Chapter 3
Models of Abnormality
Models of Abnormality
In science, the perspectives used to explain phenomena
are known as models or paradigms
Each provides a set of assumptions and concepts that help us
explain and interpret observations
A school of thought
Helpful because they spell out basic assumptions and set
guidelines for investigation
They influence what investigators observe, the questions they
ask, the information they seek, and their interpretation of
that information
Models of Abnormality
Historically, clinical scientists of a given time
and place agreed on a single model of
abnormality – a model greatly influenced by
cultural beliefs
Currently, there are several competing models of
abnormality
Why? Each model focuses on one aspect of human
functioning and no single model can explain all
aspects of abnormality
The Biological Model
Takes a medical perspective
Main focus is that psychological abnormality is
an illness brought about by malfunctioning parts
of the organism
Typically focused on the brain
Four factors that are associated with this approach
1.
Influence of germs
2.
Genetic links
3.
Biochemical changes
4.
Neuroanatomical changes
How Do Biological Theorists
Explain Abnormal Behavior?
Brain anatomy
The brain is composed of ~100 billion nerve cells
(called neurons) and thousands of billions of
support cells (called glia)
Within the brain, large groups of neurons form
distinct areas called brain regions
How Do Biological Theorists
Explain Abnormal Behavior?
Brain anatomy and abnormal behavior
Clinical researchers have found connections between
certain psychological disorders and problems in
specific brain areas
Example: Huntington’s disease & basal ganglia (forebrain)
How Do Biological Theorists
Explain Abnormal Behavior?
Brain chemistry
Information spreads throughout the brain in the
form of electrical impulses that travel from one
neuron to one (or more) other neurons
An impulse is first received at a neuron’s dendrites,
travels down the axon, and is transmitted to other
neurons through the nerve endings
Brain Anatomy and Abnormal Behavior
The brain is composed of ~ 100 billion nerve cells or
neurons and thousands of billions of support cells or glia
Large groups of neurons
form brain regions:
Distinct areas that control
important functions
Clinical researchers have
discovered connections
between certain
psychological disorders and
specific areas
Huntington’s Disease – loss of
cells in the basal ganglia
(forebrain)
10
How Do Biological Theorists
Explain Abnormal Behavior?
Brain chemistry
Neurons don’t touch; they are separated by a space
(the synapse), across which a message moves
When an electrical impulse reaches a nerve ending,
the nerve ending is stimulated to release a chemical
called a neurotransmitter (NT)
Some NTs tell receiving neurons to “fire;” other NTs tell
receiving neurons to stop firing
How Do Biological Theorists
Explain Abnormal Behavior?
Brain chemistry
Researchers have identified dozens of NTs
Examples: serotonin, dopamine, and GABA
Studies indicate that abnormal activity in certain NTs
can lead to specific mental disorders
Examples: depression (serotonin and norepinephrine) and
anxiety (GABA)
Recent studies have focused on the role of NT in their impact
on behavior
Acetylcholine - first known NT. it is involved with
transmission to muscles.
Dopamine - regulates motor behavior, excess dopamine is
thought to be a cause of schizophrenia. It is developed in
the mid-brain above the pons.
Enkephalines - opiate receptors, affected by opium derivatives,
may be able to produce natural highs. May be the source of
runners high.
GABA - gamma-amino-butyric-acid, an inhibitory NT.
Histamines - allergic reactions
Norephinephrine - acts on autonomic nervous system to
produce energizing responses.
Serotonin - transmissions within the brain, may play a role in
depression.
How Do Biological Theorists
Explain Abnormal Behavior?
Brain chemistry
Additionally, researchers have learned that mental disorders
are sometimes related to abnormal chemical activity in the
endocrine system
Hormone release, triggered by a variety of factors, propels
body organs into action. Abnormal secretions have been
linked to psychological disorders
Example: cortisol release is related to anxiety and mood
disorders
How Do Biological Theorists
Explain Abnormal Behavior?
Sources of biological abnormalities – Genetics
Humans have 23 pairs of chromosomes, each with numerous
genes that control the characteristics and traits a person
inherits
Studies suggest that inheritance plays a part in mood
disorders, schizophrenia, mental retardation, Alzheimer’s
disease, and other mental disorders
Aren’t able (yet) to identify specific genes
Don’t know the extent to which genetic factors contribute to
disorders
Seems no SINGLE gene is responsible for a particular behavior
or disorder
Causes of Biological Abnormalities
Genetic Inheritance
Each cell in the human body contains 23 pairs of chromosomes
Studies suggest inheritance plays a role in:
Mood disorders
Schizophrenia
Mental retardation
Alzheimer’s disease
Genes combine to help produce our functional and dysfunctional
actions
Inherited from a person’s parents
Cells contain between 30,000 - 40,000 genes that control the characteristics
and traits being inherited
In most cases no single gene is responsible for particular behavior or mental
disorder
Human Gnome Project
Research to identify which genes help cause various human disorders
Behavior genetics - examines influence of genes on behavior
• Genotype - a unique genetic code, a persons genetic makeup
• Phenotype - behavioral expression of the interaction of
genotype and the environment. Often it is difficult to
determine which is predominant --> nature vs. nurture
controversy.
Twin studies are often used to study genetic/environment
interactions
Two types of twins
• Monozygotic (MZ) - identical twins, develop from 1
fertilized egg. They have the exact same genotype. Do
they have the same phenotype?
• Dizygotic (DZ) - fraternal twins, develop from 2 eggs
fertilized by 2 different sperm. They have less than 50% of
their genes in common.
Studies of Concordance - when twins develop the same
disorder
Research studies use groups of MZ twins that are compared
to DZ twins. If the concordance rate is higher in MZ (3:1)
than in DZ twins, then it is likely their is a genetic
connection for that disease.
If their is little concordance in the MZ twins it may be due to
interaction with the environment or some other cause.
Recent studies of MZ twins have found
high concordance rates in
anxiety reactions
alcoholism
schizophrenia
depression
How Do Biological Theorists
Explain Abnormal Behavior?
Sources of biological abnormalities – Evolution
Genes that contribute to mental disorders are viewed as
unfortunate occurrences:
May be mutations
May be inherited after a mutation in the family line
Evolutionary theorists argue that we can best understand
abnormality by examining the millions of years of human
evolution
Looking at a combination of adaptive behaviors of the past, genes,
and the interaction between genes and current environmental events
This model has been criticized and remains controversial
How Do Biological Theorists
Explain Abnormal Behavior?
Sources of biological abnormalities – Viral
infections
Infection provides another possible source of
abnormal brain structure or biochemical dysfunction
Example: schizophrenia and prenatal viral exposure
Interest in viral explanations of psychological
disorders has been growing in the past decade
Example: anxiety and mood disorders
Biological Treatments
Biological practitioners attempt to pinpoint the
physical source of dysfunction to determine the
course of treatment
Three types of biological treatment:
Drug therapy
Electroconvulsive therapy (ECT)
Psychosurgery
Biological Treatments
Drug therapy:
1950s = advent of psychotropic medications
Changed outlook for a number of mental disorders
Four groups of drugs:
Antianxiety drugs (anxiolytics; tranquilizers)
Antidepressant drugs
Antibipolar drugs (mood stabilizers)
Antipsychotic drugs
Biological Treatments
Electroconvulsive therapy (ECT):
Currently experiencing a revival
Used for depression when drugs and other therapies
have failed
In 60% of cases, ECT can lift symptoms within a few
weeks
Biological Treatments
Psychosurgery (or neurosurgery):
Historical roots in trephination
1930s = first lobotomy
Much more precise than in the past
Considered experimental and used only in extreme
cases
Measuring the brain
Other forms of brain study are needed to study brain function
and structure.
• early methods - dissections
• advanced
CT and MRI scans study brain structure.
Pet scans study brain function
CT (CAT) scan - computerized axial tomography,
passes gamma-rays through cross-sections of the
intact brain and measures radioactivity on the other
side.
By locating differences in tissue density, tumors can be
located.
MRI - Nuclear magnetic resonance imaging. More precise and
detailed than CT.
Enclosed in a magnetic field, radio waves are used to locate
abnormalities in tissue. Very accurate, excellent details. Can be
used from different viewpoints to create different perspectives
for different dimensional views.
PET - Positron Emission Tomography - (a measure of brain
activity) observes brain activity by monitoring an injected
radioactive tracer substance moving though blood vessels of
the brain.
Studies have shown that schizophrenics have greater blood flow to the
left hemisphere of the brain than the rt. hemi. The more severe the
schiz. the greater the difference in left/right blood flow. One
conclusion has been drawn, Schiz. is the result of left hemi. damage,
greater blood flow is the bodies attempt to compensate.
Assessing the Biological Model
Strengths:
Enjoys considerable
respect in the field
Fruitful
Creates new therapies
Suggests new avenues of
research
Weaknesses:
Can limit rather than
enhance our
understanding
Too simplistic
Evidence is incomplete or
inconclusive
Treatments produce
significant undesirable
(negative) effects
The Psychodynamic Model
Oldest and most famous psychological model
Based on belief that a person’s behavior (whether
normal or abnormal) is determined largely by
underlying dynamic psychological forces of which she
or he is not aware
Abnormal symptoms are the result of conflict among these
forces
Father of psychodynamic theory and psychoanalytic
therapy:
Sigmund Freud (1856 – 1939)
First hypothesis - became known as depth psychology
Two basic principles of this theory
I. Conflict causes anxiety
II. The mind works on 2 levels
1. Conscious mind, awareness, here and now
2. Unconscious mind, has 2 levels identifiable by the
retrievability of memories
What evidence do we have that the unconscious exists?
Second Hypothesis
Focus is on mental structures and instincts
Behavior is a product of 3 mental structures
Id
Ego
Superego
How Did Freud Explain
Normal and Abnormal Functioning?
Abnormal behavior is caused by three
UNCONSCIOUS forces:
1.
Id – guided by the Pleasure Principle
2.
Ego – the reality principle
3.
Superego – our values and ideals
The Id
Psychological force that produces instinctual needs,
drives, and impulses
Pleasure principle
Always seeks gratification
All id instincts tend to be sexual in nature
A person’s libido fuels the id
Instinctual needs, drives, & impulses
Sexual; fueled by libido (sexual energy)
2. Ego Function
1.
Ego – guided by the Reality Principle
Seeks gratification but guides us to know when we can
& can’t express our wishes
Ego defense mechanisms protect us from anxiety
The Ego
Psychological force that employs reason
Once we realize our environment will not meet every
instinctual need, part of the id separates into the ego
Unconsciously seeks gratification
Reality principle
Knowledge that it can be unacceptable to express our id impulses
outright
The ego guides us to know when we can and cannot express
impulses
Ego Defense Mechanisms
Basic strategies to control unacceptable id impulses
Repression – the most basic
prevents these impulses from reaching consciousness
The Superego
The psychological force that represents a person’s values
and ideas
Grows out of the ego
Development of a conscious
Based on feelings of doing good vs. guilt
As we learn that many of our id impulses are
unacceptable, we unconsciously adopt certain values
How Did Freud Explain
Normal and Abnormal Functioning?
These three parts of the personality are often
in conflict
A healthy personality is one in which compromise
exists among the three forces
If the id, ego, and superego are in excessive
conflict, the person’s behavior may show signs of
dysfunction
How Did Freud Explain
Normal and Abnormal Functioning?
Developmental stages
Freud proposed that at each stage of development,
new events and pressures require adjustment in the
id, ego, and superego
If successful → personal growth
If unsuccessful → fixation at an early developmental
stage, leading to psychological abnormality
Because parents are the key figures in early life, they are often
seen as the cause of improper development
How Did Freud Explain
Normal and Abnormal Functioning?
Developmental stages
Oral (0 to 18 months of age)
Anal (18 months to 3 years of age)
Phallic (3 to 5 years of age)
Latency (5 to 12 years of age)
Genital (12 years of age to adulthood)
How Do Other Psychodynamic
Explanations Differ from Freud’s?
Although current models deviate from Freud’s in
important ways, each retains the belief that human
functioning is shaped by dynamic (interacting) forces:
Ego theorists
Self theorists
Emphasize the role of the ego; consider it independent
Emphasize the unified personality over any one component
Object-relations theorists
Emphasize the human need for interpersonal relationships
Psychodynamic Therapies
Range from Freudian psychoanalysis to more
modern therapies
All seek to uncover past trauma and inner
conflicts
Understanding early life experience critically
important
Therapist acts as “subtle guide”
Psychodynamic Therapies
Utilize various techniques:
Free association
Therapist interpretation
Resistance
Transference
Dream interpretation
Catharsis
Working through
Psychodynamic Therapies
Contemporary trends:
Short-term psychodynamic therapies
Relational psychoanalytic therapy
Assessing the Psychodynamic
Model
Strengths:
First to recognize importance
of psychological theories &
treatment
Saw internal conflict as
important source of
psychological health and
abnormality
First to apply theory and
techniques systematically to
treatment – monumental
impact on the field
Weaknesses:
Unsupported ideas;
difficult to research
Non-observable
Inaccessible to human
subject (unconscious)
The Behavioral Model
Like the psychodynamic perspective,
behaviorism is deterministic, and is based on the
idea that our actions are determined largely by
our life experiences
Emphasizes observable behavior and
environmental factors
Focuses on how behavior is acquired (learned)
and maintained over time
The Behavioral Model
Historical beginnings in laboratories where
conditioning studies were conducted
Several forms of conditioning:
Operant conditioning
Modeling
Classical conditioning
May produce normal or abnormal behavior
How Do Behaviorists
Explain Abnormal Functioning?
Operant conditioning
Organism “operates” on environment and produces
an effect
Humans and animals learn to behave in certain ways
as a result of receiving rewards whenever they do so
Operant conditioning - operant behavior is a voluntary,
controllable behavior.
Thorndike’s (1874-1949) Law of Effect, the beginning of
Operant Conditioning
Animals repeat certain behaviors when those behaviors are
associated with positive consequences. Also, if the
consequences were unpleasant the behaviors would be
discouraged or reduced.
Principles of Operant conditioning
• Reinforcement - anything that increases the frequency or
magnitude of the behavior is a reinforcer.
-
both positive and negative reinforcers increase the
frequency of the desired behavior
- negative reinforcer, removes an aversive event.
• Punishment - either the removal of positive reinforcer, or the
presentation of an aversive condition.
• Extinction - elimination of a behavior through nonreinforcement.
• Shaping - reinforcing successive behaviors towards a goal
How Do Behaviorists
Explain Abnormal Functioning?
Modeling
Individuals learn behavioral responses by observing
and repeating behavior
No direct reinforcement
How Do Behaviorists
Explain Abnormal Functioning?
Classical conditioning
Learning by temporal association
When two events repeatedly occur close together in time,
they become fused in a person’s mind; before long, the
person responds in the same way to both events
Father of classical conditioning: Ivan Pavlov (1849 –
1936)
Classic study using dogs & meat powder
Classical Conditioning
US
UR
Meat
Salivate
US
UR
Meat
+
Tone
Salivate
CS
CR
Tone
Salivate
How Do Behaviorists
Explain Abnormal Functioning?
Classical conditioning
If, after conditioning, the CS is repeatedly presented
alone, it will eventually stop eliciting the CR
This process is called extinction
Explains many familiar behaviors (both normal and
abnormal)
Behavioral Therapies
Aim is to identify the behaviors that are causing
problems and replace them with more
appropriate ones
May use classical conditioning, operant conditioning,
or modeling
Therapist is “teacher” rather than healer
Early life experiences important only in providing
clues to current learning
Fear and Anxiety
Some symptoms can be treated by breaking the CS-CR bond.
Counter-conditioning - recognized early conditioning that has
led to the symptoms. Negative stimulus is paired with a
pleasant or neutral stimulus until the fear or anxiety is gone.
EG. Systematic desensitization
Flooding - exposure to the feared stimulus
Behavioral Therapies
Classical conditioning treatments may be used to
change abnormal reactions to particular stimuli
Example: systematic desensitization for phobia
Step-by-step procedure
Learn relaxation skills
Develop a fear hierarchy
Confront feared situations (covertly or in vivo)
Assessing the Behavioral Model
Strengths:
Weaknesses:
Powerful force in the field
Too simplistic
Rooted in empiricism
Unrealistic
Downplays role of
cognition
Phenomena can be
observed and measured
Significant research
support for behavioral
therapies
New focus on self-efficacy,
social cognition, and
cognitive-behavioral
theories
Explanations for symptoms using the behavioral model.
- Following the funeral of his grandfather, a 7 yr. old child
becomes extremely fearful of riding in cars, especially black
cars.
- A middle-aged women begins to feel nauseous and
frequently vomits in the parking lot of the hospital when
she arrive for her cancer chemotherapy.
- Heroin user overdoses and dies when they are injected with
their typical fix, but without having prepared the drug
themselves.
The Cognitive Model
Seeks to account for behavior by studying the
ways in which the person attends to, interprets,
and uses available information
Argues that clinicians must ask questions about
assumptions, attitudes, and thoughts of a client
Concerned with internal processes
Present-focused
How Do Cognitive Theorists
Explain Abnormal Functioning?
Maladaptive thinking is the cause of maladaptive
behavior
Several kinds of faulty thinking:
Faulty assumptions and attitudes
Illogical thinking processes
Example: overgeneralization
Cognitive Therapies
People must be taught a new way of thinking to
prevent maladaptive behavior
Main model: Beck’s Cognitive Therapy
The goal of therapy is to help clients recognize and
restructure their thinking
Therapists also guide clients to challenge dysfunctional thoughts,
try out new interpretations, and apply new ways of thinking in
their daily lives
Widely used in treating depression
Assessing the Cognitive Model
Strengths:
Very broad appeal
Clinically useful & effective
Focuses on a uniquely human
process
Weaknesses:
Singular, narrow focus
Overemphasis on the
present
Correlation between symptoms
and maladaptive cognition
Limited effectiveness
Therapies effective in treating
several disorders
Verification of cognition
is difficult
Adapt well to technology
Research-based
Precise role is hard to
determine
The Humanistic-Existential
Model
Combination model
The humanist view
Emphasis on people as friendly, cooperative, and
constructive; focus on drive to self-actualization
The existentialist view
Emphasis on self-determination, choice, and individual
responsibility; focus on authenticity
Rogers’ Humanistic
Theory and Therapy
Basic human need for unconditional positive regard
If received, leads to unconditional self-regard
If not, leads to “conditions of worth”
Incapable of self-actualization because of distortion – don’t know
what they really need, etc.
Rogers’ “client-centered” therapy
Therapist provides unconditional positive regard
Both accurate & genuine in reflection (reflective listening)
Focus on the “experiencing person”
Little research support
Gestalt Theory and Therapy
Humanistic approach
Developed by Fritz Perls
Goal is to help clients achieve self-recognition
through challenge and frustration
Techniques:
Skillful frustration
Role playing
Rules, including “Here and Now” and “I” language
Existential Theories and Therapy
Psychological dysfunction is caused by selfdeception: people hide from life’s responsibilities
and fail to recognize that it is up to them to give
meaning to their lives
Therapy is focused on patient acceptance of
personal responsibility and recognition of freedom
of action
Goals more important than technique
Great emphasis placed on client-therapist relationship
Assessing the HumanisticExistential Model
Strengths:
Emphasizes the individual
Taps into domains
missing from other
theories
Non-deterministic
Optimistic
Emphasizes health
Weaknesses:
Focuses on abstract issues
Difficult to research
Not much influence
Weakened by disapproval
of scientific approach
Changing somewhat
The Sociocultural Model
Argues that abnormal behavior is best
understood in light of the social and cultural
forces that influence an individual
Addresses norms and roles in society
Influenced by sociology and anthropology
Argues that we must examine a person’s social
surroundings to understand their (abnormal)
behavior
How Do Sociocultural Theorists
Explain Abnormal Functioning?
Focus on:
Societal labels & roles
Diagnostic labels (example: Rosenhan study)
Sick role
Social networks and support
How Do Sociocultural Theorists
Explain Abnormal Functioning?
Focus on:
Family structure and communication
Family systems theory = abnormal functioning within
family leads to abnormal behavior (insane behavior
becomes sane in an insane environment)
Examples: enmeshed, disengaged structures
How Do Sociocultural Theorists
Explain Abnormal Functioning?
Focus on:
Culture
Set of values, attitudes, beliefs, history, and behaviors
shared by a group of people and communicated from one
generation to the next
“Multicultural” psychology is a growing field of study
How Do Sociocultural Theorists
Explain Abnormal Functioning?
Focus on:
Religion and spirituality
For most of the twentieth century, clinical scientists
viewed religion as a negative factor in mental health but
this alienation now seems to be ending:
Researchers have begun to systematically study the influence of
religion and spirituality on mental health
Many therapists now address spiritual issues when treating
religious clients
Sociocultural Treatments
May include traditional individual therapy
Broadened therapy to include:
Culturally sensitive therapy
Group therapy
Family therapy
Couple therapy
Community treatment
Includes prevention work
Assessing the Sociocultural
Model
Strengths:
Added greatly to the
clinical understanding of
abnormality
Increased awareness of
labeling
Clinically successful when
other treatments have
failed
Weaknesses:
Research is difficult to
interpret
Correlation causation
Model unable to predict
abnormality in specific
individuals
Integration of the Models
Each perspective is valuable to understanding
abnormal behavior
Different perspectives are more appropriate
under differing conditions
An integrative approach provides a general
framework for thinking about abnormal
behavior, and also allows for specification of the
factors that are especially pertinent to particular
disorders
Integration of the Models
Many theorists, clinicians, and practitioners
adhere to a biopsychosocial model
Abnormality results from the interaction of genetic,
biological, developmental, emotional, behavioral,
cognitive, social, and societal influences
Also popular:
Diathesis-stress approach
Diathesis = predisposition (bio, psycho, or social)
Reciprocal effects explanation
Integration of the Models
Integrative therapists are often called “eclectic”
– taking the strengths from each model and
using them in combination
