Obese Women Have 'Food Learning Impairment'?

Do Obese Women Have 'Food Learning Impairment'?

Newsy (July 18, 2014) Yale researchers tested 135 men and women, and it was only obese women who were deemed to have "impaired associative learning." 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:
from the past week

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