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PSYCHOLOGY
Third Canadian Edition
Chapter 6
Anxiety Disorders
Prepared by:
Tracy Vaillancourt, Ph.D.
Types of Anxiety Disorders
•
•
•
•
•
•
Phobias
Panic Disorder (PD)
Generalized Anxiety Disorder (GAD)
Obsessive-Compulsive Disorder (OCD)
Post-Traumatic Stress Disorder (PTSD)
Acute Stress Disorder
Summary: Table 6.1
Disorder
Description
Phobia
Fear and avoidance of objects or situations that do not present any
real danger.
Panic Disorder
Recurrent panic attacks involving a sudden onset of physiological
symptoms, such as dizziness, rapid heart rate, and trembling,
accompanied by terror and feelings of impending doom; sometimes
accompanied with agoraphobia, a fear of being in public places.
Generalized Anxiety Disorder
Persistent, uncontrollable worry, often about minor things.
Obsessive-Compulsive Disorder
The experience of uncontrollable thoughts, impulses, or images
(obsessions) and repetitive behaviours or mental acts
(compulsions).
Post-traumatic Stress Disorder
Aftermath of a traumatic experience in which the person
experiences increased arousal, avoidance of stimuli associated
with the event, and anxiety in recalling the event.
Acute Stress Disorder
Symptoms are the same as those of post-traumatic stress disorder,
but last for four weeks or less.
Prevalence (past year)
In Ontario
• 16% of women and 9% of men suffered from anxiety disorders
• highest one-year prevalence rates found in women 15 to 24 years of
age
In Canada
• 4.7% of 15 years of age or older met diagnostic criteria for anxiety
disorder
– 1.6 % panic disorder
– 0.7 agoraphobia
– 3.9 % social anxiety disorder
• 11.5% reported symptoms of anxiety
– 3.7% panic disorder
– 1.5% agoraphobia,
– 8.1% social anxiety disorder
• Anxiety disorders are more common in women than in men across
all age groups and decrease with age
Phobias
• Phobia—disrupting, fear-mediated avoidance
that is out of proportion to the danger actually
posed and is recognized by the sufferer as
groundless.
• Examples of common phobias
–
–
–
–
Claustrophobia- fear of closed spaces
Agoraphobia- fear of public places
Acrophobia- fear of heights.
Mysophobia- fear of contamination and dirt
Specific Phobias
• Specific phobias— unwarranted fears caused by the
presence or anticipation of a specific object or situation
• Phobias sub-divided according to source of fear:
–
–
–
–
blood, injuries, and injections
situations (e.g., planes, elevators, enclosed spaces)
animals
natural environment (e.g., heights, water)
• Evidence to support the grouping of fears into 5 factors:
(1) agoraphobia
(2) fears of heights or water
(3) threat fears (e.g., blood/needles, storms/thunder)
(4) fears of being observed
(5) speaking fears
Social Phobia (SP)
• Social phobias— persistent, irrational fears
linked generally to the presence of other people.
– can be extremely debilitating
– people with a SP try to avoid situations in which they
might be evaluated because they fear that they will
reveal signs of anxiousness or behave in an
embarrassing way.
• Examples:
– speaking or performing in public
– eating in public,
– using public lavatories
Social Phobias cont.
• Social phobias can be either generalized or specific
– generalized SP involve many different interpersonal situations
– specific SP involve intense fear of one particular situation (e.g.,
public speaking).
• Generalized SP has an earlier age of onset and is more
co-morbid with other disorders than specific SP
• Lifetime prevalence
– 11% in men
– 15% in women
Etiology of Phobias
• Psychoanalytic Theory
– Phobias are a defence against the anxiety
produced by repressed id impulses
Etiology of Phobia (cont.)
• Behavioural Theories
– Focus on learning as the way in which
phobias are acquired
– Several types of learning may be involved
• Avoidance Conditioning— reactions are learned
avoidance responses
– avoidance-conditioning formulation
– phobias develop from two related sets of learning:
» 1. Via classical conditioning
» 2. Person learns to reduce conditioned fear by
escaping from or avoiding the CS (operant
conditioning)
Behavioural Theories (cont)
• Modelling—person can also learn fears through imitating the
reactions of others.
– learning of fear by observing others is referred to as vicarious learning.
• Prepared Learning—people tend to fear only certain objects and
events
– Fear spiders, snakes, and heights but not lambs
– Some fears may reflect classical conditioning, but only to stimuli to
which an organism is physiologically prepared to be sensitive
• Is a diathesis needed?
– Cognitive diathesis such as the tendency to believe that similar
traumatic experiences will occur in the future or not being able to control
the environment may be important in developing a phobia.
• Social Skills Deficits in Social Phobias
– inappropriate behaviour or a lack of social skills the cause of social
anxiety
Etiology of Phobia (cont.)
Cognitive Theories
–
–
focus on how people’s thought processes can serve as a
diathesis and on how thoughts can maintain a phobia
Anxiety is related to being more likely to:
1.
2.
3.
attend to negative stimuli
interpret ambiguous information as threatening
believe that negative events are more likely than positive ones to
re-occur
Cognitive-behavioural models of social phobia
–
link social phobia to certain cognitive characteristics:
1.
2.
3.
attentional bias to focus on negative social information
perfectionistic standards for accepted social performances
high degree of public self-consciousness
Etiology of Phobia (cont.)
Predisposing Biological Factors
1. Autonomic Nervous System
– autonomic lability
2. Genetic factors
– Blood-and-injection phobia has a strong familial
association
• 64% have at least one first-degree relative with the same
disorder
• 3-4% prevalence in general population
– Prevalence of social and specific phobias higher than
average in first-degree relatives of patients
– Twin studies also provide support
Therapies for Phobias
Psychoanalytic Approach
• attempt to uncover the repressed conflicts believed to
underlie the extreme fear and avoidance characteristic of
disoder
Behavioural Approaches
• systematic desensitization
– in vivo exposure
– virtual reality exposure
• Flooding
• Cognitive approaches
– viewed with skepticism because of a central defining
characteristic of phobias
• phobic fear is recognized by the individual as excessive or
unreasonable.
• Cognitive-behavioural therapy
Therapies cont.
Biological Approaches
• Anxiolytics—Drugs that reduce anxiety
(sedatives and tranquilizers)
– Barbiturates—first major category of drugs used to
treat anxiety disorders and we supplanted in the
1950s by two other classes of drugs:
• propanediols (e.g., Miltown)
• benzodiazepines (e.g., Valium and Xanax).
– Today newer benzodiazepines such as Ativan and Clonapam
are prescribed
• monoamine oxidase (MAO) inhibitors and SSRIs also used to
treat SP
Panic Disorder
• Panic Attack—person suffers a sudden and
often inexplicable attack of of alarming
symptoms:
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–
–
–
–
–
laboured breathing, heart palpitations,
nausea and chest pain;
feelings of
choking and smothering;
dizziness, sweating, and trembling;
intense apprehension, terror, and feelings of
impending doom.
• May also experience depersonalization and
derealization
Panic Disorder cont.
• Other features:
– Panic attacks may occur frequently
– May be linked specific situations if so referred to as
cued panic attacks
– Panic disorder is diagnosed as with or without
agoraphobia
• Lifetime prevalence
–
–
–
–
–
2-3% for men
5-6% for women
Typically begins in adolescence,
onset associated with stressful life experience
> 80% of patients diagnosed as having an anxiety
disorder also experience panic attacks
Etiology of Panic Disorder
Biological Theories
• Mitral valve prolapse syndrome
• Inner ear disease causes dizziness
• May be linked to “Val158Met COMT polymorphism” or
other loci within or near the COMT gene (on
chromosome 22)
Etiology of Panic Disorder (cont.)
• Noradrenergic Activity theory
– panic is caused by overactivity in the noradrenergic system
• Specifically locus ceruleus has been implicated
• stimulation of the locus ceruleus causes monkeys to have “panic attack”
• in humans yohimbine (drug that stimulates activity in the locus ceruleus) can
elicit panic attacks
• Problem in gamma-aminobutyric acid (GABA)
– GABA generally inhibit noradrenergic activity
– Positron emission tomography study found fewer GABA-receptor
binding sites in people with PD
• Cholecystokinin (CCK)
– peptide that occurs in the cerebral cortex, amygdala, hippocampus, and
brain stem, induces anxiety-like symptoms in rats and effect can be
blocked with benzodiazepines
Etiology of Panic Disorder (cont.)
• Psychological Theories
– the fear-of-fear hypothesis
• suggests that agoraphobia is not a fear of public
places per se, but a fear of having a panic attack in
public.
– misinterpretation of physiological arousal
symptoms
Therapies for Panic Disorder
• Biological Treatments
– Antidepressants
• both selective SSRIs and tricyclic antidepressants
have been used successfully to treat PD
• Psychological Treatments
– Exposure-based treatments are often useful
in reducing PD with agoraphobia
– Cognitive-Behavioural Therapy
Generalized Anxiety Disorder
• People with GAD are persistently anxious and
often about minor items.
– chronic, uncontrollable worry about everything
• Most frequent worries concern their health and
the hassles of daily life
GAD cont.
• Other features include:
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–
–
–
difficulty concentrating,
tiring easily, restlessness,
irritability,
and a high level of muscle tension
• Lifetime prevalence is 5% for the general
population
• GAD typically begins in mid-teens
• Stressful life events play role in onset
Etiology of GAD
• Psychoanalytic Perspective
– unconscious conflict between the ego and id
impulses
• Cognitive-Bahvioural Perspectives
– See learning views of phobias
• Anxiety regarded as having been classically
conditioned to external stimuli, but with a broader
range of conditioned stimuli.
Etiology of GAD cont.
Biological Perspectives
– GAD may have a genetic component.
– neurobiological model for GAD based on fact
that benzodiazepines are often effective in
treating anxiety
• receptor in the brain for benzodiazepines has been
linked to the inhibitory neurotransmitter GABA
• benzodiazepines may  anxiety by  release of
GABA
– Drugs that block or inhibit the GABA system  anxiety
Therapies for GAD
• Treatment for GAD is very similar to that
for phobias
Obsessive-Compulsive Disorder
• Obsessive-compulsive disorder (OCD)—
an anxiety disorder in which the mind is
flooded with persistent and uncontrollable
thoughts (obsessions) and the individual is
compelled to repeat certain acts again and
again (compulsions).
Obsessions vs. Compulsions
• Obsessions— intrusive and recurring thoughts,
impulses, and images
– Most frequent obsessions: fears of contamination,
fears of expressing some sexual or aggressive
impulse, and hypochondriacal fears of bodily
dysfunction
• Compulsion— a repetitive behaviour or mental
act that the person feels driven to perform to
reduce the distress caused by obsessive
thoughts or to prevent some calamity from
occurring
OCD cont.
• Other features of OCD
– Lifetime prevalence of 1 to 2%
– Affects women > than men
– Early onset is more common among men and
is associated withchecking compulsions
– Later onset is more frequent among women
and is linked with cleaning compulsions
– Depression is often co-morbid with OCD
Etiology of OCD
Psychoanalytic Theory
• Obsessions and compulsions are viewed as similar
• Result from instinctual forces, sexual or aggressive, that
are not under control because of overly harsh toilet
training
Behavioural and Cognitive Theories
• Learned behaviours reinforced by fear reduction
• Rachman’s theory of obsessions in OCD
– unwanted intrusive thoughts are the roots of obsessions
– obsessions often involve catastrophic misinterpretations of
negative intrusive thoughts
• See Table 6.4 for list of faulty cognitive appraisals
Etiology of OCD cont.
Biological Factors
• Encephalitis, head injuries, and brain tumours
associated with the development of OCD
– 2 affected areas: frontal lobes and the basal ganglia
• PET scan studies shown  activation in the frontal lobes
• Basal ganglia further linked to OCD due to link with
Tourette’s syndrome
– Tourette’s syndrome marked by motor and vocal tics
– has been linked to basal ganglia dysfunction
Etiology of OCD cont.
• hypothesized to be related to serotonin
– dopamine and acetylcholine also implicated
• Genetic evidence
– High rates of anxiety disorders occur among
the first-degree relative
– Prevalence of OCD is higher among firstdegree relatives (10.3%) than control relatives
(1.9%)
Therapies for OCD
• Psychoanalytic Therapy
– resembles that for phobias and generalized anxiety
• Exposure and Response Prevention (ERP)
– most widely used and accepted behavioural approach
– combines exposure with response prevention
• Cognitive-Behaviour Therapy
• Biological Treatment
– Drugs that increase serotonin levels
– Some tricyclics
Post-Traumatic Stress Disorder
• Extreme response to a severe stressor, including
increased anxiety, avoidance of stimuli
associated with the trauma, and a numbing of
emotional responses.
– Note. Unlike the definitions of other psychological
disorders, the definition of PTSD includes part of its
presumed etiology
PTSD cont.
• The symptoms for PTSD are grouped into three
major categories.
1.Re-experiencing the traumatic event.
2.Avoidance of stimuli associated with the event or numbing of
responsiveness.
3.Symptoms of increased arousal.
• Prevalence rate = 1 to 3%
• PTSD vs. Acute Stress Disorder
– If stressor causes significant impairment in social or
occupational functioning < than one month then acute
stress disorder is diagnosed
Risk Factors of PTSD
Risk Factors
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•
•
•
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Exposure to trauma and severity of trauma
Gender (more females)
Perceived threat to life
Personality traits of neuroticism and extroversion
Early conduct problems
Family history of psychiatric disorders
Presence of pre-existing psychiatric disorders
Early separation from parents
Previous exposure to traumas
Tendency to take personal responsibility for failures and to cope
with stress by focusing on emotions
Attachment style
Stressful occupations
Etiology of PTSD
• Psychological Theories
– PTSD arises from a classical conditioning of fear
– Anxiety sensitivity
• Biological theories
– Genetics
– Specific domains of noradrenergic system
• Trauma may raise levels of norepinephrine
• Evidence for increased sensitivity of noradrenergic receptors
in patients with PTSD
– Associated with smaller hippocampal volume
– Associated with  anterior cingulate and medial
prefrontal function
Therapies for PTSD
• Crisis intervention
• Exposure-based behaviour therapy
– exposure to thoughts and images of the frightening
event
• Systematic desensitization
• Eye Movement Desensitization and
Reprocessing
• Relaxation + rational-emotive therapy + training
in problem solving
• Psychoactive drugs
– See table 6.5
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