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Cortex; a Journal Devoted To the Study... May 2017Agrammatic aphasia can be observed in neurodegenerative disorders and has been traditionally linked with damage to Broca's area, although there have been disagreements...
Agrammatic aphasia can be observed in neurodegenerative disorders and has been traditionally linked with damage to Broca's area, although there have been disagreements concerning whether damage to Broca's area is necessary or sufficient for the development of agrammatism. We aimed to investigate the neuroanatomical correlates of the emergence of agrammatic aphasia utilizing a unique cohort of patients with primary progressive apraxia of speech (PPAOS) that did not have agrammatism at baseline but developed agrammatic aphasia over time. Twenty PPAOS patients were recruited and underwent detailed speech/language assessments and 3T MRI at two visits, approximately two years apart. None of the patients showed evidence of agrammatism in writing or speech at baseline. Eight patients developed aphasia at follow-up (progressors) and 12 did not (non-progressors). Tensor-based morphometry utilizing symmetric normalization (SyN) was used to assess patterns of grey matter atrophy and voxel-based morphometry was used to assess patterns of grey matter loss at baseline. The progressors were younger at onset and more likely to show distorted sound substitutions or additions compared to non-progressors. Both groups showed change over time in premotor and motor cortices, posterior frontal lobe, basal ganglia, thalamus and midbrain, but the progressors showed greater rates of atrophy in left pars triangularis, thalamus and putamen compared to non-progressors. The progressors also showed greater grey matter loss in pars triangularis and putamen at baseline. This cohort provided a unique opportunity to assess the anatomical changes that accompany the development of agrammatic aphasia. The results suggest that damage to a network of regions including Broca's area, thalamus and basal ganglia are responsible for the development of agrammatic aphasia in PPAOS. Clinical and neuroimaging abnormalities were also present before the onset of agrammatism that could help improve prognosis in these subjects.
Topics: Aphasia; Female; Humans; Magnetic Resonance Imaging; Male; Neurodegenerative Diseases; Neuroimaging; Neuropsychological Tests; Positron-Emission Tomography; Speech
PubMed: 27771043
DOI: 10.1016/j.cortex.2016.09.017 -
Cortex; a Journal Devoted To the Study... Dec 1987Aspects of grammatical morphology in Broca's and Wernicke's aphasia were elicited under controlled conditions in three language groups: English, Italian and German.... (Comparative Study)
Comparative Study Review
Aspects of grammatical morphology in Broca's and Wernicke's aphasia were elicited under controlled conditions in three language groups: English, Italian and German. Results suggest that the agrammatism/paragrammatism distinction does not work well for richly-inflected languages. Language-specific ratios of closed class morphology were preserved even among non-fluent patients, with significantly more morphology produced by German and Italian patients. German and Italian patients were also much more likely to furnish the article before nouns--despite or perhaps because of the fact that articles are more complex and informative in those languages. Although patients assigned the correct article most of the time, there were a significant number of article errors (i.e. paragrammatic substitution). Error analyses showed that substitutions are not random, reflecting difficulty in access rather than loss. Substitutions were more common in German, where the complex case and gender markings on the article increase the probability of error. Within each language, error patterns were quite similar for Broca's and Wernicke's aphasics. However, at a detailed level patient group differences in error production were detected. German Broca's aphasics tend to avoid difficult case forms by substituting a simpler, less-marked morphosyntactic frame. Wernicke's aphasics try instead to produce the more marked, oblique constructions, resulting in a less conservative error pattern.
Topics: Animals; Aphasia; Aphasia, Broca; Aphasia, Wernicke; Language; Language Tests
PubMed: 3327655
DOI: 10.1016/s0010-9452(87)80049-7 -
Annals of Rehabilitation Medicine Dec 2011Crossed aphasia refers to language disturbance due to right-hemisphere lesions in right-handed individuals, while magnetic apraxia is described as 'forced grasping and...
Crossed aphasia refers to language disturbance due to right-hemisphere lesions in right-handed individuals, while magnetic apraxia is described as 'forced grasping and groping' caused by lesions in the contralateral frontal lobe. This is a case report of a 70-year-old right handed woman who suffered from crossed transcortical motor aphasia and left hand magnetic apraxia due to right anterior cerebral artery infarction. The definite mechanism of this disorder is not yet understood, but neurophysiological observations suggest that affected supplementary motor areas may be responsible for this phenomenon.
PubMed: 22506227
DOI: 10.5535/arm.2011.35.6.949 -
Brain and Language Feb 2014The left insula or Broca's area have been proposed as the neuroanatomical correlate for apraxia of speech (AOS) based on studies of patients with both AOS and aphasia...
The left insula or Broca's area have been proposed as the neuroanatomical correlate for apraxia of speech (AOS) based on studies of patients with both AOS and aphasia due to stroke. Studies of neurodegenerative AOS suggest the premotor area and the supplementary motor areas as the anatomical correlates. The study objective was to determine the common infarction area in patients with pure AOS due to stroke. Patients with AOS and no or equivocal aphasia due to ischemic stroke were identified through a pre-existing database. Seven subjects were identified. Five had pure AOS, and two had equivocal aphasia. MRI lesion analysis revealed maximal overlap spanning the left premotor and motor cortices. While both neurodegenerative AOS and stroke induced pure AOS involve the premotor cortex, further studies are needed to establish whether stroke-induced AOS and neurodegenerative AOS share a common anatomic substrate.
Topics: Aged; Aphasia; Apraxias; Female; Frontal Lobe; Humans; Language; Magnetic Resonance Imaging; Male; Middle Aged; Motor Cortex; Prefrontal Cortex; Speech; Stroke
PubMed: 24556336
DOI: 10.1016/j.bandl.2014.01.004 -
Annals of Physical and Rehabilitation... May 2022The Mini Mental State Examination and Montreal Cognitive Assessment are commonly used as short screening batteries for assessing cognitive impairment after stroke....
BACKGROUND
The Mini Mental State Examination and Montreal Cognitive Assessment are commonly used as short screening batteries for assessing cognitive impairment after stroke. However, aphasia or hemispatial neglect may interfere with the results. For this reason, we developed the Cognitive Assessment scale for Stroke Patients (CASP), which takes these conditions into consideration and previously demonstrated its superiority over these scales in terms of feasibility.
OBJECTIVES
Our goal was to verify the psychometric properties of the (original) French version of the CASP.
METHODS
We included 201 patients with a recent first hemispheric stroke and 50 controls. Stroke patients were examined 4 times (visit 1 [V1] to visit 4 [V4]) in the subacute post-stroke phase. The structural validity of the CASP was studied by principal factorial analysis, convergent validity by comparison with several variables including a comprehensive neuropsychological assessment, divergent validity by comparison with the total score between stroke patients and controls, and sub-scores between right and left stroke. Internal consistency, reproducibility and sensitivity to change were assessed. We propose the Minimal Clinically Important Difference (MCID) value and a pathological threshold as well as a threshold to predict cognitive change between V1 and V4.
RESULTS
Of the 201 participants included (63% male; mean [SD] age 63 [13] years), CASP data were available for 199/150/133/93 at V1/V2/V3/V4, respectively. CASP has a one-dimensional structure. The hypotheses of convergent/divergent validities were confirmed. Internal consistency was good and reliability excellent. Responsiveness was small to moderate, but the MCID could still be estimated. We discuss the choice of a pathological threshold and a predictive threshold of V1 over V4.
CONCLUSIONS
CASP has good psychometric properties for screening cognitive impairment in the subacute post-stroke phase, which is consistent with its Italian and Korean versions. It can be used for patients with severe motor aphasia or left hemispatial neglect but not in case of severe oral comprehension or visual impairment.
Topics: Aphasia; Cognition; Female; Humans; Male; Middle Aged; Neuropsychological Tests; Perceptual Disorders; Psychometrics; Reproducibility of Results; Stroke
PubMed: 34687958
DOI: 10.1016/j.rehab.2021.101594 -
Neurobiology of Aging Dec 2022Primary progressive apraxia of speech (PPAOS) is a neurodegenerative motor speech disorder affecting the ability to produce speech. If agrammatic aphasia is present, it...
Primary progressive apraxia of speech (PPAOS) is a neurodegenerative motor speech disorder affecting the ability to produce speech. If agrammatic aphasia is present, it can be referred to as the non-fluent/agrammatic variant of primary progressive aphasia (nfvPPA). We investigated whether resting-state functional MRI (rs-fMRI) connectivity from disease "epicenters" correlated with longitudinal gray matter atrophy and hypometabolism in nfvPPA and PPAOS. Eighteen nfvPPA and 23 PPAOS patients underwent clinical assessment, structural MRI, rs-fMRI, and [F] fluorodeoxyglucose (FDG)-PET at baseline and ∼2 years follow-up. Rates of neurodegeneration in nfvPPA and PPAOS correlated with functional connectivity to the premotor, motor, and frontal cortex. Connectivity to the caudate and thalamus was more strongly associated with rates of hypometabolism than atrophy. Connectivity to the left Broca's area was more strongly associated with rates of atrophy and hypometabolism in nfvPPA. Finally, functional connectivity to a network of regions, and not to a single epicenter, correlated with rates of neurodegeneration in PPAOS and nfvPPA, suggesting similar biological mechanisms driving disease progression, with regional differences related to language.
Topics: Humans; Speech; Motor Cortex; Fluorodeoxyglucose F18; Apraxias; Brain; Magnetic Resonance Imaging; Primary Progressive Nonfluent Aphasia; Atrophy; Aphasia, Primary Progressive
PubMed: 36166918
DOI: 10.1016/j.neurobiolaging.2022.08.013 -
Brain : a Journal of Neurology Dec 2019Non-fluent speech is one of the most common impairments in post-stroke aphasia. The rehabilitation of non-fluent speech in aphasia is particularly challenging as...
Non-fluent speech is one of the most common impairments in post-stroke aphasia. The rehabilitation of non-fluent speech in aphasia is particularly challenging as patients are rarely able to produce and practice fluent speech production. Speech entrainment is a behavioural technique that enables patients with non-fluent aphasia to speak fluently. However, its mechanisms are not well understood and the level of improved fluency with speech entrainment varies among individuals with non-fluent aphasia. In this study, we evaluated the behavioural and neuroanatomical factors associated with better speech fluency with the aid of speech entrainment during the training phase of speech entrainment. We used a lesion-symptom mapping approach to define the relationship between chronic stroke location on MRI and the number of different words per second produced during speech entrainment versus picture description spontaneous speech. The behavioural variable of interest was the speech entrainment/picture description ratio, which, if ≥1, indicated an increase in speech output during speech entrainment compared to picture description. We used machine learning (shallow neural network) to assess the statistical significance and out-of-sample predictive accuracy of the neuroanatomical model, and its regional contributors. We observed that better assisted speech (higher speech entrainment/picture description ratio) was achieved by individuals who had preservation of the posterior middle temporal gyrus, inferior fronto-occipital fasciculus and uncinate fasciculus, while exhibiting lesions in areas typically associated with non-fluent aphasia, such as the superior longitudinal fasciculus, precentral, inferior frontal, supramarginal and insular cortices. Our findings suggest that individuals with dorsal stream damage but preservation of ventral stream structures are more likely to achieve more fluent speech with the aid of speech entrainment compared to spontaneous speech. This observation provides insight into the mechanisms of non-fluent speech in aphasia and has potential implications for future research using speech entrainment for rehabilitation of non-fluent aphasia.
Topics: Aged; Aphasia, Broca; Brain; Brain Mapping; Female; Humans; Language; Magnetic Resonance Imaging; Male; Middle Aged; Speech; Stroke
PubMed: 31580418
DOI: 10.1093/brain/awz309 -
Revista de NeurologiaSemantic dementia is a progressive, relatively selective disorder affecting the semantic system with involvement of the verbal and non-verbal functions. The clinical... (Review)
Review
INTRODUCTION
Semantic dementia is a progressive, relatively selective disorder affecting the semantic system with involvement of the verbal and non-verbal functions. The clinical picture is well characterised despite the confusion that may be generated by the different ways of classifying it. AIM. To determine the clinical, neurolinguistic, imaging and pathological features of this progressive language disorder.
DEVELOPMENT
Evaluation of language reveals above all the existence of semantic paraphasias, disorders affecting the comprehension of isolated words and surface dyslexia. Flow of speech, complex syntactic comprehension and grammar are preserved. Both episodic and autobiographic memory are close to normality. Both the clinical signs and symptoms and imaging studies agree on the fact that the most heavily affected area is the anteroinferomedial region of the temporal lobe on a bilateral scale but with predominance of the left-hand side. Pathologically, in most cases positive intraneuronal ubiquitin inclusions are observed like those described in motor neuron diseases.
CONCLUSIONS
Semantic dementia constitutes a diagnosis challenge, mainly from the neuropsychological point of view. Further advances towards reaching a diagnosis would allow us to determine which area is mainly affected and, in the future, to find an effective treatment for this progressive, degenerative disorder.
Topics: Aged; Aphasia, Broca; Brain Mapping; Dementia; Disease Progression; Female; Frontal Lobe; Humans; Magnetic Resonance Imaging; Male; Mental Disorders; Middle Aged; Semantics; Temporal Lobe; Tomography, Emission-Computed, Single-Photon; Verbal Behavior
PubMed: 17133330
DOI: No ID Found -
Behavioural Neurology 2015In a majority of languages, the time of an event is expressed by marking tense on the verb. There is substantial evidence that the production of verb tense in sentences... (Meta-Analysis)
Meta-Analysis Review
In a majority of languages, the time of an event is expressed by marking tense on the verb. There is substantial evidence that the production of verb tense in sentences is more severely impaired than other functional categories in persons with agrammatic aphasia. The underlying source of this verb tense impairment is less clear, particularly in terms of the relative contribution of conceptual-semantic and processing demands. This study aimed to provide a more precise characterization of verb tense impairment by examining if there is dissociation within tenses (due to conceptual-semantic differences) and an effect of experimental task (mediated by processing limitations). Two sources of data were used: a meta-analysis of published research (which yielded 143 datasets) and new data from 16 persons with agrammatic aphasia. Tensed verbs were significantly more impaired than neutral (nonfinite) verbs, but there were no consistent differences between past, present, and future tenses. Overall, tense accuracy was mediated by task, such that picture description task was the most challenging, relative to sentence completion, sentence production priming, and grammaticality judgment. An interaction between task and tense revealed a past tense disadvantage for a sentence production priming task. These findings indicate that verb tense impairment is exacerbated by processing demands of the elicitation task and the conceptual-semantic differences between tenses are too subtle to show differential performance in agrammatism.
Topics: Aphasia, Broca; Humans; Language; Speech
PubMed: 26457004
DOI: 10.1155/2015/983870 -
Neurology Nov 2017To determine whether baseline clinical and MRI features predict rate of clinical decline in patients with progressive apraxia of speech (AOS).
OBJECTIVE
To determine whether baseline clinical and MRI features predict rate of clinical decline in patients with progressive apraxia of speech (AOS).
METHODS
Thirty-four patients with progressive AOS, with AOS either in isolation or in the presence of agrammatic aphasia, were followed up longitudinally for up to 4 visits, with clinical testing and MRI at each visit. Linear mixed-effects regression models including all visits (n = 94) were used to assess baseline clinical and MRI variables that predict rate of worsening of aphasia, motor speech, parkinsonism, and behavior. Clinical predictors included baseline severity and AOS type. MRI predictors included baseline frontal, premotor, motor, and striatal gray matter volumes.
RESULTS
More severe parkinsonism at baseline was associated with faster rate of decline in parkinsonism. Patients with predominant sound distortions (AOS type 1) showed faster rates of decline in aphasia and motor speech, while patients with segmented speech (AOS type 2) showed faster rates of decline in parkinsonism. On MRI, we observed trends for fastest rates of decline in aphasia in patients with relatively small left, but preserved right, Broca area and precentral cortex. Bilateral reductions in lateral premotor cortex were associated with faster rates of decline of behavior. No associations were observed between volumes and decline in motor speech or parkinsonism.
CONCLUSIONS
Rate of decline of each of the 4 clinical features assessed was associated with different baseline clinical and regional MRI predictors. Our findings could help improve prognostic estimates for these patients.
Topics: Aged; Aphasia; Apraxias; Female; Humans; Longitudinal Studies; Magnetic Resonance Imaging; Male; Middle Aged; Neuropsychological Tests; Outcome Assessment, Health Care; Parkinson Disease; Predictive Value of Tests; Problem Behavior; Severity of Illness Index
PubMed: 29093069
DOI: 10.1212/WNL.0000000000004685