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Kimitaka Kaga - One of the best experts on this subject based on the ideXlab platform.
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subcortical deafness as a subtype of Auditory Agnosia after injury of bilateral Auditory radiations caused by two cerebrovascular accidents normal Auditory brainstem responses with i vii waves and abolished consciousness of hearing
Acta Oto-laryngologica, 2021Co-Authors: Ryohei Akiyoshi, Mitsuko Shindo, Kimitaka KagaAbstract:In central Auditory disorders caused by damage of the cerebral hemispheres, there are cortical deafness and Auditory Agnosia. Although clinical cases of cortical deafness have been reported, little...
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Auditory Agnosia in children due to herpes encephalitis
2021Co-Authors: Kimitaka KagaAbstract:Five pediatric patients whose bilateral Auditory cortices were damaged by herpes encephalitis at an early age were studied. Their brain CT and MRI scans demonstrated common bilateral lesions of the Auditory cortices. Their Auditory perception was evaluated by means of behavioral and objective hearing tests and Auditory perception tests. Four patients showed mild or moderate hearing loss in the behavioral hearing test and on their ABRs but they did not manifest total deafness. Moreover, perception tests involving speech, environmental sounds, and music demonstrated that Auditory perception ability had been mostly lost in all patients. On reaching school age, the patients were enrolled in schools for the deaf or special schools for handicapped children. A patient who was followed up for over 30 years ultimately showed profound hearing loss.
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Auditory Agnosia due to long term severe hydrocephalus caused by spina bifida specific Auditory pathway versus nonspecific Auditory pathway
Acta Oto-laryngologica, 2011Co-Authors: Qing Zhang, Kimitaka Kaga, Akimasa HayashiAbstract:AbstractA 27-year-old female showed Auditory Agnosia after long-term severe hydrocephalus due to congenital spina bifida. After years of hydrocephalus, she gradually suffered from hearing loss in her right ear at 19 years of age, followed by her left ear. During the time when she retained some ability to hear, she experienced severe difficulty in distinguishing verbal, environmental, and musical instrumental sounds. However, her Auditory brainstem response and distortion product otoacoustic emissions were largely intact in the left ear. Her bilateral Auditory cortices were preserved, as shown by neuroimaging, whereas her Auditory radiations were severely damaged owing to progressive hydrocephalus. Although she had a complete bilateral hearing loss, she felt great pleasure when exposed to music. After years of self-training to read lips, she regained fluent ability to communicate. Clinical manifestations of this patient indicate that Auditory Agnosia can occur after long-term hydrocephalus due to spina bif...
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magnetoencephalography and positron emission tomography studies of a patient with Auditory Agnosia caused by bilateral lesions confined to the Auditory radiations
Acta Oto-laryngologica, 2005Co-Authors: Kimitaka Kaga, Mitsuko Shindo, Masako Nakamura, Takahide Kurauchi, Kenji IshiiAbstract:The aim of this study was to investigate Auditory cortex function in the context of Auditory stimuli in a patient with Auditory Agnosia due to bilateral lesions confined to the Auditory radiations. A male patient experienced mild left temporal hemiplegia because of right putaminal hemorrhage at the age of 43 years. Thereafter he recovered completely but hypertension persisted. When he was 53 years old, he suffered left putaminal hemorrhage and went into a coma. After recovering from the coma and right hemiplegia he could hear but could not discriminate speech sounds. Brain CT and MRI demonstrated small bilateral lesions confined to the Auditory radiations. Magnetoencephalography demonstrated the disappearance of middle latency responses and Auditory-evoked potential studies showed a very small Pa peak. In contrast, a positron emission tomography study demonstrated a marked increase in blood flow in the bilateral Auditory cortex in response to both click and monosyllable stimuli. It is speculated that the ...
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magnetoencephalography and positron emission tomography studies of a patient with Auditory Agnosia caused by bilateral lesions confined to the Auditory radiations
Acta Oto-laryngologica, 2005Co-Authors: Kimitaka Kaga, Mitsuko Shindo, Masako Nakamura, Takahide Kurauchi, Kenji IshiiAbstract:The aim of this study was to investigate Auditory cortex function in the context of Auditory stimuli in a patient with Auditory Agnosia due to bilateral lesions confined to the Auditory radiations. A male patient experienced mild left temporal hemiplegia because of right putaminal hemorrhage at the age of 43 years. Thereafter he recovered completely but hypertension persisted. When he was 53 years old, he suffered left putaminal hemorrhage and went into a coma. After recovering from the coma and right hemiplegia he could hear but could not discriminate speech sounds. Brain CT and MRI demonstrated small bilateral lesions confined to the Auditory radiations. Magnetoencephalography demonstrated the disappearance of middle latency responses and Auditory-evoked potential studies showed a very small Pa peak. In contrast, a positron emission tomography study demonstrated a marked increase in blood flow in the bilateral Auditory cortex in response to both click and monosyllable stimuli. It is speculated that the Auditory cortex receives functional projections from the cochlea via non-specific pathways in the cerebral hemispheres.
Mitsuko Shindo - One of the best experts on this subject based on the ideXlab platform.
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subcortical deafness as a subtype of Auditory Agnosia after injury of bilateral Auditory radiations caused by two cerebrovascular accidents normal Auditory brainstem responses with i vii waves and abolished consciousness of hearing
Acta Oto-laryngologica, 2021Co-Authors: Ryohei Akiyoshi, Mitsuko Shindo, Kimitaka KagaAbstract:In central Auditory disorders caused by damage of the cerebral hemispheres, there are cortical deafness and Auditory Agnosia. Although clinical cases of cortical deafness have been reported, little...
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magnetoencephalography and positron emission tomography studies of a patient with Auditory Agnosia caused by bilateral lesions confined to the Auditory radiations
Acta Oto-laryngologica, 2005Co-Authors: Kimitaka Kaga, Mitsuko Shindo, Masako Nakamura, Takahide Kurauchi, Kenji IshiiAbstract:The aim of this study was to investigate Auditory cortex function in the context of Auditory stimuli in a patient with Auditory Agnosia due to bilateral lesions confined to the Auditory radiations. A male patient experienced mild left temporal hemiplegia because of right putaminal hemorrhage at the age of 43 years. Thereafter he recovered completely but hypertension persisted. When he was 53 years old, he suffered left putaminal hemorrhage and went into a coma. After recovering from the coma and right hemiplegia he could hear but could not discriminate speech sounds. Brain CT and MRI demonstrated small bilateral lesions confined to the Auditory radiations. Magnetoencephalography demonstrated the disappearance of middle latency responses and Auditory-evoked potential studies showed a very small Pa peak. In contrast, a positron emission tomography study demonstrated a marked increase in blood flow in the bilateral Auditory cortex in response to both click and monosyllable stimuli. It is speculated that the ...
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magnetoencephalography and positron emission tomography studies of a patient with Auditory Agnosia caused by bilateral lesions confined to the Auditory radiations
Acta Oto-laryngologica, 2005Co-Authors: Kimitaka Kaga, Mitsuko Shindo, Masako Nakamura, Takahide Kurauchi, Kenji IshiiAbstract:The aim of this study was to investigate Auditory cortex function in the context of Auditory stimuli in a patient with Auditory Agnosia due to bilateral lesions confined to the Auditory radiations. A male patient experienced mild left temporal hemiplegia because of right putaminal hemorrhage at the age of 43 years. Thereafter he recovered completely but hypertension persisted. When he was 53 years old, he suffered left putaminal hemorrhage and went into a coma. After recovering from the coma and right hemiplegia he could hear but could not discriminate speech sounds. Brain CT and MRI demonstrated small bilateral lesions confined to the Auditory radiations. Magnetoencephalography demonstrated the disappearance of middle latency responses and Auditory-evoked potential studies showed a very small Pa peak. In contrast, a positron emission tomography study demonstrated a marked increase in blood flow in the bilateral Auditory cortex in response to both click and monosyllable stimuli. It is speculated that the Auditory cortex receives functional projections from the cochlea via non-specific pathways in the cerebral hemispheres.
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Auditory Agnosia in children after herpes encephalitis
Acta Oto-laryngologica, 2003Co-Authors: Kimitaka Kaga, Makiko Kaga, Fumi Tamai, Mitsuko ShindoAbstract:Four pediatric patients whose bilateral Auditory cortices were damaged by herpes encephalitis at an early age were studied. Their brain CT and MRI scans demonstrated common bilateral lesions of the Auditory cortices. Their Auditory perception was investigated by means of behavioral and objective hearing tests and Auditory perception tests. All four patients showed mild or moderate hearing loss in the behavioral hearing test and normal Auditory brainstem responses but did not manifest total deafness. Moreover, perception tests involving speech, environmental sounds and music demonstrated that most Auditory perception ability had been lost in all patients. On reaching school age, the patients were enrolled in schools for the deaf or special schools for handicapped children.
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long term follow up of Auditory Agnosia as a sequel of herpes encephalitis in a child
Journal of Child Neurology, 2000Co-Authors: Makkiko Kaga, Mitsuko Shindo, Kimitaka KagaAbstract:We report a pediatric patient with Auditory Agnosia as a sequel of herpes encephalitis. His early development was completely normal. He uttered three words at 12 months old. Disease onset was 1 year and 2 months of age. He was discharged from the hospital seemingly with no sequel; however, he could not recover his intelligible words even at age 2 years. He was diagnosed as having Auditory Agnosia caused by bilateral temporal lobe injury. We began to train him at once, individually and intensively. Adult patients with pure Auditory Agnosia followed by two episodes of temporal lobe infarction have impairment in central hearing but not inner language. Therefore, they can communicate by reading and writing. Moreover, impairment in hearing is not always severe and is often transient. However, despite long-term (more than 15 years) energetic education and almost normal intellectual ability (Performance IQ of Wechsler Intelligence Scale for Children-Revised was 91), our patient's language ability was extremely poor. Cerebral plasticity could not work fully on our patient, whose bilateral temporal lobe was severely injured in early childhood. The establishment of a systematic training method in such patients is an urgent objective in this field.
Yoshisato Tanaka - One of the best experts on this subject based on the ideXlab platform.
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neuropathology of Auditory Agnosia following bilateral temporal lobe lesions a case study
Acta Oto-laryngologica, 2000Co-Authors: Kimitaka Kaga, Mitsuko Shindo, Yoshisato Tanaka, Hideyuki HaebaraAbstract:Our patient was first diagnosed with Auditory Agnosia following his second cerebral vascular accident (CVA) in 1975 when he was 37 years old. Comprehensive follow-up examinations of Auditory function were periodically conducted until his sudden death 15 years later. His brain was studied postmortem for neuropathology. Initial pure-tone audiometry revealed moderate sensorineural hearing loss in the right ear and mild sensorineural hearing loss in the left ear. However, repeated pure-tone audiometry revealed that thresholds became progressively poorer over time, bilaterally. Speech audiometry of both ears consistently revealed that the patient was unable to discriminate any monosyllabic words (i.e. speech intelligibility scores were 0%, bilaterally). In general, speech and hearing tests demonstrated that he could not comprehend spoken words, but could comprehend written commands and gestures. Postmortem neuropathological study of the left hemisphere revealed total defect and neuronal loss of the superior temporal gyrus, including Heschl's gyrus, and total gliosis of the medial geniculate body. In the right hemisphere, examination revealed subcortical necrosis, gliosis in the centre of the superior temporal gyrus and partial gliosis of the medial geniculate body. The pathological examination supports clinical results in which the patient's imperception of speech sounds, music and environmental sounds could be caused by progressive degeneration of bilateral medial geniculate bodies.
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Central Auditory Information Processing in Patients with Bilateral Auditory Cortex Lesions
Acta oto-laryngologica. Supplementum, 1997Co-Authors: Kimitaka Kaga, Mitsuko Shindo, Yoshisato TanakaAbstract:Severe Auditory cognitive disorders in 10 patients who had bilateral lesions either to the Auditory cortex and/or Auditory radiations were studied audiologically with special attention to residual hearing. This Auditory cognitive problem is called "Auditory Agnosia or cortical deafness". Our study revealed that Auditory information processing for pure tones, monosyllable discrimination, environmental sound perception, and Auditory comprehension is commonly but differently affected by bilateral lesions of Auditory cortex or Auditory radiation. In summary, these patients can discriminate loudness of pure tones and some environmental sounds but cannot clearly perceive any sounds of monosyllables and sentences. Generally their residual hearing is useful for Auditory awareness and is often enhanced by lip reading.
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developmental process of a case of childhood Auditory Agnosia due to bilateral temporal lesions
The Japan Journal of Logopedics and Phoniatrics, 1992Co-Authors: Mitsuko Shindo, Kimitaka Kaga, Sadayasu Akai, Yoshisato TanakaAbstract:1歳3ヵ月時に単純ヘルペス脳炎による脳内出血にて両側側頭葉損傷をきたし, 聴覚失認を呈した小児に5年間余言語指導を行い, そのコミュニケーションの発達経過と言語学習上の問題点について検討した.聴覚機能の発達については, 経過とともに聴覚の感度はよくなり純音聴力検査で正常閾値を示したが, 聴覚認知の発達はほとんどみられず, 重篤な聴覚認知障害が持続して認められた.発声・発語面では, 意図的な発声が難かしく母音と子音の/pa/の構音のみ習得でき, 発語の習得は困難であった.したがって, 聴覚を介しての音声言語によるコミュニケーションが困難なため, キュード・スピーチを用いて言語指導を行った結果, 6歳までに220語余の語彙と2語文が習得され, 手指言語による日常の簡単なコミュニケーションが可能になった.手指の運動障害がなければ聴覚失認児にとっても, キュード・スピーチは視覚的な言語習得の一方法として有効であると思われる.
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Speech discrimination and lip reading in patients with word deafness or Auditory Agnosia.
Brain and language, 1991Co-Authors: Mitsuko Shindo, Kimitaka Kaga, Yoshisato TanakaAbstract:The purpose of this study was to assess the ability of four patients with word deafness or Auditory Agnosia to discriminate speech by reading lips. The patients were studied using nonsense monosyllables to test for speech discrimination, a lip reading test, the Token Test for Auditory comprehension, and the Aphasia test. Our results show that patients with word deafness or Auditory Agnosia without aphasia can improve speech comprehension by reading lips in combination with listening, as compared with lip reading or listening alone. In conclusion, lip reading was shown to be useful for speech comprehension among these patients.
Thierry Deonna - One of the best experts on this subject based on the ideXlab platform.
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music processing deficits in landau kleffner syndrome four case studies in adulthood
Cortex, 2020Co-Authors: Yohana Leveque, Thierry Deonna, Eliane Rouletperez, Annie Moulin, Lesly Fornoni, Claire Mayordubois, Anne Caclin, Barbara TillmannAbstract:Abstract Verbal-Auditory Agnosia and aphasia are the most prominent symptoms in Landau-Kleffner syndrome (LKS), a childhood epilepsy that can have sustained long-term effects on language processing. The present study provides the first objective investigation of music perception skills in four adult patients with a diagnosis of LKS during childhood, covering the spectrum of severity of the syndrome from mild to severe. Pitch discrimination, short-term memory for melodic, rhythmic and verbal information, as well as emotion recognition in music and speech prosody were assessed with listening tests, and subjective attitude to music with a questionnaire. We observed amusia in 3 out of 4 patients, with elevated pitch discrimination thresholds and poor short-term memory for melody and rhythm. The two patients with the most severe LKS had impairments in music and prosody emotion recognition, but normal perception of emotional intensity of music. Overall, performance in music processing tasks was proportional to the severity of the syndrome. Nonetheless, the four patients reported that they enjoyed music, felt musical emotions, and used music in their daily life. These new data support the hypothesis that, beyond verbal impairments, cerebral networks involved in sound processing and encoding are deeply altered by the epileptic activity in LKS, well after electrophysiological normalization.
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acquired Auditory Agnosia in childhood and normal sleep electroencephalography subsequently diagnosed as landau kleffner syndrome a report of three cases
Developmental Medicine & Child Neurology, 2013Co-Authors: Patrick Van Bogaert, Mary D King, Philippe Paquier, Catherine Wetzburger, Catherine Labasse, Jeanmarie Dubru, Thierry DeonnaAbstract:Aim We report three cases of Landau–Kleffner syndrome (LKS) in children (two females, one male) in whom diagnosis was delayed because the sleep electroencephalography (EEG) was initially normal. Method Case histories including EEG, positron emission tomography findings, and long-term outcome were reviewed. Results Auditory Agnosia occurred between the age of 2 years and 3 years 6 months, after a period of normal language development. Initial awake and sleep EEG, recorded weeks to months after the onset of language regression, during a nap period in two cases and during a full night of sleep in the third case, was normal. Repeat EEG between 2 months and 2 years later showed epileptiform discharges during wakefulness and strongly activated by sleep, with a pattern of continuous spike-waves during slow-wave sleep in two patients. Patients were diagnosed with LKS and treated with various antiepileptic regimens, including corticosteroids. One patient in whom EEG became normal on hydrocortisone is making significant recovery. The other two patients did not exhibit a sustained response to treatment and remained severely impaired. Interpretation Sleep EEG may be normal in the early phase of acquired Auditory Agnosia. EEG should be repeated frequently in individuals in whom a firm clinical diagnosis is made to facilitate early treatment.
Timothy D Griffiths - One of the best experts on this subject based on the ideXlab platform.
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simultaneous Auditory Agnosia systematic description of a new type of Auditory segregation deficit following a right hemisphere lesion
Cortex, 2021Co-Authors: Emma Holmes, Nattawan Utoomprurkporn, Chandrashekar Hoskote, Jason D Warren, Doriseva Bamiou, Timothy D GriffithsAbstract:We investigated Auditory processing in a young patient who experienced a single embolus causing an infarct in the right middle cerebral artery territory. This led to damage to Auditory cortex including planum temporale that spared medial Heschl's gyrus, and included damage to the posterior insula and inferior parietal lobule. She reported chronic difficulties with segregating speech from noise and segregating elements of music. Clinical tests showed no evidence for abnormal cochlear function. Follow-up tests confirmed difficulties with Auditory segregation in her left ear that spanned multiple domains, including words-in-noise and music streaming. Testing with a stochastic figure-ground task-a way of estimating generic acoustic foreground and background segregation-demonstrated that this was also abnormal. This is the first demonstration of an acquired deficit in the segregation of complex acoustic patterns due to cortical damage, which we argue is a causal explanation for the symptomatic deficits in the segregation of speech and music. These symptoms are analogous to the visual symptom of simultaneous Agnosia. Consistent with functional imaging studies on normal listeners, the work implicates non-primary Auditory cortex. Further, the work demonstrates a (partial) lateralisation of the necessary anatomical substrate for segregation that has not been previously highlighted.
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simultaneous Auditory Agnosia systematic description of a new type of Auditory segregation deficit following a right hemisphere lesion
bioRxiv, 2020Co-Authors: Emma Holmes, Nattawan Utoomprurkporn, Chandrashekar Hoskote, Jason D Warren, Doriseva Bamiou, Timothy D GriffithsAbstract:Abstract We investigated Auditory processing in a young patient who experienced a single embolus causing an infarct in the right middle cerebral artery territory. This lead to damage to Auditory cortex including planum temporale that spared medial Heschl’s gyrus, and included damage to the posterior insula and inferior parietal lobule. She first reported difficulty hearing all sounds, which fully recovered within days, but she subsequently reported chronic difficulties with segregating speech from noise and segregating elements of music. Clinical tests showed no evidence for abnormal cochlear function. Follow-up tests confirmed difficulties with Auditory segregation in her left ear that spanned multiple domains, including speech-in-noise and music streaming. Testing with a stochastic figure-ground task—a way of estimating generic acoustic foreground and background segregation—demonstrated that this was also abnormal. This is the first demonstration of an acquired deficit in the segregation of complex acoustic patterns due to cortical damage, which we argue is a causal explanation for the symptomatic deficits in the segregation of speech and music. These symptoms are analogous to the visual symptom of simultaneous Agnosia. Consistent with functional imaging studies on normal listeners, the work implicates non-primary Auditory cortex. Further, the work demonstrates a (partial) lateralisation of the necessary anatomical substrate for segregation that has not been previously highlighted. Highlights Rare case of Auditory Agnosia in a young patient with a right-hemisphere infarct Damage affecting non-primary Auditory cortex, but sparing primary Auditory cortex Generalised Auditory segregation deficit, revealed by Auditory figure-ground task This explains segregation deficits for speech-in-noise and music streaming The deficit affects stimuli presented on the left
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spatial and temporal Auditory processing deficits following right hemisphere infarction a psychophysical study
Brain, 1997Co-Authors: Timothy D Griffiths, Adrian Rees, Caroline Witton, P M Cross, Raad Shakir, Gary G R GreenAbstract:Higher Auditory function in a patient was investigated following a right hemisphere infarction between the middle and posterior cerebral artery territories involving the insula. The patient complained of lack of musical appreciation and a battery of tests confirmed a dissociated receptive musical deficit in the presence of normal appreciation of environmental sounds and speech. The ability to detect continuous changes in sound frequency in the form of sinusoidal frequency modulation was preserved. There was, however, a deficit in the analysis of rapid temporal sequences of notes which could underlie his musical deficit. This case provides further evidence for the existence of amusia as a distinct form of Auditory Agnosia, but does not support the hypothesis that bilateral lesions are required to produce such a deficit. Unexpectedly, the patient was also found to have a deficit in the perception of apparent sound-source movement. We suggest that this deficit is analogous to the visual phenomenon of akinetopsia, and is in accord with PET work suggesting involvement of areas outside primary Auditory cortex in sound movement perception. A possible common deficit in Auditory temporal and spatial 'scene analysis' is discussed.