The Connected Hemispheres—The Role of the Corpus Callosum for Hemispheric Asymmetries

AbstractThe present study is interested in the role of the corpus callosum in the development of the language network. We, therefore, investigated language abilities and the language network using task-based fMRI in three cases of complete agenesis of the corpus callosum (ACC), three cases of partial ACC and six controls. Although the children with complete ACC revealed impaired functions in specific language domains, no child with partial ACC showed a test score below average. As a group, ACC children performed significantly worse than healthy controls in verbal fluency and naming. Furthermore, whole-brain ROI-to-ROI connectivity analyses revealed reduced intrahemispheric and right intrahemispheric functional connectivity in ACC patients as compared to controls. In addition, stronger functional connectivity between left and right temporal areas was associated with better language abilities in the ACC group. In healthy controls, no association between language abilities and connectivity was found. Our results show that ACC is associated not only with less interhemispheric, but also with less right intrahemispheric language network connectivity in line with reduced verbal abilities. The present study, thus, supports the excitatory role of the corpus callosum in functional language network connectivity and language abilities.

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Role of the Corpus Callosum in Speech Comprehension: Interfacing Syntax and Prosody

Neuron ◽

10.1016/j.neuron.2006.11.020 ◽

2007 ◽

Vol 53 (1) ◽

pp. 135-145 ◽

Cited By ~ 56

Author(s):

Angela D. Friederici ◽

D. Yves von Cramon ◽

Sonja A. Kotz

Keyword(s):

Corpus Callosum ◽

Speech Comprehension

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The role of the corpus callosum in the development of interocular eye alignment and the organization of the visual field in the cat

Experimental Brain Research ◽

10.1007/bf00238468 ◽

1979 ◽

Vol 36 (1) ◽

Cited By ~ 29

Author(s):

A.J. Elberger

Keyword(s):

Visual Field ◽

Corpus Callosum ◽

Eye Alignment

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On Synchronizing Coupled Retinogeniculocortical Pathways: A Toy Model

Computational Intelligence and Neuroscience ◽

10.1155/2018/6858176 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6

Author(s):

B. L. Mayer ◽

L. H. A. Monteiro

Keyword(s):

Neural Network ◽

Visual Cortex ◽

Corpus Callosum ◽

Neuronal Activity ◽

Network Topology ◽

Cerebral Hemisphere ◽

State Transition ◽

Regular Lattice ◽

Visual Cortices

A Newman-Watts graph is formed by including random links in a regular lattice. Here, the emergence of synchronization in coupled Newman-Watts graphs is studied. The whole neural network is considered as a toy model of mammalian visual pathways. It is composed by four coupled graphs, in which a coupled pair represents the lateral geniculate nucleus and the visual cortex of a cerebral hemisphere. The hemispheres communicate with each other through a coupling between the graphs representing the visual cortices. This coupling makes the role of the corpus callosum. The state transition of neurons, supposed to be the nodes of the graphs, occurs in discrete time and it follows a set of deterministic rules. From periodic stimuli coming from the retina, the neuronal activity of the whole network is numerically computed. The goal is to find out how the values of the parameters related to the network topology affect the synchronization among the four graphs.

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A higher proportion of ermin-immunopositive oligodendrocytes in areas of remyelination

PLoS ONE ◽

10.1371/journal.pone.0256155 ◽

2021 ◽

Vol 16 (8) ◽

pp. e0256155

Author(s):

Intakhar Ahmad ◽

Stig Wergeland ◽

Eystein Oveland ◽

Lars Bø

Keyword(s):

Multiple Sclerosis ◽

White Matter ◽

Corpus Callosum ◽

Mouse Model ◽

Grey Matter ◽

Early Stage ◽

Relative Proportion ◽

Normal Appearing White Matter ◽

The Brain

Incomplete remyelination is frequent in multiple sclerosis (MS)-lesions, but there is no established marker for recent remyelination. We investigated the role of the oligodendrocyte/myelin protein ermin in de- and remyelination in the cuprizone (CPZ) mouse model, and in MS. The density of ermin+ oligodendrocytes in the brain was significantly decreased after one week of CPZ exposure (p < 0.02). The relative proportion of ermin+ cells compared to cells positive for the late-stage oligodendrocyte marker Nogo-A increased at the onset of remyelination in the corpus callosum (p < 0.02). The density of ermin-positive cells increased in the corpus callosum during the CPZ-phase of extensive remyelination (p < 0.0001). In MS, the density of ermin+ cells was higher in remyelinated lesion areas compared to non-remyelinated areas both in white- (p < 0.0001) and grey matter (p < 0.0001) and compared to normal-appearing white matter (p < 0.001). Ermin immunopositive cells in MS-lesions were not immunopositive for the early-stage oligodendrocyte markers O4 and O1, but a subpopulation was immunopositive for Nogo-A. The data suggest a relatively higher proportion of ermin immunopositivity in oligodendrocytes compared to Nogo-A indicates recent or ongoing remyelination.

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Chudley–McCullough Syndrome: Case Report and the Role of Neuroimaging to Suggest the Diagnosis

Journal of Pediatric Neurology ◽

10.1055/s-0041-1731411 ◽

2021 ◽

Author(s):

Leonardo Furtado Freitas ◽

Gabriel Santaterra Barros ◽

Enrico Affonso Barletta ◽

Pablo Picasso de Araújo Coimbra ◽

Charles Marques Lourenço ◽

...

Keyword(s):

Corpus Callosum ◽

Autosomal Recessive ◽

Developmental Delays ◽

Early Recognition ◽

Clinical Syndrome ◽

Diagnostic Odyssey ◽

Cerebellar Dysplasia ◽

Autosomal Recessive Condition

AbstractChudley–McCullough syndrome (CMS) is an autosomal recessive condition first described in 1997. The most striking features of this syndrome include sensorineural hearing loss, craniofacial disproportion, and brain abnormalities such as agenesis of the corpus callosum, polymicrogyria, ventriculomegaly, and changes in cerebellar architecture. We describe the case of a 2-year-old patient with CMS confirmed by genetic testing (GPSM2 gene mutation), who presented with global developmental delays and characteristic neuroimaging features including arachnoid cysts, agenesis of the corpus callosum, cerebellar dysplasia, and frontal heterotopia. Early recognition of this rare clinical syndrome may reduce the diagnostic odyssey and ultimately improve the quality of life for affected children. This report will focus on unique clinical and radiographic features of CMS.

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