Comer, Abnormal Psychology, 5th edition

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Transcript Comer, Abnormal Psychology, 5th edition

Chapter 3
Models of Abnormality
Models of Abnormality
 What is a model or paradigm?
• A set of assumptions and concepts that help us
explain and interpret observations
• A school of thought
• Helpful because it spells out basic assumptions
and sets guidelines for investigation
• It influences what investigators observe, the
questions they ask, the information they seek, and
their interpretation of that information
Slide 2
Models of Abnormality
 Historically, clinical scientists of a given time
and place agreed on a single model of
abnormality – a model strongly 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
Slide 3
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
Slide 4
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
Slide 5
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)
Slide 6
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 others
• An impulse is first received at a neuron’s
dendrites, travels down the axon, and is
transmitted to other neurons through the nerve
endings
Slide 7
Slide 8
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 (a neurotransmitter or “NT”)
• Some NTs tell receiving neurons to “fire”; other NTs
tell receiving neurons to stop firing
Slide 9
How Do Biological Theorists
Explain Abnormal Behavior?
 Role of brain chemistry in abnormal behavior
• 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)
Slide 10
How Do Biological Theorists
Explain Abnormal Behavior?
 Role of 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
Slide 11
How Do Biological Theorists
Explain Abnormal Behavior?
 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
Slide 12
How Do Biological Theorists
Explain Abnormal Behavior?
 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
Slide 13
How Do Biological Theorists
Explain Abnormal Behavior?
 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
Slide 14
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
Slide 15
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
Slide 16
Biological Treatments
 Electroconvulsive therapy (ECT):
• Currently experiencing a revival
• Used for severe depression when drugs and other
therapies have failed
• In 60% of cases, ECT can lift symptoms within a few
weeks
Slide 17
Biological Treatments
 Psychosurgery:
• Historical roots in trephination
• 1930s = first lobotomy
• Much more precise than in the past
• Considered experimental and used only in
extreme cases
Slide 18
Assessing the Biological Model
 Strengths:
• Earns 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
Slide 19
The Psychodynamic Model
 Oldest and most famous psychological model
 Based on belief that a person’s behavior 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)
Slide 20
How Did Freud Explain
Normal and Abnormal Behavior?
 Caused by three UNCONSCIOUS forces:
1. Id – guided by the Pleasure Principle
•
Instinctual needs, drives, & impulses
•
Sexual; fueled by libido (sexual energy)
2. Ego – guided by the Reality Principle
•
Seeks gratification but guides us to know when we
can & can’t get and express our wishes
•
Ego defense mechanisms protect us from anxiety
Slide 21
Slide 22
How Did Freud Explain
Normal and Abnormal Behavior?
 Caused by three UNCONSCIOUS forces:
3. Superego – guided by the Morality Principle
•
Conscience; unconsciously adopted from our parents
 These three parts of the personality are often in
conflict
•
A healthy personality is one in which compromise exists
between the parts
•
If the id, ego, and superego are in excessive conflict, the
person’s behavior may show signs of dysfunction
Slide 23
How Did Freud Explain
Normal and Abnormal Behavior?
 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
Slide 24
How Did Freud Explain
Normal and Abnormal Behavior?
 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)
Slide 25
How Do Other Psychodynamic
Explanations Differ from Freud’s?
 Although current models deviate from Freud’s in
fundamental ways, each retains the belief that
human functioning is shaped by interacting forces:
• Ego theorists
• Emphasize the role of the ego; consider it independent
• Self theorists
• Emphasize the unified personality over any one component
• Object-relations theorists
• Emphasize the human need for interpersonal relationships
Slide 26
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”
Slide 27
Psychodynamic Therapies
 Utilize various techniques:
• Free association
• Therapist interpretation
• Resistance
• Transference
• Dream interpretation
• Catharsis
• Working through
• Short-term dynamic therapies
Slide 28
Assessing the Psychodynamic Model
 Strengths:
• First to recognize importance
of psychological theories &
treatment
• Saw internal conflict as
important source of
psychological health and
abnormality
 Weaknesses:
• Unsupported ideas;
difficult to research
• Non-observable
• Inaccessible to human
subject (unconscious)
• First to apply theory and
techniques systematically to
treatment – monumental
impact on the field
Slide 29
Slide 30
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
 Emphasis is on observable behavior and
environmental factors
 Focus on how behavior is acquired (learned)
and maintained over time
Slide 31
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
Slide 32
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
Slide 33
How Do Behaviorists
Explain Abnormal Functioning?
 Modeling
• Individuals learn behavioral responses by
observing and repeating behavior
• No direct reinforcement
Slide 34
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
Slide 35
Classical Conditioning
US
UR
Meat
Salivate
US
UR
Meat
+
Tone
Salivate
CS
CR
Tone
Salivate
Slide 36
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)
Slide 37
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
Slide 38
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)
Slide 39
Assessing the Behavioral Model
 Strengths:
 Weaknesses:
• Powerful force in the
field
• Too simplistic
• Rooted in empiricism
• Downplays role of
cognition
• Phenomena can be
observed and measured
• Significant research
support for behavioral
therapies
• Unrealistic
• New focus on selfefficacy, social cognition,
and cognitive-behavioral
theories
Slide 40
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
• Concerned with internal processes
• Present-focused
Slide 41
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
Slide 42
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
Slide 43
Assessing the Cognitive Model
 Strengths:
• Broad appeal
• Clinically useful & effective
• Focuses on a uniquely human
process
• Correlation between
symptoms and maladaptive
cognition
• Therapies effective in
treating several disorders
• Adapt well to technology
 Weaknesses:
• Singular, narrow focus
• Overemphasis on the
present
• Limited effectiveness
• Verification of cognition
is difficult
• Precise role is hard to
determine
• Research-based
Slide 44
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
Slide 45
Spiritual Views and Interventions
 For most of the twentieth century, clinical scientists
viewed religion as a negative factor in mental health
 This alienation now seems to be ending:
• Numerous books have been published
• Ethical codes now include religion under “diversity”
• 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
Slide 46
Assessing the HumanisticExistential Model
 Strengths:
 Weaknesses:
• Emphasizes the
individual
• Focuses on abstract
issues
• Taps into domains
missing from other
theories
• Not much influence
• Non-deterministic
• Optimistic
• Weakened by
disapproval of scientific
approach
• Changing somewhat
• Emphasizes health
Slide 47
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
Slide 48
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
• Role of culture
• Role of social networks/support
Slide 49
How Do Sociocultural Theorists
Explain Abnormal Functioning?
 Focus on:
• Societal conditions
• Abnormality more common in lower classes. Why?
• Societal labels & roles
• Diagnostic labels (example: Rosenhan study)
• Sick role
Slide 50
Sociocultural Treatments
 May include traditional individual therapy
 Broadened therapy to include:
• Culturally-sensitive therapy
• Group therapy
• Family therapy
• Couples therapy
• Community treatment
• Includes prevention work
Slide 51
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
Slide 52
Slide 53
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 while also allowing for specification
of the factors that are especially pertinent to
particular disorders
Slide 54