Active, Multimodal Perceivers of Complex Objects

1
Active, Multimodal Perceivers of Complex Objects

• We need a language and a framework within which
  to consider physiological and cognitive
  perceptual processes and to compare those
  processes within and between modalities.

2
Part 1 Actions of Perception

• detection is something there?
• intensity how strong is it ?
• pain is it strong enough to hurt?
• identification what is it?
• categorization what kind is it?
• enumeration how may are there?
• discrimination are two things the same or
  different?
• similarity/dissimilarity how are different
  things different?

3
Getting Stimulus Energies to the Receptors
Part 2 Processes of Perception
Distal Stimulus

• Distal Stimulus all energies emitted by the
  stimulus object
• usually multimodal
• usually emits energies we can not perceive
• beyond range or low energy

Environmental Modifications of Distal Stimulus

• Environmental Modifications physical changes
  to the emitted energies
• reflection/bouncing (e.g., mirror)
• refracting/bending (e.g., optical lens)
• non-specific filtering (e.g., distance)
• specific filtering (translucencies e.g., fog or
  gel)
• obstructing (opacities e.g., tree or hand)

Proximal Stimulus

• Proximal Stimulus the stimulus as delivered to
  the sensory receptors
• not all emitted object energies are delivered to
  all modalities
• most objects have multiple proximal stimuli
  (i.e., multimodal)

4
Processing those Energies
Transduction

• Transduction translation of stimulus energies
  that arrive at the sensory receptors into neural
  code
• modality-energy specific
• energy must be supra threshold

Transmission
Processing
Transmission passive delivery of the neural
code to the brain
Processing a vast amount of processing is done
changing or augmenting the neural code, before
it reaches the brain
Brain
Brain -- where neural codes from different
modalities are combined with memory, expectation,
affect to produce final perception
5

• Part 3 Egon Brunswicks Lens Model
• designed to describe active decision-making
  processes as a combination of analysis and
  synthesis steps

Any distal stimulus can be analyzed into its
elemental/energy parts
The sensed elements are synthesized into
perceptions
Proximal Stimulus
Physical Element
Physical Element
Proximal Stimulus
Distal Stimulus
Perceived Object
Physical Element
Proximal Stimulus
Physical Element
Proximal Stimulus
Those elemental/energy parts are individually
perceived though not independently!!!
6
(No Transcript)
7
This model affords us great flexibility to
represent and consider how perceptions work and
the things that influence perceptions
Environmental Modifications Reflecting,
refracting, nonspecific filtering, specific
filtering, obstruction

• Sensory Availability
• Modality specificity
• Sensory limitations

Proximal Stimulus
Physical Element
Physical Element
Proximal Stimulus
Perceived Object
Distal Stimulus
Physical Element
Proximal Stimulus
Physical Element
Proximal Stimulus
Notice there are two reasons that distal stimulus
information may not be part of the proximal
stimulus Environmental Modification and Sensory
Availability
8
This model affords us great flexibility to
represent and consider how perceptions work and
the things that influence perceptions

• Multimodality can easily be incorporated into the
  model
• Each element has a specific physical aspect
• Different physical aspects are sensed by
  different modalities

Vision
Proximal Stimulus
Physical Element
Proximal Stimulus
Distal Stimulus
Perceived Object
Physical Element
Proximal Stimulus
Physical Element
Touch
Proximal Stimulus
Hearing
9
This model affords us great flexibility to
represent and consider how perceptions work and
the things that influence perceptions
Perceptual Physiology Processes that process the
proximal stimulus Sensory, transfer brain
systems
Inner Psychophysics How neurological processes
drive perception
Proximal Stimulus
Physical Element
Physical Element
Proximal Stimulus
Inner Psychophysics
Distal Stimulus
Perceived Object
Physiology
Physical Element
Proximal Stimulus
Physical Element
Proximal Stimulus
Outer Psychophysics
10
This model affords us great flexibility to
represent and consider how perceptions work and
the things that influence perceptions
Top-Down cognitive processes that influence
perception
Memory
Physical Element
Proximal Stimulus
Expectations
Physical Element
Proximal Stimulus
Distal Stimulus
Perceived Object
Physical Element
Proximal Stimulus
Physical Element
Proximal Stimulus
Affect
Actions