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Robert L Slevc - One of the best experts on this subject based on the ideXlab platform.
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chapter 32 auditory agnosia
Handbook of Clinical Neurology, 2015Co-Authors: Robert L Slevc, Alison R. ShellAbstract:Auditory agnosia refers to impairments in sound perception and identification despite intact hearing, cognitive functioning, and language abilities (reading, writing, and speaking). Auditory agnosia can be general, affecting all types of sound perception, or can be (relatively) specific to a particular domain. Verbal auditory agnosia (also known as (Pure) Word Deafness) refers to deficits specific to speech processing, environmental sound agnosia refers to difficulties confined to non-speech environmental sounds, and amusia refers to deficits confined to music. These deficits can be apperceptive, affecting basic perceptual processes, or associative, affecting the relation of a perceived auditory object to its meaning. This chapter discusses what is known about the behavioral symptoms and lesion correlates of these different types of auditory agnosia (focusing especially on verbal auditory agnosia), evidence for the role of a rapid temporal processing deficit in some aspects of auditory agnosia, and the few attempts to treat the perceptual deficits associated with auditory agnosia. A clear picture of auditory agnosia has been slow to emerge, hampered by the considerable heterogeneity in behavioral deficits, associated brain damage, and variable assessments across cases. Despite this lack of clarity, these striking deficits in complex sound processing continue to inform our understanding of auditory perception and cognition.
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speech perception rapid temporal processing and the left hemisphere a case study of unilateral Pure Word Deafness
Neuropsychologia, 2011Co-Authors: Robert L Slevc, Randi C Martin, Cris A Hamilton, Marc F JoanisseAbstract:The mechanisms and functional anatomy underlying the early stages of speech perception are still not well understood. One way to investigate the cognitive and neural underpinnings of speech perception is by investigating patients with speech perception deficits but with preserved ability in other domains of language. One such case is reported here: patient NL shows highly impaired speech perception despite normal hearing ability and preserved semantic knowledge, speaking, and reading ability, and is thus classified as a case of Pure Word Deafness (PWD). NL has a left temporoparietal lesion without right hemisphere damage and DTI imaging suggests that he has preserved cross-hemispheric connectivity, arguing against an account of PWD as a disconnection of left lateralized language areas from auditory input. Two experiments investigated whether NL's speech perception deficit could instead result from an underlying problem with rapid temporal processing. Experiment 1 showed that NL has particular difficulty discriminating sounds that differ in terms of rapid temporal changes, be they speech or non-speech sounds. Experiment 2 employed an intensive training program designed to improve rapid temporal processing in language impaired children (Fast ForWord; Scientific Learning Corporation, Oakland, CA) and found that NL was able to improve his ability to discriminate rapid temporal differences in non-speech sounds, but not in speech sounds. Overall, these data suggest that patients with unilateral PWD may, in fact, have a deficit in (left lateralized) temporal processing ability, however they also show that a rapid temporal processing deficit is, by itself, unable to account for this patient's speech perception deficit.
M Isabelle D Rapin - One of the best experts on this subject based on the ideXlab platform.
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verbal auditory agnosia in children
Developmental Medicine & Child Neurology, 2008Co-Authors: M Isabelle D RapinAbstract:SUMMARY Four (possibly five) boys are described with a profound comprehension deficit for acoustic language, leading to severe or complete abolition of expressive speech. One boy had presumed megalencephaly from birth but was of superior intelligence. He had a severe articulation deficit from early childhood, with delayed acquisition of speech. Another boy is thought to have a small angiomatous anomaly in the depth of the left parietal lobe. No brain lesions are known in the other three. Evidence for bilateral brain dysfunction consists of minor motor abnormalities in three boys, oromotor deficits in two boys, and bilaterally synchronous diffuse or independent focal paroxysmal discharges in the eeg of three, possibly four, of the boys. Seizures have occurred in only three boys, and have been easily controlled with anticonvulsants. One boy with a grossly abnormal eeg has had no clinical seizures to date and has not benefited from one year of anticonvulsant therapy. Two of the boys are brothers, including the boy in whom the diagnosis is questionable since speech was never normal and since he has had neither seizures nor an abnormal eeg. The severity of eeg abnormalities did not correlate closely with the course of the language deficit. The relationship of this syndrome to acquired aphasia in children, to Wernicke's aphasia and Pure Word Deafness in adults, and to developmental language disability with predominantly receptive deficits, is discussed. One child illustrated the close association between writing and phonologic encoding and decoding operations, and two children the preservation of linguistic skills provided the acoustic channel was by-passed and language presented visually. This latter point has been emphasized because of its implications for the remedial education of children with this syndrome. RESUMEN Agnosie verbo-auditive de l'enfance L'article rapporte quatre, peut-ětre cinq, observations de garcons presentant un deficit severe de comprehension du langage acoustique, conduisant a une abolition severe ou complete de l'expression parlee. L'un des garcons presentait probablement une megalencephalie depuis la naissance mais etait d'intelligence superieure. II eut un deficit severe de l'articulation depuis la premiere enfance avec un retard d'acquisition du langage. Une petite anomalie angiomateuse dans la profondeur du lobe parietal gauche etait suspectee chez un autre garcon mais aucune lesion cerebrale n'etait connue chez les trois autres. Des manifestations de disfonction bilaterale du cerveau se traduisaient par des anomalies motrices mineures chez trois garcons, des deficits oromoteurs chez deux garcons et chez trois, peut-ětre quatre garcons, des decharges paroxystiques a l'EEG, soit bilaterales synchrones et diffuses, soit focales et independantes. Des crises se sont manifestees seulement chez trois garcons facilement controlees par les anti-comitiaux. Un garcon avec un EEG grossierement anormal n'a presente jusqu'a ce jour aucune crise clinique et n'a pas benefucie d'une therapeutique anti-comitiale pendant un an. Deux des garcons etaient freres comprenant celui chez qui le diagnostic est sujet a caution, le langage n'ayant jamais ete normal et en l'absence de crise ou d'EEG anormal. La gravite des anomalies EEG ne sont pas reliees etroitement a l'allure du deficit de langage. Les auteurs discutent la relation existant entre ce syndrome et l'aphasie acquise de l'enfance, l'aphasie de Wernicke et la surdite verbale de l'adulte, les anomalies developmental de langage avec deficit a predominance receptive. L'un des enfants demontre la relation etroite existant entre l'ecriture et les operations de codage-decodage phonologique; deux autres enfants demontrent la possibilite de conserver l'efficience linguistique lorsque le canal acoustique peut ětre court-circuite par presentation visuelle du langage. Ce dernier point est souligne en raison de son implication pour l'education therapeutique des enfants presentant ce syndrome. ZUSAMMENFASSUNG Verbale Seelentaubheit bei Kindern Vier (moglicherweise funf) Jungen mit einem stark eingeschrankten Verstandnis fur akustisch wahrnehmbare Sprache, was zu schwerem oder ganzlichem Verlust der expressiven Sprache fuhrte, werden beschrieben. Ein Junge hatte vermutlich eine Megalencephalie seit Geburt, war dabei jedoch hochintelligent. Er hatte schwere Artikulationsstorungen seit fruhester Kindheit mit verzogerter Sprachentwicklung. Bei einem anderen Jungen wurde eine kleine Gefasmisbildung am Boden des linken Parietallappens vermutet. Bei den anderen drei Kindern waren keine Hirnlasionen bekannt. Man hatte bei drei Jungen Anhalt fur eine bilaterale cerebrale Dysfunktion, die sich in geringfugigen motorischen Funktionsstorungen auserten, bei zwei Jungen in Storungen der Mundmotorik und bei drei eventuell vier der Jungen in. bilateral synchron auftretenden diffusen oder fokalen paroxysmalen Entladungen im eeg. Nur bei drei Jungen wurden Krampfanfalle beobachtet, die durch antikonvulsive Medikation problemlos unter Kontrolle gebracht werden konnten. Ein Junge mit einem schwer abnormen eeg hatte bisher keine klinischen Anfalle und das eeg war nach einem Jahr antikonvulsiver Behandlung unverandert. Zwei der Jungen sind Bruder, bei einem davon ist die Diagnose zweifelhaft, da die Sprache nie normal war und er weder Anfalle noch ein pathologisches eeg hatte. Die Schwere der EEG-Veranderungen korrelierte nicht direkt mit dem Verlauf der Sprachstorungen. Die Bezugspunkte dieses Syndromszu erworbener Aphasie im Kindesalter, zu Wernicke's Aphasie und zu reiner Worttaubheit beim Erwachsenen und zu Sprachentwicklungsstorun-gen mit vorwiegenden Storungen der Perception, wurden diskutiert. Ein Kind veranschaulichte die enge Beziehung zwischen Ver- und Entschlusseln von Schrift und Sprache und zwei Kinder die Erhaltung der linguistischen Fahigkeiten, vorausgesetzt der akustische Weg wurde umgangen und die Sprache visuell dargebracht. Der letzte Punkt wird sehr unterstrichen, da er fur die Heilerziehung der Kinder mit diesem Syndrom sehr wichtig ist. RESUMEN Agnosia verbal auditiva en ninos Se describen cuatro (posiblemente cinco) ninos con un profundo deficit de comprension para el lenguaje acustico, que conducia a una abolicion grave o completa del lenguaje expresivo. Un muchacho al parecer presentaba megalencefalia desde el nacimiento pero era de inteligencia superior. Tenia un deficit grave de articulacion desde la primera infancia con un retraso en la adquisicion del habla. Otro muchacho se piensa que tenia una pequena anomalia angiomatosa en la profundidad del lobulo parietal izquierdo. En los otros casos no se conoce ninguna lesion cerebral. La evidencia de una disfuncion cerebral bilateral consiste en la presencia de pequenas anomalias motoras en tres ninos, deficits oromotores en dos chicos, y descargas focales paroxisticas difusas o independientes bilaterales y sincronas en el EEG de tres, posiblemente cuatro, de los chicos. Convulsiones solo tuvieron lugar en tres chicos y habian sido facilmente controladas con anticonvulsivantes. Un muchacho con una anomalia EEG grosera no habia tenido crisis clinicas hasta el momento y no se habia beneficiado de una terapia anticonvulsivante seguida durante un ano. Dos de los chicos son hermanos incluyendo el chico en el que el diagnostico es cuestionable puesto que el lenguaje no habia sido nunca normal y no habia presentado nunca ataques ni un EEG anormal. La gravedad de las anomalias en el EEG no se correlacionaban de cerca con el curso del deficit en el lenguaje. La relacion de este sindrome con la afasia adquirida en ninos, con la afasia de Wernicke y la sordera verbal pura del adulto y con la dificultad de desarrollo del lenguaje con deficits predominantemente receptivos son discutidos en esa comunicacion. Un nino ilustraba la asociacion cercana entre las operaciones de codification y decodificacion en la escritura y el habla y dos ninos ilustraban la preservacion de habilidades linguisticas siempre que el canal acustico fuese soslayado y el lenguaje fuese presentado visualmente. Este ultimo punto ha sido puesto de relieve debido a sus implicaciones para la educacion especial de ninos con este sindrome.
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verbal auditory agnosia in children
Developmental Medicine & Child Neurology, 2008Co-Authors: M Isabelle D RapinAbstract:Four (possibly five) boys are described with a profound comprehension deficit for acoustic language, leading to severe or complete abolition of expressive speech. One boy had presumed megalencephaly from birth but was of superior intelligence. He had a severe articulation deficit from early childhood, with delayed acquisition of speech. Another boy is thought to have a small angiomatous anomaly in the depth of the left parietal lobe. No brain lesions are known in the other three. Evidence for bilateral brain dysfunction consists of minor motor abnormalities in three boys, oromotor deficits in two boys, and bilaterally synchronous diffuse or independent focal paroxysmal discharges in the EEG of three, possibly four, of the boys. Seizures have occurred in only three boys, and have been easily controlled with anticonvulsants. One boy with a grossly abnormal EEG has had no clinical seizures to date and has not benefited frome one year of anticonvulsant therapy. Two of the boys are brothers, including the boy in whome the diagnosis is questionable since speech was never normal and since he has had neither seizures for an abnormal EEG. The severity of EEG abnormalities did not correlate closely with the course of the language deficit. The relationship of this syndrome to acquired aphasia in children, to Wernicke's aphasia and Pure Word Deafness in adults, and to developmental lagnuage disability with predominantly receptive deficits, is discussed. One child illustrated the close association between writing and phonologic encoding and decoding operations, and two children the preservation of linguistic skills provided the acoustic channel was by-passed and language presented visually. This latter point has been emphasized because of its implications for the remedial education of children with this syndrome.
Sean Madigan - One of the best experts on this subject based on the ideXlab platform.
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on Pure Word Deafness temporal processing and the left hemisphere
Journal of The International Neuropsychological Society, 2005Co-Authors: Gerry A Stefanatos, Arthur Gershkoff, Sean MadiganAbstract:Pure Word Deafness (PWD) is a rare neurological syndrome characterized by severe difficulties in understanding and reproducing spoken language, with sparing of written language comprehension and speech production. The pathognomonic disturbance of auditory comprehension appears to be associated with a breakdown in processes involved in mapping auditory input to lexical representations of Words, but the functional locus of this disturbance and the localization of the responsible lesion have long been disputed. We report here on a woman with PWD resulting from a circumscribed unilateral infarct involving the left superior temporal lobe who demonstrated significant problems processing transitional spectrotemporal cues in both speech and nonspeech sounds. On speech discrimination tasks, she exhibited poor differentiation of stop consonant-vowel syllables distinguished by voicing onset and brief formant frequency transitions. Isolated formant transitions could be reliably discriminated only at very long durations (>200 ms). By contrast, click fusion threshold, which depends on millisecond-level resolution of brief auditory events, was normal. These results suggest that the problems with speech analysis in this case were not secondary to general constraints on auditory temporal resolution. Rather, they point to a disturbance of left hemisphere auditory mechanisms that preferentially analyze rapid spectrotemporal variations in frequency. The findings have important implications for our conceptualization of PWD and its subtypes. (JINS, 2005, 11, 456–470.)
Marlies Vogtschaden - One of the best experts on this subject based on the ideXlab platform.
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Pure Word Deafness with auditory object agnosia after bilateral lesion of the superior temporal sulcus
Cortex, 2015Co-Authors: Alexander Gutschalk, Stefan Uppenkamp, Bernhard Riedel, Andreas J Bartsch, Tobias Brandt, Marlies VogtschadenAbstract:Based on results from functional imaging, cortex along the superior temporal sulcus (STS) has been suggested to subserve phoneme and pre-lexical speech perception. For vowel classification, both superior temporal plane (STP) and STS areas have been suggested relevant. Lesion of bilateral STS may conversely be expected to cause Pure Word Deafness and possibly also impaired vowel classification. Here we studied a patient with bilateral STS lesions caused by ischemic strokes and relatively intact medial STPs to characterize the behavioral consequences of STS loss. The patient showed severe deficits in auditory speech perception, whereas his speech production was fluent and communication by written speech was grossly intact. Auditory-evoked fields in the STP were within normal limits on both sides, suggesting that major parts of the auditory cortex were functionally intact. Further studies showed that the patient had normal hearing thresholds and only mild disability in tests for telencephalic hearing disorder. Prominent deficits were discovered in an auditory-object classification task, where the patient performed four standard deviations below the control group. In marked contrast, performance in a vowel-classification task was intact. Auditory evoked fields showed enhanced responses for vowels compared to matched non-vowels within normal limits. Our results are consistent with the notion that cortex along STS is important for auditory speech perception, although it does not appear to be entirely speech specific. Formant analysis and single vowel classification, however, appear to be already implemented in auditory cortex on the STP.
Marc F Joanisse - One of the best experts on this subject based on the ideXlab platform.
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speech perception rapid temporal processing and the left hemisphere a case study of unilateral Pure Word Deafness
Neuropsychologia, 2011Co-Authors: Robert L Slevc, Randi C Martin, Cris A Hamilton, Marc F JoanisseAbstract:The mechanisms and functional anatomy underlying the early stages of speech perception are still not well understood. One way to investigate the cognitive and neural underpinnings of speech perception is by investigating patients with speech perception deficits but with preserved ability in other domains of language. One such case is reported here: patient NL shows highly impaired speech perception despite normal hearing ability and preserved semantic knowledge, speaking, and reading ability, and is thus classified as a case of Pure Word Deafness (PWD). NL has a left temporoparietal lesion without right hemisphere damage and DTI imaging suggests that he has preserved cross-hemispheric connectivity, arguing against an account of PWD as a disconnection of left lateralized language areas from auditory input. Two experiments investigated whether NL's speech perception deficit could instead result from an underlying problem with rapid temporal processing. Experiment 1 showed that NL has particular difficulty discriminating sounds that differ in terms of rapid temporal changes, be they speech or non-speech sounds. Experiment 2 employed an intensive training program designed to improve rapid temporal processing in language impaired children (Fast ForWord; Scientific Learning Corporation, Oakland, CA) and found that NL was able to improve his ability to discriminate rapid temporal differences in non-speech sounds, but not in speech sounds. Overall, these data suggest that patients with unilateral PWD may, in fact, have a deficit in (left lateralized) temporal processing ability, however they also show that a rapid temporal processing deficit is, by itself, unable to account for this patient's speech perception deficit.
