-
Current Neurology and Neuroscience... Dec 2023Stroke remains a leading disabling condition, and many survivors have permanent disability despite acute stroke treatment and subsequent standard-of-care rehabilitation... (Meta-Analysis)
Meta-Analysis Review
PURPOSE OF REVIEW
Stroke remains a leading disabling condition, and many survivors have permanent disability despite acute stroke treatment and subsequent standard-of-care rehabilitation therapies. Adjunctive neuromodulation is an emerging frontier in the field of stroke recovery. In this narrative review, we aim to highlight and summarize various neuromodulation techniques currently being investigated to enhance recovery and reduce impairment in patients with stroke.
RECENT FINDINGS
For motor recovery, repetitive transcranial magnetic simulation (rTMS) and direct current stimulation (tDCS) have shown promising results in many smaller-scale trials. Still, their efficacy has yet to be proven in large-scale pivotal trials. A promising large-scale study investigating higher dose tDCS combined with constraint movement therapy to enhance motor recovery is currently underway. MRI-guided tDCS studies in subacute and chronic post-stroke aphasia showed promising benefits for picture-naming recovery. rTMS, particularly inhibitory stimulation over the contralesional homolog, could represent a pathway forward in post-stroke motor recovery in the setting of a well-designed and adequately powered clinical trial. Recently evidenced-based guideline actually supported Level A (definite efficacy) for the use of low-frequency rTMS of the primary motor cortex for hand motor recovery in the post-acute stage of stroke based on the meta-analysis result. Adjunctive vagal nerve stimulation has recently received FDA approval to enhance upper limb motor recovery in chronic ischemic stroke with moderate impairment, and progress has been made to implement it in real-world practice. Despite a few small and large-scale studies in epidural stimulation (EDS), further research on the utilization of EDS in post-stroke recovery is needed. Deep brain stimulation or stent-based neuromodulation has yet to be further tested regarding safety and efficacy. Adjunctive neuromodulation to rehabilitation therapy is a promising avenue for promoting post-stroke recovery and decreasing the overall burden of disability. The pipeline for neuromodulation technology remains strong as they span from the preclinical stage to the post-market stage. We are optimistic to see that more neuromodulation tools will be available to stroke survivors in the not-to-distant future.
Topics: Humans; Transcranial Magnetic Stimulation; Stroke Rehabilitation; Stroke; Transcranial Direct Current Stimulation; Upper Extremity; Recovery of Function
PubMed: 38015351
DOI: 10.1007/s11910-023-01319-6 -
Journal of Speech, Language, and... Jun 2024This study explored the use of an automated language analysis tool, FLUCALC, for measuring fluency in aphasia. The purpose was to determine whether CLAN's FLUCALC...
PURPOSE
This study explored the use of an automated language analysis tool, FLUCALC, for measuring fluency in aphasia. The purpose was to determine whether CLAN's FLUCALC command could produce efficient, objective outcome measures for salient aspects of fluency in aphasia.
METHOD
The FLUCALC command was used on CHAT transcripts of Cinderella stories from people with aphasia (PWA; = 281) and controls ( = 257) in the AphasiaBank database.
RESULTS
PWA produced significantly fewer total words, fewer words per minute, more pausing, more repetitions, more revisions, and more phonological fragments than controls, with only one exception: The Wernicke's group was similar to the control group in percentage of filled pauses. Individuals with Broca's aphasia had significantly longer inter-utterance pauses and fewer total words than all other aphasia groups. Both the Broca's and conduction aphasia groups had higher percentages of phrase repetitions than the NABW (NotAphasicByWAB) group. The conduction aphasia group also had a higher percentage of phrase revisions than the NABW and the anomic aphasia groups. Principal components analysis revealed two principal components that accounted for around 60% of the variance and related to quantity of output, rate of speech, and quality of output. The Gaussian mixture models showed that the participants clustered in three groups, which corresponded predominantly to the controls, the nonfluent aphasia group, and the remaining aphasia groups (all classically fluent aphasia types).
CONCLUSIONS
FLUCALC is an efficient way to measure objective fluency behaviors in language samples in aphasia. Automated analyses of objective fluency behaviors on large samples of adults with and without aphasia can produce measures that can be used by researchers and clinicians to better understand and track salient aspects of fluency in aphasia.
SUPPLEMENTAL MATERIAL
https://doi.org/10.23641/asha.25979863.
PubMed: 38875483
DOI: 10.1044/2024_JSLHR-23-00659 -
Brain : a Journal of Neurology Apr 2024It is debated whether primary progressive apraxia of speech (PPAOS) and progressive agrammatic aphasia (PAA) belong to the same clinical spectrum, traditionally termed...
It is debated whether primary progressive apraxia of speech (PPAOS) and progressive agrammatic aphasia (PAA) belong to the same clinical spectrum, traditionally termed non-fluent/agrammatic variant primary progressive aphasia (nfvPPA), or exist as two completely distinct syndromic entities with specific pathologic/prognostic correlates. We analysed speech, language and disease severity features in a comprehensive cohort of patients with progressive motor speech impairment and/or agrammatism to ascertain evidence of naturally occurring, clinically meaningful non-overlapping syndromic entities (e.g. PPAOS and PAA) in our data. We also assessed if data-driven latent clinical dimensions with aetiologic/prognostic value could be identified. We included 98 participants, 43 of whom had an autopsy-confirmed neuropathological diagnosis. Speech pathologists assessed motor speech features indicative of dysarthria and apraxia of speech (AOS). Quantitative expressive/receptive agrammatism measures were obtained and compared with healthy controls. Baseline and longitudinal disease severity was evaluated using the Clinical Dementia Rating Sum of Boxes (CDR-SB). We investigated the data's clustering tendency and cluster stability to form robust symptom clusters and employed principal component analysis to extract data-driven latent clinical dimensions (LCD). The longitudinal CDR-SB change was estimated using linear mixed-effects models. Of the participants included in this study, 93 conformed to previously reported clinical profiles (75 with AOS and agrammatism, 12 PPAOS and six PAA). The remaining five participants were characterized by non-fluent speech, executive dysfunction and dysarthria without apraxia of speech or frank agrammatism. No baseline clinical features differentiated between frontotemporal lobar degeneration neuropathological subgroups. The Hopkins statistic demonstrated a low cluster tendency in the entire sample (0.45 with values near 0.5 indicating random data). Cluster stability analyses showed that only two robust subgroups (differing in agrammatism, executive dysfunction and overall disease severity) could be identified. Three data-driven components accounted for 71% of the variance [(i) severity-agrammatism; (ii) prominent AOS; and (iii) prominent dysarthria]. None of these data-driven LCDs allowed an accurate prediction of neuropathology. The severity-agrammatism component was an independent predictor of a faster CDR-SB increase in all the participants. Higher dysarthria severity, reduced words per minute and expressive and receptive agrammatism severity at baseline independently predicted accelerated disease progression. Our findings indicate that PPAOS and PAA, rather than exist as completely distinct syndromic entities, constitute a clinical continuum. In our cohort, splitting the nfvPPA spectrum into separate clinical phenotypes did not improve clinical-pathological correlations, stressing the need for new biological markers and consensus regarding updated terminology and clinical classification.
Topics: Humans; Aphasia, Broca; Dysarthria; Apraxias; Language; Speech; Aphasia, Primary Progressive; Primary Progressive Nonfluent Aphasia
PubMed: 37988272
DOI: 10.1093/brain/awad396 -
Journal of Neurology Aug 2023Changes in motor activity are common in individuals with Frontotemporal dementia (FTD). Yet, it remains unclear why some individuals become motorically hyperactive,...
Changes in motor activity are common in individuals with Frontotemporal dementia (FTD). Yet, it remains unclear why some individuals become motorically hyperactive, while others hypoactive even in early stages of the disease. This study aimed to examine the relationship between motor activity level and (1) FTD clinical subtype, and (2) cortical thickness and subcortical volumes. Eighty-two charts were retrospectively reviewed from patients meeting consensus criteria for one of the three main clinical subtypes of FTD: probable bvFTD, semantic variant Primary Progressive Aphasia (PPA), or non-fluent variant PPA. Participants were assigned to one of three groups: (1) hyperactive, (2) hypoactive, or (3) no record of change. Hyperactivity was prevalent among bvFTD (58.5%) and semantic PPA (68.8%) subtypes while hypoactivity was less common in both subtypes (29.3% and 18.8%, respectively). The majority of patients with non-fluent PPA showed no record of change in motor activity (66.7%). The analysis of cortical thickness and subcortical volumes did not identify significant associations with motor activity levels. In conclusion, increased motor activity is highly prevalent among individuals with FTD, especially bvFTD and svPPA subtypes. These findings may inform prognosis and prediction of changes in motor activity, and allow planning for appropriate environmental and behavioural interventions. Future studies with prospective, standardized longitudinal collection of information regarding the type and level of change in motor activity, including wearable measures of actigraphy, may help to further delineate the onset and progression of abnormal motor behaviours and determine neuroanatomic associations in FTD.
Topics: Humans; Frontotemporal Dementia; Retrospective Studies; Motor Activity
PubMed: 37062017
DOI: 10.1007/s00415-023-11713-2 -
Neurobiology of Language (Cambridge,... 2023After a stroke, individuals with aphasia often recover to a certain extent over time. This recovery process may be dependent on the health of surviving brain regions....
After a stroke, individuals with aphasia often recover to a certain extent over time. This recovery process may be dependent on the health of surviving brain regions. Leukoaraiosis (white matter hyperintensities on MRI reflecting cerebral small vessel disease) is one indication of compromised brain health and is associated with cognitive and motor impairment. Previous studies have suggested that leukoaraiosis may be a clinically relevant predictor of aphasia outcomes and recovery, although findings have been inconsistent. We investigated the relationship between leukoaraiosis and aphasia in the first year after stroke. We recruited 267 patients with acute left hemispheric stroke and coincident fluid attenuated inversion recovery MRI. Patients were evaluated for aphasia within 5 days of stroke, and 174 patients presented with aphasia acutely. Of these, 84 patients were evaluated at ∼3 months post-stroke or later to assess longer-term speech and language outcomes. Multivariable regression models were fit to the data to identify any relationships between leukoaraiosis and initial aphasia severity, extent of recovery, or longer-term aphasia severity. We found that leukoaraiosis was present to varying degrees in 90% of patients. However, leukoaraiosis did not predict initial aphasia severity, aphasia recovery, or longer-term aphasia severity. The lack of any relationship between leukoaraiosis severity and aphasia recovery may reflect the anatomical distribution of cerebral small vessel disease, which is largely medial to the white matter pathways that are critical for speech and language function.
PubMed: 37946731
DOI: 10.1162/nol_a_00115 -
Journal of Neurosurgery. Pediatrics Oct 2023Awake craniotomy (AC) is employed to maximize tumor resection while preserving neurological function in eloquent brain tissue. This technique is used frequently in...
OBJECTIVE
Awake craniotomy (AC) is employed to maximize tumor resection while preserving neurological function in eloquent brain tissue. This technique is used frequently in adults but remains poorly established in children. Its use has been limited due to concern for children's neuropsychological differences compared with adults and how these differences may interfere with the safety and feasibility of the procedure. Among studies that have reported pediatric ACs, complication rates and anesthetic management vary. This systematic review was performed to comprehensively analyze outcomes and synthesize anesthetic protocols of pediatric ACs.
METHODS
The authors followed PRISMA guidelines to extract studies that reported AC in children with intracranial pathologies. The Medline/PubMed, Ovid, and Embase databases were searched from database inception to 2021, using the terms ("awake") AND ("Pediatric*" OR "child*") AND (("brain" AND "surgery") OR "craniotomy"). Data extracted included patient age, pathology, and anesthetic protocol. Primary outcomes assessed were premature conversion to general anesthesia, intraoperative seizures, completion of monitoring tasks, and postoperative complications.
RESULTS
Thirty eligible studies published from 1997 to 2020 were included that described a total of 130 children ranging in age from 7 to 17 years who had undergone AC. Of all patients reported, 59% were male and 70% had left-sided lesions. Procedure indications included the following etiologies: tumors (77.6%), epilepsy (20%), and vascular disorders (2.4%). Four (4.1%) of 98 patients required conversion to general anesthesia due to complications or discomfort during AC. In addition, 8 (7.8%) of 103 patients experienced intraoperative seizures. Furthermore, 19 (20.6%) of 92 patients had difficulty completing monitoring tasks. Postoperative complications occurred in 19 (19.4%) of 98 patients and included aphasia (n = 4), hemiparesis (n = 2), sensory deficit (n = 3), motor deficit (n = 4), or others (n = 6). The most commonly reported anesthetic techniques were asleep-awake-asleep protocols using propofol, remifentanil or fentanyl, a local scalp nerve block, and with or without dexmedetomidine.
CONCLUSIONS
The findings of this systematic review suggest the tolerability and safety of ACs in the pediatric population. Although pediatric intracranial pathologies pose etiologies that certainly may benefit from AC, there is a need for surgeons and anesthesiologists to perform individualized risk-benefit analyses due to the risks associated with awake procedures in children. Age-specific, standardized guidelines for preoperative planning, intraoperative mapping, monitoring tasks, and anesthesia protocols will help to continue minimizing complications, while improving tolerability, and streamlining workflow in the treatment of this patient population.
Topics: Adult; Humans; Male; Child; Adolescent; Female; Brain Neoplasms; Wakefulness; Retrospective Studies; Craniotomy; Postoperative Complications; Anesthetics; Seizures
PubMed: 37410631
DOI: 10.3171/2023.4.PEDS22296 -
Neuropsychological Rehabilitation Jun 2024It is unclear whether individuals with agrammatic aphasia have particularly disrupted prosody, or in fact have relatively preserved prosody they can use in a... (Review)
Review
It is unclear whether individuals with agrammatic aphasia have particularly disrupted prosody, or in fact have relatively preserved prosody they can use in a compensatory way. A targeted literature review was undertaken to examine the evidence regarding the capacity of speakers with agrammatic aphasia to produce prosody. The aim was to answer the question, how much prosody can a speaker "do" with limited syntax? The literature was systematically searched for articles examining the production of grammatical prosody in people with agrammatism, and yielded 16 studies that were ultimately included in this review. Participant inclusion criteria, spoken language tasks, and analysis procedures vary widely across studies. The evidence indicates that timing aspects of prosody are disrupted in people with agrammatic aphasia, while the use of pitch and amplitude cues is more likely to be preserved in this population. Some, but not all, of these timing differences may be attributable to motor speech programming deficits (AOS) rather than aphasia, as these conditions frequently co-occur. Many of the included studies do not address AOS and its possible role in any observed effects. Finally, the available evidence indicates that even speakers with severe aphasia show a degree of preserved prosody in functional communication.
PubMed: 38848458
DOI: 10.1080/09602011.2024.2362243 -
Archives of Physical Medicine and... Nov 2023This meta-analysis aimed to examine the overall effectiveness of TMS on post-stroke aphasia using a meta-analysis approach, as well as examine the effect of moderating... (Review)
Review
OBJECTIVE
This meta-analysis aimed to examine the overall effectiveness of TMS on post-stroke aphasia using a meta-analysis approach, as well as examine the effect of moderating variables (eg, study design, TMS protocol) on the effectiveness of TMS.
DATA SOURCES
A keyword search was conducted in 5 databases: ERIC, Google Scholar, PsycINFO, MEDLINE, and ProQuest (01/1985-12/2022). The search algorithm included all possible combinations of relevant keywords. Full-text articles were thoroughly examined using forward/backward search methods.
STUDY SELECTION
Studies were thoroughly screened using the following inclusion criteria: patients were diagnosed with post-stroke aphasia; studies focused on the effect of TMS on post-stroke aphasia; language assessments were conducted at pretest and posttest for TMS treatment and data were reported; studies included both an experimental group (ie, a group with TMS treatment) and a control group (ie, a group without TMS treatment).
DATA EXTRACTION
Information was extracted from each study including authors, publication year, first language of participants, study design, stroke duration, demographics of participants, TMS protocol, stimulation site, targeting, and statistical data of language performance pre- and post-TMS treatment.
DATA SYNTHESIS
A total of 17 studies were included in the final review, involving 682 patients with post-stroke aphasia (348 in the experimental group, 334 in the control group). The results showed that TMS treatment has significant immediate (Hedges' g=0.37) and maintenance (Hedges' g=0.34) effects on post-stroke aphasia. Additionally, the moderating variables showed a moderation effect on the effectiveness of TMS.
CONCLUSION
TMS treatment can significantly improve language ability for post-stroke aphasia. Additionally, this study provides an important reference for selecting the optimal TMS treatment parameters in treating post-stroke aphasia. Specifically, administering 15 sessions of rTMS lasting 10 min over the mirror area within Broca's area may produce the best TMS treatment outcomes.
PubMed: 37984539
DOI: 10.1016/j.apmr.2023.11.006 -
Brain : a Journal of Neurology Jun 2024There is a rich tradition of research on the neuroanatomical correlates of spoken language production in aphasia using constrained tasks (e.g., picture naming), which...
There is a rich tradition of research on the neuroanatomical correlates of spoken language production in aphasia using constrained tasks (e.g., picture naming), which offer controlled insights into the distinct processes that govern speech and language (i.e., lexical-semantic access, morphosyntactic construction, phonological encoding, speech motor programming/execution). Yet these tasks do not necessarily reflect everyday language use. In contrast, naturalistic language production (also referred to as connected speech or discourse) more closely approximates typical processing demands, requiring the dynamic integration of all aspects of speech and language. The brain bases of naturalistic language production remain relatively unknown, however, in part because of the difficulty in deriving features that are salient, quantifiable, and interpretable relative to both speech-language processes and the extant literature. The present cross-sectional observational study seeks to address these challenges by leveraging a validated and comprehensive auditory-perceptual measurement system that yields four explanatory dimensions of performance-Paraphasia (misselection of words and sounds), Logopenia (paucity of words), Agrammatism (grammatical omissions), and Motor speech (impaired speech motor programming/execution). We used this system to characterize naturalistic language production in a large and representative sample of individuals with acute post-stroke aphasia (n = 118). Scores on each of the four dimensions were correlated with lesion metrics, and multivariate associations among the dimensions and brain regions were then explored. Our findings revealed distinct yet overlapping neuroanatomical correlates throughout the left-hemisphere language network. Paraphasia and Logopenia were associated primarily with posterior regions, spanning both dorsal and ventral streams, which are critical for lexical-semantic access and phonological encoding. In contrast, Agrammatism and Motor speech were associated primarily with anterior regions of the dorsal stream that are involved in morphosyntactic construction and speech motor planning/execution respectively. Collectively, we view these results as constituting a brain-behavior model of naturalistic language production in aphasia, aligning with both historical and contemporary accounts of the neurobiology of spoken language production.
PubMed: 38889230
DOI: 10.1093/brain/awae195 -
Brain and Behavior Nov 2023Language deficits are cardinal manifestations of some frontotemporal dementia (FTD) phenotypes and also increasingly recognized in sporadic and familial amyotrophic...
The involvement of language-associated networks, tracts, and cortical regions in frontotemporal dementia and amyotrophic lateral sclerosis: Structural and functional alterations.
BACKGROUND
Language deficits are cardinal manifestations of some frontotemporal dementia (FTD) phenotypes and also increasingly recognized in sporadic and familial amyotrophic lateral sclerosis (ALS). They have considerable social and quality-of-life implications, and adaptive strategies are challenging to implement. While the neuropsychological profiles of ALS-FTD phenotypes are well characterized, the neuronal underpinnings of language deficits are less well studied.
METHODS
A multiparametric, quantitative neuroimaging study was conducted to characterize the involvement of language-associated networks, tracts, and cortical regions with a panel of structural, diffusivity, and functional magnetic resonance imaging (MRI) metrics. Seven study groups were evaluated along the ALS-FTD spectrum: healthy controls (HC), individuals with ALS without cognitive impairment (ALSnci), C9orf72-negative ALS-FTD, C9orf72-positive ALS-FTD, behavioral-variant FTD (bvFTD), nonfluent variant primary progressive aphasia (nfvPPA), and semantic variant PPA (svPPA). The integrity of the Broca's area, Wernicke's area, frontal aslant tract (FAT), arcuate fascicle (AF), inferior occipitofrontal fascicle (IFO), inferior longitudinal fascicle (ILF), superior longitudinal fascicle (SLF), and uncinate fascicle (UF) was quantitatively evaluated. The functional connectivity (FC) between Broca's and Wernicke' areas and FC along the FAT was also specifically assessed.
RESULTS
Patients with nfvPPA and svPPA exhibit distinctive patterns of gray and white matter degeneration in language-associated brain regions. Individuals with bvFTD exhibit Broca's area, right FAT, right IFO, and UF degeneration. The ALSnci group exhibits Broca's area atrophy and decreased FC along the FAT. Both ALS-FTD cohorts, irrespective of C9orf72 status, show bilateral FAT, AF, and IFO pathology. Interestingly, only C9orf72-negative ALS-FTD patients exhibit bilateral uncinate and right ILF involvement, while C9orf72-positive ALS-FTD patients do not.
CONCLUSIONS
Language-associated tracts and networks are not only affected in language-variant FTD phenotypes but also in ALS and bvFTD. Language domains should be routinely assessed in ALS irrespective of the genotype.
Topics: Humans; Frontotemporal Dementia; Amyotrophic Lateral Sclerosis; C9orf72 Protein; Brain; Language
PubMed: 37694825
DOI: 10.1002/brb3.3250