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1.
Codas ; 31(4): e20180212, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31483042

RESUMO

This study aimed to measure the effects of a Computer-based Auditory Training Program (CBATP) on an adolescent diagnosed with Autism Spectrum Disorder (ASD) and Central Auditory Processing Disorder (CAPD). This is the case report of a male, 14-year-old adolescent diagnosed with ASD. The individual was submitted to basic audiological evaluation, central auditory processing assessment and hearing electrophysiology (EP), pre- and post-therapeutic intervention. Central auditory processing (CAP) was assessed by means of the following instruments: Time-compressed Speech Test (TCST), Random Gap Detection Test (RGDT), Staggered Spondaic Word Test (SSWT), Frequency (Pitch) Pattern Sequence Test (FPST), and Duration Pattern Test (DPT). The P300 component of the Event-related Potential (ERP) was used in the hearing EP. Pre-intervention assessment of CAP showed changes in the auditory skills of closure, figure-ground and temporal ordering, but normal temporal resolution ability. Post-intervention evaluation of CAP showed improvement in all previously mentioned auditory skills, except for the figure-ground ability, which remained unchanged. Regarding the findings of the hearing EP, a decrease in the latency of the P300 component was observed pre- and post-intervention. This study demonstrated that the use of a CBATP resulted in improvement in the hearing abilities assessed in an adolescent diagnosed with ASD.


Assuntos
Transtorno do Espectro Autista/complicações , Transtornos do Desenvolvimento da Linguagem/reabilitação , Adolescente , Transtorno do Espectro Autista/fisiopatologia , Potencial Evocado P300/fisiologia , Humanos , Transtornos do Desenvolvimento da Linguagem/etiologia , Transtornos do Desenvolvimento da Linguagem/fisiopatologia , Estudos Longitudinais , Masculino
2.
Sensors (Basel) ; 19(17)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31480570

RESUMO

Human inhibitory control refers to the suppression of behavioral response in real environments, such as when driving a car or riding a motorcycle, playing a game and operating a machine. The P300 wave is a neural marker of human inhibitory control, and it can be used to recognize the symptoms of attention deficit hyperactivity disorder (ADHD) in human. In addition, the P300 neural marker can be considered as a stop command in the brain-computer interface (BCI) technologies. Therefore, the present study of electroencephalography (EEG) recognizes the mindset of human inhibition by observing the brain dynamics, like P300 wave in the frontal lobe, supplementary motor area, and in the right temporoparietal junction of the brain, all of them have been associated with response inhibition. Our work developed a hierarchical classification model to identify the neural activities of human inhibition. To accomplish this goal phase-locking value (PLV) method was used to select coupled brain regions related to inhibition because this method has demonstrated the best performance of the classification system. The PLVs were used with pattern recognition algorithms to classify a successful-stop versus a failed-stop in left-and right-hand inhibitions. The results demonstrate that quadratic discriminant analysis (QDA) yielded an average classification accuracy of 94.44%. These findings implicate the neural activities of human inhibition can be utilized as a stop command in BCI technologies, as well as to identify the symptoms of ADHD patients in clinical research.


Assuntos
Eletroencefalografia/métodos , Interfaces Cérebro-Computador , Potencial Evocado P300/fisiologia , Potenciais Evocados/fisiologia , Humanos
3.
Med Biol Eng Comput ; 57(9): 2069-2079, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31352660

RESUMO

Divided attention is defined as focusing on different tasks at once, and this is described as one of the biggest problems of today's society. Default examinations for understanding attention are questionnaires or physiological signals, like evoked potentials and electroencephalography. Physiological records were obtained using visual, auditory, and auditory-visual stimuli combinations with 48 participants-18-25-year-old university students-to find differences between sustained and divided attention. A Fourier-based filter was used to get a 0.01-30-Hz frequency band. Fractal dimensions, entropy values, power spectral densities, and Hjorth parameters from electroencephalography and P300 components from evoked potentials were calculated as features. To decrease the size of the feature set, some features, which yield less detail level for data, were eliminated. The visual and auditory stimuli in selective attention were compared with the divided attention state, and the best accuracy was found to be 88.89% on a support vector machine with linear kernel. As a result, it was seen that divided attention could be more difficult to determine from selective attention, but successful classification could be obtained with appropriate methods. Contrary to literature, the study deals with the infrastructure of attention types by working on a completely healthy and attention-high group. Graphical abstract.


Assuntos
Atenção/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Processamento de Sinais Assistido por Computador , Estimulação Acústica , Adolescente , Adulto , Entropia , Potencial Evocado P300/fisiologia , Feminino , Fractais , Humanos , Masculino , Experimentação Humana não Terapêutica , Estimulação Luminosa , Reprodutibilidade dos Testes , Adulto Jovem
4.
Exp Brain Res ; 237(9): 2397-2409, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31292697

RESUMO

In the present study event-related potentials were used to shed further light on the neural signatures of active inhibition of the (affective) content of written words. Intentional inhibition was implemented by simply asking participants (N = 32) to ignore single words that served as primes in an affective priming (AP) task. In AP, evaluations about a priori neutral targets typically tend to shift towards the valence of preceding primes, denoting an AP effect (APE). To create a plausible cover-context emphasizing the usefulness of word inhibition, participants were asked to avoid this shift, that is, to make unbiased target evaluations. Ignoring the prime words was suggested as the most efficient strategy to achieve this aim. Effective inhibition of the words' (affective) content, as suggested by a significant APE present for words processed without any further instruction, but not for ignored ones, affected multiple stages of processing. On the neuronal level, word inhibition was characterized by reduced early perceptual (left-lateralized word-specific N170), later attentional (parietal P300), and affective-semantic processing (reduced posterior semantic asymmetry). Furthermore, an additional recruitment of top-down inhibitory control processes, which was mirrored in increased amplitudes of medial-frontal negativity, showed to be critically involved in intentional word inhibition.


Assuntos
Afeto/fisiologia , Atenção/fisiologia , Córtex Cerebral/fisiologia , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Adulto , Potencial Evocado P300/fisiologia , Feminino , Humanos , Masculino , Psicolinguística , Semântica , Adulto Jovem
5.
Biol Psychol ; 146: 107726, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31276755

RESUMO

Mental workload has been shown to correlate with alpha and theta band power but only few EEG studies focused on the relation between these bands and Event Related Potentials (ERPs), more specifically the P300 component. We report on an EEG study on mental workload where not only young but also older adults performed an N-Back task. Participants watched a sequence of visual pictures and indicated whether the current picture was the same as the one shown N pictures before. We considered N = 4 difficulty levels and analyzed the relation between these and P300 amplitude and theta and alpha band power, and also examined the effect of age, level of education, work activities, and task accuracy. Our results revealed a decrease in P300 amplitude and alpha band activity for higher difficulty levels for young adults in the parietal region. However, for older adults, fatigue played a more important role than we could anticipate as the alpha band power increased for the highest task difficulty level, and since performance accuracy also decreased, it could even be a sign of task disengagement. Beside alpha band, theta band activity showed a positive correlation with task difficulty level for both young and older adults. Additionally, we found higher P300 amplitudes for young adults compared to older adults, in line with their higher performance accuracies and lower reaction times. In conclusion, we showed that P300 amplitude and alpha and theta bands power provide complementary information for judging mental workload during N-Back performance for young and older subjects and for detecting mental fatigue and task disengagement.


Assuntos
Envelhecimento/psicologia , Potenciais Evocados/fisiologia , Carga de Trabalho , Adulto , Ritmo alfa/fisiologia , Escolaridade , Eletroencefalografia , Potencial Evocado P300/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lobo Parietal/fisiologia , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Ritmo Teta/fisiologia , Adulto Jovem
6.
Dev Cogn Neurosci ; 38: 100677, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31255904

RESUMO

While it is well established that lower socioeconomic status (SES) is associated with poorer executive functioning (EF), how SES relates to the neural processing of EF in childhood remains largely unexplored. We examined how household income and parent education related to amplitudes of the P3b, an event-related potential component, during one EF task. We assessed the P3b, indexing inhibition and attention allocation processes, given the importance of these skills for academic success. Children aged 4.5-5.5 years completed a go/no-task, which assesses inhibitory control and attention, while recording EEG. The P3b was assessed for both go trials (indexing sustained attention) and no-go trials (indexing inhibition processes). Higher household income was related to larger P3b amplitudes on both go and no-go trials. This was a highly educated sample, thus results indicate that P3b amplitudes are sensitive to household income even within the context of high parental education. Findings build on the behavioral literature and demonstrate that SES also has implications for the neural mechanisms underlying inhibition and attention processing in early childhood.


Assuntos
Potencial Evocado P300/fisiologia , Função Executiva/fisiologia , Desempenho Psicomotor/fisiologia , Classe Social , Adulto , Atenção/fisiologia , Pré-Escolar , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Adulto Jovem
7.
Acta Neurobiol Exp (Wars) ; 79(1): 25-38, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31038483

RESUMO

Here, we evaluated the P3b potential evoked in a visual two-stimulus oddball paradigm. The experiment was conducted in 20 healthy students (23.1±1.1 years, 10 women), using a 32 channel electroencephalography (EEG) montage system. The paradigm included geometric figures; a black square on a white background as a target and a white circle on a black background as a standard stimulus. We examined the maximal amplitude and latency of the P3b component at 18 electrode sites, as well as, temporal changes of scalp voltage distribution. We observed a non-equal spatial distribution of the visual ERP (event related potentials) waveforms on the scalp surface, with the highest P3b waveform observed over midline parietal areas and the lowest over frontal regions. Moreover, the spatial distribution of ERP signal on the scalp surface was more lateralized towards the right side in men and more centralized in women. Gender-related differences in P3b amplitude and latency were observed only in left hemisphere. Differences in P3b between men and women observed in our study arose not only from different P3b amplitudes and latencies, but also from the speed and character of P3b waveform fall, resulting in spatio-temporal amplitude changes. Moreover, the spatial distribution of the P200 potential also changed on the scalp differently in men and women. These results suggest that gender-related differences evoked in visual two-stimulus oddball paradigm, which engage attention processes, are complex and include spatio-temporal changes in P3b waveform generation, distribution, and suppression across the scalp.


Assuntos
Mapeamento Encefálico , Potencial Evocado P300/fisiologia , Caracteres Sexuais , Adulto , Eletroencefalografia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Análise de Regressão , Estatísticas não Paramétricas , Adulto Jovem
8.
Brain Cogn ; 132: 89-97, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30939357

RESUMO

Sleep loss has a major effect on cognitive tasks that are dependent on the maintenance of active sustained attention. This study examines the effects of sleep deprivation on automatic information processing, more specifically, its effect on processes leading to involuntary auditory attention capture by task-irrelevant auditory events. Two experiments were run. In the first, 13 participants were totally sleep-deprived (TSD); in the second, 16 participants were partially sleep-deprived (PSD), sleeping only four hours. Event-related potentials were recorded while participants discriminated the duration of equiprobable short and long auditory tones. At rare times, a small change to the pitch of these stimuli occurred. This deviant was however irrelevant to the duration detection task. As expected, TSD had a significant effect on the attention-dependent duration detection task; performance was worse and the P3b, associated with ease of detection, was attenuated. PSD had a similar, but reduced effect. Critically, the small pitch deviant resulted in less behavioural distraction following TSD compared to normal sleep.Consistent with this, the P3a, associated with the attention capture process, was significantly reduced following both TSD and PSD. Processes related to the passive switching of attention to potentially critical, but unattended, stimulus events are moderated by sleep deprivation.


Assuntos
Atenção/fisiologia , Potencial Evocado P300/fisiologia , Potenciais Evocados Auditivos/fisiologia , Privação do Sono/fisiopatologia , Estimulação Acústica/métodos , Adulto , Percepção Auditiva , Eletroencefalografia/métodos , Potenciais Evocados , Feminino , Humanos , Masculino , Sono , Adulto Jovem
9.
Actas esp. psiquiatr ; 47(2): 54-60, mar.-abr. 2019. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-181340

RESUMO

Introducción. El trastorno por déficit de atención (TDA) ha sido estudiado desde muchos puntos de vista, sin embargo, todavía se desconocen los mecanismos neurobiológicos subyacentes al mismo. Los potenciales evocados y entre ellos el componente P300 pueden servir para investigar los procesos de las funciones cognitivas y atencionales deficitarios en los niños con TDA. Metodología. En este estudio analizamos la eficacia del programa del neuroeducativo HERVAT (acrónimo de Hidratación, Equilibrio, Respiración. Visión, Audición, Tacto) en el potencial evocado P300 en un grupo de niños, entre 7 y 11 años con TDA. Resultados. Los resultados indican que al final del estudio los niños con TDA que han hecho el programa HERVAT han mejorado la latencia del P300 y han reorganizado la actividad cerebral hacia áreas frontales mientras que el grupo control mantiene la misma latencia del P300 y las mismas áreas corticales posteriores durante la tarea de discriminación de estímulos multisensoriales. Conclusiones. Como conclusión podríamos decir que el programa neuroeducativo HERVAT manifiesta su eficacia en el acortamiento de la latencia del potencial evocado P300, responsable del procesamiento cerebral de la información, así como en la reorganización de la actividad cerebral desde áreas posteriores cerebrales hacia áreas corticales frontales, responsables de los procesos atencionales de las funciones ejecutivas


Introduction. Attention deficit disorder (ADD) has been investigated from various perspectives. However, the neurobiological mechanisms underlying this condition remain unknown. Evoked potentials, including P300, can be used to investigate the processes underlying deficient attentional and cognitive functions in children with ADD. Methods. In this study, we analyze the effect of a neuroeducational program, HERVAT (Hidratacion [hydration], Equilibrio [balance], Respiracion [breathing], Vision [vision], Audicion [hearing], Tacto [touch]), on evoked potential P300 in a group of children aged 7-11 years with ADD. Results. At the end of the study, the latency of P300 improved and brain activity was reorganized toward frontal areas in children with ADD who undertook the HERVAT program. In the control group, on the other hand, the latency of P300 and the posterior cortical areas remained unchanged during tests to discriminate between multisensory stimuli. Conclusions. In conclusion, the neuroeducational program HERVAT effectively shortened the latency of evoked potential P300, which is responsible for information processing in the brain, and reorganized brain activity from posterior areas toward frontal cortical areas, which are responsible for the attentional processes involved in executive function


Assuntos
Humanos , Masculino , Feminino , Criança , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Potencial Evocado P300/fisiologia , Cognição/fisiologia , Neurobiologia/instrumentação , Ensino Fundamental e Médio , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Eletroencefalografia/métodos
10.
Epilepsy Res ; 153: 71-75, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30824370

RESUMO

Neuromodulation therapies represent an important treatment arm for patients with drug-resistant epilepsy (DRE) who are not candidates for resective surgery. Vagus nerve stimulation (VNS) - the neurostimulation modality in focus in this review - was the first available neuromodulatory therapy for DRE and was followed by anterior thalamic deep brain stimulation (ANT-DBS) and responsive neurostimulation (RNS). Although no comparative trials of these treatments have been performed, published data and clinical experience suggest comparable effectiveness. In VNS, DBS and RNS seizure reduction is delayed and increases over time raising the question of anti-epileptogenic mechanisms of neuromodulation. Considering the long-term effectiveness assumed for neuromodulatory treatments and the chronic nature of drug-resistant epilepsy, study designs allowing for long-term comparative observations would be of great value, but are hindered by the inherent nature of a long-term [surgical] control group and the bias associated with open-label trials. New trial designs using objective endpoints are needed, and may be aided by novel biomarkers of risk and disease severity for specific epilepsy populations.


Assuntos
Encéfalo/fisiologia , Epilepsia/terapia , Estimulação do Nervo Vago/métodos , Animais , Estimulação Encefálica Profunda , Eletroencefalografia , Potencial Evocado P300/fisiologia , História do Século XX , História do Século XXI , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estimulação do Nervo Vago/história
11.
Int J Neural Syst ; 29(6): 1950002, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30880525

RESUMO

Event-related potentials (ERPs) especially P300 are popular effective features for brain-computer interface (BCI) systems based on electroencephalography (EEG). Traditional ERP-based BCI systems may perform poorly for small training samples, i.e. the undersampling problem. In this study, the ERP classification problem was investigated, in particular, the ERP classification in the high-dimensional setting with the number of features larger than the number of samples was studied. A flexible group sparse discriminative analysis algorithm based on Moreau-Yosida regularization was proposed for alleviating the undersampling problem. An optimization problem with the group sparse criterion was presented, and the optimal solution was proposed by using the regularized optimal scoring method. During the alternating iteration procedure, the feature selection and classification were performed simultaneously. Two P300-based BCI datasets were used to evaluate our proposed new method and compare it with existing standard methods. The experimental results indicated that the features extracted via our proposed method are efficient and provide an overall better P300 classification accuracy compared with several state-of-the-art methods.


Assuntos
Interfaces Cérebro-Computador , Análise Discriminante , Eletroencefalografia/métodos , Potencial Evocado P300/fisiologia , Algoritmos , Humanos
12.
Neuroimage Clin ; 22: 101760, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30927608

RESUMO

BACKGROUND: Mismatch negativity (MMN) is a measure of pre-attentive auditory information processing related to change detection. Traditional scalp-level EEG methods consistently find attenuated MMN in patients with chronic but not first-episode schizophrenia. In the current paper, we use a source-resolved method to assess MMN and hypothesize that more subtle changes can be identified with this analysis method. METHOD: Fifty-six first-episode antipsychotic-naïve schizophrenia (FEANS) patients (31 males, 25 females, mean age 24.6) and 64 matched controls (37 males, 27 females, mean age 24.8) were assessed for duration-, frequency- and combined-type MMN and P3a as well as 4 clinical, 3 cognitive and 3 psychopathological measures. To evaluate and correlate MMN at source-level, independent component analysis (ICA) was applied to the continuous EEG data to derive equivalent current dipoles which were clustered into 19 clusters based on cortical location. RESULTS: No scalp channel group MMN or P3a amplitude differences were found. Of the localized clusters, several were in or near brain areas previously suggested to be involved in the MMN response, including frontal and anterior cingulate cortices and superior temporal and inferior frontal gyri. For duration deviants, MMN was attenuated at the right superior temporal gyrus in patients compared to healthy controls (p = 0.01), as was P3a at the superior frontal cortex (p = 0.01). No individual patient correlations with clinical, cognitive, or psychopathological measures survived correction for multiple comparisons. CONCLUSION: Attenuated source-localized MMN and P3a peak contributions can be identified in FEANS patients using a method based on independent component analysis (ICA). This indicates that deficits in pre-attentive auditory information processing are present at this early stage of schizophrenia and are not the result of disease chronicity or medication. This is to our knowledge the first study on FEANS patients using this more detailed method.


Assuntos
Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Esquizofrenia/fisiopatologia , Processamento de Sinais Assistido por Computador , Adulto , Potencial Evocado P300/fisiologia , Potenciais Evocados Auditivos/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
13.
PLoS One ; 14(2): e0212483, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30818382

RESUMO

Along with improvement in electroencephalogram (EEG)-measurement technology, limitations on the situations in which data can be recorded are gradually being overcome. EEG measurement in real environments has become increasingly important as a means to monitor brain activity in our daily lives, such as while playing consumer games in the living room. The present study measured brain EEG activity while two players engaged in a competitive consumer baseball game in conditions that closely resembled daily life. The recorded brain activity was thus likely related to natural mental reactions and cognitive function that occur in similar daily life activities. To measure the EEG from participants who freely moved while playing the game, we developed EEG devices that incorporated a wireless time synchronization system using Global Positioning Satellite (GPS) signals. These devices stamped the time obtained from the GPS signals onto each data sample, which was then used to synchronize the data that were recorded by different devices. When the batter in the game swung and missed, the error-related negativity component of the event-related EEG potential was strongly evoked in frontal electrodes of the participant controlling the batter. Furthermore, the error-related negativity was modulated according to who was winning and by how much. Thus, here we have demonstrated "real-world" brain activity using a competitive consumer game, which increases intrinsic participant motivation.


Assuntos
Jogos de Vídeo/psicologia , Adulto , Beisebol , Encéfalo/fisiologia , Comportamento Competitivo/fisiologia , Eletroencefalografia/estatística & dados numéricos , Potencial Evocado P300/fisiologia , Potenciais Evocados/fisiologia , Feminino , Sistemas de Informação Geográfica , Humanos , Masculino , Tecnologia sem Fio , Adulto Jovem
14.
J Nerv Ment Dis ; 207(3): 209-216, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30747792

RESUMO

Evidence from a neuropsychological test revealed that interictal epileptiform discharges (IEDs) may have significant impact on cognitive performance. Sometimes, neuropsychological tests may not be sensitive to detection of mild cognitive changes. We applied P300 and mismatch negativity (MMN) to detect mild cognitive changes caused by small amount of IEDs. Sixty-seven adult epilepsy patients and participants were divided into six groups according to different IEDs index. The patients with IED index greater than 7.5% showed longer latency and lower amplitude in the test of P300 and MMN than patients with IED index less than 7.5%, which indicated mild impaired cognitive function. The negative effect of IED index greater than 10% on cognitive has been found by neuropsychological test, whereas the mild negative effect of IED index greater than 7.5% has only been found by P300 and MMN. So, P300 and MMN may be more sensitive than neuropsychological tests to detect mild cognitive impairment caused by IEDs.


Assuntos
Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/fisiopatologia , Epilepsia/fisiopatologia , Potenciais Evocados/fisiologia , Adolescente , Adulto , Disfunção Cognitiva/etiologia , Eletroencefalografia , Epilepsia/complicações , Potencial Evocado P300/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Adulto Jovem
15.
Prog Brain Res ; 244: 101-114, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30732833

RESUMO

In the study of the electrophysiological correlates of attention, a phasic change in alertness has been classically related to a negative frontal-central shift called Contingent Negative Variation (CNV). Studies investigating the effects of meditation on the CNV in participants reporting frequent transcendental experiences (TE) reported reduced CNV in choice reaction time task (CRT), and increased CNV in simple reaction time task (SRT), suggesting that meditation can induce a more balanced attentional state. In the current study, we tested whether a similar effect could be obtained in healthy non-meditators using a single session of a specifically structured sensorimotor training (Quadrato Motor Training-QMT). In addition, in contrast to previous studies, we further examined the P3 component, reflecting cognitive load and novelty detection. We found that similar to previous studies, following a QMT session, CNV amplitude reduced in CRT and increased in SRT. Conversely, the P3 amplitude increased in CRT and decreased in SRT. Taken together, these results support the idea that QMT has attentional benefits in normal healthy participants, similar to those observed in experienced meditators.


Assuntos
Encéfalo/fisiologia , Variação Contingente Negativa/fisiologia , Potencial Evocado P300/fisiologia , Atenção Plena/métodos , Movimento/fisiologia , Adulto , Análise de Variância , Comportamento de Escolha/fisiologia , Eletroencefalografia , Feminino , Humanos , Masculino , Tempo de Reação/fisiologia , Fatores de Tempo , Adulto Jovem
16.
Prog Brain Res ; 244: 115-136, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30732834

RESUMO

Several studies have demonstrated that meditation naïve subjects can, in just a few weeks, become proficient enough in meditation to show cognitive improvements accompanied with functional and structural changes in the brain. Would long-term exposure to qualitatively different levels of meditative training bring about differences in cognitive processing? Would meditation prior to task performance help separate out these differences? Could the nature of the task influence the findings related to cognitive enhancements? To address these questions, we evaluated cognitive functions in three groups of experienced Vipassana practitioners (Novices: n=22, Mean±SD meditation experience=989±595h; Senior practitioners: 21, 10,510±5313; Teachers: 16, 14,648±9623) who differed in terms of duration and quality of meditative practice. Specifically, we employed "ANGEL" a gamified multilevel oddball paradigm, to assess P3 event-related potentials (ERPs) and associated EEG dynamics-power spectra, event related spectral perturbations (ERSP) and inter-trial coherence (ITC). In order to elicit the state-trait influences of meditation, the cognitive task was performed after the participants had undergone an hour long traditional meditation session. All participants could perform the task well and the gross ERP waveforms were similar for the three groups. As hypothesized, we found distinct state-trait influences of meditation leading to graded differences in P3 EEG dynamics. Specifically, we found reduced theta synchrony, enhanced alpha de-synchrony and lesser theta-alpha coherence in the more proficient meditators. Post hoc analyses revealed several differences between the novice and teacher groups but not as many between novice and seniors suggesting that the senior meditators formed an intermediate group. Our study demonstrates that both quantity and quality of meditation influence EEG dynamics during cognitive processing and that meditation prior to a task can provide additional state-trait effects involved in meeting the specific cognitive demands.


Assuntos
Encéfalo/fisiologia , Cognição/fisiologia , Potencial Evocado P300/fisiologia , Meditação/psicologia , Adulto , Idoso , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Espectral
17.
Neurobiol Aging ; 77: 20-25, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30772737

RESUMO

A deviant-related negativity (DRN), mismatch negativity (MMN), and P3a are electrophysiological measures thought to reflect processes involved in the involuntary switching of attention to a task-irrelevant stimulus. The purpose of this article was to determine whether healthy older adults involuntarily detect unattended auditory stimuli as efficiently as younger adults. To test this, 20 younger adults (aged 18-30 years) and 20 older adults (aged 65+ years) were presented with to-be-ignored auditory sequences consisting of frequently presented 80 dB SPL standards and rarely presented increments (+10 dB) and decrements (-20 dB). The MMN to the decrement did not differ between the 2 groups. On the other hand, the DRN to the increment was significantly reduced in the older adults. Importantly, the P3a was also significantly reduced in the older adults. This reduced P3a may reflect a deficit in the involuntary shift of attention from current cognitive demands to a potentially more critical event.


Assuntos
Atenção/fisiologia , Potencial Evocado P300/fisiologia , Potenciais Evocados Auditivos/fisiologia , Envelhecimento Saudável/fisiologia , Audição/fisiologia , Estimulação Acústica , Adolescente , Adulto , Idoso , Cognição/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
18.
Brain Cogn ; 132: 22-32, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30802731

RESUMO

Inhibitory control deficits represent a key aspect of the cognitive declines associated with aging. Practicing inhibitory control has thus been advanced as a potential approach to compensate for age-induced neurocognitive impairments. Yet, the functional brain changes associated with practicing inhibitory control tasks in older adults and whether they differ from those observed in young populations remains unresolved. We compared electrical neuroimaging analyses of ERPs recorded during a Go/NoGo practice session with a Group (Young; Older adults) by Session (Beginning; End of the practice) design to identify whether the practice of an inhibition task in older adults reinforces already implemented compensatory activity or reduce it by enhancing the functioning of the brain networks primarily involved in the tasks. We observed an equivalent small effect of practice on performance in the two age-groups. The topographic ERP analyses and source estimations revealed qualitatively different effects of the practice over the N2 and P3 ERP components, respectively driven by a decrease in supplementary motor area activity and an increase in left ventrolateral prefrontal activity in the older but not in the young adults with practice. Our results thus indicate that inhibition task practice in older adults increases age-related divergences in the underlying functional processes.


Assuntos
Envelhecimento/fisiologia , Potencial Evocado P300/fisiologia , Córtex Motor/fisiologia , Córtex Pré-Frontal/fisiologia , Adulto , Idoso , Encéfalo/fisiologia , Córtex Cerebral/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem , Plasticidade Neuronal , Tempo de Reação/fisiologia , Adulto Jovem
19.
IEEE Trans Neural Syst Rehabil Eng ; 27(3): 533-542, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30716043

RESUMO

This paper presents a new brain-robot interaction system by fusing human and machine intelligence to improve the real-time control performance. This system consists of a hybrid P300 and steady-state visual evoked potential (SSVEP) mode conveying a human being's intention, and the machine intelligence combining a fuzzy-logic-based image processing algorithm with multi-sensor fusion technology. A subject selects an object of interest via P300, and the classification algorithm transfers the corresponding parameters to an improved fuzzy color extractor for object extraction. A central vision tracking strategy automatically guides the NAO humanoid robot to the destination selected by the subject intentions represented by brainwaves. During this process, human supervises the system at high level, while machine intelligence assists the robot in accomplishing tasks by analyzing image feeding back from the camera, distance monitoring using out-of-gauge alarms from sonars, and collision detecting from bumper sensors. In this scenario, the SSVEP takes over the situations in which the machine intelligence cannot make decisions. The experimental results show that the subjects can control the robot to a destination of interest, with fewer commands than only using a brain-robot interface. Therefore, the fusion of human and machine intelligence greatly alleviates the brain load and enhances the robot executive efficiency of a brain-robot interaction system.


Assuntos
Inteligência Artificial , Interfaces Cérebro-Computador , Inteligência , Robótica/métodos , Algoritmos , Eletroencefalografia , Potencial Evocado P300/fisiologia , Potenciais Somatossensoriais Evocados/fisiologia , Lógica Fuzzy , Humanos , Processamento de Imagem Assistida por Computador , Visão Ocular/fisiologia
20.
Neuropsychopharmacology ; 44(6): 1062-1067, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30797222

RESUMO

Schizophrenia is a complex brain disease involving several neurotransmitter systems, including aberrant noradrenergic activity, which might underlie cognitive deficits. Clonidine is an α2A-agonist and previous research has demonstrated that single dosages of clonidine normalize sensori(motor) gating in schizophrenia. Currently, we investigated whether clonidine is able to normalize mismatch negativity (MMN) and P3a amplitude deficits in this same group of patients. This is important, since reports have shown that MMN amplitude is associated with cognitive functioning and daily life functions in schizophrenia. Twenty chronically ill, male schizophrenia patients were tested with the MMN paradigm from the Copenhagen Psychophysiological Test Battery (CPTB) on 5 occasions, separated by a week. Patients received randomized, yet balanced, either a placebo or a single dose (25, 50, 75 or 150 µg) of clonidine (each dose only once) on top of their usual medication on each occasion. Patients were matched on age and gender with 20 healthy controls (HC) who did not receive any treatment. We found decreased MMN and P3a amplitudes in our patients compared to HC. Although clonidine did neither significantly increase MMN nor P3a amplitude in our patients, it did increase certain levels of MMN and P3a amplitude such that these were not significantly different anymore from the healthy controls. Together with our previous reports indicating normalized sensori(motor) gating in the same patients following administration of clonidine, our results could be of potential high clinical relevance in treating schizophrenia. Future studies should focus on longer trial periods to investigate if clonidine also improves cognitive functioning in schizophrenia.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Percepção Auditiva/fisiologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiopatologia , Clonidina/farmacologia , Potenciais Evocados/efeitos dos fármacos , Potenciais Evocados/fisiologia , Esquizofrenia/fisiopatologia , Agonistas de Receptores Adrenérgicos alfa 2/administração & dosagem , Adulto , Antipsicóticos/uso terapêutico , Clonidina/administração & dosagem , Eletroencefalografia , Potencial Evocado P300/efeitos dos fármacos , Potencial Evocado P300/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/tratamento farmacológico
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