1. Basic Cognitive Processes - 2
Psych. 414
Prof. Jessica Sommerville

2. Infant perception Visual perception Auditory perception
Intermodal perception

3. Face perception
By 3 months look longer at face than non-face, and show a preference for familiar faces
After 6 months face perception becomes more adult-like
Orientation, gender, emotional expression, attractiveness
Faces as preferred stimuli from birth?
Preferential tracking of faces from birth
Innate template for detecting faces based on configurational elements

4. Auditory perception
Head-turn paradigm
HAS paradigm

5. Head-turn paradigm Hear noise
Uses operant conditioning -- esp useful for localization and discrimination
Hear noise
Reinforced for turning head in particular direction

6. High-amplitude sucking (HAS) paradigm
Baseline sucking
Reinforced for increases in sucking rate
Sucking wanes with repeated presentation (habituation)
Different sound: increased sucking?

7. Speech perception Preferences:
Speech over non-speech; infant-directed speech
Preference for mother’s voice: due to familiarity
From birth: Cat in the Hat study (DeCasper & Spence, 1986; txt p )

8. Speech perception Discriminations:
Categorical speech perception: differences between speech sounds are continuous -- we perceive them as categorical
Present in adults and infants
Initially discriminate speech sounds across all languages
Decline in non-native contrasts between 6 and 12 months of age
Matter of degree not overall loss
Categorical perception not unique to humans or speech

9. Intermodal perception
Recognition of common source of sensation; ability to match information across senses
Sights and sounds
By 3 months match voice to face based on sex, age, and mouth movements
Sights and feels
Match visual impression to touch by 1 month
Imitation (at birth)

11. Memory development: The traditional view
Recognition
Recall
Applying schemas to objects
Requires mental representation
Habituation/dishabituation
Deferred imitation
Operant conditioning
TIME
18 months

12. Recognition Familiarity with a reencountered stimulus
Habituation paradigms
Infants habituate to a repeated stimulus and dishabituate to a novel stimulus from birth
5 month-olds show a novelty preference for new faces and new objects after two weeks (Fagen, 1973; Fantz et al., 1975)
6 month olds remember dynamic stimulus from 3 months ago (Bahrick & Pickens, 1995)

13. Recognition
Operant conditioning paradigms (Rovee-Collier and colleagues)
Mobile task: 3 minute baseline (no reinforcement); 9-minute reinforcement period; expose babies to mobile later
3 month-old infants remember for 2 weeks
Initially, memories are highly specific

14. Recall
The ability to retrieve a representation from memory in the absence of cues
Measured via deferred imitation
- Infant watches action (no immediate imitation is allowed)
- Given opportunity to reproduce action at a later point in time
Piaget
Not until 18 months of age
Relies on mental representation

15. Recall But emerging evidence suggests that it develops earlier
First evident in 6-month-olds
By 9 months infants can reproduce an action they say 24 hours earlier (a subset up to 1 month)
23 month-olds imitate actions they saw modeled 1 full year ago

16. Memory development and the brain
Age-related changes between 6 months and 2 years in deferred imitation linked to brain development
Hippocampus
Develops early
Underlies deferred imitation of simple actions at 6 months
Long-term recall of more complex actions requires additional brain areas
Prefrontal lobe, temporal lobe