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1.
J Neurosci ; 40(25): 4925-4935, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32409620

RESUMO

To identify the neural correlates of perceptual awareness, researchers often compare the differences in neural activation between conditions in which an observer is or is not aware of a stimulus. While intuitive, this approach often contains a critical limitation: to link brain activity with perceptual awareness, observers traditionally report the contents of their perceptual experience. However, relying on observers' reports is problematic because it is difficult to know whether the neural responses being measured are associated with conscious perception or with postperceptual processes involved in the reporting task (e.g., working memory, decision-making). To address this issue, we combined a standard visual masking paradigm with a recently developed "no-report" paradigm in male/female human participants. In the visual masking paradigm, observers saw images of animals and objects that were visible or invisible, depending on their proximity to masks. Meanwhile, on half of the trials, observers reported the contents of their perceptual experience (i.e., report condition), while on the other half of trials they refrained from reporting about their experiences (i.e., no-report condition). We used electroencephalography to examine how visibility interacts with reporting by measuring the P3b event-related potential, one of the proposed canonical "signatures" of conscious processing. Overall, we found a robust P3b in the report condition, but no P3b whatsoever in the no-report condition. This finding suggests that the P3b itself is not a neural signature of conscious processing and highlights the importance of carefully distinguishing the neural correlates of perceptual awareness from postperceptual processing.SIGNIFICANCE STATEMENT What are the neural signatures that differentiate conscious and unconscious processing in the brain? Perhaps the most well established candidate signature is the P3b event-related potential, a late slow wave that appears when observers are aware of a stimulus, but disappears when a stimulus fails to reach awareness. Here, however, we found that the P3b does not track what observers are perceiving, but instead tracks what observers are reporting. When observers are aware of simple visual stimuli, the P3b is nowhere to be found unless observers are reporting the contents of their experience. These results challenge the well established notion of the P3b as a neural marker of awareness and highlight the need for new approaches to the neuroscience of consciousness.


Assuntos
Conscientização/fisiologia , Encéfalo/fisiologia , Potencial Evocado P300/fisiologia , Mascaramento Perceptivo/fisiologia , Percepção Visual/fisiologia , Adulto , Estado de Consciência/fisiologia , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
2.
Sci Rep ; 10(1): 8452, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439995

RESUMO

Patients in the transition from locked-in (i.e., a state of almost complete paralysis with voluntary eye movement control, eye blinks or twitches of face muscles, and preserved consciousness) to complete locked-in state (i.e., total paralysis including paralysis of eye-muscles and loss of gaze-fixation, combined with preserved consciousness) are left without any means of communication. An auditory communication system based on electrooculogram (EOG) was developed to enable such patients to communicate. Four amyotrophic lateral sclerosis patients in transition from locked-in state to completely locked-in state, with ALSFRS-R score of 0, unable to use eye trackers for communication, learned to use an auditory EOG-based communication system. The patients, with eye-movement amplitude between the range of ±200µV and ±40µV, were able to form complete sentences and communicate independently and freely, selecting letters from an auditory speller system. A follow-up of one year with one patient shows the feasibility of the proposed system in long-term use and the correlation between speller performance and eye-movement decay. The results of the auditory speller system have the potential to provide a means of communication to patient populations without gaze fixation ability and with low eye-movement amplitude range.


Assuntos
Esclerose Amiotrófica Lateral/reabilitação , Comunicação , Eletroculografia/métodos , Potencial Evocado P300/fisiologia , Movimentos Oculares/fisiologia , Fixação Ocular/fisiologia , Paralisia/reabilitação , Adulto , Esclerose Amiotrófica Lateral/psicologia , Auxiliares de Comunicação para Pessoas com Deficiência , Condicionamento Psicológico , Potenciais Evocados Auditivos , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Paralisia/psicologia , Transferência de Pacientes
3.
Int. j. morphol ; 38(2): 356-362, abr. 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1056447

RESUMO

El suicidio es un problema de salud a nivel mundial, siendo la conducta suicida uno de los predictores de mortalidad por suicidio; sin embargo, su valoración aún sigue siendo compleja. Aunque la cantidad de literatura que ha abordado distintas perspectivas de la conducta suicida es abundante, se requiere ahondar en nuevos métodos que permitan una valoración rápida y objetiva de ésta, proporcionando a los clínicos y pacientes, un sistema de evaluación que registre los cambios de estados emocionales de manera dinámica. El objetivo de este manuscrito fue proporcionar una visión general de la morfología de los potenciales evocados auditivos de latencia tardía p300 y su rol en la evaluación de la conducta suicida.


Suicide is a global health problem, with suicidal behavior being one of the predictors of suicide mortality; however, its assessment is still complex. Although the amount of literature that has addressed different perspectives of suicidal behavior is abundant, it is necessary to deepen new methods that allow a rapid and objective assessment of it, providing clinicians and patients with an evaluation system that allows changes in emotional state to be recorded dynamically. The aim of this manuscript was to provide an overview of morphological patterns of auditory evoked potential P300 latency late in the assessment of suicidal behavior.


Assuntos
Comportamento do Adolescente/fisiologia , Potencial Evocado P300/fisiologia , Ideação Suicida , Valores de Referência , Eletrofisiologia , Potenciais Evocados Auditivos/fisiologia
4.
Int J Neural Syst ; 30(3): 2050009, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32116091

RESUMO

Traditional training methods need to collect a large amount of data for every subject to train a subject-specific classifier, which causes subjects fatigue and training burden. This study proposes a novel training method, TrAdaBoost based on cross-validation and an adaptive threshold (CV-T-TAB), to reduce the amount of data required for training by selecting and combining multiple subjects' classifiers that perform well on a new subject to train a classifier. This method adopts cross-validation to extend the amount of the new subject's training data and sets an adaptive threshold to select the optimal combination of the classifiers. Twenty-five subjects participated in the N200- and P300-based brain-computer interface. The study compares CV-T-TAB to five traditional training methods by testing them on the training of a support vector machine. The accuracy, information transfer rate, area under the curve, recall and precision are used to evaluate the performances under nine conditions with different amounts of data. CV-T-TAB outperforms the other methods and retains a high accuracy even when the amount of data is reduced to one-third of the original amount. The results imply that CV-T-TAB is effective in improving the performance of a subject-specific classifier with a small amount of data by adopting multiple subjects' classifiers, which reduces the training cost.


Assuntos
Interfaces Cérebro-Computador , Córtex Cerebral/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Neurorretroalimentação/fisiologia , Máquina de Vetores de Suporte , Adulto , Interfaces Cérebro-Computador/normas , Eletroencefalografia/normas , Potencial Evocado P300/fisiologia , Humanos
5.
Acta Psychol (Amst) ; 205: 103058, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32199246

RESUMO

In this study we evaluate how cognitive load affects susceptibility to auditory signals. Previous research has used the frontal P3 (fP3) event related potential response to auditory novel stimuli as an index for susceptibility to auditory signals. This work demonstrated that tasks that induce cognitive load such as visual and manual tasks, reduced susceptibility. It is however unknown whether cognitive load without visual or manual components also reduces susceptibility. To investigate this, we induced cognitive load by means of the verb generation task, in which participants need to think about a verb that matches a noun. The susceptibility to auditory signals was measured by recording the event related potential in response to a successively presented oddball probe stimulus at 3 different inter-stimulus intervals, 0 ms, 200 ms or 400 ms after the offset of the noun from the verb generation task. An additional control baseline condition, in which oddball response was probed without a verb generation task, was also included. Results show that the cognitive load associated with the verb task reduces fP3 response (and associated auditory signal susceptibility) compared to baseline, independent of presentation interval. This suggests that not only visual and motor processing, but also cognitive load without visual or manual components, can reduce susceptibility to auditory signals and alerts.


Assuntos
Percepção Auditiva/fisiologia , Cognição/fisiologia , Potencial Evocado P300/fisiologia , Estimulação Acústica/métodos , Adulto , Eletroencefalografia/métodos , Feminino , Lobo Frontal/fisiologia , Humanos , Masculino , Tempo de Reação/fisiologia , Semântica , Análise e Desempenho de Tarefas , Adulto Jovem
6.
Muscle Nerve ; 61(6): 702-707, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32034787

RESUMO

A brain-computer interface (BCI) is a device that detects signals from the brain and transforms them into useful commands. Researchers have developed BCIs that utilize different kinds of brain signals. These different BCI systems have differing characteristics, such as the amount of training required and the degree to which they are or are not invasive. Much of the research on BCIs to date has involved healthy individuals and evaluation of classification algorithms. Some BCIs have been shown to have potential benefit for users with minimal muscular function as a result of amyotrophic lateral sclerosis. However, there are still several challenges that need to be successfully addressed before BCIs can be clinically useful.


Assuntos
Esclerose Amiotrófica Lateral/fisiopatologia , Esclerose Amiotrófica Lateral/reabilitação , Interfaces Cérebro-Computador/tendências , Encéfalo/fisiologia , Eletroencefalografia/métodos , Potencial Evocado P300/fisiologia , Humanos
7.
J Neurosci ; 40(11): 2305-2313, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32001610

RESUMO

Humans actively sample their environment with saccadic eye movements to bring relevant information into high-acuity foveal vision. Despite being lower in resolution, peripheral information is also available before each saccade. How the pre-saccadic extrafoveal preview of a visual object influences its post-saccadic processing is still an unanswered question. The current study investigated this question by simultaneously recording behavior and fixation-related brain potentials while human subjects made saccades to face stimuli. We manipulated the relationship between pre-saccadic "previews" and post-saccadic images to explicitly isolate the influences of the former. Subjects performed a gender discrimination task on a newly foveated face under three preview conditions: scrambled face, incongruent face (different identity from the foveated face), and congruent face (same identity). As expected, reaction times were faster after a congruent-face preview compared with a scrambled-face preview. Importantly, intact face previews (either incongruent or congruent) resulted in a massive reduction of post-saccadic neural responses. Specifically, we analyzed the classic face-selective N170 component at occipitotemporal electroencephalogram electrodes, which was still present in our experiments with active looking. However, the post-saccadic N170 was strongly attenuated following intact-face previews compared with the scrambled condition. This large and long-lasting decrease in evoked activity is consistent with a trans-saccadic mechanism of prediction that influences category-specific neural processing at the start of a new fixation. These findings constrain theories of visual stability and show that the extrafoveal preview methodology can be a useful tool to investigate its underlying mechanisms.SIGNIFICANCE STATEMENT Neural correlates of object recognition have traditionally been studied by flashing stimuli to the central visual field. This procedure differs in fundamental ways from natural vision, where viewers actively sample the environment with eye movements and also obtain a low-resolution preview of soon-to-be-fixated objects. Here we show that the N170, a classic electrophysiological marker of the structural encoding of faces, also occurs during a more natural viewing condition but is strongly reduced due to extrafoveal preprocessing (preview benefit). Our results therefore highlight the importance of peripheral vision during trans-saccadic processing in building a coherent and stable representation of the world around us.


Assuntos
Reconhecimento Facial/fisiologia , Fixação Ocular/fisiologia , Movimentos Sacádicos/fisiologia , Adulto , Cor , Sinais (Psicologia) , Eletroencefalografia , Potencial Evocado P300/fisiologia , Potenciais Evocados Visuais/fisiologia , Feminino , Identidade de Gênero , Humanos , Masculino , Lobo Occipital/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação , Lobo Temporal/fisiologia , Adulto Jovem
8.
Braz. j. otorhinolaryngol. (Impr.) ; 86(1): 119-126, Jan.-Feb. 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1089359

RESUMO

Abstract Introduction Tinnitus is sound perception in the absence of a sound source. Changes in parameters of latency and amplitude on the auditory event related potentials or long latency potentials waves have been cited in tinnitus patients when compared to a control group. Objective To perform an assessment of scientific evidence that verifies the possibility of alterations in latency or amplitude of the waves of event related potentials in individuals with tinnitus. Methods By using SciELO, Lilacs, ISI Web and PubMed, scientific databases, a review was performed. Articles published in English, Portuguese, French and Spanish that correlated tinnitus with changes in event related potentials were included in this review. Results Twelve articles were located, however only eight fulfilled the criteria for inclusion. Conclusion The sample of selected studies demonstrate that the long latency auditory evoked potentials related to events between the control and tinnitus patients showed some changes in latency and or amplitude in tinnitus patients. There are changes in event-related potentials when comparing patients with tinnitus and the control group. These changes take place considering the severity of tinnitus, tinnitus site of lesion, and capacity for changes after interventions. The event related potentials can help to determine the neurotransmitter involved in tinnitus generation and evaluate tinnitus treatments.


Resumo Introdução O zumbido é a percepção de um som na ausência de uma fonte sonora. Mudanças nos parâmetros de latência e amplitude nas ondas dos potenciais evocados auditivos relacionados a eventos ou potenciais de longa latência foram citadas em pacientes com zumbido quando comparados a um grupo controle. Objetivo Realizar uma avaliação de evidências científicas que verifiquem a possibilidade de alterações na latência ou amplitude das ondas de potenciais evocados auditivos relacionados a eventos em indivíduos com zumbido. Método Foi feita uma revisão a partir dos bancos de dados científicos SciELO, Lilacs, ISI Web e PubMed. Artigos publicados em inglês, português, francês e espanhol que correlacionavam zumbido com alterações nos potenciais evocados auditivos relacionados a eventos foram incluídos. Resultados Foram localizados 12 artigos, porém apenas oito preencheram os critérios de inclusão. Conclusão A amostra de estudos selecionados demonstra que os potenciais evocados auditivos de longa latência relacionados a eventos entre os pacientes-controle e com zumbido apresentaram algumas alterações na latência e/ou amplitude nos pacientes com zumbido. Há mudanças nos potenciais relacionados a eventos ao comparar pacientes com zumbido e o grupo controle. Essas alterações consideram a gravidade do zumbido, o local da lesão do zumbido e a capacidade de alterações após as intervenções. Os potenciais evocados auditivos relacionados a eventos podem ajudar a determinar o neurotransmissor envolvido na geração do zumbido e avaliar os tratamentos para o zumbido.


Assuntos
Humanos , Zumbido/fisiopatologia , Potenciais Evocados/fisiologia , Potenciais Evocados Auditivos/fisiologia , Atenção , Zumbido/psicologia , Potencial Evocado P300/fisiologia , Medicina Baseada em Evidências
9.
Cogn Process ; 21(2): 253-260, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31953643

RESUMO

Several studies have explored the differentiation of visual action verbs (e.g., see, perceive, and notice). The vast number and variety to choose from, along with a common understanding between the meanings of the words, suggests that they may represent measurable differences in perceptual processing. The present study investigated how manipulating the visual action verb embedded into a common instruction could produce either differentiable electrophysiological or behavioral effects, or possibly both. It was hypothesized that the P300 component elicited during an oddball task would differ depending on the visual action that participants had been instructed to perform. Results support this hypothesis, but suggest that response bias also could contribute to action performance. When participants were asked to 'sense' deviants in an oddball task, the P300 differed in amplitude compared to when they were asked to 'distinguish' the deviants. In addition, participants displayed varying response times for the instructions 'notice' versus 'view', 'distinguish' versus 'sense', and 'notice' versus 'sense'. When considering the behavioral and ERP results together, we can conclude that response biases and perceptual cognitive processing both contribute to how identical stimuli can be processed depending on the visual action performed.


Assuntos
Potencial Evocado P300/fisiologia , Processos Mentais/fisiologia , Tempo de Reação/fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
10.
Int J Psychophysiol ; 148: 59-66, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31904394

RESUMO

Previous research (Herring et al., 2011) indicated that certain types of incongruent verbal priming enhance responding to the subsequent (primed) stimuli. By priming participants in a P300-based Concealed Information Test (CIT), we examined the possible enhancement effects of priming stimuli in the P300 based Complex Trial Protocol (CTP) for face recognition. Participants were divided into two groups: one group with priming and one control group without. The probe (Pr) and irrelevants (Iall) of the two groups were faces, namely, pictures of the actor Tom Cruise (Pr) and of other unknown faces (Iall). One group had priming before Pr/Iall and one control group had no priming. The priming group was called the non-identical priming (NIP) group in which the verbal priming item (the name, "Bill Smith") is identical with neither Pr nor any of the Ialls. The group without priming is the control group which is called the non-priming group (NP) that simply experiences the basic Complex Trial Protocol. Results were that non-identical priming produced larger CIT effects than the control group, which is consistent with earlier findings. Also, the amplitude of the probe of the NIP group is larger than that of the NP group, while their irrelevants didn't show any significant difference. This means that the incongruent verbal priming did enhance the P300 CIT effect for the probe, which could further improve the accuracy of CTP for the concealed information test.


Assuntos
Associação , Córtex Cerebral/fisiologia , Potencial Evocado P300/fisiologia , Reconhecimento Facial/fisiologia , Adolescente , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Projetos de Pesquisa , Adulto Jovem
11.
Brain Cogn ; 138: 105508, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31838302

RESUMO

To determine the neuroelectric underpinnings of exercise-induced changes in working memory, this study investigated the acute effects ofaerobic exercise (AE) on the P3 component of an event-related potential and brain oscillations during a serial n-back task. Task-related electroencephalography was collected in 23 young adults following 20 min of rest and AE on separate, counterbalanced days. The results revealed reductions in standard deviation of response time and coefficient of variation of response time following AE compared to rest. Neuroelectric analyses showed increased P3 amplitude following AE compared to rest. Task-related frontal alpha desynchronization was stronger in the 2-back compared with the 1-back task following AE, while no such modulation was observed following rest. These findings suggest AE may temporarily enhance working memory, as reflected by decreases in response variability, which are accompanied by neuroelectric indices reflecting greater upregulation of attentional processes.


Assuntos
Ritmo alfa/fisiologia , Atenção/fisiologia , Sincronização Cortical/fisiologia , Potencial Evocado P300/fisiologia , Exercício Físico/fisiologia , Memória de Curto Prazo/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Ritmo Teta/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
12.
Int J Psychophysiol ; 147: 113-127, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31778726

RESUMO

Data from three published studies examining autonomic and ERP measures in variants of a dishabituation paradigm were re-analysed to clarify ambiguous novelty results. The three studies manipulated 1. Novelty, 2. Novelty and Intensity, and 3. Novelty and Significance, in auditory dishabituation paradigms at very long interstimulus intervals (ISIs). The question of whether any single ERP matches SCR as the benchmark for the phasic Orienting Reflex (OR) was also addressed. Finally, we aimed to align the re-analysed measures of this and the previous analyses with processes of Preliminary Process Theory (PPT). The SCR demonstrated decrement, recovery, and dishabituation. A summary temporal PCA extracted PN (Processing Negativity), P3a, P3b, Novelty P3, and classic SW for detailed analysis. P3b and SW showed decrement but no recovery at the change trial, while Respiratory pause (RP) and Novelty P3 demonstrated decrement and recovery, but no dishabituation. Post hoc exploration of observed power versus sample size for each of these findings confirmed their robustness. No decrement for PN was also confirmed. Five autonomic and ERP groupings emerged and aligned with modules of processing in PPT: ECR1 (cardiac deceleration), P1, N1-3, and PN - stimulus registration; RP and Novelty P3 - Novelty registration; Peripheral Vasoconstriction (PVC) and P3b - Intensity registration; and ECR2 (cardiac acceleration) and classic SW - Response system. The SCR was confirmed as the sole index of the phasic OR. The pattern of results for the Late Positive Complex (LPC) components (P3a, P3b, Novelty P3, and SW) suggests each is differentially sensitivity to selective determinants of the phasic OR, and consequently the summary LPC is presented as the most appropriate central index of the phasic OR.


Assuntos
Percepção Auditiva/fisiologia , Sistema Nervoso Autônomo/fisiologia , Potenciais Evocados/fisiologia , Resposta Galvânica da Pele/fisiologia , Habituação Psicofisiológica/fisiologia , Orientação/fisiologia , Reflexo/fisiologia , Adolescente , Adulto , Eletroencefalografia , Potencial Evocado P300/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal , Adulto Jovem
13.
Int J Psychophysiol ; 148: 75-83, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31857192

RESUMO

To establish a trait-dispositional variable as an indicator of liability for the development of substance use disorders (SUDs), the trait must share heritable variance with SUDs and its association should not be primarily attributable to a direct impact of SUDs on characteristics that define the trait. The current work applied a co-twin control (CTC) modeling approach to data from two monozygotic twin samples to investigate the degree to which different measures of trait-impulsiveness represent indicants of vulnerability to SUDs (liability indicators), or outcomes or concomitants of SUDs (exposure indicators). The Five Factor Model (FFM) trait of conscientiousness was assessed via self-report, and a counterpart neurobehavioral trait of disinhibition was assessed both through self-report and using self-report and brain response measures combined. FFM trait data were available for one twin sample (N = 298); data for variants of P3 brain response were available along with a scale measure of disinhibition in the other (N = 258). CTC analyses revealed only an exposure effect of SUD symptomatology on FFM conscientiousness, indicating that this self-report assessed trait does not index liability for SUDs. By contrast, the disinhibition scale measure showed pronounced liability and weaker exposure-based associations with SUDs - and when quantified using scale scores together with P3 brain response, the exposure-based association was eliminated, such that this disinhibition measure related to SUD symptoms exclusively as a function of liability influences. These findings highlight a distinct advantage of quantifying traits in neurobehavioral terms - namely, the capacity to effectively index dispositional liability for psychopathological outcomes.


Assuntos
Suscetibilidade a Doenças , Potencial Evocado P300/fisiologia , Inibição Psicológica , Personalidade/fisiologia , Autocontrole , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Modelos Estatísticos , Projetos de Pesquisa , Adulto Jovem
14.
Int J Psychophysiol ; 148: 13-24, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31846631

RESUMO

OBJECTIVES: Excess adiposity increases risk for cognitive impairment. Consumption of avocado, a highly bioavailable source of the xanthophyll lutein, has been shown to improve retinal lutein accumulation and cognitive function. Thus, we evaluated the influence of avocado consumption on cognitive function and lutein status among adults with overweight and obesity using a randomized-controlled trial with matching design for pertinent study outcomes. METHODS: A cohort of 84 adults (25-45 years, 31 males) were randomized to a treatment group (N = 47) that received a 12-week daily meal with fresh Hass avocado or a control group (N = 37) that received an isocaloric meal (clinicaltrials.gov, NCT02740439). Serum lutein and macular pigment optical density (MPOD) were used to assess xanthophyll status. Attention and inhibition were assessed using the Flanker, Oddball and Nogo tasks with accompanying electroencephalographic (EEG) recording. RESULTS: Participants in the treatment group exhibited improvements in serum lutein and accuracy in the Flanker task. However, there were no relationships between performance and changes in lutein status, nor neuroelectric variables. No significant changes in MPOD were observed. CONCLUSION: Daily avocado intake over 12 weeks, after controlling for covariates, improved attentional inhibition and increased serum lutein concentrations among adults with overweight and obesity. However, the cognitive benefits were independent of changes in lutein concentrations. Additional work is necessary to determine non-carotenoid, or carotenoid interactive, mechanisms by which avocados may influence cognitive function.


Assuntos
Atenção/fisiologia , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Inibição Psicológica , Sobrepeso/dietoterapia , Sobrepeso/metabolismo , Persea , Desempenho Psicomotor/fisiologia , Adulto , Eletroencefalografia , Potencial Evocado P300/fisiologia , Feminino , Humanos , Luteína/sangue , Masculino , Pessoa de Meia-Idade , Obesidade/dietoterapia , Obesidade/metabolismo , Resultado do Tratamento , Xantofilas/metabolismo
15.
Int J Psychophysiol ; 147: 213-223, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31812457

RESUMO

In a P300-based concealed information test (CIT), an increased response to a crime-related "probe" item of interest suggests concealed knowledge. Because the CIT's detection ability is based on knowledgeable parties recognizing the key item, weakening the crime memory might decrease probe identifiability and reduce diagnostic power. Research on retroactive memory interference (RI) has shown that acquiring new information after encoding a memory can degrade the original memory, which suggests that RI might pose a threat to CITs. To test this, Gronau et al. (2015) had participants complete a mock-crime, followed by either a control task or a RI manipulation task, intended to impair the crime memory. Both the simple guilty control and RI groups were subdivided into three time delay conditions: 1/3 of participants immediately completed the task and CIT, another 1/3 completed the task and returned a week later for the CIT, and the remaining participants completed both the task and CIT a week later. Results showed that RI reduced memory of crime details and skin conductance responses, while respiration line length was unaffected. Here, we extend Gronau et al. (2015), using the Complex Trial Protocol (CTP) version of the P300-based CIT, to investigate the influence of RI on recognition. The CIT effect was obvious in all six group × time delay subconditions, as evidenced by their significantly larger probe vs. irrelevant amplitudes, high percentage of bootstrapped iterations where probe > irrelevants, bootstrapped mean amplitude differences, and satisfactory hit rates. However, these indices of the CIT effect did not differ based on group or time delay, as was the case for target response error rates and P300 latencies. The only outcome of interest to vary by group or time delay was behavioral response times: both probe and combined irrelevant responses were delayed in the control (simple guilty) group. Thus, the evidence suggests that the RI manipulation used here does not threaten the P300-based CTP's accuracy. Results are considered as they compare to previous work, and limitations and possible explanations for our results are discussed.


Assuntos
Decepção , Potencial Evocado P300/fisiologia , Resposta Galvânica da Pele/fisiologia , Memória Episódica , Reconhecimento Psicológico/fisiologia , Adulto , Protocolos Clínicos , Eletroencefalografia , Humanos , Adulto Jovem
16.
Braz J Otorhinolaryngol ; 86(1): 119-126, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31753780

RESUMO

INTRODUCTION: Tinnitus is sound perception in the absence of a sound source. Changes in parameters of latency and amplitude on the auditory event related potentials or long latency potentials waves have been cited in tinnitus patients when compared to a control group. OBJECTIVE: To perform an assessment of scientific evidence that verifies the possibility of alterations in latency or amplitude of the waves of event related potentials in individuals with tinnitus. METHODS: By using SciELO, Lilacs, ISI Web and PubMed, scientific databases, a review was performed. Articles published in English, Portuguese, French and Spanish that correlated tinnitus with changes in event related potentials were included in this review. RESULTS: Twelve articles were located, however only eight fulfilled the criteria for inclusion. CONCLUSION: The sample of selected studies demonstrate that the long latency auditory evoked potentials related to events between the control and tinnitus patients showed some changes in latency and or amplitude in tinnitus patients. There are changes in event-related potentials when comparing patients with tinnitus and the control group. These changes take place considering the severity of tinnitus, tinnitus site of lesion, and capacity for changes after interventions. The event related potentials can help to determine the neurotransmitter involved in tinnitus generation and evaluate tinnitus treatments.


Assuntos
Potenciais Evocados Auditivos/fisiologia , Potenciais Evocados/fisiologia , Zumbido/fisiopatologia , Atenção , Potencial Evocado P300/fisiologia , Medicina Baseada em Evidências , Humanos , Zumbido/psicologia
17.
Biol Psychol ; 150: 107830, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31809767

RESUMO

The present study investigated individual differences modulating P300 and MFN amplitudes in a concealed information test (CIT). Some participants were offered candy and either denied (n = 41) or ate it (n = 31), while others witnessed an examiner eating it (informed condition; n = 34). Afterwards it was suggested that the candy was not meant for them. During the CIT, participants saw the candy (probe) and similar unknown items (irrelevants) and indicated that they did not know them. P300 and MFN amplitudes differed for probe and irrelevant items, revealing that known items were more salient and deception was accompanied by response conflicts. Larger differences between P300s for probe versus irrelevant items occurred for women. Furthermore, especially for women, response conflicts diminished when being in the informed condition. Different patterns of MFN amplitudes appeared for informed women depending on the Machiavellianism score, suggesting that gender and Machiavellianism could be related to different cognitive processing during deception.


Assuntos
Conflito Psicológico , Decepção , Potencial Evocado P300/fisiologia , Individualidade , Adulto , Eletroencefalografia , Feminino , Humanos , Maquiavelismo , Masculino , Fatores Sexuais , Adulto Jovem
18.
Neuroimage ; 204: 116243, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610297

RESUMO

Goal-directed behavior is affected by subliminally and consciously induced conflicts. Both seem to be modulated by catecholamines, especially dopamine. On the basis of cognitive theoretical and neurobiological considerations, we investigated the effects of dopamine D1 and D2 signaling with the help of unweighted polygenic scores in n = 207 healthy young human subjects. We used a task that combines subliminal primes with conscious flankers to induce conflicts. Dopamine D1 scores were formed based on DRD1 rs4532, CALY rs2298122 and TH rs10770141 single nucleotide polymorphisms (SNPs), while dopamine D2 scores were formed based on DRD2 rs6277 and NPY2R rs2234759 SNPs. We used EEG recordings and source localization analyses to identify differentially modulated neurophysiological sub-processes and functional neuroanatomical structures. Increased dopamine D1 signaling was associated with decreases in consciously induced conflicts. This decrease was due to enhanced stimulus-response mapping in the premotor cortex (BA6), as reflected by an increased P3 amplitude in incongruent trials. Attentional processes remained unaffected by dopamine D1 signaling. The effect of dopamine D2 signaling on conscious conflicts did not reach significance. Subliminally induced conflicts were neither modulated by dopamine D1, nor by dopamine D2 signaling. Our findings suggest that dopamine D1 signaling benefits consciously induced conflicts, presumably by improving the suppression of distracting information via gain control-initiated increases in top-down control processes associated with pre-motor regions. Dopamine D2 signaling does not seem to mediate behavioral differences. Probably, this is because the D2 state facilitates switching between (conflicting) top-down-selected mental representations, but not necessarily between top-down processes and bottom-up distractor information.


Assuntos
Atenção/fisiologia , Conflito Psicológico , Potencial Evocado P300/fisiologia , Função Executiva/fisiologia , Córtex Motor/fisiologia , Desempenho Psicomotor/fisiologia , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Transdução de Sinais/fisiologia , Adolescente , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Córtex Motor/metabolismo , Herança Multifatorial , Polimorfismo de Nucleotídeo Único , Receptores de Dopamina D1/genética , Receptores de Dopamina D2/genética , Estimulação Subliminar , Adulto Jovem
19.
Int J Psychophysiol ; 147: 1-8, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31697960

RESUMO

Temporary self-construal (independent vs. interdependent) priming can modulate the neural response to the reward for an individual. Our previous event-related potential (ERP) studies have indicated that people experience the rewards for a friend less strongly than they experience the same amount rewards for themselves. However, an issue remaining unclear is whether the ERP responses to rewards for a friend vary according to the way in which the self is construed. In the present study, we manipulated participants' self-construal (independent vs. interdependent) and found that independent self-construal priming resulted in a greater feedback-related negativity (FRN) in response to outcome feedback for oneself than for a friend during a monetary gambling task. In contrast, interdependent self-construal priming resulted in a comparable FRN in response to outcome feedback for oneself and for a friend. The P3 amplitude was insensitive to the self-construal manipulation. Our findings suggest that interdependent priming may result in comparable motivation elicited by rewards for participants themselves and for their friends. This study provides novel evidence that the neural response to rewards for friend varies according to the way in which the self is construed.


Assuntos
Ego , Potenciais Evocados/fisiologia , Amigos , Recompensa , Adulto , Eletroencefalografia , Potencial Evocado P300/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
20.
Clin EEG Neurosci ; 51(1): 19-33, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30997842

RESUMO

Brain-computer interfaces are sophisticated signal processing systems, which directly operate on neuronal signals to identify specific human intents. These systems can be applied to overcome certain disabilities or to enhance the natural capabilities of human beings. The visual P300 mind-speller is a prominent one among them, which has opened up tremendous possibilities in movement and communication applications. Today, there exist many state-of-the-art visual P300 mind-speller implementations in the literature as a result of numerous researches in this domain over the past 2 decades. Each of these systems can be evaluated in terms of performance metrics like classification accuracy, information transfer rate, and processing time. Various classification techniques associated with these systems, which include but are not limited to discriminant analysis, support vector machine, neural network, distance-based and ensemble of classifiers, have major roles in determining the overall system performances. The significance of a proper review on the recent developments in visual P300 mind-spellers with proper emphasis on their classification algorithms is the key insight for this work. This article is organized with a brief introduction to P300, concepts of visual P300 mind-spellers, the survey of literature with special focus on classification algorithms, followed by the discussion of various challenges and future directions.


Assuntos
Interfaces Cérebro-Computador , Auxiliares de Comunicação para Pessoas com Deficiência/psicologia , Potencial Evocado P300/fisiologia , Redes Neurais de Computação , Algoritmos , Humanos , Interface Usuário-Computador
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