Cognitive Impairment After Ischemic and Hemorrhagic Stroke: A Scientific Statement From the American Heart Association/American Stroke Association.

PURPOSE: Cognitive impairment is a common consequence of stroke and has direct implications for poststroke functioning and quality of life, including the ability to maintain a job, live independently, sustain interpersonal relationships, and drive a vehicle. In this scientific statement, we critically appraise the literature on the prevalence, diagnosis, and management of poststroke cognitive impairment (PSCI) and provide a framework for clinical care while highlighting gaps that merit further study. METHODS: We performed a scoping literature review of randomized controlled clinical trials, prospective and retrospective cohort studies, case-control studies, clinical guidelines, review articles, and editorials on the incidence and prevalence, natural history, diagnosis, and management of PSCI. Scoping reviews determine the scope of a body of literature on a given topic to indicate the volume of literature and the studies currently available and provide an overview of its focus. RESULTS: PSCI is common after stroke, especially in the first year, and ranges from mild to severe. Although cognitive impairment is reversible in some cases early after stroke, up to one-third of individuals with stroke develop dementia within 5 years. The pathophysiology is not yet fully elucidated but is likely attributable to an acute stroke precipitating a series of pathological events, often in the setting of preexisting microvascular and neurodegenerative changes. Screening for associated comorbidities and interdisciplinary management are integral components of the care of individuals with PSCI. There is a need for prospective studies evaluating the individual trajectory of PSCI and the role of the acute vascular event in the predisposition for Alzheimer disease and related dementias, as well as high-quality, randomized clinical trials focused on PSCI management.

Apragmatism: The renewal of a label for communication disorders associated with right hemisphere brain damage.

BACKGROUND: Right hemisphere communication disorders are neither consistently labelled nor adequately defined. Labels associated with right hemisphere brain damage (RHD) are broad and fail to capture the essence of communication challenges needed for stroke-related service provisions. Determination of rehabilitation needs and best-practice guidelines for the education, management and functional improvement of communication disorders after RHD are all predicated on an apt diagnostic label and disorder characteristics. AIMS: In this paper apragmatism is proposed as a potential communication-specific diagnostic label for the impairments in communication that occur after RHD. In particular, the researchers aimed: (1) to establish an operational definition of apragmatism; and (2) to describe the linguistic, paralinguistic and extralinguistic communication deficits under the umbrella term apragmatism. METHODS & PROCEDURES: An international collaborative of researchers with expertise in RHD followed a multilevel approach to consider the utility of apragmatism as a diagnostic label. Adopting the relational approach to concept mapping, the researchers engaged in a series of group meetings to complete four levels of mapping: (1) identify and review, (2) define, (3) expert discussion and (4) label determination. MAIN CONTRIBUTION: Apragmatism was established as a suitable diagnostic label for the impairments in communication associated with RHD. The paper offers an operational definition and description of the linguistic, paralinguistic and extralinguistic features of apragmatism through evidence summaries and examples from people with RHD retrieved from the RHDBank. CONCLUSIONS & IMPLICATIONS: The adoption of the term apragmatism offers an opportunity to capture the hallmark of RHD communication deficits. The use of the term is recommended when referencing the pragmatic language impairments in this population. Apragmatism, which may co-occur with or be exacerbated by cognitive impairments, can interfere with the ability to interpret and convey intended meaning and impact the lives of right hemisphere stroke survivors and their families. WHAT THIS PAPER ADDS: What is already known on the subject RHD results in a heterogeneous group of deficits that range in cognitive-communicative complexity. Many of the deficits are subsumed under pragmatics. For example, adults with RHD may demonstrate tangential or verbose communication, insensitivity to others' needs and feelings, prosodic changes, minimal gesture use and facial expression, and more. While descriptions of pragmatic impairments pervade the literature, there is no consistently used diagnostic label. The clinical consequences of this absence include difficulty with inter- and intra-disciplinary communication about these patients, difficulty consolidating findings across research studies, and challenges in communicating about these pragmatic changes with patients, families and other stakeholders. What this paper adds to existing knowledge The term apragmatism is proposed as a diagnostic label to consistently describe pragmatic communication changes after RHD. Apragmatism is characterized using three components of pragmatics: linguistic, paralinguistic and extralinguistic. Descriptions and examples of these three components are provided with supplemental transcripts retrieved from the RHDBank. What are the potential or actual clinical implications of this work? Adoption of the term apragmatism by speech and language therapists and other medical and rehabilitation professionals has the potential to provide consistency in describing the abilities and challenges experienced by people following a right hemisphere stroke. Such improvements may help drive the development of evidence-based assessments and treatments for this population.

Aprosodia Following Focal Brain Damage: What's Right and What's Left?

PURPOSE: Hemispheric specialization for the comprehension and expression of linguistic and emotional prosody is typically attributed to the right hemisphere. This study used techniques adapted from meta-analysis to critically examine the strength of existing evidence for hemispheric lateralization of prosody following brain damage. METHOD: Twenty-one databases were searched for articles published from 1970 to 2020 addressing differences in prosody performance between groups defined by right hemisphere damage and left hemisphere damage. Hedges's g effect sizes were calculated for all possible prosody comparisons. Primary analyses summarize effects for four types: linguistic production, linguistic comprehension, emotion comprehension, and emotion production. Within each primary analysis, Hedges's g values were averaged across comparisons (usually from a single article) based on the same sample of individuals. Secondary analyses explore more specific classifications of comparisons. RESULTS: Out of the 113 articles investigating comprehension and production of emotional and linguistic prosody, 62 were deemed appropriate for data extraction, but only 21 met inclusion criteria, passed quality reviews, and provided sufficient information for analysis. Evidence from this review illustrates the heterogeneity of research methods and results from studies that have investigated aprosodia. This review provides inconsistent support for selective contribution of the two cerebral hemispheres to prosody comprehension and production; however, the strongest finding suggests that right hemisphere lesions disrupt emotional prosody comprehension more than left hemisphere lesions. CONCLUSION: This review highlights the impoverished nature of the existing literature; offers suggestions for future research; and highlights relevant clinical implications for the prognostication, evaluation, and treatment of aprosodia. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.20334987.

The Company Prosodic Deficits Keep Following Right Hemisphere Stroke: A Systematic Review.

OBJECTIVES: The aim of this systematic review was to identify the presence and nature of relationships between specific forms of aprosodia (i.e., expressive and receptive emotional and linguistic prosodic deficits) and other cognitive-communication deficits and disorders in individuals with right hemisphere damage (RHD) due to stroke. METHODS: One hundred and ninety articles from 1970 to February 2020 investigating receptive and expressive prosody in patients with relatively focal right hemisphere brain damage were identified via database searches. RESULTS: Fourteen articles were identified that met inclusion criteria, passed quality reviews, and included sufficient information about prosody and potential co-occurring deficits. Twelve articles investigated receptive emotional aprosodia, and two articles investigated receptive linguistic aprosodia. Across the included studies, receptive emotional prosody was not systematically associated with hemispatial neglect, but did co-occur with deficits in emotional facial recognition, interpersonal interactions, or emotional semantics. Receptive linguistic processing was reported to co-occur with amusia and hemispatial neglect. No studies were found that investigated the co-occurrence of expressive emotional or linguistic prosodic deficits with other cognitive-communication impairments. CONCLUSIONS: This systematic review revealed significant gaps in the research literature regarding the co-occurrence of common right hemisphere disorders with prosodic deficits. More rigorous empirical inquiry is required to identify specific patient profiles based on clusters of deficits associated with right hemisphere stroke. Future research may determine whether the co-occurrences identified are due to shared cognitive-linguistic processes, and may inform the development of evidence-based assessment and treatment recommendations for individuals with cognitive-communication deficits subsequent to RHD.

Making Sense of Right Hemisphere Discourse Using RHDBank.

PURPOSE: Right hemisphere brain damage (RHD) commonly causes pragmatic language disorders that are apparent in discourse production. Specific characteristics and approaches to assessment, diagnosis, and treatment of these disorders are not well-defined. RHDBank, a shared database of multimedia interactions for the study of communication using discourse, was created to address these gaps. The database, materials, and related analysis programs are free resources to clinicians, researchers, educators, and students. METHOD: A standard discourse protocol was developed to elicit multiple types of discourse: free speech, conversation, picture description, storytelling, procedural discourse, and question-asking. Testing included measures of cognition, unilateral neglect, and communicative participation. Language samples were video-recorded and transcribed in CHAT format. Currently, the database includes 24 adults with RHD and 24 controls. RESULTS: Illustrative analyses show how RHDBank can facilitate research using micro- and macrolinguistic discourse analysis techniques both within this population and across populations. Educational resources, such as the Grand Rounds tutorial, were developed using case studies from the database. CONCLUSIONS: RHDBank is a shared database of resources that can facilitate educational and research efforts to address the gaps in knowledge about RHD communication and improve the clinical management of individuals with RHD.

Speech-Language Pathology Practices for Adults With Right Hemisphere Stroke: What Are We Missing?

Purpose Limited evidence exists to guide the assessment and treatment of cognitive-communication disorders associated with right hemisphere stroke. The purpose of this study was to obtain information about speech-language pathologists' (SLPs') clinical practices and decision making for this population to understand what practices are being used and identify gaps in clinical practice. Method A survey was distributed via online ASHA Communities for the Special Interest Groups and other social media platforms. Respondents included 143 SLPs from across the United States representing 3-50 years of experience and a wide range of practice settings. Survey questions probed assessment practices including how tests are selected, what tests are used to diagnose specific deficits, and how confident SLPs were in their diagnoses. Treatment decisions were queried for a small set of disorders. Results SLPs routinely assess cognitive disorders using standardized tests. Communication disorders are less likely to be formally assessed. Three core right cerebral hemisphere deficits-anosognosia, aprosodia, and pragmatic deficits-are either not assessed or assessed only through observation by 80% of SLPs. Evidence-based treatments are commonly used for disorders of attention, awareness, and aprosodia. Conclusion Communication disorders are less likely to be formally assessed than cognitive disorders, creating a critical gap in care that cannot be filled by other allied health professionals. Suggestions for free or low-cost resources for evaluating pragmatics, prosody, and awareness are provided to aid SLPs in filling this gap. Supplemental Material https://doi.org/10.23641/asha.12159597.

Contextual Constraint Treatment for coarse coding deficit in adults with right hemisphere brain damage: generalisation to narrative discourse comprehension.

Coarse coding is the activation of broad semantic fields that can include multiple word meanings and a variety of features, including those peripheral to a word's core meaning. It is a partially domain-general process related to general discourse comprehension and contributes to both literal and non-literal language processing. Adults with damage to the right cerebral hemisphere (RHD) and a coarse coding deficit are particularly slow to activate features of words that are relatively distant or peripheral. This manuscript reports a pre-efficacy study of Contextual Constraint Treatment (CCT), a novel, implicit treatment designed to increase the efficiency of coarse coding with the goal of improving narrative comprehension and other language performance that relies on coarse coding. Participants were four adults with RHD. The study used a single-subject controlled experimental design across subjects and behaviours. The treatment involved pre-stimulation, using a hierarchy of strong and moderately biased contexts, to prime the intended distantly related features of critical stimulus words. Three of the four participants exhibited gains in auditory narrative discourse comprehension, the primary outcome measure. All participants exhibited generalisation to untreated items. No strong generalisation to processing non-literal language was evident. The results indicate that CCT yields both improved efficiency of the coarse coding process and generalisation to narrative comprehension.

Generalization of a Novel, Implicit Treatment for Coarse Coding Deficit in Right Hemisphere Brain Damage: A Single Subject Experiment.

BACKGROUND: This manuscript reports generalization effects of Contextual Constraint Treatment for an adult with right hemisphere brain damage (RHD). Contextual Constraint Treatment is designed to stimulate inefficient language comprehension processes implicitly, by providing linguistic context to prime, or constrain, the intended interpretations of treatment stimuli. The study participant had a coarse coding deficit, defined as delayed mental activation of particularly distant semantic features of words (e.g., rotten as a feature of "apple"). Treatment effects were expected to generalize to auditory comprehension of narrative discourse, and perhaps to figurative language interpretation, because coarse coding has been hypothesized and/or demonstrated to support these abilities. AIMS: This treatment study aimed to induce generalization of Contextual Constraint Treatment in an adult with RHD with inefficient coarse coding. METHODS #ENTITYSTARTX00026; PROCEDURES: The participant in this study was a 75 year old man with RHD and a coarse coding deficit. A single subject experimental design across behaviors (stimulus lists) was used to document performance in baseline, treatment, and follow-up phases. Treatment consisted of providing brief, spoken context sentences to prestimulate, or constrain, intended interpretations of stimulus items. The participant made no explicit associations or metalinguistic judgments about the constraint sentences or stimulus words; rather, these contexts served only as implicit primes. Probe tasks were adapted from prior work on coarse coding in RHD. The dependent measure was the percentage of responses that met predetermined response time criteria. There were two levels of contextual constraint, Strong and Moderate. Treatment for each item began with the provision of the Strong constraint context, to minimize the production or reinforcement of erroneous or exceedingly slow responses. Generalization was assessed to a well-standardized measure of narrative discourse comprehension and to several metalinguistic tasks of figurative language interpretation. OUTCOMES #ENTITYSTARTX00026; RESULTS: Treatment-contingent gains, associated with respectable effect sizes, were evident after a brief period of treatment on one stimulus list. Generalization occurred to untrained items, suggesting that the treatment was facilitating the underlying coarse coding process. Most importantly, generalization was evident to narrative comprehension performance, for both overall accuracy and accuracy answering questions about implied information, and all of these gains maintained through three follow-up sessions. CONCLUSIONS: Though the results are still preliminary, this single-subject experimental design documents the potential for meaningful gains from a novel treatment that implicitly targets an underlying language comprehension process in an adult with RHD.

Inferencing processes after right hemisphere brain damage: effects of contextual bias.

PURPOSE: Comprehension deficits associated with right hemisphere brain damage (RHD) have been attributed to an inability to use context, but there is little direct evidence to support the claim. This study evaluated the effect of varying contextual bias on predictive inferencing by adults with RHD. METHOD: Fourteen adults with no brain damage (NBD) and 14 with RHD read stories constructed with either high predictability or low predictability of a specific outcome. Reading time for a sentence that disconfirmed the target outcome was measured and compared with a control story context. RESULTS: Adults with RHD evidenced activation of predictive inferences only for highly predictive conditions, whereas NBD adults generated inferences in both high- and low-predictability stories. Adults with RHD were more likely than those with NBD to require additional time to integrate inferences in high-predictability conditions. The latter finding was related to working memory for the RHD group. Results are interpreted in light of previous findings obtained using the same stimuli. CONCLUSIONS: RHD does not abolish the ability to use context. Evidence of predictive inferencing is influenced by task and strength of inference activation. Treatment considerations and cautions regarding interpreting results from one methodology are discussed.

Inferencing processes after right hemisphere brain damage: maintenance of inferences.

PURPOSE: This study was designed to replicate and extend a previous study of inferencing in which some adults with right hemisphere damage (RHD) generated but did not maintain predictive inferences over time (M. Lehman-Blake & C. Tompkins, 2001). Two hypotheses were tested: (a) inferences were deactivated, and (b) selection of previously generated inferences was slowed and not measurable with the original stimuli. Existing literature did not support one hypothesis over the other. METHOD: Fourteen adults with RHD and 14 with no brain damage (NBD) participated in this mixed-design study. Participants read short narratives that suggested a predictive inference. Reading times were obtained to assess inference generation, maintenance, and integration. RESULTS: The majority of participants evidenced generation and maintenance of inferences. For the few who did not maintain inferences, participants with NBD always deactivated the inferences, whereas those with RHD demonstrated either deactivation or slowed selection. Adults with RHD were more likely to exhibit slowing in inference generation and integration. CONCLUSIONS: The results for inference maintenance differ from the original study in that most participants with RHD maintained inferences. Deactivation appeared in both groups, whereas slowed selection appeared to be an aberrant process related to RHD. Future work is needed to tease out the relationships between comprehension, working memory, and inferencing processes.

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.