lOMoARcPSD|9308590
Chapter 1 — Introduction to Psychology
What is Psychology? Science vs Intuition
• Psychology is the scientific study of the mind, brain and behavior
• Psychology spans multiple levels of analysis: molecular ➔ w ➔ neurological/physiological ➔
mental ➔ behavioral ➔ social
Five especially intriguing challenges:
• All actions are multiply determined: produced by many factors. This makes behavior difficult to
predict.
• Psychological influences are rarely independent of each other: factors are interrelated.
• individual differences between people cause variations among people’s thinking, emotion,
personality and behavior.
• Reciprocal determinism—the fact that we mutually influence each other’s behavior.
• People’s behavior is often also shaped by culture.
• We trust our common sense because we’re prone to naive realism: seeing the world precisely
as it is. “seeing is believing” ➔ “believing is seeing”.
• We must learn when—and when not—to trust our common sense.
Science is an approach to evidence that begins with empiricism.
• A scientific theory is an explanation for a large number of findings in the natural world.
• A testable prediction is a hypothesis.
• Theories are general explanations, hypotheses are predictions derived from them.
Most crucial traps in science:
• Confirmation bias: tendency to seek out evidence that supports our beliefs and deny, dismiss
or distort evidence that contradicts them.
• Belief perseverance: the tendency to stick to our initial beliefs even when evidence contradicts
them.
metaphysical claims are assertions about the world that we can’t test with scientific evidence.
Psychological Pseudoscience: Imposters of Science
• Pseudoscience is a set of claims that seems scientific but isn’t.
Crucial warning signs:
• Overuse of ad hoc immunizing hypothesis (escape hatch or loophole that defenders of a
theory use to protect their theory from falsification)
• Lack of self-correction: pseudoscientific claims are rarely updated in light of new data.
• Over-reliance on anecdotes: anecdotes are difficult to verify and difficult to interpret as
evidence.
• Patternicity: tendency to detect meaningful patterns in random stimuli. Our adaptive
tendencies can lead us astray and perceive patterns even when they’re not there.
• Terror management theory: theory proposing that our awareness of death leaves us with an
underlying sense of terror with which we cope by adapting reassuring cultural worldviews.
• Three important logical fallacies to bear in mind to separate science from pseudoscience:
• Emotional reasoning fallacy: using our emotions as guides for evaluating the validity of a claim.
• Bandwagon fallacy: assuming a claim is right only because many people believe it.
• Not me fallacy: believing that we’re immune from errors in thinking that afflict other people.
, lOMoARcPSD|9308590
Three major reasons we should be concerned about pseudoscience:
• Opportunity cost: what we give up
Even treatments that are harmless can cause harm indirectly by causing people to forfeit
the chance to obtain a treatment that works.
• Direct harm
Pseudoscientific treatments can do dreadful harm to those who receive them.
• An inability to think scientifically as citizens
We need to apply scientific thinking skills to all aspects of our lives.
Scientific Thinking: Distinguishing Fact from Fiction
• Scientific skepticism evaluates all claims with an open mind but insists on persuasive
evidence before accepting them.
• Critical thinking is a set of skills for evaluating all claims in an open-minded and careful fashion
(scientific thinking).
The Six Principles of Scientific Thinking:
1. Ruling Out Rival Hypotheses
Have important alternative explanations for the findings been excluded?
2. Correlation Isn’t Causation
Can we be sure that A causes B?
• correlation-causation fallacy: error of assuming that because one thing is associated with the
other, it must cause the other
• variable: anything that can vary
3. Falsifiability
Can the claim be disproved?
falsifiable: capable of being disproved
4. Replicability
Can the results be duplicated in other studies?
• replicability: when a study’s finding are able to be duplicated, ideally by independent
investigators
• decline effect: fact that the size of certain psychological findings appears to be shrinking over
time
5. Extraordinary Claims Require Extraordinary Evidence
Is the evidence as strong as the claim?
6. Occam’s Razor
Does a simpler explanation fit the data just as well?
Psychology’s Past and Present: A Long, Strange Trip
Early History
• For many centuries, Psychology was difficult to distinguish from Philosophy (only
contemplation, no experiments).
• Wilhelm Wundt (1832-1920) developed the first psychological laboratory in Leipzig (1879).
• Wundt pioneered a technique called introspection: a method by which trained observers
carefully reflect and report on their mental experiences.
Theoretical Frameworks of Psychology
• Structuralism (the elements of the mind):
School of psychology that aimed to identify the basic elements of psychological experience.
They assumed that the imperfect method introspection could provide enough information for a
complete science of psychology. Leading figure: founder Edward Bradford Titchener (1867-1927), a
student of Wundt.
, lOMoARcPSD|9308590
• Functionalism (psychology meets Darwin):
School of psychology that aimed to understand the adaptive purposes of psychological
characteristics. Was substantially influenced by Darwin’s theory of natural selection: the
principle that organisms that possess adaptions survive and reproduce at a higher rate than do
other organisms. Leading figures: founder William James, influenced by Charles Darwin (1809-1882).
• Behaviorism (the laws of learning):
School of psychology that focuses on uncovering the general laws of learning by looking at
observable behavior, the “only proper” subject matter of psychology. No need to peer “inside”
the organism: we can comprehend behavior exclusively by looking outside the organism. The
human mind as a black box (input ➔ output). Leading figures: Ivan Pavlov, John B. Watson, B. F.
Skinner.
• Cognitivism (opening the black box):
Cognitive psychology is a school of psychology that proposes that thinking is central to
understanding behavior. It examines the role of mental processes on behavior. Leading figures:
Jean Piaget, Ulric Neissier. Cognitive neuroscience is a relatively new field of psychology that
examines the relation between brain functioning and thinking.
• Psychoanalysis (the depths of the unconscious): School of psychology, founded by
Sigmund Freud (1856-1939), that focuses on internal psychological processes (impulses,
thoughts, memories) of which we’re unaware. According to psychoanalysts, the primary
influences on behavior are not outside forces (rewards/punishments) but unconscious drives
(sexuality/aggression).
The Multifaceted World of Psychology
The field of psychology is remarkably diverse (see Table 1.6, page 63):
• Clinical psychologist
• Counseling psychologist
• School psychologist
• Developmental psychologist
• Experimental psychologist
• Biological psychologist
• Forensic psychologist
• Industrial-organizational psychologist
Great debates of psychology
• The nature-nurture debate: are our behavior attributable mostly to our genes (nature) or to our
rearing environments (nurture)?
‣ John Locke (1632-1704): tabula rasa (blank slate).
‣ Behavior geneticists show that a lot of traits are also attributable to our genes.
‣ Evolutionary psychology is a discipline which applies Darwin’s theory to human and animal
behavior.
• The free will-determinism debate: to what extent are our behaviors freely selected rather than
caused by factors outside our control?
‣ Some argue that we all possess free will.
‣ Others maintain that is is an illusion.
How psychology affects our lives
• Basic research examines how the mind works
• Applied research examines how we can use basic research to solve real-world problems.
Insist on evidence.
, lOMoARcPSD|9308590
Chapter 2 —Research Methods in Psychology
The Beauty and Necessity of Good Research Design
• Research design matters
• The prefrontal lobotomy was a surgical procedure that servers fibers connecting the frontal
lobes of the brain from the underlying thalamus. The scientific world assumed that clinical
observations (“I can see that it works”) were sufficient evidence for this treatment’s effectiveness
for schizophrenia. It was later found to be useless and its believers had been deceived by naive
realism and confirmation bias.
• Two modes of thinking:
‣ System 1 thinking, or “intuitive thinking”: our brains are largely on autopilot.
heuristic: mental shortcut or rule of thumb that helps us to streamline our thinking and
make sense of the world.
‣ System 2 thinking, or “analytical thinking”: in contrast, this is slow and reflective. Used to
override intuitive thinking. Good research designs can help us harness the power of analytical
thinking.
The Scientific Method: Toolbox of Skills
• Naturalistic observation: watching behavior in real-world settings without trying to
manipulate the situation.
‣ High in external validity: the extent to which we can generalize findings to a real-world
setting.
‣ Low in internal validity: the extent to which we can draw cause-and-effect inferences from a
study.
• Case study: research design that examines one person or a small number of people in depth,
often over an extended time period.
‣ Helpful in providing existence proof: demonstrations that a given psychological phenomenon
can occur
• Random selection: procedure that ensures every person in a population has an equal chance
of being chosen to participate, to guarantee the most accurate results over sample populations.
• Reliability: consistency of measurement (a reliable questionnaire, for example, yields similar
scores over time)
• Interrater reliability: the extent to which different people who conduct an interview or make
behavioral observations agree on the characteristics they’re measuring.
• Validity: the extent to which a measure assesses what it purports (claims) to measure.
• Self-report measures of personality traits:
‣ Can work reasonably well, but…
‣ Assume that respondents possess enough insight into their personality characteristics.
‣ Typically assume that participants are honest in their responses: some respondents engage in
response sets: tendencies to distort their answers to questionnaire items, often in a way that
paints them in a positive light.
‣ An opposite response set is malingering: the tendency to make ourselves appear
psychologically disturbed with the aim of achieving a clear-cut personality goal.
• Rating data (others rating someone):
‣ The halo (horn’s) effect: the tendency of ratings of one positive characters to “spill over” to
influence the ratings of other positive characteristics.
• Correlational design: research design that examines the extent to which two variables are
associated (co-relate).
‣ Correlational designs allow us to generate predictions about the future.
Chapter 1 — Introduction to Psychology
What is Psychology? Science vs Intuition
• Psychology is the scientific study of the mind, brain and behavior
• Psychology spans multiple levels of analysis: molecular ➔ w ➔ neurological/physiological ➔
mental ➔ behavioral ➔ social
Five especially intriguing challenges:
• All actions are multiply determined: produced by many factors. This makes behavior difficult to
predict.
• Psychological influences are rarely independent of each other: factors are interrelated.
• individual differences between people cause variations among people’s thinking, emotion,
personality and behavior.
• Reciprocal determinism—the fact that we mutually influence each other’s behavior.
• People’s behavior is often also shaped by culture.
• We trust our common sense because we’re prone to naive realism: seeing the world precisely
as it is. “seeing is believing” ➔ “believing is seeing”.
• We must learn when—and when not—to trust our common sense.
Science is an approach to evidence that begins with empiricism.
• A scientific theory is an explanation for a large number of findings in the natural world.
• A testable prediction is a hypothesis.
• Theories are general explanations, hypotheses are predictions derived from them.
Most crucial traps in science:
• Confirmation bias: tendency to seek out evidence that supports our beliefs and deny, dismiss
or distort evidence that contradicts them.
• Belief perseverance: the tendency to stick to our initial beliefs even when evidence contradicts
them.
metaphysical claims are assertions about the world that we can’t test with scientific evidence.
Psychological Pseudoscience: Imposters of Science
• Pseudoscience is a set of claims that seems scientific but isn’t.
Crucial warning signs:
• Overuse of ad hoc immunizing hypothesis (escape hatch or loophole that defenders of a
theory use to protect their theory from falsification)
• Lack of self-correction: pseudoscientific claims are rarely updated in light of new data.
• Over-reliance on anecdotes: anecdotes are difficult to verify and difficult to interpret as
evidence.
• Patternicity: tendency to detect meaningful patterns in random stimuli. Our adaptive
tendencies can lead us astray and perceive patterns even when they’re not there.
• Terror management theory: theory proposing that our awareness of death leaves us with an
underlying sense of terror with which we cope by adapting reassuring cultural worldviews.
• Three important logical fallacies to bear in mind to separate science from pseudoscience:
• Emotional reasoning fallacy: using our emotions as guides for evaluating the validity of a claim.
• Bandwagon fallacy: assuming a claim is right only because many people believe it.
• Not me fallacy: believing that we’re immune from errors in thinking that afflict other people.
, lOMoARcPSD|9308590
Three major reasons we should be concerned about pseudoscience:
• Opportunity cost: what we give up
Even treatments that are harmless can cause harm indirectly by causing people to forfeit
the chance to obtain a treatment that works.
• Direct harm
Pseudoscientific treatments can do dreadful harm to those who receive them.
• An inability to think scientifically as citizens
We need to apply scientific thinking skills to all aspects of our lives.
Scientific Thinking: Distinguishing Fact from Fiction
• Scientific skepticism evaluates all claims with an open mind but insists on persuasive
evidence before accepting them.
• Critical thinking is a set of skills for evaluating all claims in an open-minded and careful fashion
(scientific thinking).
The Six Principles of Scientific Thinking:
1. Ruling Out Rival Hypotheses
Have important alternative explanations for the findings been excluded?
2. Correlation Isn’t Causation
Can we be sure that A causes B?
• correlation-causation fallacy: error of assuming that because one thing is associated with the
other, it must cause the other
• variable: anything that can vary
3. Falsifiability
Can the claim be disproved?
falsifiable: capable of being disproved
4. Replicability
Can the results be duplicated in other studies?
• replicability: when a study’s finding are able to be duplicated, ideally by independent
investigators
• decline effect: fact that the size of certain psychological findings appears to be shrinking over
time
5. Extraordinary Claims Require Extraordinary Evidence
Is the evidence as strong as the claim?
6. Occam’s Razor
Does a simpler explanation fit the data just as well?
Psychology’s Past and Present: A Long, Strange Trip
Early History
• For many centuries, Psychology was difficult to distinguish from Philosophy (only
contemplation, no experiments).
• Wilhelm Wundt (1832-1920) developed the first psychological laboratory in Leipzig (1879).
• Wundt pioneered a technique called introspection: a method by which trained observers
carefully reflect and report on their mental experiences.
Theoretical Frameworks of Psychology
• Structuralism (the elements of the mind):
School of psychology that aimed to identify the basic elements of psychological experience.
They assumed that the imperfect method introspection could provide enough information for a
complete science of psychology. Leading figure: founder Edward Bradford Titchener (1867-1927), a
student of Wundt.
, lOMoARcPSD|9308590
• Functionalism (psychology meets Darwin):
School of psychology that aimed to understand the adaptive purposes of psychological
characteristics. Was substantially influenced by Darwin’s theory of natural selection: the
principle that organisms that possess adaptions survive and reproduce at a higher rate than do
other organisms. Leading figures: founder William James, influenced by Charles Darwin (1809-1882).
• Behaviorism (the laws of learning):
School of psychology that focuses on uncovering the general laws of learning by looking at
observable behavior, the “only proper” subject matter of psychology. No need to peer “inside”
the organism: we can comprehend behavior exclusively by looking outside the organism. The
human mind as a black box (input ➔ output). Leading figures: Ivan Pavlov, John B. Watson, B. F.
Skinner.
• Cognitivism (opening the black box):
Cognitive psychology is a school of psychology that proposes that thinking is central to
understanding behavior. It examines the role of mental processes on behavior. Leading figures:
Jean Piaget, Ulric Neissier. Cognitive neuroscience is a relatively new field of psychology that
examines the relation between brain functioning and thinking.
• Psychoanalysis (the depths of the unconscious): School of psychology, founded by
Sigmund Freud (1856-1939), that focuses on internal psychological processes (impulses,
thoughts, memories) of which we’re unaware. According to psychoanalysts, the primary
influences on behavior are not outside forces (rewards/punishments) but unconscious drives
(sexuality/aggression).
The Multifaceted World of Psychology
The field of psychology is remarkably diverse (see Table 1.6, page 63):
• Clinical psychologist
• Counseling psychologist
• School psychologist
• Developmental psychologist
• Experimental psychologist
• Biological psychologist
• Forensic psychologist
• Industrial-organizational psychologist
Great debates of psychology
• The nature-nurture debate: are our behavior attributable mostly to our genes (nature) or to our
rearing environments (nurture)?
‣ John Locke (1632-1704): tabula rasa (blank slate).
‣ Behavior geneticists show that a lot of traits are also attributable to our genes.
‣ Evolutionary psychology is a discipline which applies Darwin’s theory to human and animal
behavior.
• The free will-determinism debate: to what extent are our behaviors freely selected rather than
caused by factors outside our control?
‣ Some argue that we all possess free will.
‣ Others maintain that is is an illusion.
How psychology affects our lives
• Basic research examines how the mind works
• Applied research examines how we can use basic research to solve real-world problems.
Insist on evidence.
, lOMoARcPSD|9308590
Chapter 2 —Research Methods in Psychology
The Beauty and Necessity of Good Research Design
• Research design matters
• The prefrontal lobotomy was a surgical procedure that servers fibers connecting the frontal
lobes of the brain from the underlying thalamus. The scientific world assumed that clinical
observations (“I can see that it works”) were sufficient evidence for this treatment’s effectiveness
for schizophrenia. It was later found to be useless and its believers had been deceived by naive
realism and confirmation bias.
• Two modes of thinking:
‣ System 1 thinking, or “intuitive thinking”: our brains are largely on autopilot.
heuristic: mental shortcut or rule of thumb that helps us to streamline our thinking and
make sense of the world.
‣ System 2 thinking, or “analytical thinking”: in contrast, this is slow and reflective. Used to
override intuitive thinking. Good research designs can help us harness the power of analytical
thinking.
The Scientific Method: Toolbox of Skills
• Naturalistic observation: watching behavior in real-world settings without trying to
manipulate the situation.
‣ High in external validity: the extent to which we can generalize findings to a real-world
setting.
‣ Low in internal validity: the extent to which we can draw cause-and-effect inferences from a
study.
• Case study: research design that examines one person or a small number of people in depth,
often over an extended time period.
‣ Helpful in providing existence proof: demonstrations that a given psychological phenomenon
can occur
• Random selection: procedure that ensures every person in a population has an equal chance
of being chosen to participate, to guarantee the most accurate results over sample populations.
• Reliability: consistency of measurement (a reliable questionnaire, for example, yields similar
scores over time)
• Interrater reliability: the extent to which different people who conduct an interview or make
behavioral observations agree on the characteristics they’re measuring.
• Validity: the extent to which a measure assesses what it purports (claims) to measure.
• Self-report measures of personality traits:
‣ Can work reasonably well, but…
‣ Assume that respondents possess enough insight into their personality characteristics.
‣ Typically assume that participants are honest in their responses: some respondents engage in
response sets: tendencies to distort their answers to questionnaire items, often in a way that
paints them in a positive light.
‣ An opposite response set is malingering: the tendency to make ourselves appear
psychologically disturbed with the aim of achieving a clear-cut personality goal.
• Rating data (others rating someone):
‣ The halo (horn’s) effect: the tendency of ratings of one positive characters to “spill over” to
influence the ratings of other positive characteristics.
• Correlational design: research design that examines the extent to which two variables are
associated (co-relate).
‣ Correlational designs allow us to generate predictions about the future.
