Raffaella Folgieri Digital Information & Communication Departiment Constancy factors in visual perception 26/11/2010, Gjovik, Norway Why interest in visual perception? to investigate main factors in VR to understand boundaries between perception and cognitive processes to find instruments and methods to analyse human reaction to VR stimuli to understand emotional and cognitive involvement 1
MOTIVATION Investigating emotions in VR Aims: investigate emotions in VR Virthualis project Operators virtually immersed in production plant and in control room felt emotionally proven as immersed in real physical situation AIMS: reduce hazards in production plants and storage sites by addressing end-users practical safety issues through merging Human Factors (HF) knowledge and Virtual Reality(VR) technologies What are potentially influencing factors? VR AS A COMMUNICATION PROCESS between human beings mediated by computer systems interaction, visualization and other sensory stimuli to convey information Reality is not a intrinsic characteristic of VR is the result of a conventional way of coding information. A coding whose purpose is to bring the observer to the conclusion that the VR set is verisimile, i.e. similar-tothe-real-thing (or involves similar sensation?) 2
VISUAL PERCEPTION RELEVANCE Vision is the main sensorial system We need to focus on visual perception key factors Colors Immersivity: is the emotional stimulus key factor needs all the visual field Observer needs to explore actively all the visual fiels moving head and eyes The space and the depth perceptions become foundamental Eat me, Drink me What are key factors in spatial perception? 3
SPACE, SIZE AND SHAPE Spatial perception depends on multiple aspects We focus on three: Relative distances Size Shape We experiment some constancy effects, what are their origin? Perceptual? Cognitive? Perception viewpoint: understand relative distances and dimensions Interaction: foundamental role SPATIAL CONSTANCY 4
SHAPE CONSTANCY (1) Cognitive viewpoint: mental rotation or translation SHAPE CONSTANCY (2) In shape constancy effect we have a major role of high level brain activity: mental rotations! We assume that this activity can be detected in different brain areas, producing strong signals, to be identified and classified 5
EXPERIMENTS AND OBSERVATIONS To detect above activity we need to devise specific experiments To observe brain activity we could use: fmri Experiments on primate Both are invasive/difficult to use in VR environment 11 INVESTIGATION OBJECTIVES In a VR context: fmri not enough Need: uninvasive and portable instrument to investigate brain activity to identify brain areas activated in space and depth perception processes to correlate brain areas to active interactive exploration of spaces This will allows us to understand if in VR similarity to phisical reality is necessary find boundaries between perception and cognitive processes 12 6
EEG in VR: WHAT AND HOW Experiments setup VR similar to physical reality Reproducing stimuli through VR far from reality MODELS AND METHODS Computational models to analyse data from brain-motion and emotion sensors: Brain activity, cardio frequency, sweat, eye, arms and legs activities Data-fusion problem: Machine learning methods 7
MACHINE LEARNING Area of Artificial Intelligence concerned with the development of techniques which allow computers to "learn". Machine Learning: design and development of algorithms that allow computers to evolve behaviors based on empirical data (sensor data or databases). We want VR reacting to human perception! EXPECTED RESULTS Indications on brain areas involved in VR perception: relative distances and dimensions interaction Cognitive viewpoint: objects (mental) recognition 8
FINAL OBJECTIVE Experiments with EEG foundamental for the realization of algorithms allowing VR to adapt to human and vice-versa Thank you! 9