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1.
Adv Exp Med Biol ; 1101: 41-65, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31729671

RESUMO

Brain-computer interfaces (BCIs) provide a direct communication channel between human brain and output devices. Due to advantages such as non-invasiveness, ease of use, and low cost, electroencephalography (EEG) is the most popular method for current BCIs. This chapter gives an overview of the current EEG-based BCIs for the main purpose of communication and control. This chapter first provides a taxonomy of the EEG-based BCI systems by categorizing them into three major groups: (1) BCIs based on event-related potentials (ERPs), (2) BCIs based on sensorimotor rhythms, and (3) hybrid BCIs. Next, this chapter describes challenges and potential solutions in developing practical BCI systems toward high communication speed, convenient system use, and low user variation. Then this chapter briefly reviews both medical and non-medical applications of current BCIs. Finally, this chapter concludes with a summary of current stage and future perspectives of the EEG-based BCI technology.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Comunicação , Potenciais Evocados , Humanos
2.
Braz J Otorhinolaryngol ; 85(6): 788-798, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31606334

RESUMO

INTRODUCTION: People with vestibular loss present a deficit in the vestibular system, which is primarily responsible for promoting postural control, gaze stabilization, and spatial orientation while the head moves. There is no effective treatment for a bilateral loss of vestibular function. Recently, a vestibular implant was developed for people with bilateral loss of vestibular function to improve this function and, consequently, the quality of life of these patients. OBJECTIVE: To identify in the scientific literature evidence that vestibular implants in people with vestibular deficit improves vestibular function. METHODS: One hundred and forty six articles were found from five databases and 323 articles from the gray literature mentioning the relationship between vestibular implant and vestibular function in humans. The PICOS strategy (Population, Intervention, Comparison and Outcome) was used to define the eligibility criteria. The studies that met the inclusion criteria for this second step were included in a qualitative synthesis, and each type of study was analyzed according to the bias risk assessment of the Joanna Briggs Institute through the critical assessment checklist Joanna Briggs institute for quasi-experimental studies and the Joanna Briggs institute critical assessment checklist for case reports. RESULTS: Of the 21 articles included in reading the full text, 10 studies were selected for the qualitative analysis in the present systematic review. All ten articles analyzed through the critical assessment checklist Joanna Briggs institute showed a low risk of bias. The total number of samples in the evaluated articles was 18 patients with vestibular implants. CONCLUSIONS: Taken together, these findings support the feasibility of vestibular implant for restoration of the vestibulo-ocular reflex in a broad frequency range and illustrate new challenges for the development of this technology.


Assuntos
Implante Coclear , Doenças Vestibulares/cirurgia , Vestíbulo do Labirinto/fisiologia , Adulto , Distribuição por Idade , Idoso , Potenciais Evocados , Feminino , Humanos , Masculino , Doença de Meniere/fisiopatologia , Pessoa de Meia-Idade , Qualidade de Vida , Distribuição por Sexo , Doenças Vestibulares/fisiopatologia , Testes de Função Vestibular
3.
Spine (Phila Pa 1976) ; 44(21): 1492-1498, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31609917

RESUMO

STUDY DESIGN: A prospective, within-subject study was conducted. OBJECTIVE: We aimed to compare the influence of anesthetic fade under maximum stimulation conditions between constant-current and constant-voltage stimulation techniques. SUMMARY OF BACKGROUND DATA: The monitoring of muscle-evoked potentials after electrical stimulation to the brain [Br(E)-MSEP)] is useful for assessing the integrity of spinal cord motor tracts during major spine surgery. Nonetheless, Br(E)-MSEP responses are known to deteriorate over the duration of surgeries performed under general anesthesia. This phenomenon is known as anesthetic fade. METHODS: We recruited 117 patients undergoing various spinal surgeries from the cervical to the lumbar level. We excluded 29 cases with insufficient data. The decrease rate of the Br(E)-MSEP amplitude for each muscle was examined. Br(E)-MSEP monitoring with constant-current and constant-voltage stimulations at the C3 and C4 electrode positions was applied. Compound muscle action potentials (CMAPs) were bilaterally recorded from the abductor pollicis brevis, deltoid, abductor hallucis, tibialis anterior, gastrocnemius, and quadriceps muscles. We defined the decrease rate as follows: (initial CMAPs-final CMAPs)/initial CMAPs × 100. Differences in the decrease rate were evaluated between stimulators, limbs (upper vs. lower), and operative time group (lowest quartile vs. highest quartile). RESULTS: The overall decrease rate (across all muscles) increased as the operative time increased, and the rate was higher in the lower limbs than in the upper limbs. In addition, the overall decrease rate was lower with constant-voltage stimulation than with constant-current stimulation. Furthermore, the decrease rate for constant-current stimulation was significantly higher than that for constant-voltage stimulation, regardless of the operative time. CONCLUSION: The CMAP waveform with constant-voltage stimulation is less susceptible to anesthetic fade than that with constant-current stimulation, even during long surgeries. LEVEL OF EVIDENCE: 3.


Assuntos
Anestésicos/farmacologia , Encéfalo/efeitos dos fármacos , Potencial Evocado Motor/fisiologia , Músculo Esquelético/fisiologia , Procedimentos Neurocirúrgicos/métodos , Coluna Vertebral/cirurgia , Adulto , Anestesia Geral , Estimulação Elétrica , Eletrodos , Potenciais Evocados , Feminino , Humanos , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
5.
J Autism Dev Disord ; 49(12): 5009-5022, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31486998

RESUMO

Despite evidence suggesting differences in early event-related potential (ERP) responses to social emotional stimuli, little is known about later stage ERP contributions to social emotional processing in individuals with autism spectrum disorder (ASD). Adults with and without ASD completed a facial emotion recognition task involving stimuli that varied by emotional intensity while electroencephalograms were recorded. Principal components analysis was used to examine P300 and late positive potential (LPP) modulation by emotional intensity. Results indicated that greater ASD symptomatology evinced heightened P300 to high relative to low intensity faces, then heightened LPP to low relative to high intensity faces. Findings suggest that adults with greater ASD symptomatology may demonstrate a lag in engagement in elaborative processing of low intensity faces.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Potenciais Evocados , Reconhecimento Facial , Adulto , Emoções , Expressão Facial , Feminino , Humanos , Masculino
6.
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
7.
J Abnorm Psychol ; 128(7): 671-677, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31448932

RESUMO

Hyperactive error monitoring is a robust neurocognitive characteristic in obsessive-compulsive disorder (OCD). Yet, relatively little is known about the flexibility and potential moderators of error monitoring in OCD. The current study investigates error monitoring in 30 healthy participants and 28 patients with OCD using a flanker task in 2 conditions either emphasizing speed or accuracy. Results indicate that no group difference is observable in error-related negativity (ERN) under the accuracy-focused condition. Both groups show an ERN attenuation in the speed condition; however, this reduction is larger in healthy controls leading to pronounced group differences in the speed-focused condition. Similarly, receiver operating characteristic analyses yield an area under the curve (AUC) of .62 in the accuracy-focused condition, whereas under speed instruction an AUC of .85 suggests a marked increase in classification accuracy. Behavioral results and results from a drift-diffusion model of decision making indicate a more cautious response strategy and less adaptability to experimental manipulations in OCD. Overall, results suggest that the observed increases in error-related neural activity in OCD might stem from a reduced flexibility and diminished ability to disengage from an accuracy-oriented, error-avoidant response style. Further, the present results suggest that emphasizing speed in experimental instructions may lead to a better neural differentiation between patients with OCD and healthy controls which has important implications for the use of the ERN as a risk indicator. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Encéfalo/fisiologia , Tomada de Decisões/fisiologia , Potenciais Evocados/fisiologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Transtorno Obsessivo-Compulsivo/psicologia , Adulto Jovem
8.
Brain Cogn ; 135: 103585, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31374347

RESUMO

Breath-focused mindfulness (BFM), which induces changes in brain structure and function, is applied in the clinical treatment of mental disorders as a method to regulate one's emotions. However, whether BFM works through a top-down emotional regulation strategy to alter brain dynamics and its relationship with individual differences in trait mindfulness are unclear. Event-related potentials (ERPs) of 20 healthy BFM-naïve undergraduates were recorded when they conducted BFM/viewing tasks while viewing affective pictures. Participants completed the Attentional Control Scale (ACS) and the Mindful Attention Awareness Scale (MAAS). The results indicated that under the viewing condition, positive and negative pictures elicited greater P1, N2, and late positive potential (LPP) amplitudes than did neutral pictures. However, BFM attenuated P1, N2, and LPP amplitudes for positive and negative pictures but not for neutral pictures. P1 amplitudes for emotional minus neutral pictures correlated with individual differences in focus attention measured by the ACS, while N2 amplitudes for emotional minus neutral pictures correlated with individual differences in trait mindfulness measured by the MAAS. These observations suggest that, consistent with the dual-process model, BFM is an effective emotion regulation strategy and might activate the dorsal top-down prefrontal system to alter early and late neural dynamics of affective processing.


Assuntos
Conscientização/fisiologia , Potenciais Evocados/fisiologia , Atenção Plena/métodos , Respiração , Adolescente , Atenção/fisiologia , Encéfalo/fisiologia , Eletroencefalografia , Emoções/fisiologia , Feminino , Humanos , Individualidade , Masculino , Estudantes , Adulto Jovem
9.
Biol Psychol ; 146: 107733, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31352031

RESUMO

Although people with high interdependent self-construal (SC) are often assumed to be competent in emotion suppression, direct evidence is missing. We tested whether interdependent SC would predict the ability to down-regulate emotional arousal. Americans of both East Asian and European descent were shown a series of pictures. They were instructed to suppress or attend to their emotions. Their electroencephalogram was recorded and analyzed. The late positive potential (LPP) evoked by unpleasant (vs. neutral) pictures (a marker of emotional arousal) was reduced in the suppress (vs. attend) condition. This effect of emotion suppression was more pronounced for those high in interdependent SC than for those low in it. Curiously, the resulting valence x condition x interdependent SC interaction was robust among those of Asian descent, but not those of European descent. The 4-way interaction involving culture was statistically significant. Our work suggests that the purported link between interdependent SC and emotion suppression may be culture-bound.


Assuntos
Americanos Asiáticos/psicologia , Emoções , Autoimagem , Adolescente , Nível de Alerta , Cultura , Eletrocorticografia , Eletroencefalografia , Grupo com Ancestrais do Continente Europeu , Potenciais Evocados/fisiologia , Feminino , Humanos , Individualidade , Masculino , Estimulação Luminosa , Estados Unidos , Adulto Jovem
10.
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
11.
Brain Dev ; 41(8): 662-670, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31337524

RESUMO

OBJECTIVE: To explore impaired cognition characteristics and abnormal behavior in children with Sleep-Disordered Breathing (SDB) via Event-Related Potentials (ERPs), continuous performance testing (CPT), and the Child Behavior Checklist (CBCL). METHODS: A total of 108 children aged 6-8 years old were recruited, including fifty-four children (28 boys) with SDB and fifty-four normal children (28 boys). CBCL and Chinese version of the OSA-18 questionnaire were administered. Nineteen children with SDB (OSA-18 questionnaire value >60) and Nineteen normal children completed a CPT task. ERP was extracted using the BESA software. RESULTS: No significant differences in the correct number, reaction time, or the number of commission error were noted between the CPT of the two groups (P > 0.05). The ERP Go-P3 amplitudes at F3, Fz and F4 of the SDB group were significantly higher than those of the control group (P < 0.05). The NoGo-N2 amplitudes at F3 and Fz of the SDB group were significantly lower than those of the control group (P < 0.05). The Fz and F4 Go-P3 and FZ NoGo-P3 latency of the SDB group were significantly longer than those of the control group (P < 0.05). However, among boys, the CBCL scores of the SDB group including the subscores, schizo, somatic complaints, compulsion, aggression, and hyperactivity, as well as the total score, were significantly higher than the control group (all P < 0.05). CONCLUSION: Children with SDB demonstrate significant functional deficits in regard to conflict monitoring, attention, and inhibition. The frontal region is the primary area of dysfunction, especially in the left brain region, and inhibition function dysfunction may be a common pathogenesis of SDB and ADHD. Moreover, boys with SDB may exhibit more behavior problems when compared to girls.


Assuntos
Transtornos do Comportamento Infantil/etiologia , Potenciais Evocados/fisiologia , Síndromes da Apneia do Sono/fisiopatologia , Atenção/fisiologia , Criança , Transtornos do Comportamento Infantil/metabolismo , China , Cognição/fisiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Tempo de Reação/fisiologia , Síndromes da Apneia do Sono/metabolismo , Inquéritos e Questionários
12.
Biol Psychol ; 146: 107724, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31323242

RESUMO

In face-to-face conversations, when listeners process and combine information obtained from hearing and seeing a speaker, they mostly look at the eyes rather than at the more informative mouth region. Measuring event-related potentials, we tested whether fixating the speaker's eyes is sufficient for gathering enough visual speech information to modulate early auditory processing, or whether covert attention to the speaker's mouth is needed. Results showed that when listeners fixated the eye region of the speaker, the amplitudes of the auditory evoked N1 and P2 were reduced when listeners heard and saw the speaker than when they only heard her. These cross-modal interactions also occurred when, in addition, attention was restricted to the speaker's eye region. Fixating the speaker's eyes thus provides listeners with sufficient visual information to facilitate early auditory processing. The spread of covert attention to the mouth area is not needed to observe audiovisual interactions.


Assuntos
Percepção Auditiva/fisiologia , Olho , Fixação Ocular/fisiologia , Percepção Social , Eletroencefalografia , Potenciais Evocados/fisiologia , Potenciais Evocados Auditivos/fisiologia , Feminino , Humanos , Masculino , Boca , Estimulação Luminosa , Percepção da Fala , Adulto Jovem
13.
Acta Neurobiol Exp (Wars) ; 79(2): 193-204, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31342955

RESUMO

Humans use temporal regularities in their daily life to act in accordance with future events in the most efficient way. To achieve this, humans build temporal expectations and determine a template action that is in line with those expectations. In this temporal trisection study, we aimed to study the neurophysiological counterparts of temporal expectation and response discrimination. We investigated amplitude variations of early event-related potentials (ERPs) while manipulating time intervals. We measured temporal expectation-related attenuation of neural activity and response discrimination processes in N1 and P2 ERP components. Results showed that the amplitude of the N1 component was attenuated for the predicted task-relevant temporal location of a response decision. The P2 amplitude, in contrast, was enhanced for a discriminated response in comparison to a template response. The present study supports a link between the different functional associations of the N1 and P2 components within the requirements of a timing task. N1-related amplitude modulation can determine a change in expectation level during timing. The amplitude regulation of the P2 component, in contrast, explains temporal discrimination in both expected and unexpected temporal locations. In addition to expectation­related modulation, our results suggest an additional regulation of the N1 amplitude that is linked to attention. The effect was observed in instances that included a prediction error of a task-relevant temporal location for a response decision. In conclusion, our study contributes to the growing neurocognitive literature on interval timing by capturing different aspects of a timing task; namely, N1-related expectation and P2-related response discrimination processes.


Assuntos
Atenção/fisiologia , Potenciais Evocados Auditivos/fisiologia , Potenciais Evocados/fisiologia , Motivação/fisiologia , Estimulação Acústica/métodos , Adulto , Mapeamento Encefálico/métodos , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Tempo de Reação
14.
Brain Cogn ; 135: 103584, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31302576

RESUMO

It is known that the longer an information has been memorized, the stronger is its memory trace, and that emotionally-valenced information is more solid than neutral one. We investigated whether the emotional content of recent information might enhance its memory, making it as familiar as information known for a long time. We compared ERPs alternately recorded in response to old and solid information from long term memory (i.e., faces of popular movie stars), to recently acquired emotional information (faces of fictional characters), and to completely new information (faces of previously unknown people). Initially participants familiarized with the fictional police dossiers of 10 victims of dramatic deaths (recent faces), twice a day for seven days before EEG recordings. Recent faces were compared with faces of movie stars and unknown faces in an old/new recognition task. N200 and FN400 responses were affected by face familiarity (with no difference between old and recent faces), while parietal late positivity (LP) was sensitive to temporal recency, being it greater to old than recent faces. Interestingly, LP amplitude was similar for old and recent own-sex faces (victims) that were therefore equally memorable. It is shown that emotional memory can overcome temporal recency thus improving memory recall.


Assuntos
Encéfalo/fisiologia , Emoções/fisiologia , Potenciais Evocados/fisiologia , Face , Memória de Longo Prazo/fisiologia , /fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
15.
Exp Brain Res ; 237(9): 2423-2430, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31302735

RESUMO

Despite recent increased attention to emotion conflict, little is known about whether emotion-label words (e.g., sadness, happiness) and emotion-laden words (e.g., death, birthday) function similarly in emotion conflict (i.e., a conflict between the target and distractor in emotion involvement), because the majority of the previous studies implicitly mixed the two. The present study aimed to compare emotion-label words and emotion-laden words in emotion conflict using a flanker task. Specifically, participants (N = 21) were asked to judge the valence of the target words that were vertically surrounded by the words with same (congruent) or different (incongruent) valence as being negative or positive. The behavioral results suggested that negative emotion-laden words were processed faster and more accurately than negative emotion-label words. ERP data further showed that negative emotion-label words elicited larger N200 than negative emotion-laden words on the left hemisphere, while such a difference was found for positive words on the right hemisphere. Moreover, emotion-laden words elicited smaller N200 in the incongruent condition than in the congruent condition, whereas no such a distinction was observed for emotion-label words. The findings suggest different cognitive and neural correlates of emotion-label words and emotion-laden words in emotion conflict.


Assuntos
Emoções/fisiologia , Potenciais Evocados/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Leitura , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Psicolinguística , Adulto Jovem
16.
J Abnorm Psychol ; 128(6): 610-621, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31318241

RESUMO

Borderline personality disorder (BPD) is a complex and debilitating psychiatric illness. Prior research in adults has shown that neurophysiological deficits in feedback processing and learning from rewards may be central to the development of BPD; however, little research has examined these markers in adolescents and young adults with BPD. The present study used event-related potentials and time-frequency decomposition analysis to probe neural responses to wins and losses in a guessing task among 68 females (13 to 23 years old) either with BPD (n = 35) or no history of mental disorders (healthy control [HC]; n = 33). Participants completed a guessing task wherein they won and lost money at equal frequencies while electroencephalogram (EEG) data were acquired. Adolescents and young adults with BPD showed a smaller differentiation between wins and losses in the reward positivity (RewP) relative to HCs. Using time-frequency decomposition, we isolated distinct frequency bands sensitive to wins (delta = < 3Hz) and losses (theta = 4 Hz to 7 Hz). Compared with BPD participants, HCs showed significantly larger delta power to wins, specifically. The groups did not differ in delta power to losses, nor theta power to wins or losses. Collectively, findings implicate altered reward processing in the pathophysiology of BPD and may inform early identification and targeted intervention. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Transtorno da Personalidade Borderline/fisiopatologia , Ondas Encefálicas/fisiologia , Potenciais Evocados/fisiologia , Recompensa , Adolescente , Adulto , Transtorno da Personalidade Borderline/psicologia , Feminino , Humanos , Adulto Jovem
17.
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
18.
Biol Psychol ; 146: 107728, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31306692

RESUMO

The perception of surprised faces is demonstrably modulated by emotional context. However, the influence of self-relevance and its interaction with emotional context have not been explored. The present study investigated the effects of contextual valence and self-reference on the perception of surprised faces. Our results revealed that faces in a negative context elicited a larger N170 than those in a neutral context. The EPN was affected by the interaction between contextual valence and self-reference, with larger amplitudes for faces in self-related positive contexts and sender-related negative contexts. Additionally, LPP amplitudes were enhanced for faces in negative contexts relative to neutral and positive contexts, as well as for self-related contexts in comparison to sender-related contexts. Together, these findings help to elucidate the psychophysiological mechanisms underlying the effects of emotional and self-referential contexts on the perception of surprised faces, which are characterized by distinctive ERPs.


Assuntos
Emoções/fisiologia , Potenciais Evocados/fisiologia , Expressão Facial , Autoimagem , Adolescente , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
19.
Handb Clin Neurol ; 160: 543-558, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31277875

RESUMO

Event-related potentials (ERPs) are one of the most commonly used tools to assess cognitive processing with a high temporal resolution. We provide an updated view of the cortical origins of evoked responses and discuss potential mechanisms contributing to ERP generation. In particular, we focus on the relationship between evoked and ongoing oscillatory activity and discuss the differences between ERPs and cortical activation as indexed by high-frequency activity in human intracranial electroencephalography (EEG). We highlight several possibilities for how ERPs can precisely index human perception and behavior in nontraditional approaches, such as neuronal entrainment through steady-state evoked potentials, multivariate decoding, and cross-frequency correlations. We argue that analyses of time-locked responses are beneficial to assess nonlinear and nonsinusoidal neuronal activity on a fine-grained temporal scale, since analyses in the time domain are less susceptible to artifacts than spectral decomposition techniques. Taken together, the current review provides a state-of-the-art overview of ERPs and their application in cognitive and clinical neurophysiology.


Assuntos
Encéfalo/fisiologia , Cognição/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Encéfalo/fisiopatologia , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/fisiopatologia , Transtornos Mentais/psicologia
20.
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
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