Human Development

1
Human Development

• Fundamental Issues in
• Developmental Psychology

2
Developmental Psychology

• Basic question What shapes the way we change
  over time?
• Focus on psychological changes across the entire
  life span
• Every area of psychology can be looked at from
  this perspective
• biological development
• social development
• cognitive / perceptual development
• personality development

3
Fundamental Issues Nature vs. Nurture

• What is role of heredity vs. environment in
  determining psychological makeup?
• Is your IQ inherited or determined by nutrition
  and early environment?
• Is there a criminal gene or does poverty lead
  to criminal behavior?
• Is sexual orientation a choice or genetically
  determined?
• These are some of our greatest societal debates
• Mistake to pose as either / or questions

4
Fundamental Issues Is Development Continuous?

• Development means change - change can be abrupt
  or gradual
• Two views of human development
• stage theories there are distinct phases to
  intellectual and personality development
• continuity development is continuous
• These views have been applied to social, personal
  and intellectual development

5
Fundamental Issues in Developmental Psychology

• Critical period - Are there periods when an
  individual is particularly sensitive to certain
  environmental experiences?
• Are the first hours after birth critical for
  parent-child bonding?
• Is first year critical for developing trust?
• Easier to learn a language before age 10?
• Are there individual differences in stages and
  critical periods?

6
Developmental Research Methods

• Cross-sectional - performance of people of
  different age groups is compared
• Longitudinal - performance of one group of people
  is assessed repeatedly over time
• Sequential - combines cross-sectional and
  longitudinal approaches in a single study

7
Physical and Psychological Development Related

• Physical development begins at conception
• Physical maturity sets limits on psychological
  ability
• visual system not fully functional at birth
• language system not functional until much later
• Prenatal environment can have lifetime influence
  on health and intellectual ability

8
Prenatal Development

• Conception - when a sperm penetrates the ovum
• Zygote - a fertilized egg
• Germinal period - first two weeks after
  conception
• Embryonic period - weeks three through eight
  after conception
• Fetal period - two months after conception until
  birth

9
Prenatal Influences on Development

• Teratogen - any agent that causes a birth defect
  (e.g., drugs, radiation, viruses)
• Fetal Alcohol Syndrome (FAS)
• cluster of defects occurring in infants born to
  mothers that drink heavily during pregnancy
• leading cause of mental retardation
• can be totally prevented by abstaining from
  alcohol during pregnancy

10
Infant Abilities and Perceptions

• What does an infant feel and perceive?
• William James said, booming, buzzing confusion.
  Was he right?
• Is infant vision just a blur?
• Is infant sound just buzzing and booming?
• He was probably wrong, but infants have limited
  ability to communicate, so it is hard to tell
  what they experience

11
Infant Abilities

• Infants are born with immature visual system
• can detect movement and large objects
• Other senses function well on day 1
• will orient to sounds
• turn away from unpleasant odors
• prefer sweet to sour tastes
• Born with a number of reflex behaviors

12
Infant Reflexes

• Rooting - turning the head and opening the mouth
  in the direction of a touch on the cheek
• Sucking - sucking rhythmically in response to
  oral stimulation
• Babinski - fanning and curling toes when foot is
  stroked

13
Infant Reflexes

• Moro - throwing the arms out, arching the back
  and bringing the arms together as if to hold onto
  something (in response to loud noise or sudden
  change in position of the head)
• Grasping - curling the fingers around an object

14
Methods for Studying Infants

• Infant reflexes provide insight into their mental
  life
• gaze duration related to visual perception
• head turning related to auditory attention
• sucking, reaching, kicking can be used to measure
  interest

15
Infant Perception

• Not just a blur or a buzz
• In first week
• will recognize their mothers smell
• will show preference for novel stimuli
• gaze at face-like pattern rather than similar non
  face-like pattern

16
Infant Perception

• Infants explore their environment in whatever way
  their physical development permits
• At 2-3 months will grasp object and put in mouth
  to explore
• At 3-4 months will manipulate object, examine it
  visually, selectively attend to novel objects or
  events

17
Infant Perception

• A basic question is how knowledge of the
  properties of physical objects arises
• object permanence
• objects cant pass through other objects
• dropped objects fall
• Research on infant selective attention
• measure gaze duration
• create physically impossible events
• infants notice at 3-4 months
• Depth perception- visual cliff

18
Summary

• Developmental psychology concerned with
  psychological change over the life span
• Issues are very broad
• heredity vs. environment
• stages vs. continuous change
• Are there critical periods?
• prenatal influences
• How much ability are we born with?