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TRANSCRIPT
Constancy factors in visual perception
Raffaella FolgieriDICo – Digital Information & Communication Departiment
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
MOTIVATION
DICo
Aims: investigate emotions in VR
What are potentially influencing factors?
• Investigating emotions in VR
Virthualis project
Operators virtually immersed in production plant and in control room felt emotionally provenas 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
VR AS A COMMUNICATION PROCESS
A coding whose purpose is to bring the observer to the conclusion that the VR set is verisimile, i.e. “similar-to-the-real-thing” (or involves similar sensation?)
DICo
• 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.
VISUAL PERCEPTION RELEVANCE
DICo
• 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
DICo
Eat me, Drink me…What are key factors in spatial perception?
SPACE, SIZE AND SHAPE
DICo
• 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?
SPATIAL CONSTANCY
DICo
Perception viewpoint:• understand relative
distances and dimensions
• Interaction: foundamental role
SHAPE CONSTANCY (1)
DICo
Cognitive viewpoint:
• mental rotation or translation
SHAPE CONSTANCY (2)
DICo
• 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
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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
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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
EEG in VR: WHAT AND HOW
DICo
• Experiments setup• VR similar to physical reality
• Reproducing stimuli through VR far from reality
MODELS AND METHODS
DICo
• 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
MACHINE LEARNING
DICo
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
DICo
Indications on brain areas involved in
• VR perception:
• relative distances and dimensions
• interaction
• Cognitive viewpoint:
• objects (mental) recognition
FINAL OBJECTIVE
DICo
Experiments with EEG foundamental for the
realization of algorithms allowing VR to
adapt to human and vice-versa
DICo
Thank you!