Perceptual Development

Role of Perception in CogDev

• Constructivist nature of CogDev: child as “builder” of thought

• How do we as adults construct thought in the context of perception

  • Creating something that is not real there…

    • Perceiving optical illusions

    • Ex. Moon illusion (angular size vs physical size) (depth cues)

Most all input for cognition (thought) is external

• Early in life, infants’ “consumption” of sights, sounds, touch, etc. shape thought…

• These thoughts then guide action

• This “cycle” builds new knowledge memory with increasing complexity

Percpetual System

• Has 3 main functions

  • Detect that a stimulus is present

  • Detect changes in a stimulus

  • Identify what gave rise to the perception

• Step 3 is why sensation and perception is central to CogDev

Sensation vs Perception

• Distal stimulus is processed… becomes a proximal stimulus

• We do more than “see: what is out there - we interpret it 

• We are not subject to naive realism (perceive the world objectively)

• Perception is the psychological process (organization + interpretation)

Early Perceptual Development

• Debates on nature/nurture… pre-wired vs learned

• No debate about the pre wired nature of sensation while perception involves both

• Soon after birth, infants have “in place” the critical apparatus for early perception

Early Perceptual Development: Preferences

• Rapid CogDev supported by:

  • Attention-getting vs Attention holding

  • Activation or orienting reflex

  • Attending to informative parts (“meaning”) vs Uninformative parts

  • Preference for complex vs simplistic

  • Physiological changes (eye)… acuity

  • Motion tracking… future-oriented events (3 mths)

  • Colour (hues/boundaires) perception (2-3 mths)

  • Point-light walkers (4 mths)

  • Complex face perception (6 mths)

Early Perceptual Development: Systems Support

• How is relatively “poor” vision in the early neonatal period an “advantage” to our species?

  • Social-cultural aspects of CogDev + revolutionary links

• How do those “inputs” further shape CogDev

  • Key: draws caregivers into the visual field + example infant agency

Early Perceptual Development: Shift to Action

• From 6-7 mths, motor development plays an increasing role in CogDev - Why?

• Perceptual-Motor Integration (Intersensory - cross-modal…)

  • Vision-touch matching

  • Special case for haptic perception

  • Theoretical implications

Haptic Perception

• Haptic development plays a really important role in shaping development

• The use of specific hand/digit motions to “study” and apprehend object properties that are then transferred from the motor cortex area to visual memory subcortical areas (i.e., cross modality integration)

• Exploratory procedures

Exploratory Procedures

• Lateral motion: texture

• Pressure: hardness

• Static contact: temperature

• Unsupported holding: weight

• Enclosure: global shape, volume

• Contour following: global shape, exact shape

Theoretical Implications

• Excellent case for explaining how motor development can predict cognition (M→ C)

  • In contrast to the typical expectations in psychological research that would put cognition in front of action (C→ M)

• Excellent example that gives new credence to Piaget’s historical “constructivist” approach AND today’s greater focus on human agency