CHAPTER 1Abnormal Psychology: An Overview

What is Abnormal?

Ele

men

ts o

f ab

norm

ality

in

clud

e:

Suffering

Maladaptiveness

Deviancy

Violation of the Standards of Society

Social Discomfort

Irrationality and Unpredictability

Dangerousness

What is Abnormal: key concepts

• Statistical deviance from the norm

• Impairment of functioning

• Distress

Advantages of classification• Provide nomenclature

• Permits sharing information

• Social and political implications• Classify disorders, not people

Disadvantages of classification• Stigma

• Public• Private/self-concept

• Stereotyping• Lose sight of individual differences

Culture and Abnormality• Cultural factors influence

• Presentation of disorders• Culture-specific disorders

• Example: ataque de nervios

Prevalence

Prevalence

Number of active cases in population during any given period of time

Typically expressed as percentages

Different types of prevalence estimates

Incidence

Incidence

Number of new cases in population over given period of time

Incidence figures are typically lower than prevalence figures

Research Approaches: Self-Report

Participants asked to provide information about themselves

Interviews and Questionnaires

May be inaccurate

Research Approaches: Observation

Collecting information without asking participants directly for it

Outward behavior can be observed directly

Biological variables can be observed via technologically advanced methods

Research Designs• Case study• Correlational Research• Experimental Design

Case Studies

Specific individual observed and described in detail

Subject to bias of author of case study

Low generalizability

Correlation• Relationship between two variables• Correlation coefficient

• Statistically significant?• Positive or negative?• How strong?

• Correlation does not mean causation• A→B• B→A• C→B

A

Experimental Method• Independent Variable

• Manipulated by the researcher• Typically an experimental group vs. control group

• Dependent Variable• The outcome of interest

• Random Assignment• Participants have equal chance of being in experimental group or

control• Supposed to reduce confounding variables

Single-case experiments: ABAB Design

Issues to consider

• Internal validity• How controlled?• Can we trust results of the study?

• External validity• Are the results relevant outside the study itself?

• Generalizability