Kazuo Hiraki

Kazuo Hiraki
The University of Tokyo | Todai · Department of Systems Science

Keio University

About

196
Publications
20,566
Reads
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4,357
Citations
Introduction
Kazuo Hiraki currently works at the Department of Systems Science, The University of Tokyo. Kazuo does research in Cognitive Psychology, Developmental Psychology and Media Psychology. Their most recent publication is 'Classification of EEG Signals for a Hypnotrack BCI System'.

Publications

Publications (196)
Article
Full-text available
Third-party punishment of antisocial others is unique to humans and seems to be universal across cultures. However, its emergence in ontogeny remains unknown. We developed a participatory cognitive paradigm using gaze-contingency techniques, in which infants can use their gaze to affect agents displayed on a monitor. In this paradigm, fixation on a...
Conference Paper
The current study investigated how robot tutors influence brain activity during child-robot interaction (CRI) for learning of second language vocabulary. We gathered EEG signals from two groups of children; 1) Robot group (N=21) who listened to a storytelling social robot and learned French words, and 2) Display group (N=20) who listened to the sam...
Article
Full-text available
Advances in web technology and the widespread use of smartphones and PCs have proven that it is possible to optimize various services using personal data, such as location information and search history. While considerations of personal privacy and legal aspects lead to situations where data are monopolized by individual services and companies, a r...
Chapter
Social robots are being increasingly employed for educational purposes, such as second language tutoring. Past studies in Child-Robot Interaction (CRI) have demonstrated the positive effect of an embodied agent on engagement and consequently learning of the children. However, these studies commonly use subjective or behavioral metrics of engagement...
Conference Paper
Social robots are being increasingly employed for educational purposes, such as second language tutoring. Past studies in Child-Robot Interaction (CRI) have demonstrated the positive effect of an embodied agent on engagement and consequently learning of the children. However, these studies commonly use subjective or behavioral metrics of engagement...
Article
This study examined the effects of emotional distraction in the context of recalling stressful interpersonal events in daily life. Previous studies have revealed that distraction decreases unpleasant emotions. In this study, we examined whether distraction tasks decrease unpleasant task-related thoughts in addition to unpleasant emotions. Furthermo...
Conference Paper
In this study, we examined the effect of mindfulness meditation facilitated by human-robot interaction (HRI) on brain activity. EEG signals were collected from two groups of participants; Meditation group who practiced mindfulness meditation with a social robot and Control group who only listened to a lecture by the robot. We compared brain functio...
Article
Pupil diameter change is indicative of emotional processing. Most previous findings regarding pupillary response and emotion have reported that the pupil enlarges in response to the presentation of emotional perceptual stimuli (e.g., visual images) within several seconds. It is considered that such stimuli activate the sympathetic nervous system, l...
Article
Full-text available
Brain-computer interfaces (BCIs) have long been seen as control interfaces that translate changes in brain activity, produced either by means of a volitional modulation or in response to an external stimulation. However, recent trends in the BCI and neurofeedback research highlight passive monitoring of a user's brain activity in order to estimate...
Article
Full-text available
Although developmental science has always been evolving, these times of fast-paced and profound social and scientific changes easily lead to disori- enting fragmentation rather than coherent scien- tific advances. What directions should developmen- tal science pursue to meaningfully address real- world problems that impact human development through...
Article
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Several studies have demonstrated that perceiving an action influences the subsequent processing of action verbs. However, which characteristics of the perceived action are truly determinant to enable this influence is still unknown. The current study investigated the role of the agent executing an action in this action–language relationship. Parti...
Conference Paper
Mindfulness is the state of paying attention to the present moment on purpose and meditation is the technique to obtain this state. This study aims to develop a robot assistant that facilitates mindfulness training by means of a Brain-Computer Interface (BCI) system. To achieve this goal, we collected EEG signals from two groups of subjects engagin...
Preprint
Mindfulness is the state of paying attention to the present moment on purpose and meditation is the technique to obtain this state. This study aims to develop a robot assistant that facilitates mindfulness training by means of a Brain Computer Interface (BCI) system. To achieve this goal, we collected EEG signals from two groups of subjects engagin...
Article
Full-text available
Objective The ability to integrate audiovisual information matures late in adolescents, but its neuronal mechanism is still unknown. Recent studies showed that phase‐amplitude coupling (PAC) of neuronal oscillations, which is defined as the modulation of high‐frequency amplitude by low‐frequency phase, is associated with audiovisual integration in...
Article
Full-text available
Variation of information in the firing rate of neural population, as reflected in different frequency bands of electroencephalographic (EEG) time series, provides direct evidence for change in neural responses of the brain to hypnotic suggestibility. However, realization of an effective biomarker for spiking behaviour of neural population proves to...
Article
Full-text available
Appropriately handling and switching exploration of novel knowledge and exploitation of existing knowledge is a fundamental element of genuine innovation in society. Moreover, a mounting number of studies have suggested that such “ambidexterity” is associated not only with organizational performance but also with the human brain. Among these report...
Conference Paper
In this paper we present a lab study on robot abuse by children. 61 Japanese children of ages 7-9 interacted individually with Robovie, a social robot, in a context that promoted children's free disruptive behaviors towards the robot. We compared the robot's use of an adaptation of a parental discipline strategy, the so-called love-withdrawal techn...
Article
The current study examined whether cerebral blood flow (CBF) changes in the anterior ventral medial prefrontal cortex (VMPFC) represent responses to emotional stimuli instead of cognitive control of emotion during distraction tasks, as suggested by our previous near-infrared spectroscopy (NIRS) study. The functional distinction of MPFC regions is o...
Article
Full-text available
It has been shown that an averted gaze with emotional expression guides our attention toward a gazed-at location, and the effect of a gaze with fearful expression has been well-investigated. However, the findings are not consistent, and most studies used the manual response measure. Recent studies suggest that examining eye movements is more suitab...
Article
The relationship between temporal contiguity of mothers' teaching behaviors and children's imitation learning was investigated. Participants (2-year-old children) observed their mothers' demonstration of using novel toys over a double television system under live and delayed conditions. The dyads normally interacted in the live condition, whereas t...
Conference Paper
When is the best learning timing for a learner, and can we develop a system to tell each learner of their individual learning timing? In this paper, we describe the application of a consumer grade wearable sensor (activity tracker) to e-Learning. In considering a technique to estimate the relationship between a learner's learning timing and their p...
Conference Paper
People's responses to a hypnosis intervention is diverse and unpredictable. A system that predicts user's level of susceptibility from their electroencephalography (EEG) signals can be helpful in clinical hypnotherapy sessions. In this paper, we extracted differential entropy (DE) of the recorded EEG from two groups of subjects with high and low hy...
Article
External feedback plays an important role in adapting to the environment; however, feedback processing in preschoolers has not been fully understood. The present event-related brain potential (ERP) study sought to understand the influence of parental presence with encouragement on feedback processing by focusing on reward positivity (RewP: mean amp...
Patent
This patent relates to the design and implementation of a computational model that utilizes the EEG activity of human subjects' brain activity to detect the onset of the hypnotic state and to determine the human subjects' degree of suggestibility during the hypnosis session.
Chapter
We evaluate the humanlike-ness of humanoid robots using electroencephalography (EEG). As the activity of the human mirror-neuron system (MNS) is believed to reflect the humanlike-ness of observed agents, we compare the MNS activity of 17 participants while observing certain actions performed by a human, an extremely humanlike android, and a machine...
Chapter
This project aimed to better understand the possibilities and limitations of an artificial pedagogical agent. For example, could an agent be programmed into a robot or a computer to teach? If so, how should such an agent be designed? To answer these questions, we used an approach that integrated developmental cognitive science, information technolo...
Article
When near-infrared spectroscopy (NIRS) is used to measure emotion-related cerebral blood flow (CBF) changes in the prefrontal cortex regions, the functional distinction of CBF changes is often difficult because NIRS is unable to measure neural activity in deeper brain regions that play major roles in emotional processing. The CBF changes could repr...
Article
Full-text available
Protective interventions by a third party on the behalf of others are generally admired, and as such are associated with our notions of morality, justice and heroism 1, 2, 3, 4 . Indeed, stories involving such third-party interventions have pervaded popular culture throughout recorded human history, in myths, books and movies. The current developme...
Article
Recent studies have revealed that curiosity—seeking new information and experiences—can improve psychological and social functioning. However, the social nature of curiosity remains poorly understood. We tested whether curious people show better psychological adaptation because (1) they have less rejection sensitivity, and (2) they are less suscept...
Article
Full-text available
Rubber hand illusion (RHI) is an important phenomenon for the investigation of body ownership and self/other distinction. The illusion is promoted by the spatial and temporal contingencies of visual inputs near a fake hand and physical touches to the real hand. The neural basis of this phenomenon is not fully understood. We hypothesized that the RH...
Article
Full-text available
Though recent studies have elucidated the earliest mechanisms of processing in multisensory integration, our understanding of how multisensory integration of more sustained and complicated stimuli is implemented in higher-level association cortices is lacking. In this study, we used magnetoencephalography (MEG) to determine how neural oscillations...
Article
Full-text available
Recently, extremely humanlike robots called "androids" have been developed, some of which are already being used in the field of entertainment. In the context of psychological studies, androids are expected to be used in the future as fully controllable human stimuli to investigate human nature. In this study, we used an android to examine infant d...
Article
Full-text available
We performed two electroencephalogram (EEG) experiments to examine how humanoid robot appearance and motion affect human subjects' perception of the robots. Mu rhythm suppression of EEG, which is considered to reflect mirror neuron system (MNS) activation, was regarded as a neurological indicator of perceived human likeness. Video clips depicting u...
Article
Full-text available
Animated pedagogical agents are lifelike virtual characters designed to augment learning. A review of developmental psychology literature led to the hypothesis that the temporal contingency of such agents would promote human learning. We developed a Pedagogical Agent with Gaze Interaction (PAGI), an experimental animated pedagogical agent that enga...
Article
Multisensory integration is required to interpret information from multiple senses and then produce the appropriate behavioral output. Inverse effectiveness, a phenomenon in which weaker stimuli induce greater activation of multisensory neurons than do stronger stimuli, is an essential component of multisensory integration. The superior colliculus...
Article
Full-text available
It has been shown that preschool children can learn as well from video presentations as from live presentations in word acquisition, action imitation, and object searching. Several cognitive theories have been proposed to explain the developmental changes accompanying the onset of learning from TV, but the underlying neural mechanism is unclear. On...
Article
Full-text available
The neuropeptide oxytocin plays a central role in prosocial and parental behavior in non-human mammals as well as humans. It has been suggested that oxytocin may affect visual processing of infant faces and emotional reaction to infants. Healthy male volunteers (N = 13) were tested for their ability to detect infant or adult faces among adult or in...
Article
The present study examined how young children and adult participants activated inferior prefrontal regions when they were given different cognitive shifting tasks. Children and adults were given two versions of the Dimensional Change Card Sort task (the standard and advanced versions), and brain activations during the tasks were examined using near...
Article
Full-text available
Objective. This study examined the relationship between neural activity and executive function (EF) by near-infrared spectroscopy (NIRS). In addition, an oral reading span test (RST) was used to explore this association. Methods. Fifteen adults participated in the study. We used the RST and simple reading as the two tasks. Results. The RST score...
Conference Paper
In this study, we investigate the two effects of joint attention, building relationships and sharing recognition, in group interaction consisting of two robots and one person. The building relationship is focused on entrainment resulting from the two robots' gazing at one person, while the sharing recognition refers to an original effect of the joi...
Article
Full-text available
Gaze direction cues and facial expressions have been shown to influence object processing in infants. For example, infants around 12 months of age utilize others' gaze directions and facial expressions to regulate their own behaviour toward an ambiguous target (i.e., social referencing). However, the mechanism by which social signals influence over...
Article
Full-text available
This study investigated the neural processing underlying the cognitive control of emotions induced by the presentation of task-irrelevant emotional pictures before a working memory task. Previous studies have suggested that the cognitive control of emotion involves the prefrontal regions. Therefore, we measured the hemodynamic responses that occurr...
Article
Full-text available
Executive function (EF) refers to the higher-order cognitive control process for the attainment of a specific goal. There are several subcomponents of EF, such as inhibition, cognitive shifting, and working memory. Extensive neuroimaging research in adults has revealed that the lateral prefrontal cortex plays an important role in EF. Developmental...
Article
Full-text available
Evaluating the familiarity of faces is critical for social animals as it is the basis of individual recognition. In the present study, we examined how face familiarity is reflected in neural activities in our closest living relative, the chimpanzee. Skin-surface event-related brain potentials (ERPs) were measured while a fully awake chimpanzee obse...
Article
Full-text available
The purpose of this study was to assess the effect of short-term priming in perceptual anticipation tasks involving point-light biological motions. After the production or the observation of a relevant or an irrelevant movement (action vs. observation priming), 11 right-handed volunteers were asked to anticipate, as quickly and accurately as possib...
Article
Executive function refers to the ability to plan and execute task-relevant actions and to inhibit irrelevant actions for the attainment of a specific goal. Extensive adult neuroimaging research has revealed that the lateral prefrontal cortex plays an important role in executive function. Recently, developmental studies have shown behavioral evidenc...
Article
Full-text available
Advancement of non-invasive brain imaging techniques has allowed us to examine details of neural activities involved in affective processing in humans; however, no comparative data are available for chimpanzees, the closest living relatives of humans. In the present study, we measured event-related brain potentials in a fully awake adult chimpanzee...
Article
Full-text available
Previous studies have shown that early posterior components of event-related potentials (ERPs) are modulated by facial expressions. The goal of the current study was to investigate individual differences in the recognition of facial expressions by examining the relationship between ERP components and the discrimination of facial expressions. Pictur...
Data
psychological evaluation of the ATR Facial Expression Image Database and the number of facial stimuli used in the current study. (DOC)
Article
Failure of executive function (EF) is a core symptom of attention-deficit/hyperactivity disorder (ADHD). However, various results have been reported and sufficient evidence is lacking. In the present study, we evaluated the characteristics of children with ADHD using the Stroop task (ST) and reverse Stroop task (RST) that reflects the inhibition fu...
Article
Driver drowsiness is one of the important issues in our traffic society today. A lot of methods to estimate drowsiness and alert systems have been proposed so far. In this study, we executed a driving simulator experiment in order to clarify the effects of two kinds of drowsy driver alert systems, which are based on eye closure duration and heart r...
Article
Full-text available
Recent neurophysiological studies have shown that several human brain regions involved in executing actions are activated by merely observing such actions via a human, and not by a mechanical hand. At a behavioral level, observing a human's movements, but not those of a robot, significantly interferes with ongoing executed movements. However, it is...
Article
Full-text available
Characteristics of the human visual field are well known to be different in central (fovea) and peripheral areas. Existing computational models of visual saliency, however, do not take into account this biological evidence. The existing models compute visual saliency uniformly over the retina and, thus, have difficulty in accurately predicting the...