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Journal of Communication Disorders 2023Autoimmune neurological diseases (ANDs) are a specific type of autoimmune disease that affect cells within the central and peripheral nervous system. ANDs trigger... (Review)
Review
INTRODUCTION
Autoimmune neurological diseases (ANDs) are a specific type of autoimmune disease that affect cells within the central and peripheral nervous system. ANDs trigger various physical/neuropsychiatric symptoms. However, language impairments in people with ANDs are not well characterized. Here we aimed to determine the kinds of language impairment that most commonly emerge in 10 ANDs, the characteristics of the patients (demographic, neurological damage), and the assessment methods used.
METHODS
We followed the PRISMA Extension for Scoping Reviews (PRISMA-ScR). PubMed and Google Scholar were searched. We used a list of search terms containing 10 types of ANDs (e.g., multiple sclerosis, acute disseminated encephalomyelitis) in combination with the terms aphasia, dysphasia, fluency, language, listening, morphology, phonology, pragmatics, reading, semantics, speaking, syntax, writing. The reference lists and citations of the relevant papers were also investigated. The type of AND, patient characteristics, neurological damage and examination technique, language tests administered, and main findings were noted for each study meeting the inclusion criteria.
RESULTS
We found 171 studies meeting our inclusion criteria. These comprised group studies and case studies. Language impairments differed largely among types of ANDs. Neurological findings were mentioned in most of the papers, but specific language tests were rarely used.
CONCLUSIONS
Language symptoms in people with ANDs are commonly reported. These are often not full descriptions or only focus on specific time points in the course of the disease. Future research needs to assess specific language functions in people with ANDs and relate their language impairments to brain damage at different stages of disease evolution.
Topics: Humans; Aphasia; Linguistics; Language Tests; Language Development Disorders
PubMed: 37717472
DOI: 10.1016/j.jcomdis.2023.106368 -
Brain Sciences Apr 2024Here, we review the literature on neurotypical individuals and individuals with post-stroke aphasia showing that right-hemisphere regions homologous to language network... (Review)
Review
Here, we review the literature on neurotypical individuals and individuals with post-stroke aphasia showing that right-hemisphere regions homologous to language network and other regions, like the right cerebellum, are activated in language tasks and support language even in healthy people. We propose that language recovery in post-stroke aphasia occurs largely by potentiating the right hemisphere network homologous to the language network and other networks that previously supported language to a lesser degree and by modulating connection strength between nodes of the right-hemisphere language network and undamaged nodes of the left-hemisphere language network. Based on this premise (supported by evidence we review), we propose that interventions should be aimed at potentiating the right-hemisphere language network through Hebbian learning or by augmenting connections between network nodes through neuroplasticity, such as non-invasive brain stimulation and perhaps modulation of neurotransmitters involved in neuroplasticity. We review aphasia treatment studies that have taken this approach. We conclude that further aphasia rehabilitation with this aim is justified.
PubMed: 38790398
DOI: 10.3390/brainsci14050419 -
Stroke Aug 2023Large-scale clinical trials and meta-analyses have determined neurobiological and linguistic predictors of recovery from aphasia, while more recent work is opening the... (Review)
Review
Large-scale clinical trials and meta-analyses have determined neurobiological and linguistic predictors of recovery from aphasia, while more recent work is opening the field to factors of efficacy previously established in psychiatry-and little known in neurology. To map this evolving area of research, the present essay explores key factors of efficacy in psychotherapy as potential predictors of recovery from aphasia. In particular, the essay addresses (1) working alliance, including consensus between patient and therapist on treatment goals and tasks alongside interpersonal bonds, as well as (2) focus on resources rather than deficits in language performance. Finally, the essay outlines why research on impaired communication ability may help advance and complement existing methods in psychotherapy.
Topics: Humans; Aphasia; Psychotherapy; Language; Allied Health Personnel
PubMed: 37264908
DOI: 10.1161/STROKEAHA.123.043498 -
American Journal of Speech-language... Oct 2023This study aimed to (a) compare physiological arousal and attentiveness during a confrontational naming task between participants with aphasia and a control group across...
PURPOSE
This study aimed to (a) compare physiological arousal and attentiveness during a confrontational naming task between participants with aphasia and a control group across four conditions that varied according to emotionality of presented stimuli and (b) explore relationships among physiological arousal, attentiveness, perceived arousal, and naming performance. We hypothesized that participants with aphasia would show lower levels of arousal and attentiveness than control participants and that emotional conditions would lead to increased physiological arousal and attentiveness.
METHOD
Eight participants with aphasia and 15 control participants completed a confrontational naming task under positive, negative, and neutral conditions and rated their perceived arousal after each. Electrophysiological recordings were taken during the entire experiment to obtain measures of heart rate (HR), HR variability, and skin conductance (SC). Videos of confrontational naming trials were rated based on visual signs of participant attentiveness during each trial.
RESULTS
Statistically significant group differences were found for HR, SC, and attentiveness ratings, but no differences were found in these measures among conditions. Correlational analyses revealed statistically significant relationships between attentiveness and response time, HR, and naming accuracy. Significant correlations were also found for HR and naming accuracy as well as perceived arousal and naming accuracy.
CONCLUSIONS
Findings suggest that decreased physiological arousal or attentiveness may contribute to naming deficits for people with aphasia (PWA). Assisting PWA to fully attend to and engage in therapy tasks may be important for accurate assessment of language functions and for achieving optimal benefit in treatment.
Topics: Humans; Aphasia; Language; Attention; Emotions; Arousal
PubMed: 37343542
DOI: 10.1044/2023_AJSLP-22-00305 -
Child Neuropsychology : a Journal on... Nov 2023Aphasia has a great impact on children's lives, with stroke being its most common and studied etiology. However, our knowledge about this disorder is limited, the... (Review)
Review
Aphasia has a great impact on children's lives, with stroke being its most common and studied etiology. However, our knowledge about this disorder is limited, the studies on this topic are sparse, and a consensus regarding its definition is lacking. In particular, the interpretation of this condition varied over time: from the rigid description of the so-called "standard doctrine" to the adoption of adult models for post-stroke aphasia. Therefore, this review provides a critical overview of childhood aphasia after stroke, focusing on its epidemiology, definition, diagnosis, and clinical manifestation. The scoping review approach was adopted, following PRISMA-ScR guidelines. PubMed, Web of Science, and PsycInfo databases were searched for related peer-review papers in English. Forty-six records were identified; the majority were single cases and case series, only a few were reviews and observational studies. Epidemiologic data are scarce; a few studies report that aphasia affects about one-third of children post-stroke. Despite terminological differences, there is an overall agreement on the definition of post-stroke aphasia in children as a language disorder acquired after the age of two. Approaches for the diagnosis and evaluation vary widely, including both assessments for developmental language disorders and tests for aphasia in adults. The clinical manifestations described in children are numerous and varied, similar to those found in adults, in contrast with the "standard doctrine." This review highlights the need for further studies to improve the knowledge of this condition, develop validated and specific assessment tools, and standardize clinical management.
PubMed: 36548197
DOI: 10.1080/09297049.2022.2156992 -
Brain : a Journal of Neurology Oct 2023Successful communication in daily life depends on accurate decoding of speech signals that are acoustically degraded by challenging listening conditions. This process...
Successful communication in daily life depends on accurate decoding of speech signals that are acoustically degraded by challenging listening conditions. This process presents the brain with a demanding computational task that is vulnerable to neurodegenerative pathologies. However, despite recent intense interest in the link between hearing impairment and dementia, comprehension of acoustically degraded speech in these diseases has been little studied. Here we addressed this issue in a cohort of 19 patients with typical Alzheimer's disease and 30 patients representing the three canonical syndromes of primary progressive aphasia (non-fluent/agrammatic variant primary progressive aphasia; semantic variant primary progressive aphasia; logopenic variant primary progressive aphasia), compared to 25 healthy age-matched controls. As a paradigm for the acoustically degraded speech signals of daily life, we used noise-vocoding: synthetic division of the speech signal into frequency channels constituted from amplitude-modulated white noise, such that fewer channels convey less spectrotemporal detail thereby reducing intelligibility. We investigated the impact of noise-vocoding on recognition of spoken three-digit numbers and used psychometric modelling to ascertain the threshold number of noise-vocoding channels required for 50% intelligibility by each participant. Associations of noise-vocoded speech intelligibility threshold with general demographic, clinical and neuropsychological characteristics and regional grey matter volume (defined by voxel-based morphometry of patients' brain images) were also assessed. Mean noise-vocoded speech intelligibility threshold was significantly higher in all patient groups than healthy controls, and significantly higher in Alzheimer's disease and logopenic variant primary progressive aphasia than semantic variant primary progressive aphasia (all P < 0.05). In a receiver operating characteristic analysis, vocoded intelligibility threshold discriminated Alzheimer's disease, non-fluent variant and logopenic variant primary progressive aphasia patients very well from healthy controls. Further, this central hearing measure correlated with overall disease severity but not with peripheral hearing or clear speech perception. Neuroanatomically, after correcting for multiple voxel-wise comparisons in predefined regions of interest, impaired noise-vocoded speech comprehension across syndromes was significantly associated (P < 0.05) with atrophy of left planum temporale, angular gyrus and anterior cingulate gyrus: a cortical network that has previously been widely implicated in processing degraded speech signals. Our findings suggest that the comprehension of acoustically altered speech captures an auditory brain process relevant to daily hearing and communication in major dementia syndromes, with novel diagnostic and therapeutic implications.
Topics: Humans; Alzheimer Disease; Comprehension; Speech; Brain; Aphasia; Aphasia, Primary Progressive; Neuropsychological Tests
PubMed: 37184986
DOI: 10.1093/brain/awad163 -
Brain Structure & Function Dec 2023Aphasia is a speech-language impairment commonly caused by damage to the left hemisphere. The neural mechanisms that underpin different types of aphasia and their...
INTRODUCTION
Aphasia is a speech-language impairment commonly caused by damage to the left hemisphere. The neural mechanisms that underpin different types of aphasia and their symptoms are still not fully understood. This study aims to identify differences in resting-state functional connectivity between anomic and Broca's aphasia measured through resting-state functional magnetic resonance imaging (rs-fMRI).
METHODS
We used the network-based statistic (NBS) method, as well as voxel- and connectome-based lesion symptom mapping (V-, CLSM), to identify distinct neural correlates of the anomic and Broca's groups. To control for lesion effect, we included lesion volume as a covariate in both the NBS method and LSM.
RESULTS
NBS identified a subnetwork located in the dorsal language stream bilaterally, including supramarginal gyrus, primary sensory, motor, and auditory cortices, and insula. The connections in the subnetwork were weaker in the Broca's group than the anomic group. The properties of the subnetwork were examined through complex network measures, which indicated that regions in right inferior frontal sulcus, right paracentral lobule, and bilateral superior temporal gyrus exhibit intensive interaction. Left superior temporal gyrus, right postcentral gyrus, and left supramarginal gyrus play an important role in information flow and overall communication efficiency. Disruption of this network underlies the constellation of symptoms associated with Broca's aphasia. Whole-brain CLSM did not detect any significant connections, suggesting an advantage of NBS when thousands of connections are considered. However, CLSM identified connections that differentiated Broca's from anomic aphasia when analysis was restricted to a hypothesized network of interest.
DISCUSSION
We identified novel signatures of resting-state brain network differences between groups of individuals with anomic and Broca's aphasia. We identified a subnetwork of connections that statistically differentiated the resting-state brain networks of the two groups, in comparison with standard CLSM results that yielded isolated connections. Network-level analyses are useful tools for the investigation of the neural correlates of language deficits post-stroke.
PubMed: 38160205
DOI: 10.1007/s00429-023-02738-4 -
Disability and Rehabilitation Oct 2023Aphasia is an acquired language impairment that commonly results from stroke. Non-invasive brain stimulation (NIBS) might accelerate aphasia recovery trajectories and... (Review)
Review
PURPOSE
Aphasia is an acquired language impairment that commonly results from stroke. Non-invasive brain stimulation (NIBS) might accelerate aphasia recovery trajectories and has seen mounting popularity in recent aphasia rehabilitation research. The present review aimed to: (1) summarise all existing literature on NIBS as a post-stroke aphasia treatment; and (2) provide recommendations for future NIBS-aphasia research.
MATERIALS AND METHODS
Databases for published and grey literature were searched using scoping review methodology. 278 journal articles, conference abstracts/posters, and books, and 38 items of grey literature, were included for analysis.
RESULTS
Quantitative analysis revealed that ipsilesional anodal transcranial direct current stimulation and contralesional 1-Hz repetitive transcranial magnetic stimulation were the most widely used forms of NIBS, while qualitative analysis identified four key themes including: the roles of the hemispheres in aphasia recovery and their relationship with NIBS; heterogeneity of individuals but homogeneity of subpopulations; individualisation of stimulation parameters; and much remains under-explored in the NIBS-aphasia literature.
CONCLUSIONS
Taken together, these results highlighted systemic challenges across the field such as small sample sizes, inter-individual variability, lack of protocol optimisation/standardisation, and inadequate focus on aphasiology. Four key recommendations are outlined herein to guide future research and refine NIBS methods for post-stroke aphasia treatment.
PubMed: 37828899
DOI: 10.1080/09638288.2023.2259299 -
Indian Journal of Critical Care... Dec 2023Krishnan A. Author Response. Indian J Crit Care Med 2023;27(12):945-946.
Krishnan A. Author Response. Indian J Crit Care Med 2023;27(12):945-946.
PubMed: 38074969
DOI: 10.5005/jp-journals-10071-24573 -
Expert Review of Neurotherapeutics Mar 2024Aphasia is a communication disorder resulting from stroke and/or neurodegenerative conditions which involve the left cerebral hemisphere. It is a debilitating disorder...
INTRODUCTION
Aphasia is a communication disorder resulting from stroke and/or neurodegenerative conditions which involve the left cerebral hemisphere. It is a debilitating disorder affecting a person's ability to speak, understand, read, and write. Its impact on daily life necessitates therapeutic strategies to aid patients with aphasia.
AREAS COVERED
In this special report, the authors speculate whether current pharmacotherapeutic strategies are effective in treating aphasia. The authors look at aphasia caused by different conditions and how this could impact therapy before providing the reader with their expert perspectives. The aim of this paper is for the reader to gain a clearer understanding of the efficacy of the current pharmacotherapeutic treatment paradigms as well as potential future developments.
EXPERT OPINION
The exploration of pharmacotherapy for aphasia in vascular brain disorders and neurodegenerative diseases has received much attention in recent years with various therapeutic strategies having been put forward. In terms of whether pharmacotherapy is effective for the treatment of aphasia, there is still no clear-cut answer. Further research is needed with more studies requiring a greater emphasis on language and communication deficits. Biomarkers may also help clinicians provide their patients with a more personalized treatment plan.
Topics: Humans; Aphasia; Stroke; Brain; Stroke Rehabilitation
PubMed: 38323346
DOI: 10.1080/14737175.2024.2313557