Human Development – Lecture (Chapter 11)
Developmental Psychology Some Questions …
What does the world look like to a newborn infant? Can they make any sense
of their surroundings?
o Come up with ways to help individuals who are not capable of
When do infants first recognize their mothers?
o Their fathers?
o Themselves (in a mirror)?
Why do many 1-year-olds seem so attached to their mothers/fathers and
wary of strangers?
Why do you remember so little about the first two years of your life?
How much influence do genes have on a child's behaviors?
Are boys really different from girls?
o Sexual motivation?
What's with twins anyway? Are they really different from the rest of us?
o Tends to asks difference from a behavioral or developmental
Critical period concept suggests that the brain is set to acquire a function
during a limited period of time.
o Ie. Language individual from the age of 3-5 years old and put them
into a country with different language. The capacity of the 13-15 year
old that moves to another country will have a harder time.
o This is because of critical periods point in life where the brain is
able to learn and most receptive to learning a particular skill (in this
case language early in life)
If key experiences do not occur during a critical time period, the function
may not develop or may not be fully developed
o The case of Genie: a girl who was isolated until the age of 13.
Although Genie made some gains in language, her syntax never
approached normal levels. The case of Genie supports a critical
period for language acquisition (yet some point to her gains later in
o Measles can cause mental retardation if contracted during certain
fetal periods. Measles can causes changes in IQ. The brain is more
receptive to damage at one point of fetal development
o Useful for assessing age differences
o Not useful for examining age changes o Cohort Effect - Whatever behavior we are collecting in this year, could
be very specific to the experiment that this generation is going on for
o The problem is that each age group (cohort) has different life
o Follow the same individual over a period of time
o It is limiting because you are still focusing on that specific individual
when they are turning ages
o Takes into account a cross-sectional method as well as the
o Ie. Collecting information from a group of 7 year olds in 2013, then
another group of 7 years old in 2014
o Still sampling from the 7 year old while revisiting the same question
Prenatal Development (before birth)
Prenatal period has 3 phases
Germinal period: 1st two weeks after conception
o Implantation, fertilized egg travels in the uterus and plants itself to
the uterus wall
o **Placenta formation important in nutrient uptake, waste
elimination, gas exchanges
Embryonic period: 3rd to 8th weeks of gestation (pregnancy)
o Vital organs (e.g., heart, spine, brain) begin to form
Fetal period: from 9 weeks to birth
o Sex organs develop during the 3rd month of gestation
o Age of viability (22 weeks to 26 weeks) (even if there is a premature
birth, the fetus is still able to survive outside of the uterus)
Infant Reflexes (inborn motor responses)
Reflexes are innate motor responses elicited by critical stimuli.
o Reflexes are adaptive
Examples of infant reflexes
o Rooting reflex: A touch on the cheek induces the infant to move its
mouth toward the source of the touch (helps guide feeding).
o Sucking reflex: Tactile stimulation of the mouth produces rhythmic
Motor Development Can this individual meet a mild stone?
Shows that development is occurring in a healthy direction
o Mood, activity level, and emotional reactivity
***Mary Ainsworth (1913 - 1999): Attachment relationships depend on
sensitivity and responsiveness of caregivers to children’s needs
Came up with four kind of attachment relationships
o ***Secure: security, love, a