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1.
Sensors (Basel) ; 21(17)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34502877

RESUMO

With the prevalence of virtual avatars and the recent emergence of metaverse technology, there has been an increase in users who express their identity through an avatar. The research community focused on improving the realistic expressions and non-verbal communication channels of virtual characters to create a more customized experience. However, there is a lack in the understanding of how avatars can embody a user's signature expressions (i.e., user's habitual facial expressions and facial appearance) that would provide an individualized experience. Our study focused on identifying elements that may affect the user's social perception (similarity, familiarity, attraction, liking, and involvement) of customized virtual avatars engineered considering the user's facial characteristics. We evaluated the participant's subjective appraisal of avatars that embodied the participant's habitual facial expressions or facial appearance. Results indicated that participants felt that the avatar that embodied their habitual expressions was more similar to them than the avatar that did not. Furthermore, participants felt that the avatar that embodied their appearance was more familiar than the avatar that did not. Designers should be mindful about how people perceive individuated virtual avatars in order to accurately represent the user's identity and help users relate to their avatar.


Assuntos
Expressão Facial , Interface Usuário-Computador , Emoções , Humanos , Percepção Social
2.
Sensors (Basel) ; 21(13)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34283146

RESUMO

People tend to display fake expressions to conceal their true feelings. False expressions are observable by facial micromovements that occur for less than a second. Systems designed to recognize facial expressions (e.g., social robots, recognition systems for the blind, monitoring systems for drivers) may better understand the user's intent by identifying the authenticity of the expression. The present study investigated the characteristics of real and fake facial expressions of representative emotions (happiness, contentment, anger, and sadness) in a two-dimensional emotion model. Participants viewed a series of visual stimuli designed to induce real or fake emotions and were signaled to produce a facial expression at a set time. From the participant's expression data, feature variables (i.e., the degree and variance of movement, and vibration level) involving the facial micromovements at the onset of the expression were analyzed. The results indicated significant differences in the feature variables between the real and fake expression conditions. The differences varied according to facial regions as a function of emotions. This study provides appraisal criteria for identifying the authenticity of facial expressions that are applicable to future research and the design of emotion recognition systems.


Assuntos
Emoções , Expressão Facial , Ira , Felicidade , Humanos , Reconhecimento Psicológico
3.
Sensors (Basel) ; 20(11)2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32492974

RESUMO

Empathy can bring different benefits depending on what kind of emotions people empathize with. For example, empathy with negative emotions can raise donations to charity while empathy with positive emotions can increase participation during remote education. However, few studies have focused on the physiological differences depending on what kind of emotions people empathize with. Furthermore, co-viewer can influence the elicitation of different levels of empathy, but this has been less discussed. Therefore, this study investigated vagal response differences according to each empathy factor level elicited by different emotions and co-viewer. Fifty-nine participants were asked to watch 4 videos and to evaluate subjective valence, arousal scores, and undertake an empathy questionnaire, which included cognitive, affective and identification empathy. Half of the participants watched the videos alone and the other half watched the videos with a co-viewer. Valence and arousal scores were categorized into three levels to figure out what kind of emotions they empathized with. Empathy level (high vs. low) was determined based on the self-report scores. Two-way MANOVA revealed an interaction effect of empathy level and emotions. High affective empathy level is associated with higher vagal response regardless of what kind of emotions they empathized with. However, vagal response differences in other empathy factor level showed a different pattern depending on what kind of emotions that participant empathized with. A high cognitive empathy level showed lower vagal responses when participants felt negative or positive valence. High identification level also showed increased cognitive burden when participants empathized with negative and neutral valence. The results implied that emotions and types of empathy should be considered when measuring empathic responses using vagal tone. Two-way MANOVA revealed empathic response differences between co-viewer condition and emotion. Participants with a co-viewer felt higher vagal responses and self-reporting empathy scores only when participants empathized with arousal. This implied that the effect of a co-viewer may impact on empathic responses only when participants felt higher emotional intensity.


Assuntos
Emoções , Empatia , Nervo Vago/fisiologia , Nível de Alerta , Humanos , Autorrelato
4.
Sensors (Basel) ; 20(3)2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31991587

RESUMO

The increasing interest in the effects of emotion on cognitive, social, and neural processes creates a constant need for efficient and reliable techniques for emotion elicitation. Emotions are important in many areas, especially in advertising design and video production. The impact of emotions on the audience plays an important role. This paper analyzes the physical elements in a two-dimensional emotion map by extracting the physical elements of a video (color, light intensity, sound, etc.). We used k-nearest neighbors (K-NN), support vector machine (SVM), and multilayer perceptron (MLP) classifiers in the machine learning method to accurately predict the four dimensions that express emotions, as well as summarize the relationship between the two-dimensional emotion space and physical elements when designing and producing video.


Assuntos
Emoções , Aprendizado de Máquina , Máquina de Vetores de Suporte/legislação & jurisprudência , Gravação de Videodisco , Cor , Humanos , Filmes Cinematográficos , Redes Neurais de Computação
5.
Sensors (Basel) ; 19(23)2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31810275

RESUMO

Embodied emotion is associated with interaction among a person's physiological responses, behavioral patterns, and environmental factors. However, most methods for determining embodied emotion has been considered on only fragmentary independent variables and not their inter-connectivity. This study suggests a method for determining the embodied emotion considering interactions among three factors: the physiological response, behavioral patterns, and an environmental factor based on life-logging. The physiological response was analyzed as heart rate variability (HRV) variables. The behavioral pattern was calculated from features of Global Positioning System (GPS) locations that indicate spatiotemporal property. The environmental factor was analyzed as the ambient noise, which is an external stimulus. These data were mapped with the emotion of that time. The emotion was evaluated on a seven-point scale for arousal level and valence level according to Russell's model of emotion. These data were collected from 79 participants in daily life for two weeks. Their relationships among data were analyzed by the multiple regression analysis, after pre-processing the respective data. As a result, significant differences between the arousal level and valence level of emotion were observed based on their relations. The contributions of this study can be summarized as follows: (1) The emotion was recognized in real-life for a more practical application; (2) distinguishing the interactions that determine the levels of arousal and positive emotion by analyzing relationships of individuals' life-log data. Through this, it was verified that emotion can be changed according to the interaction among the three factors, which was overlooked in previous emotion recognition.


Assuntos
Emoções/fisiologia , Feminino , Sistemas de Informação Geográfica , Humanos , Masculino , Fotopletismografia
6.
Sensors (Basel) ; 19(15)2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31344939

RESUMO

Heart rate has been measured comfortably using a camera without the skin-contact by the development of vision-based measurement. Despite the potential of the vision-based measurement, it has still presented limited ability due to the noise of illumination variance and motion artifacts. Remote ballistocardiography (BCG) was used to estimate heart rate from the ballistocardiographic head movements generated by the flow of blood through the carotid arteries. It was robust to illumination variance but still limited in the motion artifacts such as facial expressions and voluntary head motions. Recent studies on remote BCG focus on the improvement of signal extraction by minimizing the motion artifacts. They simply estimated the heart rate from the cardiac signal using peak detection and fast fourier transform (FFT). However, the heart rate estimation based on peak detection and FFT depend on the robust signal estimation. Thus, if the cardiac signal is contaminated with some noise, the heart rate cannot be estimated accurately. This study aimed to develop a novel method to improve heart rate estimation from ballistocardiographic head movements using the unsupervised clustering. First, the ballistocardiographic head movements were measured from facial video by detecting facial points using the good-feature-to-track (GFTT) algorithm and by tracking using the Kanade-Lucas-Tomasi (KLT) tracker. Second, the cardiac signal was extracted from the ballistocardiographic head movements by bandpass filter and principal component analysis (PCA). The relative power density (RPD) was extracted from its power spectrum between 0.75 Hz and 2.5 Hz. Third, the unsupervised clustering was performed to construct a model to estimate the heart rate from the RPD using the dataset consisting of the RPD and the heart rate measured from electrocardiogram (ECG). Finally, the heart rate was estimated from the RPD using the model. The proposed method was verified by comparing it with previous methods using the peak detection and the FFT. As a result, the proposed method estimated a more accurate heart rate than previous methods in three experiments by levels of the motion artifacts consisting of facial expressions and voluntary head motions. The four main contributions are as follows: (1) the unsupervised clustering improved the heart rate estimation by overcoming the motion artifacts (i.e., facial expressions and voluntary head motions); (2) the proposed method was verified by comparing with the previous methods using the peak detection and the FFT; (3) the proposed method can be combined with existing vision-based measurement and can improve their performance; (4) the proposed method was tested by three experiments considering the realistic environment including the motion artifacts, thus, it increases the possibility of the non-contact measurement in daily life.


Assuntos
Balistocardiografia , Movimentos da Cabeça/fisiologia , Frequência Cardíaca/fisiologia , Movimento/fisiologia , Eletrocardiografia , Humanos , Processamento de Sinais Assistido por Computador
7.
Appl Opt ; 58(13): 3467-3480, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044844

RESUMO

This study was carried out to evaluate a method used to measure three-dimensional (3D) cognitive fatigue based on the pupillary response. This technique was designed to overcome measurement burdens by using non-contact methods. The pupillary response is related to cognitive function by a neural pathway and may be an indicator of 3D cognitive fatigue. Twenty-six undergraduate students (including 14 women) watched both 2D and 3D versions of a video for 70 min. The participants experienced visual fatigue after viewing the 3D content. Measures such as subjective rating, response time, event-related potential latency, heartbeat-evoked potential (HEP) alpha power, and task-evoked pupillary response (TEPR) latency were significantly different. Multitrait-multimethod matrix analysis indicated that HEP and TEPR latency measures had stronger reliability and higher correlations with 3D cognitive fatigue than other measures. TEPR latency may be useful for quantitatively determining 3D visual fatigue, as it can be easily used to evaluate 3D visual fatigue using a non-contact method without measuring burden.


Assuntos
Astenopia/diagnóstico , Imageamento Tridimensional/métodos , Raios Infravermelhos , Fotografação/instrumentação , Pupila/fisiologia , Adulto , Astenopia/fisiopatologia , Cognição , Eletrocardiografia , Potenciais Evocados/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Adulto Jovem
8.
Physiol Behav ; 200: 148-158, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29679659

RESUMO

The purpose of this study was to measure emotional contagion, determine its direction, and compare the intensity between positive and negative contagion using the synchronization of heart rhythm pattern (HRP). A total of 64 undergraduate students (32 women and 32 men) participated in the experiment, and were randomly categorized as either leaders or followers. Followers were required to imitate the facial expression (happy and sad) of the leader (emotional contagion) or of a facial image (emotional non-contagion). We found that emotional contagion significantly increased the correlation coefficient between leaders and followers' HRP for both positive and negative emotions, but emotional non-contagion did not. There was no significant difference in leaders' HRP before and after contagion, while followers' HRP changed significantly. During emotional contagion, the correlation coefficient for negative emotion was significantly higher than for positive emotion. The proposed method could measure low or high emotional contagion and determine its direction quantitatively. In our application study, a sales manager (leader) transmitted a positive emotion to a sales employee (follower), and the groups are organized as HEC or LEC (high or low emotional contagion) groups by evaluating the intensity of emotional contagion based on HRP synchrony between them. HEC group's performance was enhanced compared to the LEC group.


Assuntos
Comércio , Emoções , Determinação da Frequência Cardíaca , Relações Interpessoais , Liderança , Comportamento Social , Adulto , Eletrocardiografia , Emoções/fisiologia , Feminino , Frequência Cardíaca , Determinação da Frequência Cardíaca/métodos , Humanos , Masculino , Distribuição Aleatória , Adulto Jovem
9.
Front Physiol ; 9: 1400, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30364205

RESUMO

Pupillary responses are associated with affective processing, cognitive function, perception, memory, attention, and other brain activities involving neural pathways. The present study aimed to develop a noncontact system to measure brain activity based on pupillary rhythms using an infra-red web camera. Electroencephalogram (EEG) signals and pupil imaging of 70 undergraduate volunteers (35 female, 35 male) were measured in response to sound stimuli designed to evoke arousal, relaxation, happiness, sadness, or neutral responses. This study successfully developed a real-time system that could detect an EEG spectral index (relative power: low beta in FP1; mid beta in FP1; SMR in FP1; beta in F3; high beta in F8; gamma P4; mu in C4) from pupillary rhythms using the synchronization phenomenon in harmonic frequency (1/100 f) between the pupil and brain oscillations. This method was effective in measuring and evaluating brain activity using a simple, low-cost, noncontact system, and may be an alternative to previous methods used to evaluate brain activity.

10.
Comput Intell Neurosci ; 2018: 6058065, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29861712

RESUMO

Feature of event-related potential (ERP) has not been completely understood and illiteracy problem remains unsolved. To this end, P300 peak has been used as the feature of ERP in most brain-computer interface applications, but subjects who do not show such peak are common. Recent development of convolutional neural network provides a way to analyze spatial and temporal features of ERP. Here, we train the convolutional neural network with 2 convolutional layers whose feature maps represented spatial and temporal features of event-related potential. We have found that nonilliterate subjects' ERP show high correlation between occipital lobe and parietal lobe, whereas illiterate subjects only show correlation between neural activities from frontal lobe and central lobe. The nonilliterates showed peaks in P300, P500, and P700, whereas illiterates mostly showed peaks in around P700. P700 was strong in both subjects. We found that P700 peak may be the key feature of ERP as it appears in both illiterate and nonilliterate subjects.


Assuntos
Interfaces Cérebro-Computador , Encéfalo/fisiologia , Potenciais Evocados , Alfabetização , Redes Neurais de Computação , Adulto , Feminino , Humanos , Curva de Aprendizado , Aprendizado de Máquina , Masculino , Testes Neuropsicológicos , Curva ROC , Semântica , Processamento de Sinais Assistido por Computador , Fatores de Tempo , Percepção Visual/fisiologia , Adulto Jovem
11.
Sensors (Basel) ; 18(5)2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29724006

RESUMO

Cardiac activity has been monitored continuously in daily life by virtue of advanced medical instruments with microelectromechanical system (MEMS) technology. Seismocardiography (SCG) has been considered to be free from the burden of measurement for cardiac activity, but it has been limited in its application in daily life. The most important issues regarding SCG are to overcome the limitations of motion artifacts due to the sensitivity of motion sensor. Although novel adaptive filters for noise cancellation have been developed, they depend on the researcher’s subjective decision. Convolutional neural networks (CNNs) can extract significant features from data automatically without a researcher’s subjective decision, so that signal processing has been recently replaced as CNNs. Thus, this study aimed to develop a novel method to enhance heart rate estimation from thoracic movement by CNNs. Thoracic movement was measured by six-axis accelerometer and gyroscope signals using a wearable sensor that can be worn by simply clipping on clothes. The dataset was collected from 30 participants (15 males, 15 females) using 12 measurement conditions according to two physical conditions (i.e., relaxed and aroused conditions), three body postures (i.e., sitting, standing, and supine), and six movement speeds (i.e., 3.2, 4.5, 5.8, 6.4, 8.5, and 10.3 km/h). The motion data (i.e., six-axis accelerometer and gyroscope) and heart rate (i.e., electrocardiogram (ECG)) were determined as the input data and labels in the dataset, respectively. The CNN model was developed based on VGG Net and optimized by testing according to network depth and data augmentation. The ensemble network of the VGG-16 without data augmentation and the VGG-19 with data augmentation was determined as optimal architecture for generalization. As a result, the proposed method showed higher accuracy than the previous SCG method using signal processing in most measurement conditions. The three main contributions are as follows: (1) the CNN model enhanced heart rate estimation with the benefits of automatic feature extraction from the data; (2) the proposed method was compared with the previous SCG method using signal processing; (3) the method was tested in 12 measurement conditions related to daily motion for a more practical application.


Assuntos
Frequência Cardíaca , Redes Neurais de Computação , Artefatos , Eletrocardiografia , Feminino , Humanos , Masculino , Processamento de Sinais Assistido por Computador
12.
Sensors (Basel) ; 18(1)2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29342958

RESUMO

Continuous cardiac monitoring has been developed to evaluate cardiac activity outside of clinical environments due to the advancement of novel instruments. Seismocardiography (SCG) is one of the vital components that could develop such a monitoring system. Although SCG has been presented with a lower accuracy, this novel cardiac indicator has been steadily proposed over traditional methods such as electrocardiography (ECG). Thus, it is necessary to develop an enhanced method by combining the significant cardiac indicators. In this study, the six-axis signals of accelerometer and gyroscope were measured and integrated by the L2 normalization and multi-dimensional kineticardiography (MKCG) approaches, respectively. The waveforms of accelerometer and gyroscope were standardized and combined via ensemble averaging, and the heart rate was calculated from the dominant frequency. Thirty participants (15 females) were asked to stand or sit in relaxed and aroused conditions. Their SCG was measured during the task. As a result, proposed method showed higher accuracy than traditional SCG methods in all measurement conditions. The three main contributions are as follows: (1) the ensemble averaging enhanced heart rate estimation with the benefits of the six-axis signals; (2) the proposed method was compared with the previous SCG method that employs fewer-axis; and (3) the method was tested in various measurement conditions for a more practical application.


Assuntos
Frequência Cardíaca , Eletrocardiografia , Feminino , Coração , Humanos , Masculino , Monitorização Fisiológica , Movimento
13.
Int J Psychophysiol ; 123: 179-198, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28757234

RESUMO

This study aims to develop a non-contact measurement technique for cardiac response that uses an infrared image of the patient's pupil. The pupil contraction rhythm is related to the autonomic balance and major organs (such as the heart) via a neural pathway. In this study, the response of the heart was determined by analyzing the pupillary rhythm based on the harmonic frequencies between them. Seventy undergraduate volunteers of both genders, (35 females and 35 males), with ages ranging between 20 and 30years (mean: 24.52±0.64years) were asked to conduct a simple conversation, perform slight movements, and experience sound stimuli to evoke arousal, relaxation, happiness, sadness, or a neutral mood in this experiment. Electrocardiograms and pupil images were measured and analyzed, and the harmonic frequencies were identified to determine the relational response. The cardiac time (heart rate (HR), beats per minute (BPM), the standard deviation of the normal-to-normal (NN) intervals (SDNN), the mean squared differences in the successive N-N intervals (rMSSD), and the percentage difference between adjacent normal interbeat (R-R) intervals>50 (pNN50)) and frequency (very low frequency (VLF), low frequency (LF), high frequency (HF), VLF/HF, and LF/HF) parameters were also observed with regard to the effects of the movement, conversation, and physiological state. The cardiac response was stable, showing less significance than the effects of the three conditions. Therefore, multi-cardiac measurements were successfully obtained from a simple, low-cost, non-invasive, and non-contact data acquisition method in this study.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Diagnóstico por Imagem/métodos , Frequência Cardíaca/fisiologia , Raios Infravermelhos , Pupila/fisiologia , Adulto , Sistema Nervoso Autônomo/diagnóstico por imagem , Eletrocardiografia , Feminino , Humanos , Masculino , Adulto Jovem
14.
Neuropsychologia ; 106: 7-20, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28827155

RESUMO

Previous psychophysiological assessments of mental workload have relied on the addition of visual or auditory stimuli. This study investigated the tactile ERP and EEG spectral power correlates of mental workload by relating limited-capacity involuntary attention allocation to changes in late positive potential (LPP) amplitude, alpha, and theta powers. We examined whether mental workload (high-level cognitive control) can be evaluated using somatosensory stimuli. Sixteen participants all performed three tasks of varying difficulty. Two dual n-back tasks (n = 1 and 2) were used to investigate the degree to which mental workload affected the LPP amplitudes and EEG spectral powers evoked by ignoring salient tactile stimuli. In control trials, tactile vibrations were applied at random without dual n-back tasks. Subjective mental workload of each task was rated using the NASA Task Load Index. LPP amplitudes at Pz were significantly smaller in the dual-2-back trials compared to control and dual-1-back trials. Significantly increased theta power at Fz and reduced alpha power at Pz were found in the dual-2-back condition compared to control and dual-1-back condition. There was no significant difference between control and dual-1-back trials. The same pattern was found for subjective ratings of cognitive workload. These results indicate that the dual-2-back task imposed a significantly greater mental workload, causing impaired cognitive-control functions. Our findings support the notion that selective attention mechanisms necessary for effectively allocating and modulating attentional resources are temporarily impaired during the mentally overloaded state.


Assuntos
Atenção/fisiologia , Potenciais Somatossensoriais Evocados/fisiologia , Processos Mentais/fisiologia , Desempenho Psicomotor/fisiologia , Córtex Somatossensorial/fisiologia , Estimulação Acústica , Adulto , Eletroencefalografia , Eletroculografia , Feminino , Humanos , Masculino , Estimulação Luminosa , Distribuição Aleatória , Tempo de Reação/fisiologia , Tato/fisiologia , Carga de Trabalho , Adulto Jovem
15.
Sensors (Basel) ; 15(4): 7913-32, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25835301

RESUMO

"Out of the body" tactile illusion refers to the phenomenon in which one can perceive tactility as if emanating from a location external to the body without any stimulator present there. Taking advantage of such a tactile illusion is one way to provide and realize richer interaction feedback without employing and placing actuators directly at all stimulation target points. However, to further explore its potential, it is important to better understand the underlying physiological and neural mechanism. As such, we measured the brain wave patterns during such tactile illusion and mapped out the corresponding brain activation areas. Participants were given stimulations at different levels with the intention to create veridical (i.e., non-illusory) and phantom sensations at different locations along an external hand-held virtual ruler. The experimental data and analysis indicate that both veridical and illusory sensations involve, among others, the parietal lobe, one of the most important components in the tactile information pathway. In addition, we found that as for the illusory sensation, there is an additional processing resulting in the delay for the ERP (event-related potential) and involvement by the limbic lobe. These point to regarding illusion as a memory and recognition task as a possible explanation. The present study demonstrated some basic understanding; how humans process "virtual" objects and the way associated tactile illusion is generated will be valuable for HCI (Human-Computer Interaction).


Assuntos
Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Humanos , Lobo Límbico/fisiologia , Percepção/fisiologia
16.
Int J Psychophysiol ; 97(2): 120-30, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25911524

RESUMO

The purpose of this study was to identify an evaluation method for 3D cognitive fatigue based on a heart-brain synchronization phenomenon known as the heartbeat evoked potential (HEP). Thirty undergraduate students (15 females) watched a video in both 2D and 3D for an hour. Because visual fatigue is related to cognitive load, the HEP was used as an indicator of communication between the heart and the brain and therefore of cognitive function; responses were compared after 2D and 3D viewing. At the standard EEG sites F3 and F4, the alpha activity of the first and second HEP components was significantly increased after 3D video viewing relative to 2D. This increase likely indicates that sensory input from 3D video requires heavy computation by the brain, stimulating heart activity. The conclusion is that the first and second HEP components are significant parameters that can quantitatively evaluate 3D visual fatigue. Further work is needed to uncover the cause of 3D visual fatigue.


Assuntos
Encéfalo/fisiopatologia , Cognição/fisiologia , Potenciais Evocados/fisiologia , Fadiga/patologia , Coração/fisiopatologia , Eletrocardiografia , Eletroencefalografia , Feminino , Humanos , Imageamento Tridimensional , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia
17.
J Child Adolesc Psychopharmacol ; 24(9): 501-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25369174

RESUMO

UNLABELLED: Abstract Objective: There is evidence that Korean red ginseng (KRG) can reduce the production of the adrenal corticosteroids, cortisol, and dehydroepiandrosterone (DHEA), and thus may be a viable treatment for attention-deficit/hyperactivity disorder (ADHD). The present randomized double-blind placebo-controlled clinical trial tested the effect of KRG on children with ADHD symptoms. METHODS: Subjects 6-15 years, who satisfied the inclusion criteria and had ADHD symptoms, were randomized into a KRG group (n=33) or a control group (n=37). The KRG group received one pouch of KRG (1g KRG extract/pouch) twice a day, and the control group received one pouch of placebo twice a day. At the 8 week point, the primary outcomes were the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria for inattention and hyperactivity scale scores, which were measured at baseline and 8 weeks after starting treatment. Secondary outcomes were quantitative electroencephalography theta/beta ratio (QEEG TBR) (measured at baseline and week 8) and salivary cortisol and DHEA levels (measured at baseline and at 4 and 8 weeks). RESULTS: The baseline characteristics of the KRG and control groups were not statistically different. The mean ages of the KRG and control groups were 10.94±2.26 and 10.86±2.41, respectively. The KRG group had significantly decreased inattention/hyperactivity scores compared with the control group at week 8 (least squared means of the differences in inattention adjusted for baseline scores: -2.25 vs. -1.24, p=0.048; hyperactivity: -1.53 vs. -0.61, p=0.047). The KRG group had significantly decreased QEEG TBR compared with the control group (least squared means of the differences: -0.94 vs. -0.14, p=0.001). However, neither the KRG group nor the control group exhibited significant differences in salivary cortisol or DHEA levels at week 8 compared with the baseline levels. No serious adverse events were reported in either group. CONCLUSIONS: These results suggest that KRG extract may be an effective and safe alternative treatment for children with inattention and hyperactivity/impulsivity symptoms. Further studies to investigate the efficacy and safety of KRG are warranted.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Panax , Extratos Vegetais/uso terapêutico , Adolescente , Criança , Desidroepiandrosterona/análise , Método Duplo-Cego , Eletroencefalografia/efeitos dos fármacos , Feminino , Humanos , Hidrocortisona/análise , Coreia (Geográfico) , Masculino , Extratos Vegetais/efeitos adversos , Saliva/química
18.
Sensors (Basel) ; 13(10): 13054-62, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-24077321

RESUMO

Previous research has indicated that viewing 3D displays may induce greater visual fatigue than viewing 2D displays. Whether viewing 3D displays can evoke measureable emotional responses, however, is uncertain. In the present study, we examined autonomic nervous system responses in subjects viewing 2D or 3D displays. Autonomic responses were quantified in each subject by heart rate, galvanic skin response, and skin temperature. Viewers of both 2D and 3D displays showed strong positive correlations with heart rate, which indicated little differences between groups. In contrast, galvanic skin response and skin temperature showed weak positive correlations with average difference between viewing 2D and 3D. We suggest that galvanic skin response and skin temperature can be used to measure and compare autonomic nervous responses in subjects viewing 2D and 3D displays.


Assuntos
Astenopia/etiologia , Astenopia/fisiopatologia , Sistema Nervoso Autônomo/fisiopatologia , Reserva Cognitiva , Imageamento Tridimensional/efeitos adversos , Estimulação Luminosa/efeitos adversos , Adulto , Astenopia/diagnóstico , Apresentação de Dados , Feminino , Resposta Galvânica da Pele , Frequência Cardíaca , Humanos , Imageamento Tridimensional/métodos , Masculino , Estimulação Luminosa/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Temperatura Cutânea
19.
Front Hum Neurosci ; 7: 414, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23914165

RESUMO

This study is aimed to determine significant physiological parameters of brain and heart under meditative state, both in each activities and their dynamic correlations. Electrophysiological changes in response to meditation were explored in 12 healthy volunteers who completed 8 weeks of a basic training course in autogenic meditation. Heart coherence, representing the degree of ordering in oscillation of heart rhythm intervals, increased significantly during meditation. Relative EEG alpha power and alpha lagged coherence also increased. A significant slowing of parietal peak alpha frequency was observed. Parietal peak alpha power increased with increasing heart coherence during meditation, but no such relationship was observed during baseline. Average alpha lagged coherence also increased with increasing heart coherence during meditation, but weak opposite relationship was observed at baseline. Relative alpha power increased with increasing heart coherence during both meditation and baseline periods. Heart coherence can be a cardiac marker for the meditative state and also may be a general marker for the meditative state since heart coherence is strongly correlated with EEG alpha activities. It is expected that increasing heart coherence and the accompanying EEG alpha activations, heart brain synchronicity, would help recover physiological synchrony following a period of homeostatic depletion.

20.
Sensors (Basel) ; 13(3): 3454-72, 2013 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-23486216

RESUMO

Speller UI systems tend to be less accurate because of individual variation and the noise of EEG signals. Therefore, we propose a new method to combine the EEG signals and gaze-tracking. This research is novel in the following four aspects. First, two wearable devices are combined to simultaneously measure both the EEG signal and the gaze position. Second, the speller UI system usually has a 6 × 6 matrix of alphanumeric characters, which has disadvantage in that the number of characters is limited to 36. Thus, a 12 × 12 matrix that includes 144 characters is used. Third, in order to reduce the highlighting time of each of the 12 × 12 rows and columns, only the three rows and three columns (which are determined on the basis of the 3 × 3 area centered on the user's gaze position) are highlighted. Fourth, by analyzing the P300 EEG signal that is obtained only when each of the 3 × 3 rows and columns is highlighted, the accuracy of selecting the correct character is enhanced. The experimental results showed that the accuracy of proposed method was higher than the other methods.


Assuntos
Interfaces Cérebro-Computador , Encéfalo/diagnóstico por imagem , Eletroencefalografia/métodos , Processamento de Sinais Assistido por Computador , Eletrodos , Eletroencefalografia/instrumentação , Potencial Evocado P300 , Humanos , Percepção , Radiografia
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