Morphometric differences in the Heschl's gyrus of hearing impaired and normal hearing infants.
This study investigates the morphometry of Heschl's gyrus and its included primary auditory cortex (PAC) in hearing impaired (HI) and normal hearing (NH) infants. Fourty-two infants, age 8-19 months, with NH (n = 26) or hearing impairment (n = 16) were studied using high-resolution 3D magnetic resonance imaging. Gray matter (GM) and white matter (WM) volumes were obtained using software for automatic brain imaging segmentation to estimate the volume of each tissue within manually defined regions for the anterior portion of Heschl's gyrus (aHG) in each individual subject, transformed to an infant brain template space. Interactions among group (HI, NH), tissue type (GM, WM), and hemisphere (left, right) were examined using analysis of variance. Whole-brain voxel-based morphometry was utilized to explore volume differences between groups across the entire brain. The HI group showed increased GM and decreased WM in aHG compared with the NH group; likely effects of auditory deprivation. The HI group did not exhibit their typical L > R asymmetry pattern that the NH group showed. Increased GM in aHG in HI infants may represent abnormal cortical development in PAC as seen in animal models of sensory deprivation. Lower WM volume is consistent with studies with deaf adults.
Smith
Kristen M
KM
Pediatric Neuroimaging Research Consortium, Cincinnati Children's Research Foundation, Cincinnati, OH, USA.
Mecoli
Marc D
MD
Altaye
Mekibib
M
Komlos
Marcia
M
Maitra
Raka
R
Eaton
Ken P
KP
Egelhoff
John C
JC
Holland
Scott K
SK
D001284:Atrophy; D001303:Auditory Cortex / Q000033:anatomy & histology / Q000254:growth & development* / Q000473:pathology*; D001931:Brain Mapping / Q000379:methods; D003638:Deafness / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D012016:Reference Values; D012683:Sensory Deprivation / Q000502:physiology*