Rapid recovery from aphasia: a detailed language analysis

The paper presents a daily analysis of the language recovery of a patient who was globally aphasic at the time of her first observation and who had recovered language, as measured by the Western Aphasia Battery, at the time of her discharge 14 days later. The paper emphasizes the relatively regular growth of normal syntactic, lexical, and pragmatic features coupled with similar regular decreases in aphasic features. Observations of both phenomena are necessary to describe language recovery.     

Effects of speech and language treatment on recovery from aphasia

Language recovery in aphasic patients who received one of three types of speech and language treatment was compared with that in aphasic patients who received no treatment. One hundred aphasic patients were followed from 2 to 4 weeks postonset for 1 year or until recovery, using a standardized test battery administered at systematic intervals. Both treatment methods provided by trained speech-language pathologists were efficacious, while the method provided by trained nonprofessionals approached statistical significance. Small group size prevented resolution of the question of whether one type of treatment was superior to another.     

The signing brain: the neurobiology of sign language

Most of our knowledge about the neurobiological bases of language comes from studies of spoken languages. By studying signed languages, we can determine whether what we have learnt so far is characteristic of language per se or whether it is specific to languages that are spoken and heard. Overwhelmingly, lesion and neuroimaging studies indicate that the neural systems supporting signed and spoken language are very similar: both involve a predominantly left-lateralised perisylvian network. Recent studies have also highlighted processing differences between languages in these different modalities. These studies provide rich insights into language and communication processes in deaf and hearing people.     

The neural organization of language: evidence from sign language aphasia

To what extent is the neural organization of language dependent on factors specific to the modalities in which language is perceived and through which it is produced? That is, is the left-hemisphere dominance for language a function of a linguistic specialization or a function of some domain-general specialization(s), such as temporal processing or motor planning? Investigations of the neurobiology of signed language can help answer these questions. As with spoken languages, signed languages of the deaf display complex grammatical structure but are perceived and produced via radically different modalities. Thus, by mapping out the neurological similarities and differences between signed and spoken language, it is possible to identify modality-specific contributions to brain organization for language. Research to date has shown a significant degree of similarity in the neurobiology of signed and spoken languages, suggesting that the neural organization of language is largely modality-independent.     

Analytical competence and language impairment in aphasia

Matched groups of Broca's and Wernicke's aphasics, brain-damaged patients without aphasia and chronic schizophrenics were tested in a nonverbal matching task where the subject had to indicate which of two pictures was more closely linked to a clue picture. Eight additional verbal and nonverbal reference tasks were administered. Both aphasic groups performed worse than brain-damaged controls when the identification of individual attributes or actions shared by clue and referent was required, but were unimpaired when the two had a set of referential-situational associations in common. Factor analyses resulted for both groups in two factors, one of which represents general Language Impairment. For the Broca's aphasics this factor was closely related to general organic deficit as measured by the Trail Making Test; for the Wernicke's aphasics it was associated with tasks which might be considered illustrative of analytical competence in isolating and comparing individual features of objects or concepts.     

Cerebral dominance in aphasia recovery.

This investigation studied the patterns of ear preference of a group of 25 aphasic adults through the administration of two verbal dichotic tests and retests over a 2-month interval of time. These dichotic tests were a Dichotic Digits Test (DDT) and a Dichotic Animal Names Test (DANT). Schuell's short test of aphasia was given twice over this interval to assess language recovery. Results indicated that as aphasics improve in language, cerebral dominance becomes more firmly established in the right cerebral hemisphere. The data in this study tend to support a dominance shift hypothesis in the recovery of language after aphasia.     

Aphasia in left-handers. Comparison of aphasia profiles and language recovery in non-right-handed and matched right-handed patients.

The present retrospective analysis reports two studies. In Study 1, clinical aspects of aphasia are compared in right-handed (RH) and non-right-handed (NRH) patients; in Study 2, recovery from aphasia is compared in RH and NRH aphasic patients with a minimum of 5 months of daily language rehabilitation. From a continuous series of 1200 brain-damaged subjects, 24 NRH patients with a vascular lesion documented by computerized tomography were selected. In 19 cases the lesion was in the left hemisphere and in 5 cases in the right hemisphere. For 14 NRH patients, a RH subject with similar lesion, matched for age, education, length of illness, etiology (ischemic vs. hemorrhagic), and, when possible, sex was found. Presence and type of aphasia were compared in the two patients of the same pair and were found similar except for Pair 14; the RH subject had global aphasia and the NRH had conduction-like aphasia. Fifteen NRH patients were rehabilitated and reexamined at least 5 months after the first examination. Recovery of the 12 patients with a left-hemisphere lesion was compared with recovery of a group of RH subjects and no significant differences were found. Recovery of the three patients with right-hemisphere lesions is described. It is concluded that differences in type of aphasia and recovery between RHs and NRHs have been overemphasized in the past and must be reconsidered.     

Some aspects of language comprehension in anterior aphasia

The competency of language comprehension was evaluated in three groups: anterior aphasics, posterior aphasics, and normal control subjects. Test material was divided into two sentence groups (Fill in the Blank and True/False) emphasizing either (1) semantic, “real world,” identity words or (2) syntactic, relational words, and one paragraph interpretation task. Matching auditory and visual (written) presentations were given. The control subjects performed almost flawlessly but many errors were made by each aphasia group. Qualitative study revealed a marked difference in the comprehension problem of the two groups. The anterior aphasic group performed well on semantically weighted sentences but made errors on syntactically weighted material, regardless of mode of presentation. In contrast, the posterior aphasics made almost the same number of errors on both types of material, regardless of mode of presentation. These findings support the concept of defective language comprehension in anterior aphasia and further suggest that the defect centers on the syntactical structures which are also poorly handled in expressive output.     

A real-time approach to spoken language processing in aphasia

The study is based on an on-line investigation of spoken language comprehension processes in 25 French-speaking aphasics using a syllable-monitoring task. Nonsense syllables were presented in three different conditions: context-free (embedded in strings of nonsense syllables), lexical context (where the target nonsense syllable is the initial, medial, or final syllable of real three-syllable words), and sentence context. This study builds on an earlier one that explored the relationship between the acoustic-phonetic, lexical, and sentential levels of spoken language processing in French-speaking normals and gave evidence of top-down lexical and sentential influence on syllable recognition. In the present study, aphasic patients from various diagnostic categories were classified as high (N = 13) or low (N = 12) comprehenders. The results show that low comprehending aphasics make no use of sentence information in the syllable-recognition task. As for top-down effect at the single word level that is observed in normal listeners. However, a subgroup analysis shows that the Broca's are the only high comprehending aphasics who perform in the same way as normal listeners; this sets them apart from the anomics and conduction aphasics.     

A proposed regional hierarchy in recovery of post-stroke aphasia

Activation studies in patients with aphasia due to stroke or tumours in the dominant hemisphere have revealed effects of disinhibition in ipsilateral perilesional and in contralateral homotopic cortical regions, referred to as collateral and transcallosal disinhibition. These findings were supported by studies with selective disturbance of cortical areas by repetitive transcranial magnetic stimulation (rTMS) in healthy volunteers and in patients with focal brain lesions. Both, collateral as well as transcallosal disinhibition might be relevant for the compensation of lesions within a functional network. From these data a hierarchical organization of recovery of aphasia after stroke and of compensation of language defects due to brain tumours can be deduced, by which the reactivation of undamaged network areas of the ipsilateral hemisphere usually lead to better outcome than the involvement of homotopic contra-lateral regions. rTMS can be used to identify areas relevant for speech production and might play a role in treatment strategies targeted at modulating the activity of contralateral homotopic areas of the functional network which might interfere with language recovery.     

Influence of aging on recovery from aphasia in polyglots

We analyzed patterns of recovery, according to the rules of Pitres [1895, Revue de Medecine (Paris), 15, 873–899] and Ribot (1881, Les Maladies de la Memoire, Paris: Libraire Germer Baillere et Cie, pp. 146–147), in polyglot aphasics divided into subgroups by age. The rule of Ribot did not apply predictably for any age group. Pitres' rule clearly applied, but only for the nonelderly groups. Aging and its concomitant deterioration of recent memory seem to influence patterns of recovery from aphasia in polyglots.     

Dichotic listening in the recovery of aphasia after stroke

Three different dichotic listening tests were given to a group of aphasic patients at various stages of the recovery process. Results were different for each test and in the course of time fluent aphasics demonstrated a tendency to increase right ear preference while nonfluent aphasics showed an increase of left ear preference in the test of dichotic words. The importance of these findings to the understanding of recovery of function is discussed in terms of the role played by the right hemisphere.     

Controversies about CP: a comparison of language acquisition and language impairments in Broca's aphasia

In both language acquisition research and the study of language impairments in Broca's aphasia there is an ongoing debate whether or not phrase-structure representations contain the Complementizer Phrase (CP) layer. To shed some light on this debate, I will provide data on German child language and on German agrammatic Broca's aphasia. Analyses of subordinate clauses, wh-questions, and verb placement indicate that early child grammars do not generate the CP layer yet, whereas the ability to project the CP layer is retained in agrammatism.     

Recovery from aphasia: Spontaneous speech versus language comprehension

Seventy-four aphasic patients, subdivided into four groups (fluent, mixed, nonfluent, and severely nonfluent), were tested three times in the course of 1 year to assess recovery of spontaneous speech and sentence comprehension. Although 12 of the 28 spontaneous speech variables employed showed significant time changes, some of these changes indicated improvement and others deterioration. There was no overall clinical improvement in spontaneous speech in any group. On the sentence comprehension tests, however, all four groups did show considerable, significant improvement. There were no qualitative or quantitative differences among the groups in the course of recovery, despite the fact that the groups differed in the severity of aphasia as well as on the fluency dimension. In certain patients there was also some improvement in spontaneous speech, but this did not in most cases correlate with an improvement in either fluency or sentence comprehension. Possible reasons why receptive abilities improved more than expressive abilities are discussed.     

The italian determiner system in normal acquisition, specific language impairment, and childhood aphasia

The paper presents a comparison of the development of the Italian determiner system in three different populations: normally developing children, a child recovering from childhood aphasia from the age of 3 years, 9 months, and 11 specific language impairment (SLI) children. Data from Italian normal children provide evidence for the hypothesis (1) that no prefunctional stage exists as far as the determiner system is concerned and (2) that the syntactic properties of determiners play an essential triggering role early on. The analysis of the determiner system in the aphasic child has a double interest. On the one hand, it may help to shed light on some of the intriguing questions concerning this type of disorder; on the other, it may be relevant for the discussion of the notion of agrammatism. Results of the morphosyntactic analysis reveal that, apart from timing differences, recovery from childhood aphasia shares important features with normal development. Differently from mean length of utterance (MLU)-matched normal controls and the aphasic child, SLI children omit determiners significantly more often than almost any other functional category or free morpheme. We will argue that the reasons for the SLI children's atypical behavior have to be sought in the nonaccessibility to or in the misappreciation of one fundamental syntactic property of determiners: their role as elements that assign argumenthood to nominal expressions (Szabolcsi, 1987; Longobardi, 1994).     

Effect of socioeconomic status on aphasia severity and recovery

Low levels of educational attainment and low socioeconomic status have been significantly linked to poor health and increased incidence of disease, including Alzheimer's disease and diseases of the cardiovascular, pulmonary, renal, and gastrointestinal systems. Our goal in the present study was to determine the degree to which educational level and socioeconomic status influence initial severity of aphasia and subsequent recovery. We evaluated the records of 39 persons with aphasia twice: at about 4 months and 103 months postonset. We found early severity of aphasia to be significantly greater for subjects in the lower educational and occupational groups. However, rate of recovery (the slope of the recovery curve) was the same regardless of educational or occupational status.