1/74. "Pure word deafness": implications for assessment and management in communication disorder--a report of two cases. In "pure word deafness" after acquired brain injury, the auditory comprehension of words is much more impaired than other aspects of communication or cognition. Two cases are presented, one early and one late presentation. The key to diagnosis of communication disorders is to remember to assess all six basic aspects of language function and to be vigilant for coexisting diagnoses that can complicate such assessment (especially psychiatric diagnoses). rehabilitation management of impaired communication should emphasize the teaching of specific coping mechanisms to the patient and to all others who are involved. ( info) |
2/74. Developmental prosopagnosia with normal configural processing. The configural processing hypothesis proposes that prosopagnosia results from a domain-general impairment in configural processing, and so predicted that all prosopagnosics would have impaired configural processing. In order to test this prediction, tests of face recognition and configural processing were presented to a developmental prosopagnosic. He was severely impaired in face recognition, but his normal performance on three tests of configural processing disconfirmed the configural processing hypothesis. Additional tests of low-level vision and object recognition found no evidence of impairments with material other than faces. The pattern of spared and impaired face recognition indicates that this case of developmental prosopagnosia is caused by a domain-specific inability to match novel views of faces with previously derived representations. ( info) |
3/74. Obsession of hearing music: from the viewpoint of Morita theory. We present two typical cases among five Japanese students who have complained of hearing music. They were found among 638 student case reports during 4 years at the mental health service center of a preparatory school. We diagnosed the complaint of hearing music as a symptom of obsession. Morita therapy was an effective treatment for this symptom. We discuss the characteristics of the symptom as an obsession and the therapy in the light of Morita theory. ( info) |
4/74. Musical instrument naming impairments: the crucial exception to the living/nonliving dichotomy in category-specific agnosia. In category-specific agnosia (CSA) patients typically have more trouble naming animals, fruits, and vegetables than tools, furniture, and articles of clothing. A crucial exception to this living vs nonliving rule involves the category of musical instruments. patients with problems naming living objects often repeatedly fail to name musical instruments. In CSA it is crucial to equate living and nonliving object lists on object name frequency, complexity, and familiarity. The present study shows, however, that even the most rigorously controlled object lists can lead to erroneous conclusions if nonliving stimuli contain an overrepresentation of musical instruments. Naming capabilities of a herpes encephalitis patient were assessed using matched lists of living and nonliving objects and showed no indication of category-specific deficits. When exemplars were separated into biological objects, musical instruments and man-made artifacts, strong category-specificity emerged: artifact naming was flawless whereas musical instrument and biological object naming were both severely impaired. It is concluded that CSA is a veridical phenomenon but that our understanding of CSA is limited by adhering to the spurious living/nonliving distinction. ( info) |
5/74. Perception of dynamic acoustic patterns by an individual with unilateral verbal auditory agnosia. Previous studies have found that subjects diagnosed with verbal auditory agnosia (VAA) from bilateral brain lesions may experience difficulties at the prephonemic level of acoustic processing. In this case study, we administered a series of speech and nonspeech discrimination tests to an individual with unilateral VAA as a result of left-temporal-lobe damage. The results indicated that the subject's ability to perceive steady-state acoustic stimuli was relatively intact but his ability to perceive dynamic stimuli was drastically reduced. We conclude that this particular aspect of acoustic processing may be a major contributing factor that disables speech perception in subjects with unilateral VAA. ( info) |
6/74. Modularity of music: evidence from a case of pure amusia. A case of pure amusia in a 20 year old left handed non-professional musician is reported. The patient showed an impairment of music abilities in the presence of normal processing of speech and environmental sounds. Furthermore, whereas recognition and production of melodic sequences were grossly disturbed, both the recognition and production of rhythm patterns were preserved. This selective breakdown pattern was produced by a focal lesion in the left superior temporal gyrus. This case thus suggests that not only linguistic and musical skills, but also melodic and rhythmic processing are independent of each other. This functional dissociation in the musical domain supports the hypothesis that music components have a modular organisation. Furthermore, there is the suggestion that amusia may be produced by a lesion located strictly in one hemisphere and that the superior temporal gyrus plays a crucial part in melodic processing. ( info) |
7/74. Disorder in sequential speech perception: a case study on pure word deafness. We described disorders of a patient which were uniquely restricted to speech perception of syllable sequences after brain damage. The results of series of experiments using syllable sequences showed "negative recency effect," in which the subject's repetition performance at the latter syllable position was remarkably poor. Experimental analyses suggested that the "negative recency effect" could be due to dual factors: the lower rate of processing of speech sounds and the memory load of holding processes of preceding syllables imposed on the succeeding phonological processing. The results also suggested that the holding processes which imposed the memory load on the succeeding auditory phonological coding processing were modality nonspecific. ( info) |
8/74. Generalized auditory agnosia with spared music recognition in a left-hander. Analysis of a case with a right temporal stroke. After a right temporoparietal stroke, a left-handed man lost the ability to understand speech and environmental sounds but developed greater appreciation for music. The patient had preserved reading and writing but poor verbal comprehension. Slower speech, single syllable words, and minimal written cues greatly facilitated his verbal comprehension. On identifying environmental sounds, he made predominant acoustic errors. Although he failed to name melodies, he could match, describe, and sing them. The patient had normal hearing except for presbyacusis, right-ear dominance for phonemes, and normal discrimination of basic psychoacoustic features and rhythm. Further testing disclosed difficulty distinguishing tone sequences and discriminating two clicks and short-versus-long tones, particularly in the left ear. Together, these findings suggest impairment in a direct route for temporal analysis and auditory word forms in his right hemisphere to Wernicke's area in his left hemisphere. The findings further suggest a separate and possibly rhythm-based mechanism for music recognition. ( info) |
9/74. Are text and tune of familiar songs separable by brain damage? The recognition of text and tune in songs was examined in a music-agnosic patient and five matched controls. Listeners had to focus on one component of the song at a time (text or music) and had to decide whether the component was familiar or unfamiliar. Songs were either matched (i.e., an original familiar or an original unfamiliar song) or mismatched (a combination of a familiar component with an unfamiliar one). Normal listeners displayed response patterns that are congruent with those obtained previously in different experimental settings and which showed that text and tune are difficult to separate. Data collected in the patient, however, suggest some independence between text and music in songs. Moreover, the usual asymmetry in favor of text was much reduced when later verses were used. overall, the results are interpreted as revealing strong association, not integration, between the musical and the verbal component of familiar songs. ( info) |
10/74. Short-term memory impairment and unilateral dichotic listening extinction in a child with landau-kleffner syndrome: auditory or phonological disorder? The neuropsychological profile of a child with a landau-kleffner syndrome is presented here. The observed cognitive difficulties included verbal short-term memory and seemed partially compensated for when the experimental assessments bypassed the auditory channel. This case study is especially challenging since the child, whose phonological skills were quite efficient and who exhibited a dichotic listening unilateral extinction, had developed average reading and spelling abilities. The fact that B.E.'s performance on memory tasks was quite poor when the stimuli were presented auditorily and more efficient when the stimuli were presented visually, strongly suggests that the observed memory impairment was due to a deficit at the level of cortical auditory processing. B.E.'s phonological skills were efficient, suggesting a neuropsychological dissociation between phonological ability and auditory processing. The fact that B.E. dramatically recovered language and easily acquired reading and spelling accounts for the hypothesis that compensatory strategies allowed him to develop phonological skills from predominantly visual input. ( info) |