Exploring the cognitive basis of right-hemisphere pragmatic language disorders

Pragmatic Communication Deficit and Functional Outcome in Patients with Right- and Left-Brain Damage: A Pilot Study

Pragmatic communication abilities refer to the capacity to use language in a social context. Despite evidence to the contrary, the left cerebral hemisphere of the majority of right handers has been considered exclusively specialized for control of language phonology, syntax and semantics, whereas the right hemisphere has been specialized for the control of language pragmatics. Many studies have shown the non-exclusivity of the left hemisphere for language skills. Communication deficits observed in these studies for patients with right hemisphere damage confirmed the necessity for integrity of the right hemisphere across a number of language components. The aim of this study is to investigate the specific role of the right and left hemispheres across several aspects of communication deficits, with particular attention given to the influence of these deficits on functional outcome. The second aim is to characterize possible correlations between pragmatic and other cognitive deficits. We evaluated 22 patients, 15 with left- and 7 with right-brain ischemic or hemorrhagic damage, using cognitive, pragmatic and language tests. We deployed the Right Hemisphere Language Battery-Santa Lucia and Montreal d'Evaluation de la Communication to assess pragmatic abilities. The results showed no statistically significant differences between patients with left- and right-brain damage, highlighting the importance of integration between the two hemispheres in the communication process. Multiple significant correlations were found between pragmatic abilities and cognitive tests assessing global cognitive functioning, pantomime expression and comprehension. Pragmatic deficits were also shown to correlate with functional cognitive outcome. It is important to assess pragmatic abilities in patients with cognitive deficits after both left and right stroke for tailoring neuropsychological intervention to mitigate pragmatic disabilities in functional outcomes.

Pragmatic language comprehension: Role of theory of mind, executive functions, and the prefrontal cortex

The specific contribution of focal damage of the prefrontal cortex and the cognitive mechanisms accounting for communicative-pragmatic disorders remains unclear. The objective of the current study was to investigate the impact of focal prefrontal cortex damage on the ability to understand indirect speech or hints and to identify the prefrontal neural mechanisms involved. We also examined the underlying cognitive mechanisms of disorders of indirect speech understanding particularly theory of mind and executive functions. Thirty patients with focal prefrontal cortex damage and 30 control subjects were compared on their performances on the Hinting task assessing pragmatic language skills, the "Faux-Pas" task and the Reading the Mind in the Eyes task assessing Theory of Mind and a battery of executive tasks. Patients were significantly impaired compared with control subjects on all these abilities. Both deficits of executive functions and theory of mind were able to predict impaired ability of patients in understanding non-literal meanings on the Hinting task. Finally, using voxel-based lesion analysis we identified a partially shared neural prefrontal network involved in all these abilities centered on the dorsomedial and ventral regions of the prefrontal cortex.

Exploring Cognitive-Pragmatic Heterogeneity Following Acquired Brain Injury: A Cluster Analysis of Hint Comprehension

PURPOSE

Difficulties understanding nonliteral language (especially hints) are frequently reported following acquired brain injury (ABI). Several cognitive mechanisms, such as context processing, executive functions, and theory of mind (ToM), may underlie these disorders. However, their role remains controversial, mainly because of the characteristic heterogeneity of this population. Therefore, our study aimed to identify cognitive-pragmatic profiles in individuals with ABI.

METHOD

A new task of hint comprehension, manipulating executive demand, markers of hints, and ToM and neuropsychological tests were administered to 33 participants with frontal ABI and 33 control participants. Cluster analysis, a method sensitive to profile heterogeneity, was applied and coupled with error analysis.

RESULTS

We highlighted two cognitive-pragmatic profiles. One subgroup of participants with ABI exhibited contextual insensitivity, leading them to infer the utterance meaning based on linguistic decoding alone-literal meaning. This difficulty in understanding hints was associated with deficits in working memory, inhibition, and ToM. The second subgroup of participants with ABI showed difficulty with literal statements, associated with impaired inhibition and ToM. In addition, the two subgroups differed only on the ToM task. This result suggests that various types of ToM deficit (misunderstanding vs. incorrect attribution of mental states) could contribute to the variability of the pragmatic profiles observed (difficulties in interpreting hints vs. literal statements).

CONCLUSION

The experimental design adopted in this study provides valuable insight into the explanatory hypotheses of nonliteral language comprehension disorders and has important clinical implications.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.24069516.

Pragmatic deficits in patients with schizophrenia and right hemisphere damage: A pilot study

BACKGROUND

While pragmatic deficits are well documented in patients with schizophrenia (SCZ) and right hemisphere damage (RHD), there is a paucity of research comparing the pragmatic deficits of these two groups. Do they experience similar cognitive dysfunction or is there a dissociation between the two patient groups?

AIMS

To investigate the nature of pragmatic deficits in these two groups and to gain an understanding of the underlying cognitive mechanisms that might be associated with these deficits to further future investigations.

METHODS & PROCEDURES

A total of 60 participants (15 patients with SCZ; 15 with RHD; 30 (15 + 15) healthy controls (HC) were administered the Bengali Audio-Visual Test-Battery for Assessment of Pragmatic Skills.

OUTCOMES & RESULTS

Both SCZ and RHD patients were found to have significant pragmatic deficits compared with their matched controls. SCZ patients were found to score significantly better than the RHD group in six out of the 10 pragmatic skills when controlled for age and education. Discriminant function analysis was performed and 86.7% of the cases (HC = 100%, SCZ = 73.3% and RHD = 86.7%) were correctly reclassified into their original categories using the test scores.

CONCLUSIONS & IMPLICATIONS

The study suggests that there is heterogeneity in the nature of the pragmatic breakdown within and across patient groups. Therefore, individualized restorative measures targeting the disrupted cognitive mechanism(s) might help elevate pragmatic competence and enhance the social functioning of patients with pragmatic deficits.

WHAT THIS PAPER ADDS

What is already known on the subject Pragmatic deficits are common in adults with cognitive impairments of different etiologies. However, few studies have explored pragmatic deficits across clinical populations. Consequently, very little is known about the nature of pragmatic deficits in patients with schizophrenia and right hemisphere damage. What this paper adds to existing knowledge This work offers preliminary data on pragmatic difficulties in patients with schizophrenia and right hemisphere damage. This study overrides the boundaries of traditional classifications and evaluates pragmatic difficulties in these two clinical populations with reference to the underlying cognitive mechanisms, which might be disrupted. What are the potential or actual clinical implications of this work? The study adds a transdiagnostic perspective suggesting that there might be heterogeneity in pragmatic deficits, both within and across patient groups, and stresses the need for individualized therapy.

An Analysis of Right Hemisphere Stroke Discourse in the Modern Cookie Theft Picture

PURPOSE

Adults with right hemisphere damage demonstrate differences in connected speech compared to controls, but systematic, quantitative methods to capture these differences are lacking. The current study aimed to (a) investigate if measures using the Modern Cookie Theft picture description would identify discourse differences in acute right hemisphere stroke, and (b) examine if discourse differences were associated with documented cognitive impairment.

METHOD

Eighty-four participants completed the Modern Cookie Theft picture description within 5 days of right hemisphere stroke. Descriptions were analyzed for multiple microlinguistic characteristics. Medical charts were retrospectively reviewed for documented presence of cognitive impairment.

RESULTS

Individuals with acute right hemisphere stroke produced fewer content units, total syllables, and lower left-right content unit ratios compared to controls, indicating a paucity of informativeness. Presence of cognitive impairment was associated with fewer content units produced.

CONCLUSIONS

Multiple measures of microlinguistic discourse characteristics differentiated adults with right hemisphere stroke from controls, highlighting variations in both the quantity and quality of connected speech. Findings continue to underscore the contribution and correlation between cognitive skills and discourse performance. Future work is needed to assess the relationship between particular cognitive domains and discourse production as well as to investigate longitudinal changes to discourse production during stroke recovery.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.20778541.

An ERP study of hemispheric differences in perceptual representations of language reveals meaning attribution in the right hemisphere and constituents of the N400-effect

Recent findings have revealed that the right hemisphere (RH) is uniquely involved in integrating perceptual information from linguistic input to simulate a mental model of that input. We extend on these findings by testing whether meaning is generated from such models. Participants (N = 37) heard auditory passages describing the visuospatial arrangement of elements into a perceptual representation of a familiar object, then judged whether a laterally-presented target word matched the object. We found a central N400-effect for left visual-field targets, suggesting that meaning was also accessible to the RH. There was no statistical difference for right visual-field targets. Principle component analysis of the data revealed that the N400-effect was driven by positive components. Consequently, the results suggest that i) RH contributions to language comprehension include integrative and perceptual processes that enable overall meaning to be generated from representations of discourse, and ii) positive ERP components may produce N400-effects.

Pragmatic Language Disorder in Parkinson's Disease and the Potential Effect of Cognitive Reserve

It is known that patients with Parkinson's Disease (PD) may show deficits in several areas of cognition, including speech and language abilities. One domain of particular interest is pragmatics, which refers to the capacity of using language in context for a successful communication. Several studies showed that some specific aspects of pragmatics - both in production and in comprehension - might be impaired in patients with PD. However, a clear picture of pragmatic abilities in PD is still missing, as most of the existing studies focused on specific aspects of the pragmatic competence rather than on sketching a complete pragmatic profile. Moreover, little is known on the potential role of protective factors in compensating the decline of communicative skills as the disease progresses. The present study has two aims: (1) to provide a complete picture of pragmatic abilities in patients with PD, by using a comprehensive battery (Assessment of Pragmatic Abilities and Cognitive Substrates, APACS) and by investigating the relationship with other aspects of cognitive functioning (e.g., working memory and Theory of Mind) and (2) to investigate whether Cognitive Reserve, i.e., the resilience to cognitive impairment provided by life experiences and activities, may compensate for the progressive pragmatic deficits in PD. We found that patients with PD, compared to healthy matched controls, had worse performance in discourse production and in the description of scenes, and that these impairments were tightly correlated with the severity of motor impairment, suggesting reduced intentionality of engaging in a communicative exchange. Patients with PD showed also an impairment in comprehending texts and humor, suggesting a problem in inferring from stories, which was related to general cognitive impairment. Notably, we did not find any significant difference between patients and controls in figurative language comprehension, a domain that is commonly impaired in other neurodegenerative diseases. This might be indicative of a specific profile of pragmatic impairment in patients with PD, worth of further investigation. Finally, Cognitive Reserve measures showed a high degree of association with pragmatic comprehension abilities, suggesting that the modification of life-styles could be a good candidate for compensating the possible problems in understanding the pragmatic aspects of language experienced by patients with PD.

Executive functions assessment in patients with language impairment A systematic review

Acquired language impairments may accompany different conditions. Most recent studies have shown that there is an important relationship between language and cognitive functions, such as executive functions (EF). Therefore, we aimed to investigate which main EF components appear to have the greatest impact in the most prevalent acquired communication disorders in adults, and which neuropsychological tests are being used to evaluate them. In addition, we sought to characterize the relationship between the executive functions and language in these conditions. Working memory (WM) was the most frequently chosen cognitive measure, being evaluated by different span tasks. A relationship between WM and narrative and conversational discourse, writing abilities and grammatical comprehension was found. Other currently used cognitive tests included the Trail Making, Wisconsin, Stroop and Verbal Fluency tests. Language and EF have a complex relationship; hence, a complete assessment should reflect the dynamic processing of cognitive brain functions.

Higher-order language dysfunctions as a possible neurolinguistic endophenotype for schizophrenia: Evidence from patients and their unaffected first degree relatives

The purpose of the study was to examine the presence of pragmatic dysfunctions in first episode (FE) subjects and their healthy first degree relatives as a potential endophenotype for schizophrenia. Thirty-four FE patients, 34 parents of the patients (REL) and 32 healthy controls (HC) took part in the study. Pragmatic language functions were evaluated with the Right Hemisphere Language Battery, attention and executive functions were controlled, as well as age and education level. The parents differed from HC but not from their FE offspring with regard to overall level of language and communication and the general knowledge component of language processing. The FE participants differed from HC in comprehension of inferred meaning, emotional prosody, discourse dimensions, overall level of language and communication, language processing with regard to general knowledge and communication competences. The FE participants differed from REL regarding discourse dimensions. Our findings suggest that pragmatic dysfunctions may act as vulnerability markers of schizophrenia; their assessment may help in the diagnosis of early stages of the illness and in understanding its pathophysiology. In future research the adoptive and biological parents of schizophrenia patients should be compared to elucidate which language failures reflect genetic vulnerability and which ones environmental factors.

The Affective Nature of Formulaic Language: A Right-Hemisphere Subcortical Process

Formulaic expressions naturally convey affective content. The unique formal and functional characteristics of idioms, slang, expletives, proverbs, conversational speech formulas, and the many other conventional expressions in this repertory have been well-described: these include unitary form, conventionalized and non-literal meanings, and reliance on social context. Less highlighted, but potent, is the intrinsic presence of affective meaning. Expletives, for example, signal strong emotion. Idioms, too, inherently communicate emotional connotations, and conversational speech formulas allow for empathetic bonding and humor. The built-in affective content of formulaic expressions, in combination with their other unique characteristics, is compatible with the proposal that brain structures other than those representing grammatical language are in play in producing formulaic expressions. Evidence is presented for a dual process model of language, whereby a right hemisphere-subcortical system modulates formulaic language.

Inference comprehension in text reading: Performance of individuals with right- versus left-hemisphere lesions and the influence of cognitive functions

Background

Right-hemisphere lesions (RHL) may impair inference comprehension. However, comparative studies between left-hemisphere lesions (LHL) and RHL are rare, especially regarding reading comprehension. Moreover, further knowledge of the influence of cognition on inferential processing in this task is needed.

Objectives

To compare the performance of patients with RHL and LHL on an inference reading comprehension task. We also aimed to analyze the effects of lesion site and to verify correlations between cognitive functions and performance on the task.

Methods

Seventy-five subjects were equally divided into the groups RHL, LHL, and control group (CG). The Implicit Management Test was used to evaluate inference comprehension. In this test, subjects read short written passages and subsequently answer five types of questions (explicit, logical, distractor, pragmatic, and other), which require different types of inferential reasoning. The cognitive functional domains of attention, memory, executive functions, language, and visuospatial abilities were assessed using the Cognitive Linguistic Quick Test (CLQT).

Results

The LHL and RHL groups presented difficulties in inferential comprehension in comparison with the CG. However, the RHL group presented lower scores than the LHL group on logical, pragmatic and other questions. A covariance analysis did not show any effect of lesion site within the hemispheres. Overall, all cognitive domains were correlated with all the types of questions from the inference test (especially logical, pragmatic, and other). Attention and visuospatial abilities affected the scores of both the RHL and LHL groups, and only memory influenced the performance of the RHL group.

Conclusions

Lesions in either hemisphere may cause difficulties in making inferences during reading. However, processing more complex inferences was more difficult for patients with RHL than for those with LHL, which suggests that the right hemisphere plays an important role in tasks with higher comprehension demands. Cognition influences inferential processing during reading in brain-injured subjects.

Reviving pragmatic theory of theory of mind

Theory of Mind (ToM) refers to the ability to attribute mental states to self and others. It has been debated whether or not language capacity precedes ToM in development. Evidence from both neurological and developmental studies suggested that while linguistic capacity is important for ToM understanding, pragmatic component, which is a non-structural part of language, is more important for ToM. Moreover, given that pragmatic component of language is subserved by the right hemisphere of the brain, the evidence also indicates a significant overlap between the neural basis of ToM and that of pragmatic comprehension. The pragmatic theory of ToM, which I aim to revive in this review, firmly links pragmatics to ToM. It regards pragmatic aspects of language and ToM as extensively overlapping functions. I argue that research results from both developmental and neurological studies of ToM are beginning to converge to support this theory. Furthermore, I maintain that the pragmatic theory of ToM provides the best explanation for the seemingly incongruent results from recent child and infant studies on the developmental trajectory of ToM. Lastly, I will discuss whether this theory is in agreement with the domain-specific, the nativist framework, or neither.

Context processing during irony comprehension in right-frontal brain-damaged individuals

The aim of the present study was to investigate whether the degree of incongruity between contextual information and a target sentence influences the extent to which irony is understood in individuals with right-frontal-hemisphere damage (RHD). A psycholinguistic paradigm was used, allowing us to assess whether impairment in irony understanding is likely to be due to insensitivity (i.e. difficulty in capturing or detecting relevant contextual information) to relevant contextual information or to difficulties in integrating contextual information. Twenty individuals with RHD and 20 healthy control (HC) participants were tested on their understanding of a speaker's ironic intent and their executive functions. The main results revealed that individuals with RHD exhibit different patterns of performance, some of them being able to understand irony while in others this ability was impaired. The present study gives support to the hypothesis that difficulties in adequately using contextual information may account for pragmatic impairment of individuals with RHD. More importantly, the results suggested that these difficulties are related to a lack of sensitivity to contextual information instead of difficulty integrating it along with the ironic utterance. A subgroup of individuals with RHD processed the speaker's utterance without any reference to contextual information, which led them to a literal interpretation of the utterance.

Pragmatic Ability Deficit in Schizophrenia and Associated Theory of Mind and Executive Function

Deficits in pragmatic abilities have frequently been observed in patients with schizophrenia. The objective of the study was to investigate the relationship between pragmatic deficits, ToM deficits and executive dysfunctions in schizophrenia. A group of 42 schizophrenic patients and 42 healthy controls were assessed on irony task (one type of pragmatic language), two subcomponents of ToM (cognitive and affective), and three subcomponents of EF (inhibition, updating, and switching). The clinical symptoms in schizophrenia were assessed using the positive and negative symptoms of schizophrenia. The schizophrenia group exhibited significant impairments in all above tasks compared to the control group. Correlation results found that irony scores were correlated with the two subcomponents of ToM and two of the three subcomponents of EF (inhibition and updating). The regression analysis revealed that the cognitive ToM and inhibition predicted 9.2% and 29.9% of the variance of irony comprehension in the patient group, and inhibition was the best predictor for performance on irony task. Irony understanding was related to positive symptoms, but not to negative symptoms. The results suggest that the ability to interpret pragmatic language depends on schizophrenic patients' ability to infer mental states and the ability of inhibition. It provides empirical evidence for a particular target of inhibition for rehabilitation and intervention programs developed for schizophrenic patients.

Contribution of visuospatial attention, short-term memory and executive functions to performance in number interval bisection

Number interval bisection consists of estimating the mid-number within a pair (1-9=>5). Healthy adults and right-brain damage patients can show biased performance in this task, underestimating and overestimating the mid-number, respectively. The role of visuospatial attention during this task, and its interplay with other cognitive abilities (e.g., working memory) is still object of debate. In this study we explored the relation between visuospatial attention and individual differences in working memory and executive functions during number interval bisection. To manipulate the deployment of visuospatial attention, healthy participants tracked a dot moving to the left or moving to the right while bisecting numerical intervals. We also collected information concerning verbal and visuospatial short-term memory span, and concerning verbal and visuospatial fluency scores. Beside replicating what is typically observed in this task (e.g., underestimation bias), a correlation was observed between verbal short-term memory and bisection bias, and an interesting relation between performance in the number interval bisection, verbal short-term memory, and visuospatial attention. Specifically, performance of those participants with low verbal span was affected by the direction of the moving dot, underestimating at a larger extent when the dot moved leftward than rightward. Finally, it was also observed that participants' verbal fluency ability contributed in the generation of biases in the numerical task. The finding of the involvement of abilities belonging to the verbal domain contributes to unveil the multi-componential nature of number interval bisection. Considering the debate on the nature of number interval bisection and its use in the clinical assessment of deficits following brain damage, this finding may be interesting also from a clinical perspective.

Communication Abilities Following Right Hemisphere Damage: Prevalence, Evaluation, and Profiles

It is now consensually accepted that the contribution of both hemispheres is required to reach a functional level of communication. The unilateralized view of language function, introduced more than a century ago, has since been complemented by clinical experience as well as neuro-imaging observations. Studies based on healthy and right-brain-damaged individuals assert the necessity to better describe, assess, and care for this broad population. Indeed, various neurological conditions, including stroke, traumatic brain injury (TBI), or neurodegenerative disease, can affect the right hemisphere (RH) and lead to distinct communication disorders. In the past 30 years, knowledge about communication assessment and, more recently, therapy designed for right-brain-damaged adults has drastically evolved. This manuscript aims at presenting the theoretical and clinical background that established the current expertise to support accurate assessment of communication following right brain damage. It is believed that a better understanding of the various profiles of impairments following a RH infract will allow speech-language pathologists (SLPs) to develop the clinical awareness necessary for appropriately taking care of these individuals.

You may now kiss the bride: Interpretation of social situations by individuals with right or left hemisphere injury

While left hemisphere damage (LHD) has been clearly shown to cause a range of language impairments, patients with right hemisphere damage (RHD) also exhibit communication deficits, such as difficulties processing prosody, discourse, and social contexts. In the current study, individuals with RHD and LHD were directly compared on their ability to interpret what a character in a cartoon might be saying or thinking, in order to better understand the relative role of the right and left hemisphere in social communication. The cartoon stimuli were manipulated so as to elicit more or less formulaic responses (e.g., a scene of a couple being married by a priest vs. a scene of two people talking, respectively). Participants' responses were scored by blind raters on how appropriately they captured the gist of the social situation, as well as how formulaic and typical their responses were. Results showed that RHD individuals' responses were rated as significantly less appropriate than controls and were also significantly less typical than controls and individuals with LHD. Individuals with RHD produced a numerically lower proportion of formulaic expressions than controls, but this difference was only a trend. Counter to prediction, the pattern of performance across participant groups was not affected by how constrained/formulaic the social situation was. The current findings expand our understanding of the roles that the right and left hemispheres play in social processing and communication and have implications for the potential treatment of social communication deficits in individuals with RHD.

Brain basis of communicative actions in language

Although language is a key tool for communication in social interaction, most studies in the neuroscience of language have focused on language structures such as words and sentences. Here, the neural correlates of speech acts, that is, the actions performed by using language, were investigated with functional magnetic resonance imaging (fMRI). Participants were shown videos, in which the same critical utterances were used in different communicative contexts, to Name objects, or to Request them from communication partners. Understanding of critical utterances as Requests was accompanied by activation in bilateral premotor, left inferior frontal and temporo-parietal cortical areas known to support action-related and social interactive knowledge. Naming, however, activated the left angular gyrus implicated in linking information about word forms and related reference objects mentioned in critical utterances. These findings show that understanding of utterances as different communicative actions is reflected in distinct brain activation patterns, and thus suggest different neural substrates for different speech act types.

The role of executive functions in the pragmatic skills of children age 4-5

Several studies suggest that pragmatic skills (PS) (i.e., social communication) deficits may be linked to executive dysfunction (i.e., cognitive processes required for the regulation of new and complex behaviors) in patients with frontal brain injuries. If impairment of executive functions (EF) causes PS deficits in otherwise healthy adults, could this mean that EF are necessary for the normal functioning of PS, even more so than cognitive maturation? If so, children with highly developed EF should exhibit higher levels of PS. This study aimed to examine the link between EF and PS among normally developing children. A secondary goal was to compare this relationship to that between intellectual quotient (IQ) and PS in order to determine which predictor explained the most variance. Participants were 70 French-speaking preschool children (3;10–5;7 years old). The PS coding system, an observational tool developed for this study, was used to codify the children's PS during a semi-structured conversation with a research assistant. Five types of EF processes were evaluated: self-control, inhibition, flexibility, working memory and planning. IQ was estimated by tallying the scores on a receptive vocabulary test and a visuoconstructive abilities test. The results of the test of differences between correlation coefficients suggest that EF contributed significantly more than IQ to the PS exhibited by preschoolers during conversation. More specifically, higher inhibition skills were correlated with a decrease in talkativeness and assertiveness. EF also appeared to foster quality of speech by promoting the ability to produce fluid utterances, free of unnecessary repetition or hesitation. Moreover, children with a high working memory capacity were more likely to formulate contingent answers and produce utterances that could be clearly understood by the interlocutor. Overall, these findings help us better understand how EF may assist children in everyday social interactions.

An evidence-based systematic review on communication treatments for individuals with right hemisphere brain damage

PURPOSE

The purpose of this review is to evaluate and summarize the research evidence related to the treatment of individuals with right hemisphere communication disorders.

METHOD

A comprehensive search of the literature using key words related to right hemisphere brain damage and communication treatment was conducted in 27 databases (e.g., PubMed, CINAHL). On the basis of a set of pre-established clinical questions, inclusion/exclusion criteria, and search parameters, studies investigating sentence- or discourse-level treatments were identified and evaluated for methodological quality. Data regarding participant, intervention, and outcome variables were reported.

RESULTS

Only 5 studies were identified, each representing a different sentence- or discourse-level treatment approach and reporting a wide range of prosodic, expressive, receptive, and pragmatic outcomes.

CONCLUSION

Although the state of the evidence pertaining to right hemisphere communication treatments is at a very preliminary stage, some positive findings were identified to assist speech-language pathologists who are working with individuals with right hemisphere brain damage. Clinical implications and recommendations for future research are explored.

That Can't Be Right! What Causes Pragmatic Language Impairment Following Right Hemisphere Damage?

Right hemisphere damage (RHD) following unilateral stroke is often associated with impairment of pragmatic language, specifically, the ability to comprehend inferences that arise from language used in context. Three kinds of cognitive deficits have been proposed to explain the pragmatic deficits in RHD individuals, impaired Theory of Mind (TOM), weak central coherence (CC), and impaired executive function (EF). This study aims to evaluate the explanatory ability of these theories in relation to the comprehension of nonliteral (ironic) jokes versus literal lies. Twenty-one RHD patients and 21 age-matched controls were assessed on tasks tapping TOM, CC processing and general inference ability (EF) and the comprehension of irony. Second-order TOM and EF were found to play a significant role. However, neither construct, either in isolation or combined, completely explained the poor performance of RHD patients on this task compared to control participants.

Everyday Talk: Its Role in Assessment and Treatment for Individuals With Aphasia

This article discusses the significance of conversation in current clinical practice with individuals with aphasia and their conversation partners. It explores the nature of everyday talk, and provides an overview of how studies to date have examined the conversations of individuals with aphasia and have provided some promising treatment avenues. It also proposes another framework, Speech Function Analysis, that may assist further in incorporating conversational principles into the therapy context. The framework provides a system network for examining speech functions in dialogue, while considering the effects of both lexical and syntactic limitations, and context. Examples of conversations between three individuals with aphasia and their partners are used to illustrate the analysis. The authors suggest that further knowledge of both aphasic speakers' and their partners' interactions as well as clinician–client interactions may increase our insights into this area, and make authentic and meaningful conversation more accessible in the clinical situation and beyond.

The New Age of Communication Research: Discourse, Cognition and Behaviour

Research into communication disorders has been undergoing a slow revolution over the past few decades with some fascinating advances and some exciting new directions ahead. The major change in emphasis that has emerged is an interest in assessing communication as this relates to real-life everyday type situations. In particular, three major thrusts can be identified. The first is the application of socially relevant linguistic theory to communication disorders. Thus, theorists such as Halliday have provided useful frameworks for identifying patterns in discourse. In turn, these have revealed the strengths and weakness of speakers with aphasia or other communication disorders (e.g., traumatic brain injuries) and also what their conversational partners do to help or hinder this process. The second is an examination of how cognitive processes, including memory, inferential reasoning and social cognition, contribute to communicative competence in people who have communication disorders but not aphasia, such as those with Alzheimer's disease, with traumatic brain injuries and with right hemisphere lesions. The third is the adoption of a more integrated approach, whereby verbal and nonverbal behaviours are examined in detail for their communicative meaning, for both the purposes of characterising communication breakdown and for developing an integrated treatment approach.

Terminology and Methodology in the Assessment of Cognitive-Linguistic Disorders

The term ‘cognitive-linguistic’ has been widely adopted in descriptions of a variety of communication disorders of neurogenic origin. Despite this, clear agreement on the meaning of the term has yet to be reached, with the result that it is used both inconsistently and misleadingly. This lack of terminological clarity also undermines the assessment of complex communicative function. In this article the terminology associated with complex communication disorders is discussed and a simple framework for conceptualising cognitive-linguistic function is outlined. On the basis of this it is proposed that some currently available assessments that purport to measure cognitive-linguistic skills in fact have less explanatory power than other assessments that are often not specifically targeted at communication. Further, it is suggested that the framework offers an ecologically valid basis for the systematic assessment of cognitive-linguistic function.

Pragmatic and executive functions in traumatic brain injury and right brain damage: An exploratory comparative study

OBJECTIVE

To describe the frequency of pragmatic and executive deficits in right brain damaged (RBD) and in traumatic brain injury (TBI) patients, and to verify possible dissociations between pragmatic and executive functions in these two groups.

METHODS

The sample comprised 7 cases of TBI and 7 cases of RBD. All participants were assessed by means of tasks from the Montreal Communication Evaluation Battery and executive functions tests including the Trail Making Test, Hayling Test, Wisconsin Card Sorting Test, semantic and phonemic verbal fluency tasks, and working memory tasks from the Brazilian Brief Neuropsychological Assessment Battery NEUPSILIN. Z-score was calculated and a descriptive analysis of frequency of deficits (Z< -1.5) was carried out.

RESULTS

RBD patients presented with deficits predominantly on conversational and narrative discursive tasks, while TBI patients showed a wider spread pattern of pragmatic deficits. Regarding EF, RBD deficits included predominantly working memory and verbal initiation impairment. On the other hand, TBI individuals again exhibited a general profile of executive dysfunction, affecting mainly working memory, initiation, inhibition, planning and switching. Pragmatic and executive deficits were generally associated upon comparisons of RBD patients and TBI cases, except for two simple dissociations: two post-TBI cases showed executive deficits in the absence of pragmatic deficits.

DISCUSSION

Pragmatic and executive deficits can be very frequent following TBI or vascular RBD. There seems to be an association between these abilities, indicating that although they can co-occur, a cause-consequence relationship cannot be the only hypothesis.

Semantic priming in a cortical network model

Contextual recall in humans relies on the semantic relationships between items stored in memory. These relationships can be probed by priming experiments. Such experiments have revealed a rich phenomenology on how reaction times depend on various factors such as strength and nature of associations, time intervals between stimulus presentations, and so forth. Experimental protocols on humans present striking similarities with pair association task experiments in monkeys. Electrophysiological recordings of cortical neurons in such tasks have found two types of task-related activity, "retrospective" (related to a previously shown stimulus), and "prospective" (related to a stimulus that the monkey expects to appear, due to learned association between both stimuli). Mathematical models of cortical networks allow theorists to understand the link between the physiology of single neurons and synapses, and network behavior giving rise to retrospective and/or prospective activity. Here, we show that this type of network model can account for a large variety of priming effects. Furthermore, the model allows us to interpret semantic priming differences between the two hemispheres as depending on a single association strength parameter.

Metanálise de estudos do processamento comunicativo em indivíduos com lesão vascular direita

Esta pesquisa apresenta estudos com indivíduos com lesão vascular no hemisfério direito, investigando-se o desempenho dessa população nos processamentos comunicativos discursivo, pragmático-inferencial, léxico-semântico e prosódico. A literatura de neuropsicologia atual tem enfocado cada vez mais as relações entre linguagem, comunicação, cognição e emoção através do estudo das funções do hemisfério direito em indivíduos com e sem lesão. Foram analisados os aspectos metodológicos e os resultados de 25 estudos das fontes Medline e Science Direct. Evidenciou-se que dos 357 lesados de hemisfério direito participantes, 330 (92,4%) apresentaram alterações quantitativas e/ou qualitativas nas habilidades comunicativas avaliadas. O hemisfério direito parece desempenhar um papel importante no processamento das habilidades comunicativas discursivas, pragmático-inferenciais, léxico-semânticas e prosódicas.

Perspectives on treatment for communication deficits associated with right hemisphere brain damage

PURPOSE

To describe the current treatment research for communication (prosodic, discourse, and pragmatic) deficits associated with right hemisphere brain damage and to provide suggestions for treatment selection given the paucity of evidence specifically for this population.

METHOD

The discussion covers (a) clinical decision processes and evidence-based practice; (b) a review of right hemisphere communication deficits and existing treatment studies; (c) accounts of right hemisphere function, right hemisphere deficits, and theoretically motivated treatments; and (d) a guide for exploring and selecting treatments based on deficits rather than etiology.

CONCLUSIONS

Controlled treatment studies for communication deficits specifically for adults with right hemisphere brain damage are limited to aprosodia. For other communication deficits, clinicians may select treatments based on current theories of right hemisphere function and right hemisphere deficits, and/or treatments developed for other etiologies for which deficits are similar to those associated with right hemisphere damage.

Conceptualizing Functional Cognition in Stroke

Background. Up to 65% of individuals demonstrate poststroke cognitive impairments, which may increase hospital stay and caregiver burden. Randomized stroke clinical trials have emphasized physical recovery over cognition. Neuropsychological assessments have had limited utility in randomized clinical trials. These issues accentuate the need for a measure of functional cognition (the ability to accomplish everyday activities that rely on cognitive abilities, such as locating keys, conveying information, or planning activities). Objective. The aim of the study was to present the process used to establish domains of functional cognition for development of computer adaptive measure of functional cognition for stroke. Methods. Functional cognitive domains involved in identifying relevant neuropsychological constructs from the literature were conceptualized and finalized after advisory panel feedback from experts in neurology, neuropsychology, aphasiology, clinical trials, and epidemiology. Results. The following 17 domains were proposed: receptive aphasia, expressive aphasia, agraphia, alexia, calculation, visuospatial, visuoperceptual, visuoconstruction, attention, language usage, executive functions, orientation, processing speed, memory, working memory, mood, awareness and abstract reasoning. The advisory panel recommended retaining the first 12 domains. Recommended changes included: to address only encoding and retrieval of recent information in the memory domain; to add domains for limb apraxia and poststroke depression; and to keep orientation as a separate domain or reclassify it under memory or attention. The final 10 domains included: language, reading and writing, numeric/calculation, limb praxis, visuospatial function, social use of language, emotional function, attention, executive function, and memory. Conclusion. Conceptualizing domains of functional cognition is the first step in developing a computer adaptive measure of functional cognition for stroke. Additional steps include developing, refining, and field-testing items, psychometric analysis, and computer adaptive test programming.

Epilepsy and Language Development: The Continuous Spike-Waves during Slow Sleep Syndrome

BACKGROUND

Continuous spike-waves during slow sleep syndrome (CSWSS) is a rare epileptic syndrome occurring in children, which is characterized by the association of epilepsy, neuropsychological disorders, and abnormal paroxysmal electroencephalographic (EEG) discharges activated by sleep. Language can be affected but, to date, language disorders and their long-term outcome have been documented only rarely.

PURPOSES

Description of language impairment in patients with the CSWSS.

METHODS

We performed a detailed language testing in 10 right-handed children and adolescents with the CSWSS. Their pragmatic performance was compared to that of a control population of 36 children aged 6-10 years.

RESULTS

Patients with CSWSS had lower scores in tests measuring their lexical, morphosyntactic, and pragmatic skills compared to controls. Comprehension remains unaffected. In addition, language impairment was found to be just as severe in patients in remission as those still in an active phase.

CONCLUSIONS

We found severe language impairments in lexical and syntactic skills. The language profile is different from that observed in the Landau-Kleffner syndrome. Moreover patients in remission and those in an active phase of the CSWSS have the same language impairment profiles. This confirms the poor long-term neuropsychological prognosis. Our results raise points about the relationship between epileptic activity and language development. This pilot study underscores the need to assess language, and especially pragmatic skills, and to study long-term outcome in such childhood epileptic syndromes.

Why consider impaired social language usage in a case of corticobasal degeneration?

The purpose of this case study was to examine the integrity of cognitive skills, language usage, and language structure components in a patient with corticobasal degeneration (CBD). CBD is a levadopa-nonresponsive, degenerative neurologic movement disorder that is generally accompanied by cognitive (frontal executive dysfunction, dementia) and linguistic (aphasia) disorders. However, no one has reported on social language usage deficits in cases of CBD. The reported frontal executive dysfunction found in CBD led us to expect social language usage deficits in the present case study. Consistent with the literature, the patient demonstrated motor, cognitive (severe apraxia, frontal executive deficits, dementia), and linguistic deficits (aphasia). However she also demonstrated significantly abnormal social language usage previously unreported in the literature.

The role of the right cerebral hemisphere in processing novel metaphoric expressions taken from poetry: a divided visual field study

Previous research suggests that the right hemisphere (RH) may contribute uniquely to the processing of metaphoric language. However, most studies have focused on familiar metaphoric expressions. The present study used the divided visual field paradigm to examine the role of the right cerebral hemisphere in processing novel metaphoric expressions taken from poetry. In two experiments, participants were presented with four types of word pairs, literal, conventional metaphoric and novel metaphoric expressions and unrelated word pairs, and asked to perform a semantic judgment task. Two different SOAs: 400 and 1100 ms were used. The results of both experiments showed that responses to LVF/RH presented target words were more accurate and faster than responses to RVF/LH target words for novel metaphoric expressions, but not for other types of word pairs. These results support previous research indicating that during word recognition, the RH activates a broader range of related meanings than the LH, including novel, nonsalient meanings. The findings thus suggest that the RH may be critically involved in at least one important component of novel metaphor comprehension, i.e., the integration of the individual meanings of two seemingly unrelated concepts into a meaningful metaphoric expression.

A study of humour and communicative intention following right hemisphere stroke

This research provides further data regarding non-literal language comprehension following right hemisphere damage (RHD). To assess the impact of RHD on the processing of non-literal language, ten participants presenting with RHD and ten matched healthy control participants were administered tasks tapping humour appreciation and pragmatic interpretation of non-literal language. Although the RHD participants exhibited a relatively intact ability to interpret humour from jokes, their use of pragmatic knowledge about interpersonal relationships in discourse was significantly reduced, leading to abnormalities in their understanding of communicative intentions (CI). Results imply that explicitly detailing CI in discourse facilitates RHD participants' comprehension of non-literal language.

Brain correlates of discourse processing: an fMRI investigation of irony and conventional metaphor comprehension

Higher levels of discourse processing evoke patterns of cognition and brain activation that extend beyond the literal comprehension of sentences. We used fMRI to examine brain activation patterns while 16 healthy participants read brief three-sentence stories that concluded with either a literal, metaphoric, or ironic sentence. The fMRI images acquired during the reading of the critical sentence revealed a selective response of the brain to the two types of nonliteral utterances. Metaphoric utterances resulted in significantly higher levels of activation in the left inferior frontal gyrus and in bilateral inferior temporal cortex than the literal and ironic utterances. Ironic statements resulted in significantly higher activation levels than literal statements in the right superior and middle temporal gyri, with metaphoric statements resulting in intermediate levels in these regions. The findings show differential hemispheric sensitivity to these aspects of figurative language, and are relevant to models of the functional cortical architecture of language processing in connected discourse.

Metaphorical vs. literal word meanings: fMRI evidence against a selective role of the right hemisphere

The neural networks associated with processing metaphorical word meanings were investigated in normal adults using fMRI. Subjects listened to sets of three adjectives and decided whether the last two had a similar meaning. One condition required accessing the literal meaning of the middle word (e.g., hot-cold-chilly), whereas the other condition required accessing its nonliteral, or metaphorical, meaning (e.g., hot-cold-unfriendly). Direct comparison of the nonliteral vs. literal condition showed reliable activity only in left prefrontal and temporo-parietal regions. These results argue against a selective role of the right hemisphere (RH) in accessing metaphorical word meanings. In line with a growing literature, these findings suggest that prior reports of greater RH involvement for metaphorical language might reflect the increased complexity of figurative language rather than an RH specialization for understanding metaphors.

Alterações cognitivas, comunicativas e emocionais após lesão hemisférica direita: em busca de uma caracterização da Síndrome do Hemisfério Direito

O conjunto de sinais e sintomas observados após um acometimento neurológico no hemisfério direito pode ser denominado de Síndrome do Hemisfério Direito &– SHD. Esse ensaio teórico tem por objetivo apresentar uma caracterização desse quadro neuropsicológico. A SHD é, então, caracterizada por déficits nas funções cognitivas atenção, percepção, memória, praxias e funções executivas, com a presença de anosognosia, heminegligência sensorial, prosopagnosia, alterações de memória visuo-espacial e de trabalho, dispraxia construtiva e disfunção executiva. Quanto às habilidades comunicativas, a SHD engloba alterações nos componentes discursivo, pragmático-inferencial, léxico-semântico e prosódico. Os déficits de processamento emocional incluem dificuldades de compreensão e produção de emoções a partir de expressões faciais ou emissões vocais e alterações neuropsiquiátricas. Há, no entanto, uma heterogeneidade na sua manifestação. Tendo em vista essa variabilidade de sinais e sintomas, mais estudos de caso e de grupo com indivíduos lesados de hemisfério direito devem ser conduzidos para um melhor entendimento da SHD.

The role of the right hemisphere in processing nonsalient metaphorical meanings: Application of Principal Components Analysis to fMRI data

Some researches indicate that the right hemisphere (RH) has a unique role in comprehending the figurative meaning of metaphors whereas the results of other studies do not support the notion of a selective role for the RH in accessing metaphorical meanings. The present research used fMRI technology to test a theoretical explanation of the above conflicting findings. This theoretical account is derived from the Graded Salience Hypothesis (GSH) [Giora, R. (1997). Understanding figurative and literal language: the Graded Salience Hypothesis. Cognitive Linguistics, 7, 183-206; Giora, R. (2003). On our mind: Salience, context and figurative language. New York: Oxford University Press], according to which the degree of meaning salience, rather than literality or nonliterality primarily affects differences between the LH and RH in linguistic processing. Thus, the GSH predicts a selective RH involvement in comprehension of novel, nonsalient metaphoric meanings and LH involvement in the comprehension of conventional, salient metaphoric meanings. Fifteen normal adults participated in a block designed fMRI experiment that compared the patterns of brain activation induced by processing the meanings of literal, conventional metaphoric, novel metaphoric and unrelated word pairs. The subjects performed a semantic judgment task. We applied the Principal Components Analysis (PCA) technique in order to find different functional networks corresponding to the different stimuli. Our results, obtained from PCA of the fMRI data indicate that the right homologue of Wernicke's area has a special role in processing novel metaphors. We suggest that a unique network, consisting of the right homologue of Wernicke's area, right and left premotor areas, right and left insula and Broca's area, is recruited for the processing of novel metaphors but not for the processing of conventional metaphors.

Narrative comprehension and retelling abilities of children with nonverbal learning disabilities

Nonverbal learning disabilities (NLD) are characterized by weaknesses in narrative discourse. Thirty-three children (M ag e= 11.7 years), 15 girls and 18 boys, listened to stories to evaluate their narrative comprehension and retelling abilities. Children with NLD (n = 11) performed as poorly as children with verbal impairment (n = 10) on all narrative measures. Compared to typical controls (n = 12), the NLD group was poorer in comprehending inferences, but not facts. They included less of the original content than controls in their story retells, and there were strong trends suggesting fewer utterances and less variety in their vocabulary usage. Results are discussed regarding their implications for understanding the neuropsychological profile of NLD.

Thought disorder and nucleus accumbens in childhood: a structural MRI study

Thought disorder has been described as a hallmark feature in both adult and childhood-onset schizophrenia. The nucleus accumbens (NAc) has been repeatedly proposed as a critical station for modulating gating of information flow and processing of information within the thalamocortical circuitry. The aim of the present study was to investigate the relationship of thought disorder measures, which were administered to 12 children with schizophrenia and 15 healthy age-matched controls, and NAc volumes obtained from high-resolution volumetric magnetic resonance imaging analyses. The propensity for specific thought disorder features was significantly related to NAc volumes, despite no statistically significant differences in the NAc volumes of children with schizophrenia and normal children. Smaller left NAc volumes were significantly related to poor on-line revision of linguistic errors in word choice, syntax and reference. On the other hand, underuse of on-line repair of errors in planning and organizing thinking was significantly associated with decreased right NAc volumes. The results of this pilot study suggest that the NAc is implicated in specific thought patterns of childhood. They also suggest that subcortical function in the NAc might reflect hemispheric specialization patterns with left lateralization for revision of linguistic errors and right lateralization for repair strategies involved in the organization of thinking.

Weak coherence, no theory of mind, or executive dysfunction? Solving the puzzle of pragmatic language disorders

Deficits in pragmatic language ability are common to a number of clinical populations, for example, right-hemisphere damage (RHD), Autism and traumatic brain injury (TBI). In these individuals the basic structural components of language may be intact, but the ability to use language to engage socially is impaired. Despite the nature of these difficulties being well documented, exactly what causes these difficulties is less clear. Furthermore, the current status of causal explanations for pragmatic difficulties across these populations is divergent and sometimes contradictory. This paper explores the empirical validity of three theories that attempt to explain pragmatic language impairment. It is recommended that a new, more convergent approach to investigating the causes of pragmatic language disability be adopted.

Making sense during conversation: an fMRI study

Although language is thought of as a left hemisphere function, there is increasing evidence that the right hemisphere contributes to language processing by identifying the theme of spoken and written language. Using fMRI, we examined the role played by the right and left hemispheres in making sense of a conversation. When this process involves implicit appraisal of changes in the conversation's topic, the neural network has a right hemisphere bias and includes Broca's and Wernicke's areas, their right hemisphere homologues, right dorsolateral prefrontal cortex, and the cerebellum. When making sense of conversation involves appraisal of the conversation's reasoning, however, the network includes Broca's and Wernicke's areas. Thus, right and left hemisphere systems contribute uniquely to the linguistic skills involved in making sense of a conversation.