Quarterly Began with v. 1, no. 1 (Oct. 1847). -v. 31, no. 3 (July 1886). Published in: Washington, D.C., -1886. Publication suspended Oct. 1849-July 1850 and Sept. 1861-June 1868. Issued Oct. ...1847-July 1849 by the American Asylum for the Deaf and Dumb; Oct. 1850-July 1886 by the Convention of American Instructors of the Deaf and Dumb. Indexes: Vols. 1 (1847)-20 (1875) in 1 v.; v. 21 (1876)-30 (1886) in 1 v.; v. 31 (1886)-40 (1895) of later title in 1 v. Description based on: Vol. 1, no. 2 (Jan. 1848); title from caption. American annals of the deaf 0002-726X (DLC) 15014404 (OCoLC)5695496
This review explores cross-modal cortical plasticity as a result of auditory deprivation in populations with hearing loss across the age spectrum, from development to adulthood. Cross-modal ...plasticity refers to the phenomenon when deprivation in one sensory modality (e.g. the auditory modality as in deafness or hearing loss) results in the recruitment of cortical resources of the deprived modality by intact sensory modalities (e.g. visual or somatosensory systems). We discuss recruitment of auditory cortical resources for visual and somatosensory processing in deafness and in lesser degrees of hearing loss. We describe developmental cross-modal re-organization in the context of congenital or pre-lingual deafness in childhood and in the context of adult-onset, age-related hearing loss, with a focus on how cross-modal plasticity relates to clinical outcomes. We provide both single-subject and group-level evidence of cross-modal re-organization by the visual and somatosensory systems in bilateral, congenital deafness, single-sided deafness, adults with early-stage, mild-moderate hearing loss, and individual adult and pediatric patients exhibit excellent and average speech perception with hearing aids and cochlear implants. We discuss a framework in which changes in cortical resource allocation secondary to hearing loss results in decreased intra-modal plasticity in auditory cortex, accompanied by increased cross-modal recruitment of auditory cortices by the other sensory systems, and simultaneous compensatory activation of frontal cortices. The frontal cortices, as we will discuss, play an important role in mediating cognitive compensation in hearing loss. Given the wide range of variability in behavioral performance following audiological intervention, changes in cortical plasticity may play a valuable role in the prediction of clinical outcomes following intervention. Further, the development of new technologies and rehabilitation strategies that incorporate brain-based biomarkers may help better serve hearing impaired populations across the lifespan.
•We describe evidence of cross-modal plasticity by vision and somatosenation in children and adults with hearing loss.•We describe evidence of compensatory activation of frontal cortices in hearing loss.•We describe applications of cross-modal plasticity in clinical populations with hearing loss.
The modern cochlear implant (CI) is the most successful neural prosthesis developed to date. CIs provide hearing to the profoundly hearing impaired and allow the acquisition of spoken language in ...children born deaf. Results from studies enabled by the CI have provided new insights into (
) minimal representations at the periphery for speech reception, (
) brain mechanisms for decoding speech presented in quiet and in acoustically adverse conditions, (
) the developmental neuroscience of language and hearing, and (
) the mechanisms and time courses of intramodal and cross-modal plasticity. Additionally, the results have underscored the interconnectedness of brain functions and the importance of top-down processes in perception and learning. The findings are described in this review with emphasis on the developing brain and the acquisition of hearing and spoken language.
Fragestellung: Gute 3D-Darstellungen der Cochlea sind mit geringem Zeitaufwand aus MRT- Routinesequenzen zu erstellen. Bringt die 3D-Darstellung bei Fehlbildungen eine Zusatzinformation im Vergleich ...zur Schichtbildinterpretation? Methode: Retrospektive Auswertung von 31 fehlgebildeten Innenohren. Beurteilt wurden folgende bildmorphologische Merkmale: Nerven, cochleare Apertur, Modiolus, basale und Apikale Windungen, Skala tympani und vestibuli, cochleovestibularer Ubergang, Form/ Auspragung von Vestibulum und Bogengangen sowie mogliche Zusatzinformation. An Schichtbildern und 3D-Modellen erfolgen standardisierte Messungen. Ergebnis: Es wurden 8 IPT1, 7 Hypoplasien, 5 Bogengangsaplasien, 2 cochleare Aplasien, 3 LVAS, 2 X-linked deafness und 4 IAC-Fehlbildungen bei Goldenhar eingeschlossen. Der knocherne Verschluss der Apertura cochlea und die Nerven im IAC sind am Schichtbild eindeutiger beurteilbar. Die Weite des Ubergangs von der Cochlea zum Vestibulum, der Modiolus und die apikalen Windungen sind in beiden Verfahren vergleichbar auszuwerten. Eine cochleare Hypoplasie oder eine verkurzte basale Windung, die raumlichen Lage der fehlgebildeten Bogengange oder die Dysplasie des Duktus cochlearis sind am 3D-Modell schneller und besser zu erfassen. Die Langen der Cochleae reichen von 15 bis 34,1 mm. Schlussfolgerung: Das 3D-Modell kann die Information der Schichtbilder nicht ersetzen, jedoch liefert es bei Innenohrfehlbildungen wertvolle Erganzungen der raumlichen Auspragung und erleichtert die objektorientierte Vermessung der Cochlea. Eine Einordnung von Fehlbildungen wird hiermit erleichtert.
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