30 research outputs found
A dynamic neural field approach to natural and efficient human-robot collaboration
A major challenge in modern robotics is the design of autonomous robots
that are able to cooperate with people in their daily tasks in a human-like way. We
address the challenge of natural human-robot interactions by using the theoretical
framework of dynamic neural fields (DNFs) to develop processing architectures that
are based on neuro-cognitive mechanisms supporting human joint action. By explaining
the emergence of self-stabilized activity in neuronal populations, dynamic
field theory provides a systematic way to endow a robot with crucial cognitive functions
such as working memory, prediction and decision making . The DNF architecture
for joint action is organized as a large scale network of reciprocally connected
neuronal populations that encode in their firing patterns specific motor behaviors,
action goals, contextual cues and shared task knowledge. Ultimately, it implements
a context-dependent mapping from observed actions of the human onto adequate
complementary behaviors that takes into account the inferred goal of the co-actor.
We present results of flexible and fluent human-robot cooperation in a task in which
the team has to assemble a toy object from its components.The present research was conducted in the context of the fp6-IST2 EU-IP
Project JAST (proj. nr. 003747) and partly financed by the FCT grants POCI/V.5/A0119/2005 and
CONC-REEQ/17/2001. We would like to thank Luis Louro, Emanuel Sousa, Flora Ferreira, Eliana
Costa e Silva, Rui Silva and Toni Machado for their assistance during the robotic experiment
Embodying the camera: An EEG study on the effect of camera movements on film spectators' sensorimotor cortex activation
One key feature of film consists in its power to bodily engage the viewer. Previous research has suggested lens and camera movements to be among the most effective stylistic devices involved in such engagement. In an EEG experiment we assessed the role of such movements in modulating specific spectators' neural and experiential responses, likely reflecting such engagement. We produced short video clips of an empty room with a still, a zooming and a moving camera (steadicam) that might simulate the movement of an observer in different ways. We found an event related desynchronization of the beta components of the rolandic mu rhythm that was stronger for the clips produced with steadicam than for those produced with a still or zooming camera. No equivalent modulation in the attention related occipital areas was found, thus confirming the sensorimotor nature of spectators' neural responses to the film clips. The present study provides the first empirical evidence that filmic means such as camera movements alone can modulate spectators' bodily engagement with film
Brain response to a humanoid robot in areas implicated in the perception of human emotional gestures
The humanoid robot WE4-RII was designed to express human emotions in order to improve human-robot interaction. We can read the emotions depicted in its gestures, yet might utilize different neural processes than those used for reading the emotions in human agents.Here, fMRI was used to assess how brain areas activated by the perception of human basic emotions (facial expression of Anger, Joy, Disgust) and silent speech respond to a humanoid robot impersonating the same emotions, while participants were instructed to attend either to the emotion or to the motion depicted.Increased responses to robot compared to human stimuli in the occipital and posterior temporal cortices suggest additional visual processing when perceiving a mechanical anthropomorphic agent. In contrast, activity in cortical areas endowed with mirror properties, like left Broca's area for the perception of speech, and in the processing of emotions like the left anterior insula for the perception of disgust and the orbitofrontal cortex for the perception of anger, is reduced for robot stimuli, suggesting lesser resonance with the mechanical agent. Finally, instructions to explicitly attend to the emotion significantly increased response to robot, but not human facial expressions in the anterior part of the left inferior frontal gyrus, a neural marker of motor resonance.Motor resonance towards a humanoid robot, but not a human, display of facial emotion is increased when attention is directed towards judging emotions.Artificial agents can be used to assess how factors like anthropomorphism affect neural response to the perception of human actions
Supplementary Material for: Mirroring the Self: Testing Neurophysiological Correlates of Disturbed Self-Experience in Schizophrenia Spectrum
<p><b><i>Background:</i></b> Self-disorders (SDs) have been described as
a core schizophrenia spectrum vulnerability phenotype, both in classic
and contemporary psychopathological literature. However, such a core
phenotype has not yet been investigated adopting a trans-domain approach
that combines the phenomenological and the neurophysiological levels of
analysis. The aim of this study is to investigate the relation between
SDs and subtle, schizophrenia-specific impairments of emotional
resonance that are supposed to reflect abnormalities in the mirror
neurons mechanism. Specifically, we tested whether electromyographic
response to emotional stimuli (i.e. a proxy for subtle changes in facial
mimicry and related motor resonance mechanisms) would predict the
occurrence of anomalous subjective experiences (i.e. SDs). <b><i>Sampling and Methods:</i></b>
Eighteen schizophrenia spectrum (SzSp) patients underwent a
comprehensive psychopathological examination and were contextually
tested with a multimodal paradigm, recording facial electromyographic
activity of muscles in response to positive and negative emotional
stimuli. Experiential anomalies were explored with the Bonn Scale for
the Assessment of Basic Symptoms (BSABS) and then condensed into
rational subscales mapping SzSp anomalous self-experiences. <b><i>Results:</i></b>
SzSp patients showed an imbalance in emotional motor resonance with a
selective bias toward negative stimuli, as well as a multisensory
integration impairment. Multiple regression analysis showed that
electromyographic facial reactions in response to negative stimuli
presented in auditory modality specifically and strongly correlated with
SD subscore. <b><i>Conclusions:</i></b> The study confirms the
potential of SDs as target phenotype for neurobiological research and
encourages research into disturbed motor/emotional resonance as possible
body-level correlate of disturbed subjective experiences in SzSp.</p