Introduction to Psychology

Chapter 1: Foundations for the Study of Psychology

What is Psychology?

Psychology is the science of behavior and the mind.

BEHAVIOR refers to the observable actions of a person or animal.

MIND refers to an individual’s sensations, perceptions, memories, thoughts, dreams, motives, emotional feelings, and other subjective experiences.

SCIENCE is the attempt to answer questions through the systematic collection and logical analysis of objectively observable data.

An Historical Perspective…

Etymology

Derived from two Greek words: Psyche = the soul Logos = the study of

The Ancients

1300 BCE (Egyptian) = The brain was considered a vestigial organ

387 BCE. = Plato suggests that the brain is the mechanism of mental processes

335 BCE = Aristotle suggests that the heart is the mechanism of mental processes

An Historical Perspective…

DUALISM (pre 18th century)

The body is part of the natural world, and can be studied scientifically, while the mind exists in the supernatural and does not operate according to natural law.

René Descartes (1596-1650) Body as “complex machine” “Cogito ergo sum” PINEAL GLAND

Are there any issues with this theory?

An Historical Perspective…

MATERIALISM

Thomas Hobbes (1588-1679)

The soul is nonexistent and all behavior can be understood in terms of physical processes

Thought as a byproduct of the brain’s machinery

19th Century PHYSIOLOGY

Increased understanding of reflexes Reflexology I.M. Sechenov

Concept of localization of function in the brain E.g., Broca’s area

Behavior and mental experiences have physical causes, which can be studied scientifically.

An Historical Perspective…

EMPIRICISM (Locke, Hartley, Mill) Knowledge arises from sensory experience “tabula rasa” ASSOCIATION BY CONTIGUITY: if a person experiences two

environmental events at the same time or one right after another, those two events will become associated in the person’s mind

The way a person behaves, thinks and feels is modified, over time, by the person’s experiences is his or her environment.

An Historical Perspective…

NATIVISM (von Leibniz, Kant) Basic forms of human knowledge are innate and not

based on experience A priori: knowledge that is innate to the human mind and

is not learned A posteriori: knowledge gained from

the environment E.g. child learning a language How does all of this a priori knowledge get there in the

first place?

An Historical Perspective…

Charles Darwin (1809-1882), The Origin of Species Natural selection: Advantageous characteristics increase survival

rate and are passed down to subsequent

generations This applies to physiology AND behavior!

Darwin’s theory helps us to scientificallyunderstand the inborn universal traits that we

as human beings share (i.e. emotions, drives,

perception, learning, etc.)

Psychology recognized as a scientific discipline in 1879 when Wilhelm

Wundt opened the first university-based

psychology laboratory.

The body’s machinery, which produces behavior and mental experiences, is a product of evolution by natural selection.

Biological Causal Processes

Neural Explanations

• Study individual neurons or neural pathways

• Behavioral Neuroscience

Genetic Explanations

• Study individual differences in genes

• Behavioral Genetics

Evolutionary Explanations

• Study the development of traits in the course of evolution

• Evolutionary psychology

Environmental Causal Processes

Learning Explanations

• Study how prior experiences alter mind/behavior

• Learning psychology

Cognitive Explanations

• Study how mental information alters mind/behavior

• Cognitive psychology

Social Explanations

• Study how our mind/behavior is influenced by other people

• Social Psychology

Environmental Causal Processes

Cultural Explanations• Study how our mind/behavior is influenced

by our culture

• Cultural Psychology

Developmental Explanations• Study how our mind/behavior is influenced

by our age and development

• Developmental Psychology

Psychology as a Profession

Employment Settings

Introduction to PsychologyMethods of Psychology

Chapter 2: Methods of Psychology

Facts, Theories and Hypotheses

• FACT: is an objective statement, usually based on observation, that reasonable observers agree is true.

• THEORY: is a belief or set of interrelated beliefs that one has about some aspect of the universe, which is used to explain observed facts and to predict new ones.

• HYPOTHESIS: is a specific prediction about what will be observed in a research study, usually derived from a more general conception or theory.

• FACTS THEORIES HYPOTHESES (tested experimentally: The Scientific Method) NEW FACTS NEW THEORIES…

Further Lessons… Do you believe organisms

possess psychic abilities?

Has Paul been tested under controlled conditions?

How might our expectations influence Paul’s behavior?

Research Strategies

Research Design

• Experiments• Correlational

studies• Descriptive

studies

Setting

• Field• Laboratory

Data-collection method

• Self-report• Observation

Research Designs: Experiments• EXPERIMENT: method for testing hypotheses about

cause-effect relationships which the researcher manipulates one variable in order to assess its affect on another variable. (Assumption: Determinism).

• INDEPENDENT VARIABLE: the condition that the researcher varies in order to assess its affect upon some other variable

• DEPENDENT VARIABLE: the variable that is believed to be dependent upon (or affected by) another variable (the independent variable).

• E.g. Drug study

Experimental Subtypes

Within-Subjects One subject is tested

under varying conditions (e.g. Clever Hans)

A group of subjects are tested in each condition of the IV

Between-Subjects Manipulations of the IV

(e.g. different dosage levels) are applied to different groups of subjects

Random assignment

Effect of Treatment Condition on Depression

Research Designs: Correlational Studies

CORRELATIONAL STUDY: study which the researcher observes or measures (without manipulation) two or more variables to find relationships between them

Why not manipulate the IV? Implausible, impossible, or unethical

Correlational studies can identify relationships between variables, which allows us to make predictions about one variable based on knowledge of the other…

Correlational Studies: Limitations

CORRELATION IS NOT CAUSATION!!!

Research Designs: Descriptive Studies

DESCRIPTIVE STUDY: any study in which the researcher describes the behavior of an individual or set of individuals without systematically investigating relationships between specific variables

Research Settings

LABORATORY STUDY: any research study in which the subjects are brought to a specially designated area (laboratory) that has been set up to facilitate the researcher’s ability to control the environment or collect data.

FIELD STUDY: Any scientific research study in which data are collected in a setting other than a laboratory.

Data-Collection MethodsSelf-report methods Subjects being studied

are asked to rate or describe their own behaviors or mental states Questionnaires Interview

Observational Methods The researcher directly

observes the behavior of interest rather than relying on the subject’s self-descriptions Naturalistic Tests

Descriptive Statistics Mathematical models for summarizing sets of data.

Frequency

Percentage

Mean

Average

Median

Center Score

Standard Deviation

Variability among

your data

(X)n

(X X )2

N

Inferential Statistics

• Statistics is a game of chance!

• Level of significance

• Or p, is a probability statistic that demonstrates the level at which the observed results are due to chance.

• Statistical significance where: p ≤ .05

• p is determined by a number of factors such as sample size and amount of variability

Mathematical methods for helping researchers determine how confident they can be in drawing general conclusions (inferences) from specific sets of data.

Error vs. Bias ERROR: random

variability in research results

BIAS: nonrandom (directed) effects on research results, caused by some factor or factors extraneous to the research hypothesis

Types of Bias

• A subset of the population that is not representative of the population as wholeSampling Bias

• Reliability: yields similar results each time• Validity: measures what it’s supposed to

measure

Measurement Bias

• Bias that derives from the researcher’s desire or expectation that a subject or set of subjects will behave in a certain way

Expectancy Bias

The Facilitated-Communication Experiment

Avoiding Expectancy Effects

Observer Expectancy BLIND: those who collect

data are deliberately kept uninformed about aspect’s of the study’s design that could lead them to (un)consciously bias the results.

Subject-Expectancy BLIND

DOUBLE-BLIND EXPERIMENT

PLACEBO: an inactive substance given to subjects assigned to the nondrug group.

Ethical Issues in Psychological Research

Research with Humans

1. The person’s right to privacy

2. The possibility of discomfort or harm

3. The use of deception

• Institutional Review Board (IRB)

Respect for Persons

Beneficence Justice

Ethical Issues in Psychological Research

Research with Animals

• Animal research used to study specific animal behavior, to learn about general behavioral patterns, to test hypotheses that could not be tested on humans

• Most studies require the sacrifice of experimental animals at their conclusion