We're unable to sign you in at this time. Please try again in a few minutes.
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
Article |

Dyslexia and Corpus Callosum Morphology

George W. Hynd, EdD; Josh Hall, EdS; Edward S. Novey, MD; Deborah Eliopulos, RT; Kathryn Black, EdS; Jose J. Gonzalez, MA; Jane E. Edmonds, MA; Cynthia Riccio, PhD; Morris Cohen, EdD
Arch Neurol. 1995;52(1):32-38. doi:10.1001/archneur.1995.00540250036010.
Text Size: A A A
Published online


Objective:  There is evolving evidence that developmental dyslexia is associated with anomalous cerebral morphology in the bilateral frontal and left temporoparietal regions. This study examined the morphology of the corpus callosum, as possible deviations in other important structures are poorly understood in this behaviorally diagnosed syndrome.

Design:  Magnetic resonance imaging scans were obtained from children with developmental dyslexia and from matched control children. Morphometric measurements were examined to determine if regional differences existed in the corpus callosum between these two groups of children.

Setting:  Magnetic resonance imaging studies were completed at Athens (Ga) Magnetic Imaging.

Patients and Other Participants:  Sixteen developmental dyslexic children (mean age, 9.7 years) and a matched sample of children who were diagnosed as being normal were examined by using a reliable comprehensive diagnostic process.

Main Outcome Measures:  Using a midsagittal magnetic resonance imaging scan, corpus callosum morphology was evaluated by segmenting the corpus callosum into five regions of interest.

Results:  Analysis of the corpus callosum revealed that the anterior region of interest (the genu) was significantly smaller in the dyslexic children. Significant correlations existed between reading achievement and the region-of-interest measurements for the genu and splenium. Measured intelligence, chronologic age, and gender were not related to region-of-interest measurements of the corpus callosum. Consistent with previous studies, the dyslexic individuals were characterized by significant psychiatric comorbidity, particularly attentiondeficit disorder with and without hyperactivity. Reported familial left-handedness also distinguished the dyslexic children.

Conclusions:  Subtle neurodevelopmental variation in the morphology of the corpus callosum may be associated with the difficulty that dyslexic children experience in reading and on tasks involving interhemispheric transfer.


Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?





Also Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
Please click the checkbox indicating that you have read the full article in order to submit your answers.
Your answers have been saved for later.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.


Some tools below are only available to our subscribers or users with an online account.

0 Citations

Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?

Related Content

Customize your page view by dragging & repositioning the boxes below.