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Altered white matter microstructure underlies listening difficulties in children suspected of auditory processing disorders: a DTI study.

Farah R, Schmithorst VJ, Keith RW, Holland SK - Brain Behav (2014)

Bottom Line: Listening difficulties were associated with altered white matter microstructure, reflected by decreased FA in frontal multifocal white matter regions centered in prefrontal cortex bilaterally and left anterior cingulate.Furthermore, listening difficulties were associated with increased MD (with increase in both RD and AD) in the posterior limb of the internal capsule (sublenticular part) at the auditory radiations where auditory input is transmitted between the thalamus and the auditory cortex.Our results provide direct evidence that listening difficulties in children are associated with altered white matter microstructure and that both sensory and supramodal deficits underlie the differences between the groups.

View Article: PubMed Central - PubMed

Affiliation: Communication Sciences Research Center, Cincinnati Children's Hospital Medical Center Cincinnati, Ohio ; Department of Communication Sciences and Disorders, College of Allied Health Sciences, University of Cincinnati Cincinnati, Ohio.

ABSTRACT

Introduction: The purpose of the present study was to identify biomarkers of listening difficulties by investigating white matter microstructure in children suspected of auditory processing disorder (APD) using diffusion tensor imaging (DTI). Behavioral studies have suggested that impaired cognitive and/or attention abilities rather than a pure sensory processing deficit underlie listening difficulties and auditory processing disorder (APD) in children. However, the neural signature of listening difficulties has not been investigated.

Methods: Twelve children with listening difficulties and atypical left ear advantage (LEA) in dichotic listening and twelve age- and gender-matched typically developing children with typical right ear advantage (REA) were tested. Using voxel-based analysis, fractional anisotropy (FA), and mean, axial and radial diffusivity (MD, AD, RD) maps were computed and contrasted between the groups.

Results: Listening difficulties were associated with altered white matter microstructure, reflected by decreased FA in frontal multifocal white matter regions centered in prefrontal cortex bilaterally and left anterior cingulate. Increased RD and decreased AD accounted for the decreased FA, suggesting delayed myelination in frontal white matter tracts and disrupted fiber organization in the LEA group. Furthermore, listening difficulties were associated with increased MD (with increase in both RD and AD) in the posterior limb of the internal capsule (sublenticular part) at the auditory radiations where auditory input is transmitted between the thalamus and the auditory cortex.

Conclusions: Our results provide direct evidence that listening difficulties in children are associated with altered white matter microstructure and that both sensory and supramodal deficits underlie the differences between the groups.

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Related in: MedlinePlus

Regions with significant mean diffusivity (MD). Difference between the left ear advantage (LEA) and the right ear advantage (REA) group (hot colors =LEA>REA; cold colors = LEA < REA) in a cohort of 24 children age 7–14 years old. Slice locations range from z = 18 to 33. All images are in radiological orientation.
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fig02: Regions with significant mean diffusivity (MD). Difference between the left ear advantage (LEA) and the right ear advantage (REA) group (hot colors =LEA>REA; cold colors = LEA < REA) in a cohort of 24 children age 7–14 years old. Slice locations range from z = 18 to 33. All images are in radiological orientation.

Mentions: Mean diffusivity contrast analyses between the groups demonstrated two clusters with statistically significant group differences (P < 0.01, corrected). None of the clusters showing significant FA differences demonstrated any MD changes. However, the LEA group showed significantly increased MD in temporal white matter (the cluster centroid was closest to the transverse temporal gyrus [TTG], BA41) and decreased MD in temporal white matter (BA37; see Table 3; Fig. 2). Increased MD in TTG was accounted for by increase in both RD and AD. Again, visual inspection of this region along with the MRI white matter atlas revealed that this white matter region constituted the retrolenticular part of the internal capsule. However, the atlas does not distinguish between the retrolenticular and sublenticular parts.


Altered white matter microstructure underlies listening difficulties in children suspected of auditory processing disorders: a DTI study.

Farah R, Schmithorst VJ, Keith RW, Holland SK - Brain Behav (2014)

Regions with significant mean diffusivity (MD). Difference between the left ear advantage (LEA) and the right ear advantage (REA) group (hot colors =LEA>REA; cold colors = LEA < REA) in a cohort of 24 children age 7–14 years old. Slice locations range from z = 18 to 33. All images are in radiological orientation.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4128035&req=5

fig02: Regions with significant mean diffusivity (MD). Difference between the left ear advantage (LEA) and the right ear advantage (REA) group (hot colors =LEA>REA; cold colors = LEA < REA) in a cohort of 24 children age 7–14 years old. Slice locations range from z = 18 to 33. All images are in radiological orientation.
Mentions: Mean diffusivity contrast analyses between the groups demonstrated two clusters with statistically significant group differences (P < 0.01, corrected). None of the clusters showing significant FA differences demonstrated any MD changes. However, the LEA group showed significantly increased MD in temporal white matter (the cluster centroid was closest to the transverse temporal gyrus [TTG], BA41) and decreased MD in temporal white matter (BA37; see Table 3; Fig. 2). Increased MD in TTG was accounted for by increase in both RD and AD. Again, visual inspection of this region along with the MRI white matter atlas revealed that this white matter region constituted the retrolenticular part of the internal capsule. However, the atlas does not distinguish between the retrolenticular and sublenticular parts.

Bottom Line: Listening difficulties were associated with altered white matter microstructure, reflected by decreased FA in frontal multifocal white matter regions centered in prefrontal cortex bilaterally and left anterior cingulate.Furthermore, listening difficulties were associated with increased MD (with increase in both RD and AD) in the posterior limb of the internal capsule (sublenticular part) at the auditory radiations where auditory input is transmitted between the thalamus and the auditory cortex.Our results provide direct evidence that listening difficulties in children are associated with altered white matter microstructure and that both sensory and supramodal deficits underlie the differences between the groups.

View Article: PubMed Central - PubMed

Affiliation: Communication Sciences Research Center, Cincinnati Children's Hospital Medical Center Cincinnati, Ohio ; Department of Communication Sciences and Disorders, College of Allied Health Sciences, University of Cincinnati Cincinnati, Ohio.

ABSTRACT

Introduction: The purpose of the present study was to identify biomarkers of listening difficulties by investigating white matter microstructure in children suspected of auditory processing disorder (APD) using diffusion tensor imaging (DTI). Behavioral studies have suggested that impaired cognitive and/or attention abilities rather than a pure sensory processing deficit underlie listening difficulties and auditory processing disorder (APD) in children. However, the neural signature of listening difficulties has not been investigated.

Methods: Twelve children with listening difficulties and atypical left ear advantage (LEA) in dichotic listening and twelve age- and gender-matched typically developing children with typical right ear advantage (REA) were tested. Using voxel-based analysis, fractional anisotropy (FA), and mean, axial and radial diffusivity (MD, AD, RD) maps were computed and contrasted between the groups.

Results: Listening difficulties were associated with altered white matter microstructure, reflected by decreased FA in frontal multifocal white matter regions centered in prefrontal cortex bilaterally and left anterior cingulate. Increased RD and decreased AD accounted for the decreased FA, suggesting delayed myelination in frontal white matter tracts and disrupted fiber organization in the LEA group. Furthermore, listening difficulties were associated with increased MD (with increase in both RD and AD) in the posterior limb of the internal capsule (sublenticular part) at the auditory radiations where auditory input is transmitted between the thalamus and the auditory cortex.

Conclusions: Our results provide direct evidence that listening difficulties in children are associated with altered white matter microstructure and that both sensory and supramodal deficits underlie the differences between the groups.

Show MeSH
Related in: MedlinePlus