Heschl’s gyrification pattern is related to speech-listening hemispheric lateralization: FMRI investigation in 281 healthy volunteers
Brain Struct Funct. 2014-03-18; 220(3): 1585-1599
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1. Brain Struct Funct. 2015;220(3):1585-99. doi: 10.1007/s00429-014-0746-4. Epub
2014 Mar 18.
Heschl’s gyrification pattern is related to speech-listening hemispheric
lateralization: FMRI investigation in 281 healthy volunteers.
Tzourio-Mazoyer N(1), Marie D, Zago L, Jobard G, Perchey G, Leroux G, Mellet E,
Joliot M, Crivello F, Petit L, Mazoyer B.
(1)GIN, Groupe d’Imagerie Neurofonctionnelle UMR5296, Univ. Bordeaux, Bât. PQR,
CHU Pellegrin, 33000, Bordeaux, France, .
This study investigates the structure-function relationships between the anatomy
of Heschl’s gyri (HG) and speech hemispheric lateralization in 281 healthy
volunteers (135 left-handers). Hemispheric lateralization indices (HFLIs) were
calculated with Wilke’s method from the activations obtained via functional
magnetic resonance imaging while listening to lists of words (LIST). The mean
HFLI during LIST was rightward asymmetrical, and left-handers displayed a trend
toward decreased rightward asymmetry. The correlations between LIST BOLD contrast
maps and individual HFLIs demonstrated that among the cortical areas showing
significant asymmetry during LIST, only phonological regions explained HFLI
variability. Significant positive correlations were present among the left HG,
supramarginal gyri, and the anterior insula. Significant negative correlations
occurred in the mid-part of the right superior temporal sulcus. Left HG had the
largest functional activity during LIST and explained 10% of the HFLI variance.
There was a strong anatomo-functional link in the HG: duplication was associated
with a decrease in both the surface area of the anterior HG and HG functional
activity. Participants with a single left HG exhibited leftward anatomical and
functional asymmetry of HG, but participants with a left duplication lost either
anatomical and/or functional leftward asymmetries. Finally, manual preference was
related to HG anatomy, but not to HG functional asymmetries measured during LIST.
The anatomical characteristics of left-handers (lower occurrence of right HG
duplication and a smaller surface area of the right first HG) thus appeared to be
unrelated to variations in speech lateralization with handedness.
PMID: 24638878 [Indexed for MEDLINE]