Psychological Science

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• Chapter 1
• Psychological Science

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What is Psychology?

• the science of behavior and mental
  processes

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Psychologys Current Perspectives
Perspective Focus
Neuroscience How the body and brain create
emotions, memories, and sensory experiences
Evolutionary How nature selects traits that
promote the perpetuation of ones genes
Behavior How much our genes, and our
environment, influence our genetics individual
differences
Psychodynamic How behavior springs from
unconscious drives and conflicts
Behavioral How behavior is learned
Cognitive How we encode, process, store, and
retrieve information
Social-cultural How behavior and thinking vary
across situations and cultures
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Current Perspectives

• Perspective Focus
• Neuroscience How the brain creates
  emotions, thoughts, and behaviors
• Evolutionary How nature selects traits
• that promote survival of
• our genes

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Current Perspectives

• Perspective Focus
• Behavior Genetics How much our genes
• are responsible for
• individual differences
• Psychodynamic How behavior springs
• from unconscious drives
• and conflicts

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Current Perspectives

• Perspective Focus
• Behavioral How we learn observable
• behavior
• Cognitive How we encode, process,
• store and retrieve
• information

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Current Perspectives

• Perspective Focus
• Social-cultural How social situations and
  culture influences behavior and thought
• Eclectic Drawing from two or more of the
  perspectives to explain behavior or
  thought processes

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Psychology vs. Psychiatry

• Clinical Psychology (Ph.D)
• a specialty in psychology
• clinical psychologists
• uses psychotherapy to treat psychological
  disorders
• Psychiatry (M.D.)
• a specialty in medicine
• psychiatrists
• may prescribe medication and use psychotherapy

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The Scientific Method
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Scientific Method

• Goal is good theory
• theories explain behavior
• Science guards against
• faulty explanations
• hindsight bias

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Faulty Explanations Intuition and
The Hot Streak
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Hindsight Bias

• tendency to believe, after learning an outcome,
  that one would have foreseen it
• the I-knew-it-all-along phenomenon

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The Scientific Method

• Theory
• a general explanation as to why a behavior occurs
• Hypothesis
• a testable prediction
• often derived from a theory
• Example I predict A will cause B

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The Scientific Method
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The Scientific Method

• Operational Definition
• a statement of the procedures (operations) used
  to define research variables
• for example, intelligence may be operationally
  defined as what an intelligence test measures

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The Scientific Method

• Replication
• repeating the procedures of a research study with
  another sample of participants
• to see whether the results are also repeated

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Types of Scientific Methods

• 1. Case Study
• 2. Survey
• 3. Naturalistic Observation
• 4. Correlation Coefficient
• 5. Experiment

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Types of Scientific Methods

• 1. Case Study
• in depth observation of one person in hopes of
  revealing universal laws

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Types of Scientific Methods

• 2. Survey
• a questionnaire about attitudes or behavior given
  to a sample of people

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A Key Distinction Population versus Sample

• Population
• a specific group of interest to the researcher
  (e.g., all children!)
• a sample is drawn from a population

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Drawing a Sample

• Male subjects, neurosis, and sex!

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Good Samples

• Representative Sample
• a sample that is a perfect reflection of a
  population, only smaller in size
• Random Sample
• a sample that fairly represents a population
  because each member of the sample had an equal
  chance of being chosen

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Types of Scientific Methods

• 3. Naturalistic Observation
• observing and recording behavior in naturally
  occurring situations, trying not to manipulate
  the situation

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Types of Scientific Methods

• 4. Correlation Coefficient
• a measure that shows the extent to which two
  variables change together
• good for prediction
• Note correlation does not imply causation!

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Correlation and Causation

• Three possible cause-effect relations

could cause
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Types of Scientific Methods

• 5. Experiment
• a procedure for identifying the causes of
  behavior
• all experiments have two variables
• Independent Variable variable manipulated by a
  researcher
• Dependent Variable observed consequence of IV on
  some behavior or mental process

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The Dependent Variable

• Dependent Variable
• the variable that is being measured
• value of DV depends on value of IV

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Experiment

• Experimental Group
• these participants are exposed to the independent
  variable (treatment)
• Control Group
• these participants do not receive the independent
  variable
• is a comparison group we use to be able to see
  the effect of the independent variable
  (treatment)
• Note the measure (DV) is taken for both groups

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Experiment

• Random Assignment
• assigning participants to experimental and
  control groups by chance
• minimizes preexisting differences between those
  assigned to the different groups

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Experiment

• Placebo
• an inert substance (e.g., sugar pill) instead of
  an active agent (e.g., drug)
• placebo is administered to see if it triggers the
  same reaction as the active agent (IV)
• Placebo Effect
• any effect on behavior caused by a placebo

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Experiment

• Single-blind Procedure
• Research participants dont know if they are
  getting the placebo or active agent.
• Double-blind Procedure
• Participants dont know .
• Also, research staff doesnt know (blind) who is
  getting the active agent vs. placebo

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The Scientific Method
Comparing Research Methods
Research Method Basic Purpose
How Conducted What is
Manipulated
Descriptive To observe and
Case studies, surveys, Nothing (Goal
Describe) record behavior and
naturalistic observations
Correlational To detect naturally
Computing statistical Nothing (Goal Predict)
occurring relationships association,
sometimes to assess how well among
survey one variable predicts responses
Experimental To explore cause Manipulating
one or Independent (Goal Explain) and
effect more IVs and using variable(s) random
assignment to eliminate preexisting dif
ferences among subjects
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Practice Hypothesis Testing

• Drug A makes children more attentive in school
• The larger the family, the duller the children
• Cigarette smoking causes lung cancer
• Television violence is related to aggression in
  children
• Absence makes the heart grow fonder