Developmental Lecture 3 - perceptual and motor development

Today’s lecture focuses on sensory motor development in infancy, connecting perception, knowledge, cognition, and motor skills.
Importance of understanding how these elements are interlinked in the developmental process.

Infants (0-2 years) are difficult to test due to their nonverbal and often uncalibrated reactions.
Developmental challenge: Infants are described as being in a state of 'blooming, buzzing confusion' (William James).
Key points:
- Testing motor behaviors can yield unreliable data due to variability.
- Responses such as facial expressions and heart rate changes can indicate states of attention.
- Infants quickly lose interest or become bored, complicating testing.

Motor behaviors evolve over the first two years:
- Reaching, sitting, crawling, and ultimately walking (around 14 months).
- More advanced motor exploration begins with vocalizations and interactions with their environment.
Critical behavior: Looking is the most stable reaction measured in infants; crucial for understanding preferential looking.

Preferential looking time is essential in studying infants’ capacity to differentiate between stimuli.
- Involves presenting two stimuli and measuring the duration of attention to determine preference.
- Example study: Presentation of scrambled versus regular faces. Infants showed a preference for regular faces, suggesting differentiation ability.
Misconception: More looking time doesn’t indicate preference but rather the ability to distinguish.
Statistical inference is only valid when conducted with a minimum group sample size due to individual variances.

Crossmodal preferential looking studies the integration of sensory inputs (e.g., vision and hearing).
Example: The Yellow Booties study where infants distinguish between their own legs and others based on movement synchronicity.
The implications of motor skills impacting perceptual development.

Investigates whether enhanced object manipulation (via sticky mittens) can promote perceptual and cognitive outcomes in infants.
Results indicated significant improvements in visual and tactile exploration and crossmodal integration after a relatively short intervention period (2 weeks).

Visual habituation technique evaluates infants' ability to recognize and learn from repeated stimuli.
Infants show reduced interest (habituation) and then renewed interest (dishabituation), indicating learning.

Infants are expected to look longer at unexpected outcomes, indicating prior knowledge of the physical world.
Notable study: Wynn's addition/subtraction experiments demonstrated that infants could represent numbers and addition concepts.

Motor skills are strongly linked to cognitive abilities:
- The visual cliff study shows infants learn to perceive their environments and make judgments based on crawling experience.
- Learning curves vary with mobility; experience with motion increases spatial awareness and environmental perception.

Cultural practices influence motor development significantly.
For instance, varying methods of holding or interacting with infants can affect their motor skill acquisition timeline.
Example: Traditional practices in Tajikistan versus western approaches showcase diverse developmental trajectories.

Essential that milestones in motor development are utilized flexibly rather than rigidly, as developmental paths can vary greatly.
Importance of integrating cultural considerations and individual differences when evaluating development.