Cognição e eletrofisiologia: uma revisão crítica das perspectivas nacionais

Abstract

ResumoA técnica eletrofisiológica Potenciais Relacionados ao Evento (PRE) vem sendo amplamente utilizada para o estudo da atividade cerebral correspondente a processos cognitivos específicos. O presente artigo apresenta uma revisão crítica dos estudos empregando PRE desenvolvidos em universidades brasileiras, enfatizando especialmente seus objetivos principais e abordagens metodológicas. Os estudos examinados investigaram efeitos eletrofisiológicos tradicionalmente reportados na literatura em PRE, como os efeitos denominados P300, N400 e MMN, proporcionando resultados relevantes teoricamente, bem como demonstrando a utilidade do PRE para a investigação de diversos temas de pesquisa. Possibilidades referentes a abordagens metodológicas alternativas para a análise dos PREs, assim como o emprego desta técnica no estudo de diversos processos psicológicos, são examinados e discutidos. Palavras-chave: Eletrofisiologia, Cognição, Neurociência. Cognition and electrophysiology: a critical review on the national perspectives AbstractThe electrophysiological technique Event-related potentials (ERP) has been widely employed in the study of brain activity reflecting specific cognitive processes. This current article presents a critical review of the ERP studies conducted in Brazilian universities, with special emphasis on their main goals and methodological approaches. The examined studies investigated electrophysiological effects traditionally reported in the ERP literature, as the P300, N400 and MMN effects, providing theoretically relevant results and demonstrating the usefulness of this technique for the investigation of several research topics. Possibilities concerning alternative methodological approaches on ERP analysis and the employment of this technique in the study of a variety of psychological processes are examined and discussed.

Potenciais evocados auditivos de longa latência em escolares com transtornos específicos de aprendizagem

“…Another parameter in the analysis of the results, is the amplitude, for it corresponds to the size of the electrical activity measured in microvolts (mV) (1) relating to the event or task involved in the response, preferably from the baseline of the record to the peak of the wave. P300 provides objective response on a cognitive task that requires attention, discrimination, recognition, perception and auditory memory, because the individual must recognize the characteristics and notice the variations of the presented stimuli, so it is possible to make a full assessment of the functioning of the auditory cortical system (1)(2)(3) . The learning of spoken and written language also depends on the incorporation of acoustic elements and the representation of the phonetic characteristics of a language, which makes LLAEP an important tool for assessing patients with language impairments and, thus, of great use in speech language pathology clinical practice.…”

Relationship between cognitive processing, language and verbal fluency among elderly individuals

“…The P300 wave is an event-related potential component that, when recorded by electroencephalography, surfaces as a positive deflection in voltage with a latency of approximately 300 ms after an auditory or visual stimulus is presented, the bioelectrical responses of which are related to attention, memory and decision-making 18 , 19. The P300 is mainly elicited using the oddball paradigm, in which participants are instructed to detect low-probability target items that occur randomly within a sequence of high-probability non-target items 20…”

“…Because the P300 is elicited by stimuli that require a high level of cognitive processing, it is considered one of the most promising electrophysiological tests for assessing dysfunctions and/or changes in the central nervous system and may be useful for early diagnosis of pathological cognitive changes. However, although P300 may be a promising instrument in terms of research, it has not yet gained wide acceptance in clinical or neuropsychological practice, because there is high variability in the values of latency and amplitude, making it impractical to use this technique for clinical and diagnostic purposes 20 - 22…”

Resolução temporal e potenciais corticais em diferentes níveis de proficiência da língua inglesa

“…A study investigated the interhemispheric differences related to amplitude and latency of the P3 30 , however, no significant results were found, which contradicts previously published data, according to which the amplitude of P3 is significantly greater than in the right hemisphere 31 .…”