Presence: The debate between constructive cognition and ecological perception.

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Presence The debate between constructive
cognition and ecological perception.

• Nunez, D. Blake, E. (2003) Conceptual Priming
  as a Determinant of Presence in Virtual
  Environments, ACM Database.

Vicki Peace, Sian Pegler, Helen Poyer and Laura
Ringham
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Overview

• What is presence?
• How is presence explained?
• Ecological v Constructive Cognition
• Case Study
• Issues of measurement
• Conclusions and Questions

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What is presence?

• Presence is the idea of being there
• the degree to which the virtual environment
  dominates over the real environment as the
  basis for thought
• (Nunez and Blake, 2003)

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Where is the controversy?

• In general, presence is a controversial area.
• Many debates
• What actually is presence?
• How can presence be measured/evaluated?
• Does presence have an influence on tasks?
• SELECTED DEBATE What is the basis of presence?
• Ecological v Constructive Cognition

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Basis of Presence?Constructive v Ecological

• CONSTRUCTIVE COGNITION
• Eysenk Keane (1995)
• Higher level processing
• Top-Down
• Mental processing MOST important
• Perception and schemata
• Presence obtained as a process of mental
  processes interacting with sensory information

• ECOLOGICAL PERCEPTION
• Gibson (1979)
• Direct Perception
• Bottom-Up
• Sensory info MOST important
• Affordances
• Presence due to individuals perception of sensory
  information and action within their environment.

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The Case Study 1

• Conceptual Priming as a Determinant of Presence
  in Virtual Environment.
• Nunez and Blake (2003)
• Aim to determine if presence is actually
  constructed by the user or if it simply arises
  from sensory stimulation only.
• The study tested two hypotheses
• 1. If a user has active schemata which are
  related to the VE which the user is
  experiencing, then the user will experience more
  presence
• 2. If the VE is rendered on a higher
  fidelity display system, the user will experience
  more presence

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The Case Study 2

• The experiment had a 2x2 factorial ANOVA design
• Stimulus quality of VE display system
• Conceptual priming
• Two levels were used for each variable
• The dependant variable was presence
• 55 undergraduate participants
• Each participant took part in two experiment
  sessions, exploring two different VE and filling
  in two sets of presence questionnaires.

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Monastery VE
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Hospital VE
Figure 4 Hospital VE ward room in low stimulus
quality
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The Case Study 3

• Hardware
• Non-immersive, desktop-based systems
• Software
• VE exploration tool DAVE
• VEs
• Training environment
• Medieval European Monastery
• Hospital
• Priming
• Printed booklets either related to or not related
  to the theme of the VE

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The Case Study 4

• Measures
• Presence Questionnaire of Witmer Singer
• Presence Scale of Slater, Usoh Steed
• Procedure
• Instruction and training stage
• Priming stage
• Exploration stage
• Questionnaire stage
• Second iteration

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Results

• Relevant Prime Hospital or Monastery
• High presence in high quality environment
• Lower presence in low quality environment.
• Irrelevant Prime Steam Trains
• Presence similar between quality
• Interaction of Priming and Stimulus Quality
• Priming mediated experience of presence
• In high quality context prime enhanced
  presence.
• In low quality context prime reduced presence.

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Conclusions

• Mental state of user influences their experience
  of presence.
• But only in certain instances therefore
• Presence is not a scaled sum of sensory
  components.
• Presence is constructed through both sensory
  inputs and users mental context.
• Explained in terms of schemata activation
• Priming pre-allocates processing resources to
  related perceptions.
• In Irrelevant Condition processing of unrelated
  perceptions is difficult schemata deactivation
• In High Quality Condition enhanced processing
  smooths over inconsistencies
• In Low Quality Condition fit isnt good enough
  for enhanced processing OR bad enough for
  schemata deactivation poor processing

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What does this add to the debate?

• Support for more recent constructive concepts of
  perception (Eysenk Keane) over ecological
  perception (Gibson)
• Higher processes have a mediating role in the
  experience of presence
• Howeverboth views have explanatory power.

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Critique

• Criticisms of study
• No measurement of stimulus quality or intensity
  of priming provided
• Measurement of presence based on pen and paper
  questionnaires
• Lack of an effective measure of presence

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Measurement of Presence Other methods

• Objective Measures
• - Measurement of physiological and behavioural
  responses
• Qualitative or Ethnographic Approaches
• - In depth studies
• A Stochastic Model of Presence
• - Participants required to report whenever a
  break in presence occurs while they are present
  in the VE

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References

• Eysenk, M.W. Keane, M.T. (1995) Cognitive
  Psychology A Students Handbook. Hove Psychology
  Press
• Gibson, J.J. (1979) The Ecological Approach to
  Perception, Houghton-Mifflin. Boston.
• Nunez, D. Blake, E. (2001) Cognitive Presence
  as a unified concept of virtual reality
  effectiveness. Proceedings AFRIGRAPH 2001, p.
  115-8
• Nunez, D. Blake, E. (2003) Conceptual Priming
  as a Determinant of Presence in Virtual
  Environments, ACM Database
• Witmer, B.G and Singer, M.J. (1998) Measuring
  Presence in Virtual Environments A Presence
  Questionnaire, Presence Teleoperators and
  Virtual Environments, 7(3), 225-240.
• Slater, M., Usoh, M., Steed, A. (1994) Depth of
  Presence in Immersive Virtual Environments,
  Presence Teleoperators and Virtual Environments,
  MIT Press 3(2), 130-144.