Neuroanatomic differences in children with unilateral sensorineural hearing loss detected using functional magnetic resonance imaging.
OBJECTIVE
Functional magnetic resonance imaging (fMRI) provides information about neuronal excitation by measuring changes in cerebral hemodynamics. This study used fMRI to compare neuroanatomic activation patterns in children with unilateral sensorineural hearing loss (USNHL) with the neuroanatomic activation patterns in normally hearing individuals.


METHODS
Patients were presented with narrowband noise and speech-in-noise tasks while undergoing fMRI of the brain. In the narrowband noise task, 5 chirps at center frequencies of 250 Hz, 500 Hz, 1 kHz, 2 kHz, and 4 kHz were presented monaurally for 1 second in a randomized order to children in both groups. In the speech-in-noise task, Bamford-Kowal-Bench (BKB) sentences were presented over 4-talker babble to both ears, and scans were acquired after each stimulus. We compared fMRI data across groups using independent component analysis and Bayesian (hierarchical) linear models.


METHODS
Tertiary referral center.


METHODS
Twelve children with USNHL and 23 normally hearing controls.


METHODS
Perform fMRI while subject listens to narrowband and speech-in-noise tasks.


METHODS
Neuroanatomic differences in fMRI.


RESULTS
In the narrowband noise task, children with USNHL had less activation of auditory areas and failed to activate auditory association areas and attention networks compared with normally hearing controls. In the speech-in-noise task, children with USNHL activated only secondary auditory processing areas in the left hemisphere, while controls activated these areas bilaterally. Children with right-sided USNHL failed to activate attention areas that were activated in controls and in children with left-sided USNHL. Only children with left-sided USNHL activated bilateral visual association areas.


CONCLUSIONS
Results show significant differences in the cortical processing of sound between children with severe to profound USNHL and normally hearing children. These differences may account for the functional auditory problems that children with USNHL experience.
Propst
Evan J
EJ
Division of Pediatric Otolaryngology-Head and Neck Surgery, Cincinnati Children's Hospital Medical Center, MLC 2018, 3333 Burnet Ave, Cincinnati, OH 45229-3039, USA. evan.propst@cchmc.org
Greinwald
John H
JH
Schmithorst
Vincent
V
D000161:Acoustic Stimulation; D001303:Auditory Cortex / Q000033:anatomy & histology / Q000503:physiopathology*; D001499:Bayes Theorem; D001931:Brain Mapping; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000503:physiopathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male