Chapter 11: Human Development
- Both biological and environmental factors affect how one develops
Parental practices (eg. How a baby is positioned to sleep) affects motor
People are products of BOTH nature and nurture; thus the whole dichotomy
of one being right is WRONG
Embryo- baby starts developing organs; fetus- baby grows and looks like
human; baby- able to survive outside womb
Hormones in the womb have effects on the baby. Eg. If mother is depressed
or anxious, can cause light weight babies.
In a study, found that levels of testosterone are correlated with range of
behaviours later in childhood.
Teratogens- agents that can cause abnormal development in the womb;
length and amount of exposure results to the deformity of the child. Eg. Fetal
Babies have a variety of reflexes that aid survival, eg. Grasping reflex, rooting
reflex (sucking). As well, have better hearing than visual when born.
Brain growth has 2 important aspects:
o 1. Specific areas within the brain mature and become functional
o 2. Regions of the brain learn to communicate together through
synaptic connections. – myelination of the ‘wiring’ leads to faster
signal transmission. Thus, hearing at birth is fully myelinated.
Synaptic Pruning- ‘use it or lose it’ effect. Once connections between parts of
the brain are established, myelination makes it permanent. This causes the
brain to grow over time.
Critical Period is the time in which connections between parts of the brain is
most easily made and so learning is easiest then. Critical period hypothesis
states that environmental input is important but it is ultimately biology that
determines when an organism needs to receive input to make us of it.
From early childhood, children develop attachment: an intimate connection
between ppl that persist over time and gives the feeling of security and
The fact that adults make extreme facial expressions and talk in high pitch
allows the relationship between adult and baby intact.
Attachment is adaptive and those who experience it have higher chance of
survival. Hormone oxytocin is released
Attachment occurs for both humans and other animals. Process in which
specie attaches self and follow the object = imprinting. Eg. Goose and man.
Harry Harlow did the experiment with the two mothers and the monkey.
Study ended up rejecting initial idea of mother-as-food theory that
established mother-child attachment.
Children display various attachment styles:
o 1. Secure attachment (most common)- if attachment figure leaves the
child is sad, but once comes back is happy.
o 2. Avoidant attachment- when attachment figure returns, child shows
ignorance towards figure. This is a result of parents who are rejecting.
o 3. Anxious-ambivalent attachment- child clings to figure while trying
to hit the person. This is a result of parents who have inconsistent
New York longitudinal study found that child temperment and parents
behaviours are the most important in determining social development. Eg.
Moody ppl have hard time adapting to new situations.
Best parenting style takes into account own personality, child temperament,
Children learn through their senses. Infants tend to look more at interesting
stimuli and they look at new stimuli longer than old (orienting reflex). This
was tested through the preferential looking technique (eg. The black and
white vs. black and grey infant test).
Fox’s experiment for binocular disparity: Another study proved that visual
acuity is most-likely due to the development of visual cortex and
development of cones in retina.
Assimilation- process through which new experience replaces old schema
Accommodation is process which schema is adapted or expanded to
incorporate new experience.
Piaget stated that children go through 4 stages of development:
o (2)Sensorimotor stage: children acquire info about world through
senses and that they react reflexively to objects which later develops
schemas (eg. Sucking sucking various objects (assimilation), but
not the same experience (accommodation). They experience object
permanence * key accomplishment.
o ( 7) preoperational Stage: children have the ability to think about
objects not in their immediate view have developed conceptual
models of how the world works. Symbolic thinking begins, not logic.
No understanding of law of conservation (big and small glass with
same amount of water story)
o ( 12) Concrete Operational Stage: children begin to understand the
operational view of things. That an action is reversible enables the
child to understand concepts and conservation.
o ( adult) Formal Operational stage: involves abstract thinking. Using
logic. Eg. Study of clear water and one coloured water.
Problems with Piagets Theories:
o Children actually have innate knowledge. That they have cognitive
skills eg. When something looks odd, they often stare at it longer. They
have basic knowledge of laws of physics (eg. Movement – rod test;
also the stability test of taking off objects). Also, have mathematical
thinking. (understand concept of more than and less than – m&m
Infantile amnesia- inability to remember events from early childhood.
Source amnesia- unable to recall where something was learned.
Children tend to confabulate (make things up)
Theory of the mind: ability to explain and predict other people’s behaviour as
a result of recognizing mental state. (Piaget thought that young children
didn’t understand how others think (egocentric)). Studies show otherwise-
eg. The dumbbell test- infants mimic but not exact movements (eg. Slipping
o False belief test- eg. When you see someone put something in a
specific spot, you believe that when you check that spot, that object
would stay there.
o ALL OF THESE DEVELOP AS THE FRONTAL LOBE DEVELOPS
Genie (girl in that story) proves that social interaction between infant and
caregiver are essential to understanding other people and the ability to
Performatives- when babies try to mimic words- eg. Hello but sound more
As children grow older, they develop more language, leading to telegraphic
speech (throw ball, all gone).
Chromsky’s Theory states that we tend to remember the underlying meaning
of sentences (deep structure) vs. surface structure. Idea proved right when
attempted to get monkeys to learn language. Difficult because they are
unable to understand the underlying meaning.
Sensitive periods are times in which language is most easily learned.
In a study where questionnaires were given to participants- those who rated
self high on stereotypical traits of masculinity or femininity were labeled as
Masculine/Feminine. Those who rated in between – androgynous.
Situation alters gender-related response – eg. Talking to bf vs. good friend.