Diffusion weighted imaging evidence of extra-callosal pathways for interhemispheric communication after complete commissurotomy

Document Type

Article

Publication Date

6-1-2019

Abstract

The integrity of white matter architecture in the human brain is related to cognitive processing abilities. The corpus callosum is the largest white matter bundle interconnecting the two cerebral hemispheres. “Split-brain” patients in whom all cortical commissures have been severed to alleviate intractable epilepsy demonstrate remarkably intact cognitive abilities despite the lack of this important interhemispheric pathway. While it has often been speculated that there are compensatory alterations in the remaining interhemispheric fibers in split-brain patients several years post-commissurotomy, this has never been directly shown. Here we examined extra-callosal pathways for interhemispheric communication in the brain of a patient who underwent complete cerebral commissurotomy using diffusion weighted imaging tractography. We found that compared with a healthy age-matched comparison group, the split-brain patient exhibited increased fractional anisotropy (FA) of the dorsal and ventral pontine decussations of the cortico-cerebellar interhemispheric pathways. Few differences were observed between the patient and the comparison group with respect to FA of other long-range intrahemispheric fibers. These results point to specific cerebellar anatomical substrates that may account for the spared interhemispheric coordination and intact cognitive abilities that have been extensively documented in this unique patient.

Identifier

85065431913 (Scopus)

Publication Title

Brain Structure and Function

External Full Text Location

https://doi.org/10.1007/s00429-019-01864-2

e-ISSN

18632661

ISSN

18632653

PubMed ID

31062161

First Page

1897

Last Page

1909

Issue

5

Volume

224

Grant

R01MH094639

Fund Ref

National Institute of Mental Health

This document is currently not available here.

Share

COinS