Cognitive development in infancy

Foetal development: 8 weeks -> Reflexes, responds to touch   12 weeks -> Vital organs formed    6 weeks ->Foetal movement felt  24 weeks -> Sucking reflex     28 -> Viable   30 -> REM

Prenatal sensory development:

• Touch = Sucks thumb, moves    Hearing = Infants hear mother's voice   
• Taste/smell = Amnioti fluid swallowed, olfactory sensors stimulated   Sight = Little visual

Proprioception: Sense of position of parts of body    Nocioception: Sense of pain                        Introspection: Sense of hunger, hot/cold feelings

• Low birth weight = Below 5.5 pounds   Pre-term = Below 37 weeks   Very pre-term = Below 32
• Increased levels of developmental difficulties: Hearing/visual, learning, social/behavioural

Synaptogenesis - Growth of synapses between neurons to create dense network to allow travel of signals 

Synapse elimination - To stop network becoming more dense/unefficient

Physical development:

• Birth: Reflexes & eye control (rooting reflex, stepping reflex, suckling)
• 6-7 months: Sits & reaches, motor control & understanding
• 11-13 months: Walking, first words, memory, motor control, balance

Proto-language = Early signs of language, no meaning, just rhythm

• DeCasper & Spence (1986): Infants prefer stories read to them in the womb
• Revee - Coller et al (1997): Infants learn to mobe + connections btwn actions & effects

Depth perception: Gibson & Walk, 1960: Distress when crawling over visual cliff (perception)

Habituation: Slater, Morrison & Rose, 1983: Look for less time after repetition, habituate then dishabituate. Induces visual references, tests wider variety of stimuli. Shows memory/learning.

Piaget --> Start as egocentric, NO object permanance. Sensori-motor knowledge limited to senses

Object permanence: 0-1 = none    

• 1-4m = Objects -> actions. Link perceptual inputs -> ideas
• 4-8m = Search for partially hidden objects (understand objects)
• 8-12m = Search, not A-B error (look in location A, even when it's in B)
• 12-18m = Hate invisible displacement (will search after object disappearance)
• 18-24m = Object permanence

Baillargeon & Graber, 1987: Against Piliavin - Piaget's tasks are too demanding. Violation of expectations. 5 1/2 object permanence

• Piaget makes infants synchronise watching, remembering & reaching which is too complex to keep track

Hood & Williats, 1986: Lights extinguished so object disappears, still show object permanence

• Show infants knowledge is more sophisticated - many aspects are learned.

Preferential looking, Fantz, 1961:

• Time spent fixating on 2 objects presented measured, which is looked at for longer?
• Poor vision, so like bold, bright, contrast and symmetry.

Violation of expectation:

Single visual stimulus. Looking time measured between trials. Adults expect it, babies dont

Visual/auditory perception:

• Innate tuning, human voice, focal distance
• Preference for females
• Vision improves in weeks and sound perception changes