PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Aphasia, Conduction”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Differences between conduction aphasia and Wernicke's aphasia.

Conduction aphasia and Wernike's aphasia have been differentiated by the degree of auditory language comprehension. We quantitatively compared the speech sound errors of two conduction aphasia patients and three Wernicke's aphasia patients on various language modality tests. All of the patients were Japanese. The two conduction aphasia patients had "conduites d'approche" errors and phonological paraphasia. The patient with mild Wernicke's aphasia made various errors. In the patient with severe Wernicke's aphasia, neologism was observed. Phonological paraphasia in the two conduction aphasia patients seemed to occur when the examinee searched for the target word. They made more errors in vowels than in consonants of target words on the naming and repetition tests. They seemed to search the target word by the correct consonant phoneme and incorrect vocalic phoneme in the table of the Japanese alphabet. The Wernicke's aphasia patients who had severe impairment of auditory comprehension, made more errors in consonants than in vowels of target words. In conclusion, utterance of conduction aphasia and that of Wernicke's aphasia are qualitatively distinct.

Aged↗

A functional magnetic resonance imaging study of the role of left posterior superior temporal gyrus in speech production: implications for the explanation of conduction aphasia.

Conduction aphasia, characterized by good auditory comprehension and fluent but disordered speech production, is classically viewed as a disconnection syndrome. We review recent evidence which suggests that at least one form of conduction aphasia results from damage to cortical fields in the left posterior superior temporal gyrus which participate not only in speech perception, but also in phonemic aspects of speech production. As a test of this hypothesis, we carried out a 4T functional magnetic resonance imaging study in which subjects named visually presented objects sub-vocally. Group-based analyses showed that a majority of participants showed activation in two regions on the dorsal portion of the left posterior superior temporal gyrus.

Adult↗

Primary progressive aphasia presenting as conduction aphasia.

We report a case of a woman with primary progressive aphasia (PPA) who presented with conduction aphasia. A 60-year-old, right-handed, Japanese female suffering from progressive aphasia had difficulty in repeating words and phrases. She displayed phonemic paraphasias but had preserved comprehension and had no cognitive or behavior disorder for more than 6 years after the onset of the condition. She was able to continue to work successfully and to perform all her normal daily activities. T1-weighted magnetic resonance imaging revealed minute dilatation of the left inferior horn and sulci in the left hemisphere, and positron emission tomography revealed mild hypometabolism in the left supramarginal gyrus and its surrounding areas. Therefore, she was diagnosed as suffering from PPA presenting as conduction aphasia. We believe that the progressive conduction aphasia of the patient belongs to one of the fluent forms of PPA, and the ability to continue normal work along with the clinical portrayal of preserved memory and cognition skills may be features of a form of PPA presenting as conduction aphasia.

Aphasia, Conduction↗

Disconnection and cerebral metabolism. The case of conduction aphasia.

Ten patients with conduction aphasia were studied with computed tomography and 18-F-fluorodeoxyglucose positron emission tomography to examine glucose metabolism. Computed tomographic results identified a postrolandic structural locus for conduction aphasia. All patients demonstrated resting glucose hypometabolism throughout the parietal and temporal regions, and half of the patients also demonstrated reduced metabolic rates in the posterior, inferior, frontal (Broca's) regions. These data suggest that disconnection between posterior and anterior language areas may not be the best anatomical explanation for conduction aphasia.

Adult↗

Supra- and infrasylvian conduction aphasia.

Fifteen cases of conduction aphasia which were tested with the Aachen Aphasia Test (AAT), are presented. The CT lesion data were transformed to a standard 3D-reference brain referring to the ACPC line. According to the lesion profiles a group of 6 patients had pure suprasylvian lesions, a group of 4 patients had pure infrasylvian lesions, and a group of 5 patients had lesions in both supra- and infrasylvian regions. Suprasylvian conduction aphasics are superior to infrasylvian conduction aphasics in the token test and in repetition tasks. Infrasylvian conduction aphasics use more stereotypes in spontaneous speech than suprasylvian conduction aphasics. Conduction aphasics with both lesion sites perform less well in tests of naming, writing, and comprehension than the pure types. Thus conduction aphasia is a heterogeneous syndrome anatomically and linguistically.

Adult↗

[Conduction aphasia and phonemic disorder].

Conduction aphasia is usually described as a repetition impairment. Semiology or pathophysiology cannot be explained with this definition. We report a single case particularly demonstrative. The patient showed spontaneous speech, denomination, repetition and reading impairments. Main errors were phonemic paraphasia. No arthric disorder nor comprehension impairment was observed. Damage of supramarginalis gyrus and Wernicke's area was found. A cognitive analysis suggested that the phonological buffer and the working memory were impaired. Implication for rehabilitation, which included segmentation and semantisation associated to phonological training, is discussed. The course of the conduction aphasia was good and the patient was able to work again.

Aphasia, Conduction↗

Phonological transformations in conduction aphasia.

Different explanations and subtypes of conduction aphasia are analyzed. Characteristics of literal paraphasias in parietal-insular conduction aphasia are discussed, emphasizing that paraphasias in conduction aphasia are articulatory-based (articulatory literal paraphasias) and due mainly to phoneme substitutions and phoneme deletions; they result basically in switches in phoneme manner and place of articulation. Similarities between errors in ideomotor apraxia and conduction aphasia language deficits are presented. It is proposed that language deviations (in oral as in written language) in conduction aphasia can be understood as a segmentary apraxia of speech.

Aphasia, Wernicke↗

Atypical conduction aphasia. A disconnection syndrome.

Conduction aphasia was originally proposed to result from separation of the posterior language comprehension area and the anterior motor speech area of the left hemisphere. The arcuate fasciculus has been the most frequently suggested site of such a disconnection, but the syndrome has been reported in cases in which the abnormality involved the dominant Wernicke's area. This challenges the arcuate fasciculus theory, and it has been suggested that a cortical lesion, not a disconnection, is the crucial factor. Three new cases in which the lesion does not lie in the arcuate fasciculus are reported, two in left-handed patients with left temporoparietal lesions and one in a right-handed patient with a right temporoparietal infarct, a "crossed" aphasia. While atypical, these cases offer evidence that disconnection of the circuit linking language comprehension to motor speech output, not damage to a specific cortical region, underlies the syndrome of conduction aphasia.

Adult↗

Conduction aphasia and arcuate fasciculus.

Three patients are presented who developed conduction aphasia after a small infarction almost exclusively confined to the arcuate fasciculus. All of them were diagnosed as conduction aphasia within a week after the stroke and showed a rapid amelioration. On the basis of the 3 patients and conduction aphasics in the literature, the relation between conduction aphasia and the arcuate fasciculus is discussed.

Aged↗

'Inner speech' in conduction aphasia.

It has been suggested by Kurt Goldstein, MD, that conduction aphasia is a disturbance of "inner speech." We tested this hypothesis in five patients who had conduction aphasia with similar speech disturbances. The patients were presented with pictures and were required to perform, without overt vocalization, comparisons of word length and homophonic and rhyming matches. Four patients successfully performed such judgments on words they could not vocalize, but one patient could not. These findings suggest that the hypothesis may have been correct for only a subgroup of conduction aphasics. The findings also provide evidence for heterogeneity within the class of conduction aphasia.

Aged↗

Conduction aphasia and the arcuate fasciculus: A reexamination of the Wernicke-Geschwind model.

Wernicke, and later Geschwind, posited that the critical lesion in conduction aphasia is in the dominant hemisphere's arcuate fasciculus. This white matter pathway was thought to connect the anterior language production areas with the posterior language areas that contain auditory memories of words (a phonological lexicon). Alternatively, conduction aphasia might be induced by cortical dysfunction, which impairs the phonological output lexicon. We observed an epileptic patient who, during cortical stimulation of her posterior superior temporal gyrus, demonstrated frequent phonemic paraphasias, decreased repetition of words, and yet had intact semantic knowledge, a pattern consistent with conduction aphasia. These findings suggest that cortical dysfunction alone may induce conduction aphasia.

Aphasia, Conduction↗

Speech timing in apraxia of speech versus conduction aphasia.

This study examined temporal parameters of speech in subjects with apraxia of speech, conduction aphasia, and normal speech. They were asked to repeat target words in a carrier phrase 10 times. Acoustic analyses involved measurement of stop gap duration, voice onset time, vowel nucleus duration, and consonant-vowel (CV) duration. Speakers with apraxia of speech had longer and more variable stop gap, vowel, and CV durations than did subjects with aphasia or normal speech. Speakers with conduction aphasia had longer vowel durations and CV durations than subjects with normal speech. Also, subjects with apraxia of speech showed greater token-to-token variability than the other subject groups. The variability shown by subjects with apraxia of speech was significantly correlated with perceptual judgments of their speech. The significance of these results is discussed in the context of motoric and phonological explanations for apraxia of speech and conduction aphasia.

Adult↗

[A case of conduction aphasia due to small infarction in the left parietal lobe].

This is a report on the patient with conduction aphAsia due to small infarction in the left parietal lobe. The patient is a right-handed man aged 74, who developed a speech disorder and mild paralysis of the right hand on November 13. 1996. A CT scan showed a small low-density in the supramarginal gyrus of the left parietal lobe. Standard Language Test of aphasia (SLTA) conducted at five days after admission to the hospital showed preserved auditory comprehension and phonemic para-aphasia symptoms with respect to volitional speech, naming, reading aloud and repetition. Frequent self-correction was also observed while repetition was not remarkably impaired. A test at three months after the onset revealed generally fluent speech, while there still remained occasional phonemic para-aphasia and self-correction for the speech disruption. Three years and four months later, most of the aphasic syndromes disappeared, although the patient claimed he still had difficulty in speaking. This case suggests that conduction aphasia can be caused by a lesion, though small, located in arcuate fibers of the cerebrum. The characteristics are phonemic para-aphasia with respect to general speech functions as well as self-correction toward target words. The indicated that lesions in the pathway connecting Broca's area and Wernicke's area causes difficulties in selecting accurate phonemes due to a malfunctioning interface between the two areas.

Aged↗

Interruption of phonological coding in conduction aphasia.

A case study of conduction aphasia, investigating single word repetition, phonological coding, and short-term memory, is reported. Evidence from intact adults suggests that repetition can occur through either a lexical route or a direct auditory-articulatory link. For this conduction aphasic, E.A., the direct link was impaired, although the lexical route could be used to produce accurate single word repetition. Several experiments demonstrated a significant impairment in the generation and maintenance of an abstract phonological code. The consequences of a disruption of phonological coding on speech perception and on verbal short-term memory are discussed.

Aphasia↗

Conduction aphasia, syntactic alexia, and the anatomy of syntactic comprehension.

Syntactic alexia is the inability to comprehend graphically presented sentences when the meaning depends on syntax. Although previously described in association with Broca's aphasia and attributed solely to the frontal lobe portion of the lesions, syntactic alexia has not been reported to accompany conduction aphasia. We studied three patients who had conduction aphasia from temporoparietal lesions and syntactic alexia. None of them had lesions in Broca's area. Broca's aphasics and our patients with conduction aphasia have a syntactic comprehension disturbance. Since Broca's aphasics and our patients have lesions that may extend into the supramarginal gyrus, we postulate that this area may be critical for comprehending syntax.

Aphasia↗