Corpus callosum morphology does not depend on hand preference or hemispheric dominance we language DOI Creative Commons
René Westerhausen, Emma Karlsson, Leah T. Johnstone

et al.

Brain Research, Journal Year: 2025, Volume and Issue: unknown, P. 149574 - 149574

Published: March 1, 2025

It is traditionally assumed that the corpus callosum has a pivotal role in supporting hemispheric lateralisation, which originated from series of studies suggesting differences callosal morphology relation to handedness. However, recent systematic reviews document are only inconsistently reported, and it been speculated these inconsistencies might arise focussing on handedness alone, without considering other lateralized functional modules. To address this short-coming, present pre-registered study was designed re-examine possible effects while hand preference interaction with dominance for language. predicted those individuals who write ipsilateral their language dominant hemisphere, have an increased need interhemispheric integration reflected detectable alteration morphology. That is, individual writing left (LW) being (LLD) larger or thicker than motor production controlled by same hemisphere. We tested prediction comparing between three common groups result when combing preferred (LW vs. right writers, RW) hemisphere processing. For purpose, (LLD dominance, RLD) determined using verbal-fluency task magnetic resonance (fMRI) previously validated. The included N = 220 participants both sexes, 97 were classified as LW/LLD, 73 RW/LLD, 50 LW/RLD. assessed T1-weighted structural MR images midsagittal surface area (subdivided into subregions genu, truncus, posterior third) well regional thickness (at 100 measuring points). statistical analyses did not reveal any evidence support our predictions sample size provides sufficient test power rule out comparatively small reasonable confidence. Thus, appears substantially affected supposed requirement LW/LLD compared RW/LLD LW/RLD individuals.

Language: Английский

Distinct Structural Connectivity Patterns Associated with Variations in Language Lateralisation DOI Creative Commons
Ieva Andrulyte, Laure Zago, Gaël Jobard

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 5, 2025

Abstract Hemispheric asymmetries in white matter tracts are proposed key determinants of language lateralisation, yet evidence healthy individuals remains inconsistent. This suggests that simple tractography techniques might not be sensitive enough to identify dominance. Significant insights into the functional organization human brain may achieved by considering networks and connectivity, providing more information about discrepancies people with different hemispheric In this study, we examined 285 participants compare their structural connectomes at whole-brain level determine responsible for three lateralisation groups (typical, atypical strongly atypical). Probabilistic generated tractograms, fibres were filtered according anatomical Boolean guidelines. Connectivity matrices nodes corresponding supramodal sentence areas atlas edges weighted fractional anisotropy (FA) using graph theory network-based statistic (NBS) approaches. We demonstrated both (bilateral) (right-lateralised) characterised heightened interhemispheric temporal connectivity. Post-hoc analyses showed exhibited increased temporo-frontal while had enhanced frontal connectivity but lacked connections. These patterns diverge from traditional models dominance, suggesting a reliance on integrated bilateral atypically lateralised individuals. reflects distinct neural mechanisms underlying organisation, departing developmental trajectory typical offering cognitive flexibility clinical applications.

Language: Английский

Citations

0
Hemispheric co-lateralization of language and spatial attention reduces performance in dual-task DOI
Miaomiao Zhu, Qing Cai

Brain and Language, Journal Year: 2025, Volume and Issue: 262, P. 105537 - 105537

Published: Jan. 24, 2025

Language: Английский

Citations

0
Corpus callosum morphology does not depend on hand preference or hemispheric dominance we language DOI Creative Commons
René Westerhausen, Emma Karlsson, Leah T. Johnstone

et al.

Brain Research, Journal Year: 2025, Volume and Issue: unknown, P. 149574 - 149574

Published: March 1, 2025

It is traditionally assumed that the corpus callosum has a pivotal role in supporting hemispheric lateralisation, which originated from series of studies suggesting differences callosal morphology relation to handedness. However, recent systematic reviews document are only inconsistently reported, and it been speculated these inconsistencies might arise focussing on handedness alone, without considering other lateralized functional modules. To address this short-coming, present pre-registered study was designed re-examine possible effects while hand preference interaction with dominance for language. predicted those individuals who write ipsilateral their language dominant hemisphere, have an increased need interhemispheric integration reflected detectable alteration morphology. That is, individual writing left (LW) being (LLD) larger or thicker than motor production controlled by same hemisphere. We tested prediction comparing between three common groups result when combing preferred (LW vs. right writers, RW) hemisphere processing. For purpose, (LLD dominance, RLD) determined using verbal-fluency task magnetic resonance (fMRI) previously validated. The included N = 220 participants both sexes, 97 were classified as LW/LLD, 73 RW/LLD, 50 LW/RLD. assessed T1-weighted structural MR images midsagittal surface area (subdivided into subregions genu, truncus, posterior third) well regional thickness (at 100 measuring points). statistical analyses did not reveal any evidence support our predictions sample size provides sufficient test power rule out comparatively small reasonable confidence. Thus, appears substantially affected supposed requirement LW/LLD compared RW/LLD LW/RLD individuals.

Language: Английский

Citations

0