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Transcript
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