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OBJECTIVE: To determine whether MRI-based cerebral small vessel disease (cSVD) burden predicts treatment-induced aphasia recovery in chronic stroke patients above and beyond initial aphasia severity and stroke-lesion volume. DESIGN: Retrospective. Four cSVD neuroimaging markers were rated using validated visual scales: white matter hyperintensities, enlarged perivascular spaces, lacunes, and global cortical atrophy. We also calculated a cSVD total score. We employed linear regression models to model treatment response as a function of cSVD burden. We also ran correlation analyses to determine the association among cSVD burden and pre-treatment linguistic and non-linguistic cognition. SETTING: Research clinic. PARTICIPANTS: The study includes data from 30 chronic stroke patients with aphasia who received treatment for word finding difficulties and completed additional pre-treatment neuroimaging and behavioral assessments (N=30). INTERVENTIONS: 120-minute sessions of anomia treatment 2 times per week for up to 12 weeks. MAIN OUTCOME MEASURES: Change in accuracy on the treatment probes measured as a percentage (ie, change in accuracy percentage score=post-treatment accuracy percentage minus pre-treatment accuracy percentage). RESULTS: Baseline cSVD burden predicted response to anomia treatment independently from demographic and stroke-related factors. Patients with lower cSVD burden exhibited enhanced rehabilitation response compared with those with higher cSVD burden (ß=-6.816e-02, P=.019). cSVD burden was highly associated with nonverbal executive function at baseline (r=-0.49, P=.005): patients with lower cSVD burden exhibited higher performance on nonverbal executive function tasks compared with participants with higher cSVD burden. No association was observed among cSVD burden and performance on language tasks at the baseline. CONCLUSIONS: cSVD, a marker of brain reserve and a robust risk factor for post-stroke dementia, may be used as a biomarker for distinguishing patients who are more likely to respond to anomia therapy from those who are less likely to do so and for individualizing treatment parameters (eg, targeting both linguistic and nonlinguistic cognition in severe cSVD).
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Afasia , Enfermedades de los Pequeños Vasos Cerebrales , Accidente Cerebrovascular , Humanos , Anomia/complicaciones , Estudios Retrospectivos , Accidente Cerebrovascular/complicaciones , Enfermedades de los Pequeños Vasos Cerebrales/complicaciones , Afasia/etiología , Imagen por Resonancia Magnética/métodos , BiomarcadoresRESUMEN
OBJECTIVE: Anomia is usually assessed using picture-naming tests. While many tests evaluate anomia for nouns, very few tests have been specifically designed for verb anomia. This article presents the DVAQ-30, a new naming test for detecting verb anomia in adults and elderly people. METHOD: The article describes three studies. Study 1 focused on the DVAQ-30 development phase. In Study 2, healthy participants and individuals with post-stroke aphasia, mild cognitive impairment, Alzheimer's disease, or primary progressive aphasia were assessed using the DVAQ-30 to establish its convergent and discriminant validity, test-retest reliability, and internal consistency. In Study 3, a group of adults and elderly Quebec French-speaking adults were assessed to obtain normative data. RESULTS: The DVAQ-30 had good convergent validity and distinguished the performance of healthy participants from that of participants with pathological conditions. The test also had good internal consistency, and the test-retest analysis showed that the scores had good temporal stability. Furthermore, normative data were collected on the performance of 244 participants aged 50 years old and over. CONCLUSIONS: The DVAQ-30 fills an important gap and has the potential to help clinicians and researchers better detect verb anomia associated with pathological aging and post-stroke aphasia.
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Anomia , Afasia , Adulto , Anciano , Humanos , Persona de Mediana Edad , Anomia/etiología , Anomia/complicaciones , Reproducibilidad de los Resultados , Pruebas Neuropsicológicas , Afasia/complicaciones , Afasia/diagnóstico , Lenguaje , SemánticaRESUMEN
Preoperative language deficits are associated with alterations in the language networks of patients with gliomas. This study investigated how gliomas affect language performance by altering the language network. Ninety patients with lower-grade gliomas were included, and their preoperative language performance was evaluated using the Western Aphasia Battery. We also calculated the topological properties based on resting state functional magnetic resonance imaging. All patients were classified according to aphasia quotient (AQ) into the aphasia (AQ < 93.8), mild anomia (AQ > 93.8 and naming section <9.8), and normal groups (AQ > 93.8). The shortest distance from the tumor to the language network (SDTN) was evaluated to identify the effect on language performance induced by the tumor. One-way analysis of variance and post hoc analysis with Sidak correction were used to analyze the differences in topological properties among the three groups. Causal mediation analysis was used to identify indirectly affected mediators. Compared with the mild anomia group, longer shortest path length (p = .0016), lower vulnerability (p = .0331), and weaker nodal efficiencies of three nodes (right caudal Brodmann area [BA] 45, right caudal BA 22, and left BA 41/42, all p < .05) were observed in the aphasia group. The SDTN mediated nodal degree centrality and nodal vulnerability (left rostroventral BA 39), which negatively affected the AQs. Conventional language eloquent and mirrored areas participated in the language network alterations induced by gliomas. The SDTN was a mediator that affected the preoperative language status in patients with gliomas.
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Afasia , Glioma , Humanos , Anomia/complicaciones , Imagen por Resonancia Magnética , Afasia/diagnóstico por imagen , Afasia/etiología , Afasia/patología , Lenguaje , Glioma/complicaciones , Glioma/diagnóstico por imagen , Glioma/patología , Mapeo EncefálicoRESUMEN
INTRODUCTION: A third of frontotemporal dementia (FTD) is caused by an autosomal-dominant genetic mutation in one of three genes: microtubule-associated protein tau (MAPT), chromosome 9 open reading frame 72 (C9orf72) and progranulin (GRN). Prior studies of prodromal FTD have identified impaired executive function and social cognition early in the disease but few have studied naming in detail. METHODS: We investigated performance on the Boston Naming Test (BNT) in the GENetic Frontotemporal dementia Initiative cohort of 499 mutation carriers and 248 mutation-negative controls divided across three genetic groups: C9orf72, MAPT and GRN. Mutation carriers were further divided into 3 groups according to their global CDR plus NACC FTLD score: 0 (asymptomatic), 0.5 (prodromal) and 1 + (fully symptomatic). Groups were compared using a bootstrapped linear regression model, adjusting for age, sex, language and education. Finally, we identified neural correlates of anomia within carriers of each genetic group using a voxel-based morphometry analysis. RESULTS: All symptomatic groups performed worse on the BNT than controls with the MAPT symptomatic group scoring the worst. Furthermore, MAPT asymptomatic and prodromal groups performed significantly worse than controls. Correlates of anomia in MAPT mutation carriers included bilateral anterior temporal lobe regions and the anterior insula. Similar bilateral anterior temporal lobe involvement was seen in C9orf72 mutation carriers as well as more widespread left frontal atrophy. In GRN mutation carriers, neural correlates were limited to the left hemisphere, and involved frontal, temporal, insula and striatal regions. CONCLUSION: This study suggests the development of early anomia in MAPT mutation carriers, likely to be associated with impaired semantic knowledge. Clinical trials focused on the prodromal period within individuals with MAPT mutations should use language tasks, such as the BNT for patient stratification and as outcome measures.
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Anomia , Demencia Frontotemporal , Proteínas tau , Anomia/complicaciones , Proteína C9orf72/genética , Demencia Frontotemporal/complicaciones , Demencia Frontotemporal/diagnóstico por imagen , Demencia Frontotemporal/genética , Humanos , Mutación , Progranulinas/genética , Proteínas tau/genéticaRESUMEN
BACKGROUND: Auditory naming tests are superior to visual confrontation naming tests in revealing word-finding difficulties in many neuropathological conditions. OBJECTIVE: To delineate characteristics of auditory naming most likely to reveal anomia in patients with dementia, and possibly improve diagnostic utility, we evaluated a large sample of patients referred with memory impairment complaints. METHODS: Patients with dementia (Nâ=â733) or other cognitive impairments and normal individuals (Nâ=â69) were evaluated for frequency of impairment on variables of the Auditory Naming Test (ANT) of Hamberger & Seidel versus the Boston Naming Test (BNT). RESULTS: Naming impairment occurred more frequently using the ANT total score (φ=â0.41) or ANT tip-of-the tongue score (TOT; φ=â0.19) but not ANT mean response time compared to the BNT in patients with dementia (pâ<â0.001). Significantly more patients were impaired on ANT variables than on the BNT in Alzheimer's disease (AD), vascular dementia (VaD), mixed AD/VaD, and multiple domain mild cognitive impairment (mMCI) but not in other dementias or amnestic MCI (aMCI). This differential performance of patients on auditory versus visual naming tasks was most pronounced in older, well-educated, male patients with the least cognitive impairment. Impaired verbal comprehension was not contributory. Inclusion of an ANT index score increased sensitivity in the dementia sample (92%). Poor specificity (41%) may be secondary to the inherent limitation of using the BNT as a control variable. CONCLUSION: The ANT index score adds diagnostic utility to the assessment of naming difficulties in patients with suspected dementia.
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Anomia/diagnóstico , Disfunción Cognitiva/complicaciones , Demencia/complicaciones , Anciano , Anciano de 80 o más Años , Anomia/complicaciones , Anomia/psicología , Disfunción Cognitiva/psicología , Demencia/psicología , Femenino , Humanos , Pruebas del Lenguaje , Masculino , Persona de Mediana Edad , Pruebas NeuropsicológicasRESUMEN
Four right-handed patients who presented with an isolated impairment of speech or language had transactive response DNA-binding protein of 43 kDa (TDP-43) type B pathology. Comportment and pyramidal motor function were preserved at presentation. Three of the cases developed axial rigidity and oculomotor findings late in their course with no additional pyramidal or lower motor neuron impairments. However, in all 4 cases, postmortem examination disclosed some degree of upper and lower motor neuron disease (MND) pathology in motor cortex, brainstem, and spinal cord. Although TDP-43 type B pathology is commonly associated with MND and behavioral variant frontotemporal dementia, it is less recognized as a pathologic correlate of primary progressive aphasia and/or apraxia of speech as the presenting syndrome. These cases, taken together, contribute to the growing heterogeneity in clinical presentations associated with TDP pathology. Additionally, 2 cases demonstrated left anterior temporal lobe atrophy but without word comprehension impairments, shedding light on the relevance of the left temporal tip for single-word comprehension.
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Anomia/patología , Afasia de Broca/patología , Apraxias/patología , Encéfalo/patología , Degeneración Lobar Frontotemporal/complicaciones , Degeneración Lobar Frontotemporal/patología , Anomia/complicaciones , Afasia de Broca/complicaciones , Apraxias/complicaciones , Proteínas de Unión al ADN/metabolismo , Degeneración Lobar Frontotemporal/psicología , Humanos , Cuerpos de Inclusión/metabolismo , Cuerpos de Inclusión/patología , Masculino , Persona de Mediana Edad , Proteinopatías TDP-43/complicaciones , Proteinopatías TDP-43/patología , Proteinopatías TDP-43/psicologíaRESUMEN
The same language symptom might arise at different functional loci in people with aphasia. Therefore, it is plausible that different therapeutic interventions should be adopted to approach the same difficulties in different patients. Although this point of view is still widely accepted, recently the focus has shifted from the functional locus of a rehabilitative intervention to the mechanisms of action underlying the relearning process. We maintain that both aspects should be taken into account when programming a rehabilitative intervention; furthermore, investigating relearning mechanisms might shed new light on the functional architecture of the disrupted processes. Here, we investigated, in a single case study, whether classical conditioning was a suitable relearning paradigm for targeting word-finding difficulties in pure anomia, that is in a patient with an impairment in accessing intact output lexical representations from a spared semantic system. Using a word-repetition task on picture presentation, we contrasted a condition in which the stimulus onset asynchrony between word and picture stimuli was well suited to produce classical conditioning with a condition in which repetition training could not benefit from this learning mechanism. Only classical conditioning training exerted a significant, long-lasting effect on our patient's naming skill. Tentative implications of our results for the functional architecture of single-word processing are discussed.
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Anomia/complicaciones , Condicionamiento Clásico/fisiología , Discapacidades para el Aprendizaje/etiología , Semántica , Atención/fisiología , Femenino , Humanos , Pruebas del Lenguaje , Discapacidades para el Aprendizaje/diagnóstico , Masculino , Memoria/fisiología , Pruebas Neuropsicológicas , VocabularioRESUMEN
Many individuals with aphasia describe anomia with comments like "I know it but I can't say it." The exact meaning of such phrases is unclear. We hypothesize that at least two discrete experiences exist: the sense of (1) knowing a concept, but failing to find the right word, and (2) saying the correct word internally but not aloud (successful inner speech, sIS). We propose that sIS reflects successful lexical access; subsequent overt anomia indicates post-lexical output deficits. In this pilot study, we probed the subjective experience of anomia in 37 persons with aphasia. Self-reported sIS related to aphasia severity and phonological output deficits. In multivariate lesion-symptom mapping, sIS was associated with dorsal stream lesions, particularly in ventral sensorimotor cortex. These preliminary results suggest that people with aphasia can often provide meaningful insights about their experience of anomia and that reports of sIS relate to specific lesion locations and language deficits.
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Anomia/fisiopatología , Anomia/psicología , Afasia/fisiopatología , Afasia/psicología , Adulto , Anciano , Anciano de 80 o más Años , Anomia/complicaciones , Anomia/patología , Afasia/complicaciones , Afasia/patología , Femenino , Humanos , Pruebas del Lenguaje , Masculino , Persona de Mediana Edad , Proyectos Piloto , Autoinforme , Corteza Sensoriomotora/patología , Corteza Sensoriomotora/fisiopatología , HablaRESUMEN
Aphasia is a chronic condition that usually requires long-term rehabilitation. However, even if many effective treatments can be offered to patients and families, speech therapy services for individuals with aphasia often remain limited because of logistical and financial considerations, especially more than 6 months after stroke. Therefore, the need to develop tools to maximize rehabilitation potential is unquestionable. The aim of this study was to test the efficacy of a self-administered treatment delivered with a smart tablet to improve written verb naming skills in CP, a 63-year-old woman with chronic aphasia. An ABA multiple baseline design was used to compare CP's performance in verb naming on three equivalent lists of stimuli trained with a hierarchy of cues, trained with no cues, and not trained. Results suggest that graphemic cueing therapy, done four times a week for 3 weeks, led to better written verb naming compared to baseline and to the untrained list. Moreover, generalization of the effects of treatment was observed in verb production, assessed with a noun-to-verb production task. Results of this study suggest that self-administered training with a smart tablet is effective in improving naming skills in chronic aphasia. Future studies are needed to confirm the effectiveness of new technologies in self-administered treatment of acquired language deficits.
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Anomia/terapia , Afasia/terapia , Terapia del Lenguaje/métodos , Terapia Asistida por Computador , Anomia/complicaciones , Afasia/complicaciones , Computadoras de Mano , Femenino , Humanos , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
INTRODUCTION: Language impairment is frequently observed in patients with Alzheimer's disease (AD): in this study, we investigated the extent and distribution of brain atrophy in subjects with conversion from mild cognitive impairment (MCI) to AD with and without naming difficulties. METHODS: This study was approved by the institutional review board and was HIPAA compliant. All subjects or their legal representatives gave informed consent for participation. Ninety-one subjects from the Alzheimer's Disease Neuroimaging Initiative (ADNI) with (N = 51) and without (N = 40) naming impairment as per the Boston Naming Test (BNT), underwent brain magnetic resonance (MR) imaging 12 months before, at AD diagnosis, and 12 months after. Structural MR images were processed using voxel-based morphometry. Cross-sectional comparisons and mixed ANOVA models for assessing regional gray matter (GM) volume differences were performed. RESULTS: As from 12 months prior to AD diagnosis, patients with naming difficulties showed distinct areas of greater GM loss in the left fusiform gyrus (Brodmann area 20) than patients without naming difficulties. Differences in the GM atrophy extended to the left hemisphere in the subsequent 12 months. CONCLUSION: This study provided evidence of distinct patterns and dynamics of brain atrophy in AD patients with naming difficulties when compared to those with intact language, as early as 12 months prior to AD diagnosis and in the subsequent 12 months.
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Enfermedad de Alzheimer/etiología , Anomia/complicaciones , Disfunción Cognitiva/complicaciones , Anciano , Atrofia , Encéfalo/patología , Estudios Transversales , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Estudios Retrospectivos , Factores de TiempoRESUMEN
We present two patients in whom the combination of lesion site and cognitive performance was uniquely informative about the organisation and functional anatomy of semantic memory. One had had a single lobar stroke with an unusual distribution, largely destroying the whole of the left temporal lobe ventral to the superior temporal sulcus. The other patient had had herpes simplex encephalitis with destruction that was confined to the left cerebral hemisphere. The lesion again mainly encompassed the left temporal lobe, but also extended to the left inferior frontal gyrus. Cognitive outcomes in the two patients were compared with each other and with published results from patients with semantic dementia. This is because, whereas the majority of semantic dementia patients present with more prominent atrophy of the left rostroventral temporal lobe, they invariably have a degree of atrophy in the mirror region on the right that progresses. Semantic dementia therefore provides no clear evidence about the specific role of the left rostroventral temporal lobe. The two patients showed a highly consistent cognitive profile. Their deficits were also similar in many respects to that observed in patients with mild-moderate semantic dementia, including severe anomia that was not resolved by phonological cues and impairment on non-verbal as well as verbal semantic tasks. Certain key features of the semantic dementia profile, however-including sensitivity to the familiarity and typicality of the stimulus materials-appeared only in tasks requiring verbal output in these two patients with unilateral left temporal lesions. Results in these cases provide some of the first definitive evidence regarding the specific functions of the left anterior temporal lobe.
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Demencia Frontotemporal/diagnóstico , Lóbulo Temporal/patología , Adulto , Anciano , Anomia/complicaciones , Hemorragia Cerebral/complicaciones , Demencia Frontotemporal/complicaciones , Demencia Frontotemporal/etiología , Demencia Frontotemporal/patología , Lateralidad Funcional , Humanos , Masculino , Pruebas Neuropsicológicas , Reconocimiento en Psicología/fisiología , Accidente Cerebrovascular/complicacionesRESUMEN
The semantic variant of primary progressive aphasia (svPPA) is known to affect the comprehension and production of all content words, including verbs. However, studies of the treatment of anomia in this disorder focused on relearning object names only. This study reports treatment of verb anomia in an individual with svPPA. The semantic-phonological cueing therapy resulted in significant improvement in naming abilities, for treated verbs only. This case study demonstrates that improvement in verb-naming abilities may be possible in svPPA. The almost complete maintenance of the treatment's effects in the patient 4 weeks after the end of the therapy also suggests improvements may be durable, at least in the short term, for some individuals with svPPA.
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Anomia/rehabilitación , Afasia Progresiva Primaria/complicaciones , Señales (Psicología) , Semántica , Anciano , Anomia/complicaciones , Femenino , Humanos , Pruebas Neuropsicológicas , Fonética , Resultado del TratamientoRESUMEN
We aimed to characterize difficulties in famous face naming in three poststroke aphasic patients with a lesion limited to the left mid-posterior temporal language regions, sparing the anterior temporal lobe. The patients did not present semantic deficits specific to known people. Nonetheless, they showed difficulties naming famous buildings in addition to famous faces, but they were comparable to healthy controls in generating proper names. Our results support the critical role of the mid-posterior temporal language regions in the lexical retrieval of proper names, namely from pictorial stimuli, in absence of semantic impairments.
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Anomia/patología , Afasia/patología , Recuerdo Mental/fisiología , Accidente Cerebrovascular/complicaciones , Lóbulo Temporal/patología , Anciano , Anomia/complicaciones , Afasia/complicaciones , Personajes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nombres , SemánticaRESUMEN
We report a case of frontotemporal dementia caused by a novel MAPT mutation (Q351R) with a remarkably long amnestic presentation mimicking familial Alzheimer's disease. Longitudinal clinical, neuropsychological and imaging data provide convergent evidence for predominantly bilateral anterior medial temporal lobe involvement consistent with previously established neuroanatomical signatures of MAPT mutations. This case supports the notion that the neural network affected in MAPT mutations is determined to a large extent by the underlying molecular pathology. We discuss the diagnostic significance of anomia in the context of atypical amnesia and the impact of impaired episodic and semantic memory systems on autobiographical memory.
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Amnesia/complicaciones , Demencia Frontotemporal/diagnóstico , Demencia Frontotemporal/genética , Mutación , Proteínas tau/genética , Enfermedad de Alzheimer/diagnóstico , Anomia/complicaciones , Encéfalo/patología , Progresión de la Enfermedad , Femenino , Demencia Frontotemporal/complicaciones , Hipocampo/patología , Humanos , Persona de Mediana EdadRESUMEN
The paper reports findings derived from three experiments examining syntactic and morphosyntactic processing in individuals with agrammatic and logopenic variants of primary progressive aphasia (PPA-G and PPA-L, respectively) and stroke-induced agrammatic and anomic aphasia (StrAg and StrAn, respectively). We examined comprehension and production of canonical and noncanonical sentence structures and production of tensed and nontensed verb forms using constrained tasks in experiments 1 and 2, using the Northwestern Assessment of Verbs and Sentences (NAVS [57]) and the Northwestern Assessment of Verb Inflection (NAVI, Thompson and Lee, experimental version) test batteries, respectively. Experiment 3 examined free narrative samples, focusing on syntactic and morphosyntactic measures, i.e. production of grammatical sentences, noun to verb ratio, open-class to closed-class word production ratio, and the production of correctly inflected verbs. Results indicate that the two agrammatic groups (i.e., PPA-G and StrAg) pattern alike on syntactic and morphosyntactic measures, showing more impaired noncanonical compared to canonical sentence comprehension and production and greater difficulties producing tensed compared to nontensed verb forms. Their spontaneous speech also contained significantly fewer grammatical sentences and correctly inflected verbs, and they produced a greater proportion of nouns compared to verbs, than healthy speakers. In contrast, PPA-L and StrAn individuals did not display these deficits, and performed significantly better than the agrammatic groups on these measures. The findings suggest that agrammatism, whether induced by degenerative disease or stroke, is associated with characteristic deficits in syntactic and morphosyntactic processing. We therefore recommend that linguistically sophisticated tests and narrative analysis procedures be used to systematically evaluate the linguistic ability of individuals with PPA, contributing to our understanding of the language impairments of different PPA variants.
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Anomia/psicología , Afasia de Broca/psicología , Afasia Progresiva Primaria/psicología , Comprensión , Semántica , Accidente Cerebrovascular/psicología , Anciano , Anomia/complicaciones , Afasia de Broca/complicaciones , Afasia Progresiva Primaria/diagnóstico , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas/estadística & datos numéricos , Medición de la Producción del Habla/estadística & datos numéricos , Accidente Cerebrovascular/complicacionesRESUMEN
PURPOSE: The purpose of this study was to develop a short form of the Boston Naming Test (BNT; Kaplan, Goodglass, & Weintraub, 2001) for individuals with aphasia and compare it with 2 existing short forms originally analyzed with responses from people with dementia and neurologically healthy adults. METHOD: Development of the new BNT-Aphasia Short Form and analysis of the other 2 forms were completed with archival data from 100 individuals with aphasia. The authors developed the BNT-Aphasia Short Form using items from the original 60-item instrument based on item response theory. Rasch analysis was computed on the short forms developed by Graves, Bezeau, Fogarty, and Blair (2004) and by Mack, Freed, Williams, and Henderson (1992). RESULTS: Analysis of the Graves et al. (2004) short form resulted in the smallest range of item difficulty and the largest floor effect compared with the Mack et al. (1992) short form and the BNT-Aphasia short form. The BNT-Aphasia Short Form showed an increase in information in the middle of the scale relative to both the Graves et al. and the Mack et al. forms. CONCLUSIONS: The new short form demonstrates good psychometric properties when used with individuals with aphasia. However, the Mack et al. form proved to be as psychometrically sound as the BNT-Aphasia Short Form and is also appropriate for individuals with aphasia.
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Anomia/diagnóstico , Afasia/diagnóstico , Demencia/diagnóstico , Pruebas Neuropsicológicas , Anciano , Anomia/complicaciones , Afasia/complicaciones , Estudios de Casos y Controles , Discriminación en Psicología , Humanos , Psicometría , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Changes in brain activity characterizing impaired speech production after brain damage have usually been investigated by comparing aphasic speakers with healthy subjects because prestroke data are normally not available. However, when interpreting the results of studies of stroke patients versus healthy controls, there is an inherent difficulty in disentangling the contribution of neuropathology from other sources of between-subject variability. In the present work, we had an unusual opportunity to study an aphasic patient with severe anomia who had incidentally performed a picture naming task in an ERP study as a control subject one year before suffering a left hemisphere stroke. The fortuitous recording of this patient's brain activity before his stroke allows direct comparison of his pre- and poststroke brain activity in the same language production task. The subject did not differ from other healthy subjects before his stroke, but presented major electrophysiological differences after stroke, both in comparison to himself before stroke and to the control group. ERP changes consistently appeared after stroke in a specific time window starting about 250 msec after picture onset, characterized by a single divergent but stable topographic configuration of the scalp electric field associated with a cortical generator abnormally limited to left temporal posterior perilesional areas. The patient's pattern of anomia revealed a severe lexical-phonological impairment and his ERP responses diverged from those of healthy controls in the time window that has previously been associated with lexical-phonological processes during picture naming. Given that his prestroke ERPs were indistinguishable from those of healthy controls, it seems highly likely that the change in his poststroke ERPs is due to changes in language production processes as a consequence of stroke. The patient's neurolinguistic deficits, combined with the ERPs results, provide unique evidence for the role of left temporal cortex in lexical-phonological processing from about 250 to 450 msec during word production.
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Afasia de Broca/etiología , Mapeo Encefálico , Potenciales Evocados Auditivos/fisiología , Estadística como Asunto , Accidente Cerebrovascular/complicaciones , Vocabulario , Estimulación Acústica/métodos , Anciano , Anomia/complicaciones , Afasia de Broca/patología , Distribución de Chi-Cuadrado , Electroencefalografía/métodos , Lateralidad Funcional/fisiología , Humanos , Masculino , Psicolingüística/métodos , Análisis EspectralRESUMEN
The intensity of aphasia therapy has been a key clinical question. The aim of this case-series study was to compare the outcome of intensive and non-intensive therapy in the relearning of words for people with aphasia. Eight participants took part in a study comparing the intensity of delivery of the therapy. Participants received two courses of the same therapy (each lasting 10 sessions) delivered either intensively or non-intensively. Therapy consisted of confrontation naming with progressive phonemic and orthographic cues. Post-therapy assessments were carried out immediately after the study and one month later. Performance was also monitored during each therapy session. Immediately post-therapy, both types of therapy had improved naming accuracy considerably and there was no significant difference between the two interventions. One month later, seven out of eight participants showed a small yet significant difference in naming accuracy, favouring non-intensive over intense therapy. There were no differences in the learning patterns during the therapy sessions between the intensive and non-intensive therapies. For the majority of people with aphasia post-stroke, both intense and non-intense therapy for anomia leads to improved naming performance. Retention at one-month post therapy is relatively superior after non-intensive therapy.
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Anomia/terapia , Terapia del Lenguaje/métodos , Rehabilitación de Accidente Cerebrovascular , Anomia/complicaciones , Femenino , Humanos , Aprendizaje , Masculino , Persona de Mediana Edad , Desempeño PsicomotorRESUMEN
BACKGROUND AND PURPOSE: Recent research suggests that increased left hemisphere cortical activity, primarily of the left frontal cortex, is associated with improved naming performance in stroke patients with aphasia. Our aim was to determine whether anodal transcranial direct-current stimulation (tDCS), a method thought to increase cortical excitability, would improve naming accuracy in stroke patients with aphasia when applied to the scalp overlying the left frontal cortex. METHODS: Ten patients with chronic stroke-induced aphasia received 5 days of anodal tDCS (1 mA for 20 minutes) and 5 days of sham tDCS (for 20 minutes, order randomized) while performing a computerized anomia treatment. tDCS positioning was guided by a priori functional magnetic resonance imaging results for each individual during an overt naming task to ensure that the active electrode was placed over structurally intact cortex. RESULTS: Results revealed significantly improved naming accuracy of treated items (F[1,9]=5.72, P<0.040) after anodal tDCS compared with sham tDCS. Patients who demonstrated the most improvement were those with perilesional areas closest to the stimulation site. Crucially, this treatment effect persisted at least 1 week after treatment. CONCLUSIONS: Our findings suggest that anodal tDCS over the left frontal cortex can lead to enhanced naming accuracy in stroke patients with aphasia and, if proved to be effective in larger studies, may provide a supplementary treatment approach for anomia.
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Anomia/terapia , Afasia/terapia , Terapia por Estimulación Eléctrica , Lóbulo Frontal , Accidente Cerebrovascular/terapia , Anciano , Anciano de 80 o más Años , Anomia/complicaciones , Afasia/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inducción de Remisión , Accidente Cerebrovascular/complicaciones , Factores de TiempoRESUMEN
Different forms of anomia are observed in aphasia, which can be related to impaired semantic, lexical or phonological processes. In the present study, we analysed electrophysiological correlates of different patterns of anomia in six aphasic speakers. Event-related potentials (ERPs) were recorded during picture naming in each anomic speaker and in 15 healthy controls. Waveform analysis and temporal segmentation indicated a difference between high and low frequency words in the control group between 270 and 330 msec after picture onset. The ERPs recorded in the patients were compared to the control group. The time-windows of divergent ERP correlates were very similar between successful and erroneous naming, but they were differently distributed in the 6 patients. Two patients with conduction aphasia and impaired phonological encoding had normal electro-cortical activity during the first 300 msec and abnormal patterns between 300 and 450 msec. Two patients with lexical-semantic impairment had earlier ERP abnormalities starting immediately after visual processes. The two patients with less severe anomia and preponderance of omission errors displayed abnormal ERPs between 280 and 350 msec. These results indicate that abnormal electro-cortical correlates of anomic profiles can be observed in different time-windows, which seem to correspond to the time course of the impaired encoding processes.