Action-naming performance in four syndromes of aphasia.

This study examined the influence of two situational contexts on the action-naming performances of 44 aphasic patients: single-word confrontation naming and naming within the context of connected speech. Subjects were evenly distributed among the syndromes of Broca's. Wernicke's, anomic, and conduction aphasia. The two naming tasks employed each comprised the same 18 target verbs. Naming performance was not systematically influenced by the particular naming task in any of the aphasia groups studied. However, for some individuals, particularly in the group of anomic aphasia, there were substantial performance discrepancies between scores obtained on the two different tasks. Correlations between scores on the confrontation-naming and picture-description tasks were highest for the Wernicke's aphasics, followed by the conduction, Broca's, and anomic aphasics. The extent to which action-naming error types could discriminate between the four groups of aphasics was examined. Results obtained in the present study were compared to results obtained in an earlier study on object-naming (S. Williams & G. Canter, 1982), Brain and Language, 17, 92-106). Discussion focuses on implications for the psycholinguistic processes involved in action versus object-naming.

Written spelling deficit of Broca's aphasics.

The purpose of this study was to investigate the nature of the written spelling deficit manifested by Broca's aphasics. Four spelling tests were given to eight Broca's aphasic patients. Analysis of misspelling errors led the investigators to conclude that Broca's aphasics do not spell phonically, but rather adhere exclusively to a visual/orthographic strategy. Possible cognitive deficits underlying the spelling problem are identified. The written spelling deficit is related to other features of the syndrome of Broca's aphasia, and finally, speculations are offered concerning the neurological substrate of written spelling in Broca's aphasic patients.

Neuropsychological analysis of a typewriting disturbance following cerebral damage.

Following a left CVA, a skilled professional typist sustained a disturbance of typing disproportionate to her handwriting disturbance. Typing errors were predominantly of the sequencing type, with spatial errors much less frequent, suggesting that the impairment was based on a relatively early (premotor) stage of processing. Depriving the subject of visual feedback during handwriting greatly increased her error rate. Similarly, interfering with auditory feedback during speech substantially reduced her self-correction of speech errors. These findings suggested that impaired ability to utilize somesthetic information--probably caused by the subject's parietal lobe lesion--may have been the basis of the typing disorder.

Contrasting speech patterns in apraxia of speech and phonemic paraphasia.

This study was designed to determine if perceptual phonological analysis would reveal distinctions between patients with apraxia of speech and patients with phonemic paraphasic speech. Test findings from 10 Broca's aphasics with apraxia of speech were compared to findings from 10 paraphasic speakers (5 conduction and 5 Wernicke's aphasics). Several marked differences were revealed. Predominant locus of errors and relative difficulty of different classes of phonemic segments were significant discriminators. There was a nonsignificant trend for substituted phonemes to be further from target phonetically in the paraphasic patients. In addition, the two groups showed certain consistent differences in the types of errors they produced. Apraxic patients produced many errors of transitionalization, while sequencing errors were more typical of the patients with phonemic paraphasia. The findings are interpreted in relation to a neuropsychological model of speech. It is suggested that phonemic paraphasia represents a breakdown mainly in the retrieval of phonological word patterns, while apraxia of speech is characterized predominantly by a disturbance in encoding phonological patterns into appropriate speech movements.

Comprehension of sentence structure in anomic and conduction aphasia.

Picture-pointing auditory and reading comprehension tests were administered to anomic and conduction aphasics. Subjects responded to active sentences of the present progressive form. The possible errors which a subject could make on these experimental tasks included failure to correctly interpret noun order, number, or lexical meaning. Both groups made significantly more correct responses than error responses. Of their error responses, noun-order errors significantly exceeded number and lexical errors for which no differences were observed. When compared with results previously obtained for agrammatic Broca's aphasics, no differences in the pattern of errors were identified. These results are discussed relative to current theories of syntactic processing and for the mechanisms which account for these syntactic comprehension deficits following aphasia.

A case report of pathological rule-governed syllable intrusion.

A detailed analysis of a unique speech disturbance, marked by the frequent appearance in the speech stream of a meaningless intrusive syllable, is presented. Following a lengthy thoracic surgery, an American English speaking patient began to speak with non-English prosodic patterns, which evolved to a conspicuous intrusion in his speech of the syllable /sis/. This syllable and its variants were attached to words in a manner which conformed to the regular phonological rules in English (for formation of plural, possessive, and third person singular morphemes). The distribution and frequency of the intrusive syllable are described, and possible explanations for the abnormal occurrence of this particular syllable are discussed.

Comprehension of neutral, melodically intoned, and affectively toned sentences by adults with aphasia.

The purpose of this study was to investigate whether there is a notable improvement in the auditory comprehension of adults with aphasia when sentences are melodically intoned or spoken with strong affect, as compared to when the same sentence materials are spoken in a neutral manner. The subjects for this study were six aphasic patients with left-brain damage and two control subjects: one patient with bilateral brain damage and one subject with no history of neurological insult. The subjects responded to a picture identification task where the same sentence stimuli were presented in three conditions: neutral, melodic intonation, and strong affect. There was no significant difference in the left-brain damaged patients' auditory comprehension scores in the three conditions. No improvement of performance was noted for the bilaterally brain-damaged patient, and the nonaphasic subject attained a perfect or near-perfect score in each condition. Results are discussed in terms of the need for future research.

The effect of redundant cues on comprehension of spoken messages by aphasic adults.

Aphasic adults with severe auditory comprehension impairment responded to redundant and nonredundant spoken and/or gestured messages by pointing to pictures. Messages of two types (pantomime and emblem) were presented under four conditions (spoken message alone, spoken message repeated, gestured message alone, and spoken message plus redundant gesture). Though spoken messages repeated and spoken messages with gestures were comprehended significantly more often than gestures alone, neither of these stimulus conditions was reliably superior to spoken messages alone. This finding casts doubt on the clinical strategy of supplementing spoken messages with redundant gestures when auditory comprehension is severely impaired, and raises questions about the ability of severely aphasic individuals to utilize semantically redundant message content. Pantomimes were consistently comprehended more frequently than emblems, regardless of stimulus condition. This finding was attributed to a depictability factor: the pictures associated with pantomimes were relatively direct representations of item content, while those associated with emblems were necessarily less direct representations. For this group of subjects, whose range of comprehension deficit was deliberately restricted, neither auditory nor reading comprehension at the single-word level was found to correlate with comprehension of symbolic gestures.

An investigation of Luria's hypothesis on prompting in aphasic naming disturbances.

This study investigated Luria's hypothesis that aphasic subgroups would respond differentially to phonemic prompts. Responsiveness to initial-sound cues was examined in 40 aphasics--10 Broca's, conduction, Wernicke's, and anomic aphasics who had naming difficulties. Results, with the exception of the anomic aphasic group, supported Luria's predictions. Broca's aphasics were responsive to phonemic cueing, while Wernicke's aphasics were not. Conduction aphasics tended to respond in a fashion similar to the Wernicke's group. The relationship of cueing responsiveness to underlying naming mechanisms is discussed.

Disturbances of the temporal organization of speech following bilateral thalamic surgery in a patient with Parkinson's disease.

This report summarizes a detailed analysis of the speech of a 45-yr-old man who had become dysarthric following bilateral thalamic surgery for the relief of symptoms of Parkinson's disease. His speech was characterized by a rapid rate and a mild-to-moderate articulatory deficit. Intelligibility was markedly reduced. The rapid rate was found to be the result of decreased syllable durations rather than to changes in pause or phrase patterns. Decreased syllable durations resulted from abnormal shortening of vowels. Consonant releases were found to be prolonged. This distorted temporal relationship among speech segments was considered to be an important factor in the patient's poor intelligibility and partially explained why uniform electronic expansion of his speech resulted in only negligible increase in intelligibility. It is hypothesized that this speech disturbance results from the interaction of central "metronomic" abnormality with a peripheral neuromotor articulatory impairment.

Effects of personally relevant language materials on the performance of severely aphasic individuals.

The purpose of this study was to determine whether or not severely aphasic adults perform better with personally relevant language materials than with otherwise similar nonpersonal language materials. The subjects for this study were 24 severely aphasic individuals. Subjects responded to personally relevant and nonpersonal materials in four language tasks: auditory comprehension, speech repetition, naming, and reading comprehension. Subjects showed significantly better performance on personally relevant items than on nonpersonal items. This was true for each of the four tasks.

Postlingual deaf speech and the role of audition in speech production: comments on Waldstein's paper [R.S. Waldstein, J. Acoust. Soc. Am. 88, 2099-2114 (1990)].

Using acoustic analysis techniques, Waldstein [J. Acoust. Soc. Am. 88, 2099-2114 (1990] reported abnormal speech findings in postlingual deaf speakers. She interpreted her findings to suggest that auditory feedback is important in motor speech control. However, it is argued here that Waldstein's interpretation may be unwarranted without addressing the possibility of neurologic deficits (e.g., dysarthria) as confounding (or even primary) causes of the abnormal speech in her subjects.

Idiomatic versus literal interpretations of ditropically ambiguous sentences.

"Ditropically" ambiguous sentences (each having both a literal and an idiomatic interpretation) were prepared for listener's discrimination judgments, and for silent readers' rankings on an "idiomaticity" scale. Listeners were unable to discriminate the literal from the idiomatic versions when presented with randomized single sentences excised from paragraph contexts. There was a bias toward interpreting the sentences as idioms, which correlated with rankings of each sentence for its likelihood of idiomatic use. Listeners were easily able to identify the literal and the idiomatic versions of the same ditropic sentences presented in pairs or singularly, when speakers sought purposively to convey the contrasting meanings.

Variables influencing phonemic discrimination performance in normal and learning-disabled children.

Twenty-five learning-disabled and 25 normal first-grade-age children took a phonemic discrimination test that manipulated word-pairs systematically according to degree of phonetic difference, position of phoneme contrast, and lexical familiarity. Results indicated that (1) the significantly lower performance of the learning-disabled to children as a group was due to the impaired performance by a small subgroup, (2) all three stimulus variables had significant effects on performance, (3) all combinations of stimulus variables interacted significantly, and (4) discrimination performance did not correlate with measures of receptive vocabulary or reading achievement for either group.

Perception of intraphonemic differences by phoneticians, musicians, and inexperienced listeners.

Several studies have shown that extensive training with synthetic speech sounds can result in substantial improvements in listeners' perception of intraphonemic differences. The purpose of the present study was to investigate the effects of listening experience on the perception of intraphonemic differences in the absence of specific training with the synthetic speech sounds being tested. Phonetically trained listeners, musicians, and untrained listeners were tested on a two-choice identification task, a three-choice identification task, and an ABX discrimination task using a synthetic [bi]-[phi] continuum and a synthetic [wei]-[rei] continuum. The three-choice identification task included the identification of stimuli with an "indefinite" or "ambiguous" quality in addition to clear instances of the opposing phonetic categories. Results included: (1) All three subject groups showed some ability to identify ambiguous stimuli; (2) phonetically trained listeners were better at identifying ambiguous stimuli than musicians and untrained listeners; (3) phonetically trained listeners performed better on the discrimination task than musicians and untrained listeners; (4) musicians and untrained listeners did not differ on any of the listening tasks; and (5) participation by the inexperienced listeners in a 10-week introductory phonetics course did not result in improvements in either the three-choice identification task or the discrimination task.