title: Brain response to a humanoid robot in areas implicated in the perception of human emotional gestures.
abstract: BACKGROUND
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  Motor resonance towards a humanoid robot, but not a human, display of facial emotion is increased when attention is directed towards judging emotions.
  
  
  CONCLUSIONS
  Artificial agents can be used to assess how factors like anthropomorphism affect neural response to the perception of human actions.
authors.affiliation: Wellcome Trust Centre for Neuroimaging, University College London, London, United Kingdom. tchamina@gmail.com
authors.forename: Thierry
authors.initials: T
authors.lastname: Chaminade
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Zecca
authors.forename: Sarah-Jayne
authors.initials: SJ
authors.lastname: Blakemore
authors.forename: Atsuo
authors.initials: A
authors.lastname: Takanishi
authors.forename: Chris D
authors.initials: CD
authors.lastname: Frith
authors.forename: Silvestro
authors.initials: S
authors.lastname: Micera
authors.forename: Paolo
authors.initials: P
authors.lastname: Dario
authors.forename: Giacomo
authors.initials: G
authors.lastname: Rizzolatti
authors.forename: Vittorio
authors.initials: V
authors.lastname: Gallese
authors.forename: Maria Alessandra
authors.initials: MA
authors.lastname: Umiltà
mesh_terms: D000328:Adult; D000786:Anger; D001921:Brain / Q000502:physiology*; D004644:Emotions; D005149:Facial Expression; D005260:Female; D005868:Gestures; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D012371:Robotics; D055815:Young Adult