Dev psych lecture #1 info: nature vs nurture

Dev psych def

The scientific study of how and why humans change [biologically, psychologically] over the course of their life (“Developmental Psychology, 2021)

5 major issues in dev psych

• Nature or nurture?

• Sensitive/critical periods?

• Continuity vs discontinuity?

• Stability vs change

• Normative (typical) vs non-normative (atypical) events

Nativism + example capacity + theorist

The idea that there are biological predisposed/innate capacities

• E.g. language (Noam Chomsky)

Empiricism def + theorist

Knowledge from experience

• Tabula rasa (John Locke)

Infants + vision (2)

• Binocular vision ~14 weeks

• Depth perception ~ 6 months

• Visual acuity from blurry to clear ~1-12 months

• Preference for high contrast patterns patterns + faces ~3 months

Infants + taste (3)

• Distinctive reactions to sweet, sour, salty + bitter ~2 hours after birth

• Sweet vs sour discimination ~2 days

• Taste preference for sweet ~first few days after birth

Infants + smell (1)

• Can recognise mother’s smell + anise ~2 days old

Infants + hearing (3)

• Turn in direction of noise ~birth

• Recognise mother’s voice ~birth

• Distinguish between similar sounds ~1 month

What infants like

Infant skills

Born with:

• Rooting reflex → helps locate food

• Sucking reflex → helps to get food

Motor milestones (3)

• Head control ~2-3 months

• Sitting ~months later

• Standing/walking then running

Learning in the womb

• Evidence foetuses can hear in womb

Intelligence heritability estimate

~70% of variation due to genes

Value of monozygotic twin studies

• Useful for attempting to disentangle nature/nurture effects

Important note for twin studies

• Some similarities may be due to twins evoking similar response from others (environmental) rather than just genetic

Minnesota twin study

• Found separated identical twins had uncanny similarities