Discourse studies in neurologically impaired populations: a quest for action

Neuropragmatics: A scientometric review

Neuropragmatics investigates brain functions and neural activities responsible for pragmatic language abilities, often impaired in disorders such as hemisphere damage, autism, schizophrenia, and neurodegenerative disorders. This study examined the development of neuropragmatics and existing neuroimaging evidence using bibliometric and scientometric indicators, analyzing 4,247 documents published between 1967 and 2022 with CiteSpace and VOSviewer. Our cluster analysis revealed key themes. 1) Language comprehension loss due to brain injury: Studies exploring the impact of brain injuries on language comprehension and underlying neural mechanisms. 2) Right hemisphere damage and pragmatic language skills: Research focusing on the relationship between right hemisphere damage and pragmatic language abilities, investigating impairments in social language use and potential neural correlates. 3) Traumatic brain injury and social communication assessment: Research on traumatic brain injury effects on social communication skills, using various assessment tools to evaluate communication effectiveness in social situations. These clusters provide valuable insights into the neuropragmatics field and serve as a framework for future investigations. By building upon existing knowledge, researchers can improve our understanding of brain functions, language behavior, and enhance rehabilitation for individuals with pragmatic language impairments.

Descriptive discourse in fluent aphasia: The predictive role of attention, phonology, lexical retrieval and semantics

AIMS

To study the relationship between cognitive and linguistic skills (as measured through standardized tasks) over spontaneous speech elicited during a picture description task.

METHODS & PROCEDURES

21 controls and 19 people with fluent aphasia matched by age and sex were evaluated using transcripts made from a picture description task coded using the CHAT format and analyzed using Computerized Language Analysis (CLAN). Indices obtained from the speech samples contained measures of lexical quantity and diversity, morphosyntactic complexity, informativeness, and speech fluency, along with different kinds of speech errors. We studied their correlations with attentional measures from Conners' Continuous Performance Test and with standardized measures of naming, pseudoword repetition and semantic non-verbal association. We further used stepwise linear regression to analyze the predictive value of standardized linguistic and cognitive skills over discursive indices.

OUTCOMES & RESULTS

Contrary to our initial hypothesis, there were no significant correlations between attentional scores and discourse variables in aphasic participants. Moreover, semantic association, along with naming, was the measure more related with discourse performance in people with fluent aphasia, but cognitive and linguistic standardized measures had overall little predictive power on most discourse indices. In the control group, there was a certain association of naming skills and attentional reaction time with discourse variables, but their predictive power was also low.

CONCLUSIONS & IMPLICATIONS

The current results do not support a strong relationship between basic attentional skills and performance in descriptive discourse in fluent aphasia. Although some of the standardized tasks seem to bear some relationship with spontaneous speech, there is a high amount of interindividual variability in discourse that is not captured by classical cognitive tasks routinely used in assessment. Further work on the determinants of discourse performance in aphasia and on the clinical application of discourse analysis is warranted.

Analysis of narrative discourse structure as an ecologically relevant measure of executive function in adults

This study examined the narrative discourse production and executive function (EF) abilities of 46 neuro-typical adults (18-98 years old). Two questions were addressed: Is the analysis of narrative structure sensitive to changes associated with aging? & What is the relationship between measures of narrative structure and EF? Narratives were elicited under two conditions and narrative structure was analyzed for the presence of organizing story grammar elements. Narrative structure was significantly correlated with age as well as linguistic and non-linguistic measures of EF. Factor analysis of story structure and EF variables yielded two factors reflecting constructs of output-fluidity and organizational-efficiency. These data suggest that narrative structure and EF represent aspects of goal-directed knowledge that are not bound by a traditional linguistic and non-linguistic division. Thus, narrative structure may represent a global and ecologically valid measure of goal-directed executive function knowledge that is also sensitive to changes associated with typical aging.

Organizational Structure Reduces Processing Load in the Prefrontal Cortex During Discourse Processing of Written Text: Implications for High-Level Reading Issues After TBI

Adults with traumatic brain injury (TBI) can demonstrate marked difficulty producing discourse during story retell and story generation tasks. Changes in discourse production have been detailed in terms of fewer content units and infrequent use of story grammar elements essential for organization. One implication is that poor use of story grammar elements during discourse production may signal reduced ability to utilize these elements in other communication realms (e.g., reading comprehension). The neural architecture that supports discourse organization, primarily the medial prefrontal cortex, is particularly susceptible to damage secondary to acquired brain injury. In this event related functional magnetic resonance imaging (fMRI) study, we describe cortical activation patterns of unimpaired readers as they are presented with discourse that is varied in terms of structural organization. The results suggest reading discourse with less structure is associated with increased cortical activity (e.g., higher processing demands) as compared to reading discourse with more traditional structural cues (e.g., story grammar). We discuss cortical areas implicated and potential implications for supporting discourse communication in persons following TBI.

The Impact of Varied Speaker Role and Communication Partner on the Communicative Interactions of a Person With Traumatic Brain Injury: A Single Case Study Using Systemic Functional Linguistics

This article presents preliminary findings on an investigation into the differences in communicative performance across varying speaking conditions, of an individual with a cognitive–linguistic impairment following traumatic brain injury (TBI). The article compares the communicative exchanges of an individual in a conversation with a therapist, a conversational dyad with a peer with TBI, and in a communication group task where they were interacting with other participants with TBI. The speaking conditions studied included an unstructured chat, the participant requesting information and the participant giving information. Results showed that the person with TBI responded to differences in communication partner and speaker role. He was best able to give information in the unstructured chat with the clinician and the information giving session in the group. Requesting was maximally facilitated in the information request condition with the clinician. Qualitatively, however, the most equal interactions occurred with the peer, with evidence of the person with TBI engaging in typical conversational strategies such as establishing common ground to facilitate topic development and co-constructing the discourse topics. These strategies did not occur in the clinician or group interactions, possibly due to power imbalance in the former and impaired cognitive–linguistic ability in the latter situation. Implications for clinical decision making regarding intervention strategies for patients with cognitive–communication deficits are discussed.

Higher-order reasoning training years after traumatic brain injury in adults

OBJECTIVE

To conduct a feasibility study to compare the effects of top-down Strategic Memory and Reasoning Training (SMART) versus information-based Brain Health Workshop (BHW, control) on gist-reasoning (ie, abstracting novel meaning from complex information), memory, executive functions, and daily function in adults with traumatic brain injury.

PARTICIPANTS

Twenty-eight participants (of the 35 recruited), 16 men & 12 women, aged 20 to 65 years (M = 43, SD = 11.34) at chronic stages posttraumatic brain injury (2 years or longer) completed the training. Fourteen participants that received SMART and 14 participants that completed BHW were assessed both pre- and posttraining. Thirteen of the SMART trained and 11 from BHW participated in a 6-month testing.

DESIGN

The study was a single blinded randomized control trial. Participants in both groups received a minimum of 15 hours of training over 8 weeks.

RESULTS

The SMART group significantly improved gist-reasoning as compared to the BHW group. Benefits of the SMART extended to untrained measures of working memory and participation in functional activities. Exploratory analyses suggested potential transfer effects of SMART on memory and executive functions. The benefits of the SMART program as compared to BHW were evident at immediately posttraining and 6 months posttraining.

CONCLUSION

This study provides preliminary evidence that short-term intensive training in top-down modulation of information benefits gist-reasoning and generalizes to measures of executive function and real life function at chronic stages of post-TBI.

Conversation after right hemisphere brain damage: motivations for applying conversation analysis

Despite the well documented pragmatic deficits that can arise subsequent to Right Hemisphere Brain Damage (RHBD), few researchers have directly studied everyday conversations involving people with RHBD. In recent years, researchers have begun applying Conversation Analysis (CA) to the everyday talk of people with aphasia. This research programme has provided novel insights into the complex inter-relationship between impairment, language use, and interactional organization. This paper will argue that the detailed, inductive approach of CA is well suited to investigating pragmatic communication disorders resulting from RHBD, and will help to elaborate previous findings about RHBD and conversation. In particular, this paper will review and discuss previous investigations of conversation after RHBD, and put forward arguments relating to how CA might be applied to talk-in-interaction involving people with RHBD.

[Communication, language and the brain: from past anterior to near future]

The goal of this article is to share some reflection on the astonishing evolution of the ideas in communication neuroscience and neurolinguistics over the last 30 years, since the founding of the société de neuropsychologie de langue française. in particular, a number of conceptual and methodological advancements have characterized this period, many of which have been lead or heavily contributed by french-speaking research groups in that field. among the advances discussed, are (a) the widening to discourse and pragmatic components of the concept of language, as well as the theoretical and clinical implication of this conceptual extension, (b) the unique contribution of anatomical and functional neuroimaging, (c) the massive impact of the cognitive revolution on theoretical frameworks of language components, and its influence on therapy, (d) the disappearance and the re-appearance of the brain in the main stream research on language over this period, (e) the new perspectives offered though attention put on social aspects of language and the social participation of the individual with language disorders, (f) the emergence of a genuine science of aphasia rehabilitation, and (g) the rediscovery of inter-individual characteristics both genetically- and environmentally- determined. The authors then risk themselves in trying to envision what could characterize the evolution in the field for the next 30 years. Though perilous, this speculative exercise allowed to pinpoint to a number of anticipated advancements including (a) a probable reconciliation between cognitive and connectionist models to the benefit of both visions, (b) an increased contribution of social and emotional neurosciences, (c) some inescapable technological advancements, including light portable neuroimaging devices which will allow to study the neurobiological bases of communication in natural contexts, (d) the integration between communication and aging in cognitive neuroscience and (e) the development of new research fields at some unexpected cross-roads (e.g., physical activity and communication ?) as well as the description of new types of aphasia (e.g., towards a chat aphasia !). Taken together, the advancements made over the 30 last years, and the perspective of future development, confirms the premier role of cognitive neuroscience of language and neurolinguistics in setting the pace through innovative approaches that allow unveiling the mysteries of the mutual relationships between brain and cognition.

Two new scales of formal thought disorder in schizophrenia

Information provided by patients and respective carers may help to understand formal thought disorder (FTD) in schizophrenia. Two scales, one for patients (FTD-patient) and one for carers (FTD-carer), were constructed to assess pragmatics, cognitive, paralinguistic, and non-verbal aspects of communication. In the first scale the patients themselves assess their verbal communication; in the second scale the carer assesses the speech of the respective patient. Both scales exhibited internal reliability and evidence of good test-retest reliability. Higher total scores on both scales (FTD-patient and FTD-carer) were significantly associated with positive FTD, but not with negative FTD. Principal component analysis of the scales yielded a multidimensional structure. It is suggested that FTD in schizophrenia may be associated with a range of deficits (e.g. pragmatics, lexical activation, working memory, sustained attention). These scales, in conjunction with the clinician's assessment, can provide a more comprehensive picture of FTD in schizophrenia, revealing its dimensions and making it possible to establish associations between symptoms of FTD and neuropsychological, neurophysiologic, and neuroimaging data. In addition, they provide service users' and carers' perspectives for the assessment of communication in schizophrenia.

Self-referential tags in the discourse of people with Alzheimer's disease

In a study of the discourse of 100 people with Alzheimer's disease treated for 12 months with donepezil, we observed that, as a group, they used a form of tag, described here as a self-referential tag (SRT), 14 times more frequently than did caregivers. Patients use SRTs to check propositions dependent on episodic memory as in I haven't seen the doctor recently, have I? and to monitor information flow as in I told you that already, didn't I? Based on criteria developed for distinguishing checking from monitoring tags, we document the type and frequency of patients' SRT use in the ACADIE corpus and analyze these in relation to standard measures of cognitive function (Mini Mental State Exam and Alzheimer's Disease Assessment Scale-cognitive sub-scale) at baseline and 12 months. Patients using monitoring SRTs (N=31), with or without checking SRTs, show significantly better cognitive test scores at 12 months, than are seen in patients who never use tags (N=29), or who only use checking tags (N=40). SRT use may be an independent measure of potential treatment responsiveness.

Narrative and procedural discourse production by severely aphasic patients

Five cbronically aphasic subjects were trained on a computerized iconographic communication system (C-VIC). Their performance in producing single sentences scripts. and narratives was assessed using both spoken English and C-VIC. The requisite vocabulary necessary and the narrative complexity of the target productions were controlled. Subject performance using C-VIC indicates that the ability to construct discourse at the macrostructural level is largely intact. Despite significant improvements in spoken production after C-VIC training, especially at the single sentence level, the subjects' spoken discourse remains severely impaired by their failures at the microlinguistic level. These results point to the limits of currently available approaches to the remediation of aphasia and suggest avenues for future research.

Text comprehension after brain injury: left prefrontal lesions affect inference processes

Comprehending language in context requires inferencing, particularly for the establishment of local coherence. In the neurolinguistic literature, an inference deficit after right hemisphere brain damage has been postulated, but clinical observation and imaging data suggest that left-frontal lesions might also result in inference deficits. In the present experiment, 25 nonaphasic patients performed a coherence judgment task requiring them to indicate a pragmatic connection between 2 successively presented sentences. Patients with left-temporal or right-frontal lesions performed the task well. In contrast, patients with left- and bifrontal lesions exhibited the most severe deficit. Both error rates and response times were elevated for coherent trials as compared with incoherent trials. These results confirm that the left-frontal lobe contributes to inference processes.

The role of coherence and cohesion in text comprehension: an event-related fMRI study

Text processing requires inferences for establishing coherence between successive sentences. In neuropsychological studies and brain imaging studies, these coherence-building processes have been ascribed to the right hemisphere. On the other hand, there is evidence for prefrontal brain damage causing non-aphasic language disorders, in which text level processes are impaired. In this study, we used an event-related, whole-head fMRI methodology to evaluate the contributions of prefrontal areas and the right hemisphere to coherence building. We scanned 12 participants while they read 120 sentence pairs and judged their coherence. Four conditions were used, resulting from crossing coherence and cohesion (i.e. the presence of a lexical connection). A behavioral pretest confirmed that cohesion aided establishing coherence, whereas it hindered the detection of coherence breaks. In the fMRI study, all language conditions yielded activation in left frontolateral and temporolateral regions, when compared to a physical control task. The differences due to coherence of the sentence pairs were most evident in larger activation for coherent as compared to incoherent sentence pairs in the left frontomedian wall, but also in posterior cingulate and precuneal regions. Finally, a left inferior prefrontal area was sensitive to the difficulty of the task, and in particular to the increase in processing costs when cohesion falsely indicated coherence. These results could not provide evidence for a special involvement of the right hemisphere during inferencing. Rather, they suggest that the left frontomedian cortex plays an important role in coherence building.