ABSTRACT
OBJECTIVES: We aimed to examine the effects of multisite anodal transcranial direct current stimulation (tDCS) combined with cognitive stimulation (CS) over 2 months on cognitive performance and brain activity, and the relationship between them, in patients with Alzheimer's disease (AD). METHODS: Patients with AD were randomly assigned to an active tDCS+CS (n=18) or a sham tDCS+CS (n=18) group. Cognitive performance was assessed using the Alzheimer Disease Assessment Scale-cognitive subscale (ADAS-cog) and brain activity using EEG (spectral power and coherence analysis) before and after the intervention. Multisite anodal tDCS (2 mA, 30 min) was applied over six brain regions [left and right dorsolateral prefrontal cortex (F3 and F4), Broca's area (F5), Wernicke's area (CP5), left and right somatosensory association cortex (P3 and P4)] for 24 sessions (three times a week). Both groups performed CS during tDCS. RESULTS: Anodal tDCS+CS delays cognitive decline (ADAS-cog change) to a greater extent than sham tDCS+CS (-3.4±1.1 vs. -1.7±0.4; p=.03). Bilateral EEG coherence at high and low frequencies was greater for the active tDCS+CS than sham+CS group for most electrode pairs assessed (p < .05). The post-intervention ADAS-cog change score was predictive for EEG coherence at different sites (R²=.59 to .68; p < .05) in the active but not in the sham tDCS+CS group. CONCLUSION: Anodal tDCS+CS improved overall cognitive function and changed EEG brain activity compared to sham tDCS+CS. Changes in cognitive performance were associated with changes in EEG measures of brain activity. Anodal tDCS+CS appears to be a promising therapeutic strategy to modulate cortical activity and improve cognitive function in patients with AD.
Subject(s)
Alzheimer Disease , Transcranial Direct Current Stimulation , Alzheimer Disease/therapy , Cognition , Double-Blind Method , Electrodes , Humans , Prefrontal Cortex/physiologyABSTRACT
PURPOSE: To compare coreferential processing in elderly people with and without Alzheimer's disease in Brazilian Portuguese. METHODS: Twelve elderly people without Alzheimer's (EA) and six elderly people with Alzheimer's disease (EWA) participated in the study. The Mini-Mental State Examination was used for cognitive screening of participants. Two experiments were performed using the self-monitored reading technique to analyze coreference processing. Each contained eight experimental phrases and 24 distracting phrases, one of them using repeated pronouns and names and the other using hyponyms and hypernyms. After reading, questions were asked related to the content of the sentences. The main variable of interest was reading time, measured after the presentation of anaphoric resuming. RESULTS: In the first experiment, there were statistically significant results. The EA group processed the pronouns more quickly than repeated names. The volunteers of the EWA group were quicker in resuming repeated names. In the second experiment, the results show that the EA group showed preference for hypernyms in anaphoric resumption, whereas the EWA group did not present significant differences between conditions. CONCLUSION: Elderly people without pathology processed pronouns and hypernyms more quickly compared to retrievals with repeated names and hyponyms, respectively, due to the smaller amount of semantic traits necessary to identify the antecedents in those conditions, as well as syntactic and discursive prominence. Elderly people with AD read names more readily than pronouns. There was no difference in anaphoric processing involving hyponyms and hypernyms, which may result from impaired working memory.
OBJETIVO: Comparar o processamento correferencial, em idosos com e sem a Doença de Alzheimer, no Português Brasileiro. MÉTODO: Participaram 12 idosos sem Alzheimer (ISA), e 06 idosos com a Doença de Alzheimer (IDA). O Mini-Exame do Estado Mental foi utilizado para triagem cognitiva dos participantes. Dois experimentos foram realizados utilizando a técnica de leitura automonitorada para analisar o processamento da correferência, cada um contendo oito frases experimentais e 24 frases distratoras, um deles utilizou pronomes e nomes repetidos, já o outro utilizou hipônimos e hiperônimos. Após a leitura, foram realizadas perguntas relacionadas ao conteúdo das frases. A principal variável de interesse foi o tempo de leitura aferido após a apresentação das retomadas anafóricas. RESULTADOS: No primeiro experimento, foram encontrados resultados estatisticamente significantes, no grupo ISA os pronomes foram processados mais rapidamente do que nomes repetidos, e no grupo IDA, os voluntários foram mais rápidos na retomada do nome repetido. No segundo experimento, os resultados demonstraram que o grupo ISA apresentou preferência, na retomada anafórica, pelos hiperônimos, já o grupo IDA não apresentou diferenças significativas entre as condições. CONCLUSÃO: Os idosos sem patologia processaram mais rapidamente pronomes e hiperônimos, quando comparados a retomadas com nomes repetidos e hipônimos, respectivamente, pela menor quantidade de traços semânticos necessários para identificar os antecedentes naquelas condições, assim como pela proeminência sintática e discursiva. Nos idosos com DA, os nomes foram lidos mais prontamente que pronomes, e não houve diferença no processamento anafórico envolvendo hipônimos e hiperônimos, podendo decorrer do comprometimento na memória de trabalho.
Subject(s)
Alzheimer Disease , Aged , Brazil , Humans , Language , Memory Disorders , SemanticsABSTRACT
RESUMO Objetivo Comparar o processamento correferencial, em idosos com e sem a Doença de Alzheimer, no Português Brasileiro. Método Participaram 12 idosos sem Alzheimer (ISA), e 06 idosos com a Doença de Alzheimer (IDA). O Mini-Exame do Estado Mental foi utilizado para triagem cognitiva dos participantes. Dois experimentos foram realizados utilizando a técnica de leitura automonitorada para analisar o processamento da correferência, cada um contendo oito frases experimentais e 24 frases distratoras, um deles utilizou pronomes e nomes repetidos, já o outro utilizou hipônimos e hiperônimos. Após a leitura, foram realizadas perguntas relacionadas ao conteúdo das frases. A principal variável de interesse foi o tempo de leitura aferido após a apresentação das retomadas anafóricas. Resultados No primeiro experimento, foram encontrados resultados estatisticamente significantes, no grupo ISA os pronomes foram processados mais rapidamente do que nomes repetidos, e no grupo IDA, os voluntários foram mais rápidos na retomada do nome repetido. No segundo experimento, os resultados demonstraram que o grupo ISA apresentou preferência, na retomada anafórica, pelos hiperônimos, já o grupo IDA não apresentou diferenças significativas entre as condições. Conclusão Os idosos sem patologia processaram mais rapidamente pronomes e hiperônimos, quando comparados a retomadas com nomes repetidos e hipônimos, respectivamente, pela menor quantidade de traços semânticos necessários para identificar os antecedentes naquelas condições, assim como pela proeminência sintática e discursiva. Nos idosos com DA, os nomes foram lidos mais prontamente que pronomes, e não houve diferença no processamento anafórico envolvendo hipônimos e hiperônimos, podendo decorrer do comprometimento na memória de trabalho.
ABSTRACT Purpose To compare coreferential processing in elderly people with and without Alzheimer's disease in Brazilian Portuguese. Methods Twelve elderly people without Alzheimer's (EA) and six elderly people with Alzheimer's disease (EWA) participated in the study. The Mini-Mental State Examination was used for cognitive screening of participants. Two experiments were performed using the self-monitored reading technique to analyze coreference processing. Each contained eight experimental phrases and 24 distracting phrases, one of them using repeated pronouns and names and the other using hyponyms and hypernyms. After reading, questions were asked related to the content of the sentences. The main variable of interest was reading time, measured after the presentation of anaphoric resuming. Results In the first experiment, there were statistically significant results. The EA group processed the pronouns more quickly than repeated names. The volunteers of the EWA group were quicker in resuming repeated names. In the second experiment, the results show that the EA group showed preference for hypernyms in anaphoric resumption, whereas the EWA group did not present significant differences between conditions. Conclusion Elderly people without pathology processed pronouns and hypernyms more quickly compared to retrievals with repeated names and hyponyms, respectively, due to the smaller amount of semantic traits necessary to identify the antecedents in those conditions, as well as syntactic and discursive prominence. Elderly people with AD read names more readily than pronouns. There was no difference in anaphoric processing involving hyponyms and hypernyms, which may result from impaired working memory.
