Auditory processing studied prospectively in two hemidecorticectomy patients.

Dana Boatman; Eileen P Vining; John Freeman; Benjamin Carson

doi:10.1177/08830738030180030101

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Auditory processing studied prospectively in two hemidecorticectomy patients.

Dana Boatman·Eileen P Vining·John Freeman·Benjamin Carson

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Abstract

Auditory processing of speech and nonspeech sounds was studied prospectively in two hemidecorticectomy patients (ages 10-11 years) with Rasmussen's syndrome. We tested auditory word recognition under four listening conditions: in quiet, in noise, after acoustic filtering, and dichotically. Recognition of environmental sounds and discrimination of tones and digitized syllables were also tested. Presurgical testing confirmed normal processing of speech and nonspeech, for both patients, under all listening conditon. One year after surgery, both patients demonstrated intact recognition of words and environmental sounds in quiet but impaired word recognition in noise. The left hemidecorticectomy patient also demonstrated impaired recognition of low-pass filtered words. These findings suggest that either hemisphere can process speech or nonspeech sounds in quiet, whereas both hemispheres are needed to process speech in background noise. Hemispheric contributions to processing speech in noise appear to differ, with the left hemisphere compensating for loss of phonologic information and the right hemisphere compensating for increased attention demands.

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Acoustic Stimulation Attention Auditory Perception Cerebral Cortex Child Encephalitis Female Functional Laterality Hemispherectomy Humans Noise Pitch Discrimination Prospective Studies Speech Perception Case Reports Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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Dana Boatman, Eileen P Vining, John Freeman, Benjamin Carson. 2003. Auditory processing studied prospectively in two hemidecorticectomy patients.. https://doi.org/10.1177/08830738030180030101

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