Chapter 4

Developmental Psychology

People of different ages have diverse thoughts, needs, and wants that are important to them at that time.

For example, none of you are worried about paying the mortgage and your parents are not worried about what to wear to impress that cute boy/girl

Some psychologists devote their lives to studying the changes people go through throughout

their lifetime

This branch of psychology is called…

Developmental Psychology Developmental Psychology

– The study of how our behavior and thoughts change over time

– Think of it this way …

• the study of humans WOMB to TOMBWOMB to TOMB

Before we get into developmental psychology we need to discuss one thing

Chicken or the Egg??Chicken or the Egg??• We will try to answer one of the major themes in

psychology called the Nature vs. Nurture argumentNature vs. Nurture argument– Basically asking which is more powerful in

determining behavior and traits??

NatureNature – the idea that your behaviors, thoughts and traits come from our genetics (we are born with them) (Biology is Destiny)

NurtureNurture – the idea that our behaviors come from our environment (we learn from our surroundings)

So which one So which one is it??is it??

The Nature Argument(is sometimes compelling)

Why does Brad Pitt look the way he does?

This guy!!!

This guy will never be…

Probably genes (and I don’t Probably genes (and I don’t mean his Levi's)mean his Levi's)

Genes: Our Biological Blueprint

More on these guys later…

Another way psychologists try to answer Nature vs. Nurture is through a field called

Evolutionary PsychologyEvolutionary Psychology

Evolutionary Psychology: Explaining Universal Behaviors

• According to EP the motivator of all behavior is the passing of one's genes to the next generation for survival– (natural selection and survival of fittest)(natural selection and survival of fittest)

• There are of course real biological differences

How and why do men and women differ

sexually?

Of course, there are other differences too….

What do men and women want?(According to Evolutionary

Psychology)• Men want: • Healthy • Young • Waist 1/3 narrower

than hips.

• Women want: • Wealth • Security • Power

Behavior GeneticsBehavior Genetics

The study of the power and The study of the power and limitations of genes on who limitations of genes on who

we are.we are.

If it were possible, would you want to take a genetic test telling you which diseases you are likely to suffer from later in life?

If you or your spouse were pregnant, would you want the unborn child tested for genetic defects?

Do you think it should be legal for employers to use genetic tests in deciding whom to hire?

The Genetic RevolutionThe Genetic Revolution

TemperamentTemperament The aspects of a persons personality that we The aspects of a persons personality that we

are born with are born with whether someone is shy, aggressive, easily scaredwhether someone is shy, aggressive, easily scared They remain relatively stable over time.They remain relatively stable over time. Tends to lend evidence that nature is very powerfulTends to lend evidence that nature is very powerful

What is your temperament??

HeritabilityHeritability The degree to which genetic factors (heredity) The degree to which genetic factors (heredity)

can explain the differences of a given trait can explain the differences of a given trait among a populationamong a population

For exampleFor example A heritability estimate of 50% for intelligence A heritability estimate of 50% for intelligence

would mean what?would mean what? That genetics explains 50% of the differences That genetics explains 50% of the differences

among people in IQ scoresamong people in IQ scores

The remaining 50% of the differences would The remaining 50% of the differences would be explained by non-genetic factors, such as be explained by non-genetic factors, such as environment influencesenvironment influences

Environmental Influences on Behavior

Now On to Now On to NurtureNurture

Specific Types of Environmental Influences

Parents Prenatal Experience

Peer Influence Culture Gender

How Much Credit (or How Much Credit (or Blame ) Do Parents Blame ) Do Parents

Deserve?Deserve?Are children clay to be molded by their Are children clay to be molded by their

parents?parents?

It depends… probably not when it comes to to

personalityTake a look at your siblings…

are you alike??Parents effect your belief

systems and values much more than your personality.

Peer Influence • Perhaps the biggest

environmental influence, at least by your age may be….peerspeers

• ““Selection effect”Selection effect” – we seek out people with similar

interests– that may explain why we seem to

conform to our peers.

What can happen when there is What can happen when there is no one around to influence no one around to influence

children??children??Feral ChildrenFeral Children

• Children who have been deprived of social contact or upbringing– Literally means wild or

untamed– Suggests the important role

nurture can play in normal human development

Cultural Influences on Children

• Lev Vygotsky– Said that one’s thinking is

influenced by one’s culture– This interaction produces

a culturally specific way of thinking

– Zone of Proximal Zone of Proximal DevelopmentDevelopment• Vygotsky thought that if a

child had an older influence, they would develop faster

Nature v. Nurture

What do you think so far?

Does Nature and Nurture interact and grow off of each other?

First, how do psychologists study this question?

How do Psychologists Study How do Psychologists Study Development??Development??• Cross sectionalCross sectional

• uses people of different agesdifferent ages to compare how certain characteristics may change over the course of life

• Can be hard when the groups have grown up in different times (math tests – computers vs. calculators)

• LongitudinalLongitudinal • examines one group of participants over a long period of time• Costly, takes a long time, and typically lose participants over

time

• Biographical or retrospective studiesBiographical or retrospective studies• Looks at one person at a time through individuals memory• Good for detail, but memory may not be accurate and the

information may not be generalizable

Lets say I wanted to see at what age people are the best at playing Halo

I could go about doing this in two ways.

If I wanted to do a cross-cross-sectionalsectional study I could take ten 5 year olds, ten 10 year olds, ten 15 year olds, and ten 20 year olds, have them all play Halo and see which group lasted the longest.

This would be a fast and easy way to do the study and MOST studies are done just like this

• But, if I wanted to do a longitudinal longitudinal studystudy I would take ten 5 year olds, have them play halo, wait five years and test them again, wait five more years and test them again, then test them again at twenty and I would have my study.

• This type of research is much more rare simply because it takes so long!!!!

• So you can see that both types of research have advantages and disadvantages.

But lets get down to BusinessI am going to break developmental

psychology down into Five sections or types of development

• PhysicalPhysical – the ways our body changes from womb to tomb

• SocialSocial – the ways our social needs change from womb to

tomb• CognitiveCognitive

– the ways our thinking and learning changes from womb to tomb

• MoralMoral – the ways we think about right and wrong changes

from womb to tomb• GenderGender

– the ways we think about what our gender means from womb to tomb