Week 5 Lecture

Introduction

• Apology for the oversight regarding the week number, confirming it's week five.

• Today's focus: Perception, knowledge, and action.

• Discussion plan includes sensation and perception, development of perception in infancy, research methods for studying infants' perception, and understanding infants’ knowledge of their world.

Sensation and Perception

Definitions

• Sensation: Processes whereby sensory organs (eyes, ears, skin, mouth) receive information from the environment.

• Perception: The brain's interpretation and organization of sensory information, determining how we make sense of the stimuli.

Sensory Registers

• Eyes, ears, skin, mouth act as sensory registers that detect environmental stimuli.

• Perception involves organizing, identifying, and giving meaning to these sensations.

Theoretical Frameworks of Perceptual Development

• Nativist vs. Empiricist

  • Nativist: Inborn abilities to perceive forms and patterns (nature perspective).

  • Empiricist: Experience is crucial for constructing perception (nurture perspective).

• Gibsonian Perspective

  • Emphasizes a rich environmental context guiding accurate perception, suggesting perceptual systems evolve to understand the environment.

Perceptual Development

Importance of Learning

• As infants grow, they learn to focus on the most informative aspects of their environment, paralleling expertise development in particular fields.

Cognitive Position

• Top-down processing: Prior knowledge and reasoning influence perception.

• Bottom-up processing: Observation of the environment influences thought and perception.

Methods for Studying Infant Perception

• Infants cannot verbally express their perceptions; researchers utilize innovative methods.

Behavioral Observation

• Infants' sensory or perceptual abilities observed through behavior, autonomic responses (e.g., heart rate), and facial expressions.

Habituation and Dishabituation

• Habituation: Testing infants' discrimination between stimuli through decreased fixation over time.

  • Example: Infants looking less at previously shown stimuli but showing increased interest in a novel stimulus, indicating discrimination.

Preferential Looking Method

• Infants presented with pairs of stimuli, observing which they look at longer to infer preference and discrimination.

Other Methodologies

• Imitation: Noting infants' ability to imitate actions from models.

• Operant Conditioning: Conditioning infants to respond to stimuli.

• Evoked Potentials: Examining brain activity in response to stimuli.

Perceptual Abilities of Infants

Visual Perception

• Visual Acuity: Newborns have low clarity; it improves significantly by 12 months.

• Color Discrimination: Limited at birth, improves significantly by 3-6 months.

Object Perception

• Infants start to perceive objects as whole entities, demonstrating size and shape constancy over time.

• Depth Perception: Initially uncoordinated eyes; binocular vision develops by 4-5 months.

Depth Perception Research

• Gibson and Walk's Visual Cliff Experiment: Infants show fear towards deep sides, indicating developed depth perception.

Development of Hearing

• Infants respond better to louder sounds and higher frequencies; preference for maternal voices is evident.

• In utero listening capabilities established through studies linking maternal voice to newborn preference.

Chemical Senses: Taste and Smell

• Newborns distinguish between various tastes, preferring sweet and exhibiting recognition for maternal scents.

Intermodal Perception

• Combines different sensations to form unified perceptions.

• Infants can interact across sensory modalities, exploring objects utilizing multiple senses.

Concepts of Knowledge in Infants

Early Memory Studies

• Ravi Collier and Cuevas: Infants demonstrate memory recall abilities through operant conditioning tasks involving mobile rewards.

• Infants show improved recall abilities as they age, reliant on distributed training methods.

The Concept of Object Permanence

• Piaget's theory states object permanence emerges around 8-9 months; it is critical for social/emotional bonds.

• Violation of Expectation Technique developed as a means to test this concept in younger infants.

Conclusion

• Recap of sensation vs. perception, development of research methodologies, and sensory capabilities in infancy.

• Reminder to use references and cite appropriately in learning materials.