From speculation to science: The Birth of Modern Psychology

Aristotle (4th century BCE) had ideas about how the body and mind work.His method: making guesses.

Wilhelm Wundt (1832-1920) added two key elements to help make psychology a science:1. carefully measured observations2. experiments

Structuralism

Edward Titchener, like his teacher Wundt, used data from introspection, reporting on sensations and other elements of experience.

Structuralism: Using these introspective reports to build a view of the mind’s structure

Functionalism: The school of thought that Psychological processes have a function: helping us survive as individuals, adapt as a species

The developer of functionalism, William James (1842-1910), asked: How did the human style of thinking and behavior enable our ancestors to live long enough to reproduce?

James mentored another pioneer

William James

Shifting definitions of “psychology”

Wilhelm Wundt and

Edward Titchener,

around 1900: “The science

of mental life.”

John B. Watson and B.F. Skinner,

behaviorists, 1920’s: “The

scientific study of

observable behavior.”

Cognitive psychologists,

1960’s, studied

internal mental processes, helped by

neuroscience.

Now we combine these definitions: “The science of behavior and mental

processes.”

Behaviorists study and experiment with observable behavior.

Watson experimented with conditioned responses.

Skinner studied the way consequences shape behavior.

Like other behaviorists, he saw little value in introspection.

Trends in Psychological Science: Behaviorism

John B. Watson

B. F. Skinner

Sigmund Freud, founder of psychoanalysis: He studied and helped people with a

variety of mental disorders. More about Freud when we study

personality and therapy

Sigmund Freud

Trends in Psychology: Freudian/Psychoanalytic Psychology

Humanists: Abraham Maslow and Carl Rogers (1960s): studied people who were thriving rather

than those who had psychological problems.

developed theories and treatments to help people to feel accepted and to reach their full potential.

Carl Rogers

Abraham Maslow

Trends in Psychology: Humanism

© 2012 John Wiley & Sons, Inc. All rights reserved.

Cognitive perspective

Social-cultural

Behavioral genetics

Neuroscience

Psychodynamic

Behaviorist

Evolutionary

There are many perspectives for

describing psychological phenomena: From different angles, you ask different questions:

How reliable is memory? How can we improve our thinking?

Could our behavior, skills, and attitudes be “downloads” from our culture?

Could our behavior, skills, and attitudes be genetically programmed instincts?What role do our bodies and brains play in emotions? How is pain inhibited? Can we trust our senses?

Do inner childhood conflicts still plague me and affect my behavior?How are our problematic behaviors reinforced? How do our fears become conditioned? What can we do to change these fears and behaviors?Why are humans prone to panic, anger, and making irrational judgments?

The Big Issue in Psychology: N-N

To what extent are our traits already set in place at birth (our “Nature”)?

And to what extent do our traits develop in response to our environment/ experience (our “Nurture”)?

The Nature-Nurture Question:

vs. Nature Nurtur

e

Plato: Ideas such

as “the good” and “beauty”

are inborn. Descartes:

Some ideas are innate.

Charles Darwin: Some traits become part of our nature through

natural selection: they help us survive long

enough to pass the traits to the next generation.

Aristotle:All knowledge

comes through the senses.

John Locke:The mind is a

blank slate (blank chalkboard or

screen) “written on” by experience.

Nature Nurture

We have differences

that are shaped by our environment.

We share a common

origin that gives us an

inborn human nature in common.

+

“Nurture works on what Nature endows.”

The Roles of Nature and

Nurture:

Biology Plus Environment..are part of

psychology’s three “biopsychosocial” levels of analysis.

The deep level, Biology:

genes, brain, neuro-

transmitters, survival, reflexes,

sensation

The outer level, Environment:

social Influences, culture,

education, relationshipsIn the middle,

Psychology: thoughts, emotions,

moods, choices, behaviors, traits,

motivations, knowledge, perceptions

Biopsychosocial Model

This unifying and integrative model views biological processespsychological factors and social forces as interrelated influences that interact with the seven major perspectives

© 2012 John Wiley & Sons, Inc. All rights reserved.

When our natural thinking style fails:

Hindsight bias:“I knew it all

along.”

Overconfidence error:

“I am sure I am correct.”

The coincidence error, ormistakenly perceiving

order in random events: “The dice must be fixed

because you rolled three sixes in a row.”

© 2012 John Wiley & Sons, Inc. All rights reserved.

Six Steps of the

Scientific Method Cycle

Important Terms!

HypothesisSpecific, testable prediction about how one factor, or variable, is related to another Operational DefinitionPrecise description of how the variables in a study will be observed and measured (for example, drug abuse might be operationally defined as “the number of missed work days due to excessive use of an addictive substance”)Statistical Significance Statistical statement of how likely it is that a study’s result occurred merely by chance

© 2012 John Wiley & Sons, Inc. All rights reserved.

Research goal and strategy: Description

Strategies for gathering this information: Case Study: observing

and gathering information to compile an in-depth study of one individual

Naturalistic Observation: gathering data about behavior; watching but not intervening

Surveys and Interviews: having other people report on their own attitudes and behavior

Descriptive research is a systematic, objective

observation of people.

The goal is to provide a

clear, accurate picture of people’s

behaviors, thoughts, and

attributes.

Case Study

Examining one individual in depthBenefit: can be a source of ideas about human nature in generalExample: cases of brain damage have suggested the function of different parts of the brain (e.g. Phineas Gage seen here)Danger: overgeneralization from one example; “Joe got better after tapping his foot, so tapping must be the key to health!”

Observing “natural” behavior means just watching (and taking notes), and not trying to change anything.

This method can be used to study more than one individual, and to find truths that apply to a broader population.

Naturalistic Observation

The Survey Definition: A method of

gathering information about many people’s thoughts or behaviors through self-report rather than observation.

Keys to getting useful information: Be careful about the

wording of questions Only question randomly

sampled people

Wording effectsthe results you get from a survey can be changed by your word selection.

Example:

Q: Do you have motivation to study hard for this course?

Q: Do you feel a desire to study hard for this course?

What psychology science mistake was made here?

Hint #1: Harry Truman won.

Hint #2: The Chicago Tribune interviewed people about whom they would vote for.

Hint #3: in 1948.

Hint #4: by phone.

Random Sampling• If you want to find out

something about men, you can’t interview every single man on earth.

• Sampling saves time. You can find the ratio of colors in this jar by making sure they are well mixed (randomized) and then taking a sample.

population sample

Random sampling is a technique for making

sure that every individual in a population has an

equal chance of being in your sample.

“Random” means that your selection of participants is driven only by chance, not by any characteristic.

CorrelationGeneral Definition: an observation that two traits or attributes are related to each other (thus, they are “co”-related) Scientific definition: a measure of how closely two factors vary together, or how well you can predict a change in one from observing a change in the other

In a case study: The fewer hours the boy was allowed to sleep, the more episodes of

aggression he displayed.

A possible result of many descriptive studies:discovering a correlation

In a naturalistic observation: Children in a

classroom who were dressed in heavier clothes

were more likely to fall asleep than those wearing

lighter clothes.

In a survey: The greater the number of Facebook friends,

the less time was spent studying.

Correlation Coefficient• The correlation coefficient is a number representing how closely

and in what way two variables correlate (change together).• The direction of the correlation can be positive (direct relationship;

both variables increase together) or negative (inverse relationship: as one increases, the other decreases).

• The strength of the relationship, how tightly, predictably they vary together, is measured in a number that varies from 0.00 to +/- 1.00.

Close to +1.0

(strong negative correlation)

(no relationship,no correlation)

Guess the Correlation Coefficients

(strong positive correlation)

Height vs. shoe size Years in school vs. years in jail

Height vs. intelligence

Close to 0.0

Close to -1.0

If we find a correlation, what conclusions can

we draw from it?

Let’s say we find the following result: there is a positive correlation between two variables, ice cream sales, and rates of violent crime How do we explain this?

Correlation is not Causation!

“People who floss more regularly have less risk of heart disease.”

“People with bigger feet tend to be taller.”

If this data is from a survey, can we conclude that flossing might prevent heart disease? Or that people with heart-healthy habits also floss regularly?

Does that mean having bigger feet causes height?

If self-esteem correlates with depression,there are still numerous possible causal links:

So how do we find out about causation? By experimentation

Testing the theory that ADHD = sugar: removing sugar from the diet of children with ADHD to see if it makes a difference

The depression/self-esteem example: trying interventions that improve self-esteem to see if they cause a reduction in depression

Experimentation: manipulating one factor in a

situation to determine its

effect

The Control Group• If we manipulate a variable in an experimental group

of people, and then we see an effect, how do we know the change wouldn’t have happened anyway?

• We solve this problem by comparing this group to a control group, a group that is the same in every way except the one variable we are changing.

Example: two groups of children have ADHD, but only one group stops eating refined sugar.

By using random assignment: randomly

selecting some study participants to be assigned to the control group or the

experimental group.

How do make sure the control group is really identical in every way to the experimental group?

To clarify two similar-sounding terms…

First you sample, then you sort

(assign)

Random assignment of participants to

control or experimental groups is how you control all

variables except the one you’re manipulating.

Random sampling is how you get a pool of

research participants that represents the

population you’re trying to

learn about.

Placebo effect

Placebo effect: experimental effects that are caused by expectations about

the intervention

How do we make sure that the experimental group doesn’t experience an effect because they expect to experience it?

How can we make sure both groups expect to get better, but only one gets the real intervention being studied?

Working with the placebo effect:Control groups may be given a placebo – an inactive substance or other fake treatment in place of the experimental treatment. The control group is ideally “blind” to whether they are getting real or fake treatment.Many studies are double-blind – neither participants nor research staff knows which participants are in the experimental or control groups.

The variable we are able to manipulate independently of what the other variables are doing is called the independent variable (IV).

• If we test the ADHD/sugar hypothesis: • Sugar = Cause = Independent Variable• ADHD = Effect = Dependent Variable

The variable we expect to experience a change which depends on the manipulation we’re doing is called the dependent variable (DV).

• Did more hyper kids get to choose to be in the sugar group? Then their preference for sugar would be a confounding variable. (preventing this problem: random assignment).

The other variables that might have an effect on the dependent variable are confounding variables.

Naming the variables

An experiment is a type of research in which the researcher carefully

manipulates a limited number of factors (IVs) and measures the impact on other factors

(DVs).*in psychology, you would be looking at

the effect of the experimental change (IV) on a behavior or mental process (DV).

Filling in our definition of experimentation