What Is Abnormal Psychology?
How Do We Define Abnormal Behavior?
Various criteria are used to define abnormal behavior. Psychologists generally consider behavior
abnormal when it meets some combination of the following criteria: (1) unusual or infrequent;
(2) socially unacceptable or in violation of social norms; (3) fraught with misperceptions or
misinterpretations of reality; (4) associated with states of severe personal distress; (5)
maladaptive or self-defeating; (6) and dangerous.
The determination of which behavior patterns are deemed abnormal depends on cultural beliefs
and expectations. Concepts of health and illness may also have different meanings in different
cultures. Abnormal behavior patterns may take different forms in different cultures, and societal
views of abnormal behavior vary across cultures.
Historical Perspectives on Abnormal Behavior
Ancient societies attributed abnormal behavior to divine or supernatural forces. In medieval
times, belief in possession held sway, and exorcists were used to rid people who behaved
abnormally of the evil spirits that were believed to possess them. There were some authorities in
ancient times, such as the Greek physicians Hippocrates and Galen, who believed that abnormal
behavior reflected natural causes. The nineteenth century German physician Wilhelm Griesinger
argued that abnormal behavior was caused by diseases of the brain. Along with Emil Kraeplin,
another German physician who followed him, Griesinger was influential in the development of
the modern medical model, which likens abnormal behavior patterns to physical illnesses.
Asylums, or "madhouses," began to crop up throughout Europe in the late fifteenth and early
sixteenth centuries, often on the site of former leprosariums. Conditions in these asylums were
dreadful and in some, such as the Bethlehem Hospital in England, a circus atmosphere prevailed.
With the rise of moral therapy in the nineteenth century, largely spearheaded by the Frenchmen
Jean-Baptiste Pussin and Phillipe Pinel, conditions in mental hospitals improved.
Proponents of moral therapy believed that mental patients could be restored to functioning if they
were treated with dignity and understanding. The decline of moral therapy in the latter part of the
nineteenth century led to a period of apathy and to the belief that the "insane" could not be
successfully treated. Conditions in mental hospitals deteriorated, and the hospitals offered little
more than custodial care.
In the middle of the twentieth century, public outrage and concern about the plight of mental
patients mobilized legislative efforts toward the development of community mental health
centers as alternatives to long-term hospitalization. This movement toward deinstitutionalization
was spurred by the introduction of psychoactive drugs called phenothiazines, which curbed the
more flagrant features of schizophrenia.
Research Methods in Abnormal Psychology
The scientific approach focuses on four general objectives: description, explanation, prediction,
and control. There are four steps to the scientific method: formulating a research question,
framing the research question in the form of a hypothesis, testing the hypothesis, and drawing
conclusions about the correctness of the hypothesis. Psychologists follow the ethical principles
that govern research with human and nonhuman subjects. Two of the key ethical provisions
guiding research with human participants are informed consent and confidentiality.
Research samples need to be representative of the target population. The naturalistic observation
method allows scientists to measure behavior under naturally occurring conditions. Correlational
research explores the relationship between variables, which may help predict future behavior and
suggest possible underlying causes of behavior. But correlational research does not directly test
cause-and-effect relationships. Longitudinal research is a type of correlational design that
involves the study of selected subjects at periodic intervals over long periods of time, sometimes
In the experimental method, the investigator directly controls or manipulates the independent
variable under controlled conditions in order to demonstrate cause-and-effect relationships.
Experiments use random assignment as the basis for determining which subjects (called
experimental subjects) receive an experimental treatment and which others (called control
subjects) do not. Researchers use various methods, including single-blind placebo-control
studies, double-blind placebo control studies, and attention-placebo control studies to attempt to
control for subjects' and researchers' expectations.
Experiments are evaluated in terms of their experimental validity. Internal validity refers to the
ability of an experimental study to justify a cause-and-effect relationship between the
independent and dependent variables. Internally valid studies control for possible confounds, or
rival hypotheses. External validity refers to the degree to which experimental results can be
generalized to other subjects, settings, and times. Construct validity refers to the degree to which
treatment effects can be accounted for by the theoretical mechanisms, or constructs, that are
represented by the independent variables.
The epidemiological method examines the rates of occurrence of abnormal behavior in various
population groups or settings. Evidence of how disorders cluster in certain groups or geographic
areas may reveal underlying causes. Kinship studies attempt to disentangle the contributions of
environment and heredity.
Case-study methods can provide a richness of clinical material, but they are limited by
difficulties of obtaining accurate and unbiased client histories, by possible therapist biases, and
by the lack of control groups. Single-case experimental designs are intended to help researchers
overcome some of the limitations of the case-study method.
I. How Do We Define Abnormal Behavior?
A. Criteria for Determining Abnormality
B. Cultural Biases of Abnormal Behavior
II. Historical Perspectives on Abnormal Behavior
A. The Demonological Model
B. Origins of the Medical Model: In "Ill Humor"
C. Medieval Times
F. The Reform Movement and Moral Therapy
G. A Step Backward
H. The Community Mental Health Movement: The Exodus from State Hospitals
I. Contemporary Perspectives on Abnormal Behavior
1. The Biological Perspective
2. The Psychological Perspective
3. The Sociocultural Perspective
4. The Biopsychosocial Perspective
III. Research Methods in Abnormal Psychology
A. Description, Explanation, Prediction, and Control: The Objectives of Science
B. The Scientific Method
C. Ethics in Research
D. Naturalistic Observation
E. The Correlational Method
F. The Experimental Method
1. Experimental and Control Subjects
2. Controlling for Subjects' Expectations
3. Experimental Validity
G. Epidemiological Studies
H. Kinship Studies
1. Twin Studies
2. Adoptee Studies
I. Case Studies
1. Types of Case Studies
2. The Single-Case Experimental Design
IV. Summing Up
Discuss six criteria that are used to define abnormal behavior.
Discuss the relationships between cultural beliefs and norms and the labeling of
behavior as normal or abnormal.
Recount the history of beliefs about disturbed behavior and the treatment of people
deemed “mad” or mentally ill.
Discuss societal factors that contributed to “Homosexuality” being a diagnosable
disorder then being removed from the DSM in 1973.
Discuss the following contemporary perspectives on abnormal behavior: biological,
psychodynamic, learning-based, humanistic, cognitive, and sociocultural.
Discuss the steps involved in the scientific method.
Explain how experimenters control for subjects’ and researchers’ expectations, and
explain the differences among three types of experimental validity.
Discuss the various methods used to study abnormal behavior, including the
naturalistic, observation method, the correlational method, the experimental method,
kinship studies, the epidemiological method, and the case-study method.
on Abnormal Behavior
The Biological Perspective
Abnormal behavior may be viewed from various contemporary perspectives. The medical model
conceptualizes abnormal behavior patterns like physical diseases, in terms of clusters of
symptoms, called syndromes, which have distinctive causes that are presumed to be biological in
nature. Biological perspectives incorporate the medical model but refer more broadly to
approaches that relate abnormal behavior to biological processes and apply biologically based
The Psychological Perspective
Psychodynamic models reflect the views of Freud and his followers, who believed that abnormal
behavior stemmed from psychological causes involving underlying psychic forces. Freud
developed psychoanalysis as a means of uncovering the unconscious conflicts dating back to
childhood that he believed were at the root of mental disorders such as hysteria.
Learning theorists posit that the principles of learning can be used to explain both abnormal and
normal behavior. Behavior therapy is an outgrowth of the learning model.
Humanists reject the determinism of psychodynamic theory and behaviorism. Humanistic
theorists believe that it is important to understand the obstacles that people encounter as they
strive toward self-actualization and authenticity.
Cognitive theorists focus on the role of distorted and self-defeating thinking in explaining
abnormal behavior. They apply some of the behavioral techniques to cognitive therapies.
The Sociocultural Perspective
Sociocultural theorists believe that abnormal behavior is rooted in social ills, such as poverty,
discrimination, and social stressors, not in the individual. Today, many theorists believe that
multiple factors interacting in complex ways are involved in the development of abnormal
The Biopsychosocial Perspective
The leading interactionist model, the diathesis-stress model, posits that some people have
predispositions (diathesis) for particular disorders, but whether these disorders actually develop
depends upon the type and severity of the stressors they experience.
I. The Biological Perspective
A. The Nervous System
B. Evaluating Biological Perspectives on Abnormal Behavior
II. The Psychological Perspective
A. Psychodynamic Models
B. Learning Models
C. Humanistic Models
D. Cognitive Models
III. The Sociocultural Perspective
A. Ethnicity and Mental Health
B. Evaluating the Sociocultural Perspective
IV. The Biopsychosocial Perspective
A. The Diathesis-Stress Model
B. Evaluating the Biopsychosocial Model
C. The Case of Jessica -- A Final Word
V. Summing Up
1. To be able to differentiate among the Biological, Psychological, Sociocultural, and
Biopsychosocial perspectives and to be able to discuss the merits and limitations of each.
Identify and describe the key areas of the brain and a neuron and their related
functions, activities, and influences on behavior.
To be able to conceptualize the role of genes, and their limitations, in influencing
To be able to think critically about cultural and societal influences, which contribute
to differential rates of psychopathology among various ethnic groups in the United States
and around the world.
Identify and describe emotional, social, environmental, cultural, and biological
influences on human behavior.
6. Understand the interplay of emotion, social and cultural conditions, environment, and
biological (genetic and nongenetic) factors in determining the manifestation of normal
and abnormal behaviors.
Classification and Assessment
of Abnormal Behavior
Classification of Abnormal Behavior
Diagnostic classification may be traced as far back as Hippocrates, but was ushered into the
modern era by Kraepelin in the late nineteenth century. His classification system influenced the
development of the Diagnostic and Statistical Manual of Mental Disorders (DSM), which is
the most widely accepted diagnostic system, now in its fourth edition.
The DSM uses specific diagnostic criteria to group patterns of abnormal behaviors that share
common clinical features and a multiaxial system of evaluation. Strengths of the DSM include its
use of specified diagnostic criteria and a multiaxial system to provide a comprehensive picture of
the person's functioning. Weaknesses include questions about reliability and validity, and about
the medical model framework.
Issues of Reliability and Validity in Assessment
Methods of assessment must be reliable and valid. Reliability of assessment techniques is shown
in various ways, including internal consistency, temporal stability, and interrater reliability.
Validity is measured by means of content validity, criterion validity, and construct validity.
Methods of Assessment
The clinical interview is the most widely used method of assessment. It involves the use of a set
of questions designed to elicit relevant information from people seeking treatment. Clinicians
generally use a structured interview, which consists of a fairly standard series of questions to
gather a wide range of information concerning presenting problems or complaints, present
circumstances, and history.
Psychological tests are structured methods of assessment that are used to evaluate reasonably
stable traits such as intelligence and personality. Tests of intelligence, like the Stanford-Binet
and the Wechsler scales, are used for various purposes in clinical assessment, including
determining evidence of mental retardation or cognitive impairment, and assessing strengths and
weaknesses. Intelligence is expressed in the form of an intelligence quotient (IQ). Self-report
personality inventories, like the MMPI and MCMI, use structured items to measure various
personality traits, such as anxiety, depression, and masculinity-femininity. These tests are
considered objective in the sense that they make use of a limited range of possible responses to
items and an empirical, or objective, method of test construction. Projective personality tests,
such as the Rorschach and TAT, ask subjects to interpret ambiguous stimuli in the belief that
their answers may shed light on the unconscious processes. Concerns persist about the validity of
these tests, however.
Methods of neuropsychological assessment help determine organic bases for impaired behavior
and psychological functioning. The Bender Visual Motor Gestalt Test requires subjects to
reproduce nine geometric designs on a piece of paper. The Halstead-Reitan Neuropsychological
Battery and Luria Nebraska Test Battery are more sophisticated batteries of tests measuring
various perceptual, intellectual, and motor skills and performance.
In behavioral assessment, test responses are taken as samples of behavior rather than as signs of
underlying traits or dispositions. The behavioral examiner may conduct a functional assessment,
which relates the problem behavior to its antecedents and consequences. Methods of behavioral
assessment include behavioral interviewing, self-monitoring, use of analogue or contrived
measures, direct observation, and behavioral rating scales.
Cognitive assessment focuses on the measurement of thoughts, beliefs, and attitudes in order to
help identify distorted thinking patterns. Specific methods of assessment include the use of a
thought record or diary and the use of rating scales such as the Automatic Thoughts
Questionnaire (ATQ), the Cognitive Checklist (CCL), and the Dysfunctional Attitudes Scales
Measures of physiological function include heart rate, blood pressure, galvanic skin response
(GSR), muscle tension, and brain wave activity. Brain-imaging techniques such as EEG, CAT
scans, PET scans, MRI, and BEAM probe the inner workings and structures of the brain.
I. How Are Abnormal Behavior Patterns Classified?
A. The DSM and Models of Abnormal Behavior
1. Features of the DSM
2. Culture Bound Syndromes
3. Evaluation of the DSM System
4. Advantages and Disadvantages of the DSM System
II. Standards of Assessment
1. Internal Consistency
2. Test-retest Stability
3. Interrater Reliability
1. Content Validity
2. Criterion Validity
3. Construct Validity
III. Methods of Assessment
A. The Clinical Interview
1. Interview Formats
B. Psychological Tests
1. Intelligence Tests
2. Self Report Personality Tests
3. Projective Tests
C. Neuropsychological Assessment
1. The Bender Visual Motor Gestalt Test
2. The Halstead-Reitan Neuropsychological Battery
3. The Luria Nebraska Battery
D. Behavioral Assessment
2. Analogue Measures
3. Behavioral Rating Scales
E. Cognitive Assessment
1. Methods of Cognitive Assessment
F. Physiological Measurement
1. Brain Imaging and Recording Techniques
IV. Sociocultural and Ethnic Factors in the Assessment
V. Summing Up
Discuss historical origins of modern diagnostic systems and the development of the
Describe the features of the DSM system and evaluate its strengths and weaknesses.
Describe approaches used by investigators to demonstrate the reliability and validity of
methods of assessment.
Describe the features of the mental status examination and different types of
Describe the features of tests of intelligence and personality.
Describe the use of psychological tests in the assessment of neuropsychological
Discuss the advantages and limitations of behavioral assessment, and describe the
following behavioral techniques: the behavioral interview, self-monitoring, use of
analogue measures, and behavioral rating scales.