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Anxiety Disorders
Importance of Anxiety Disorders
 Associated with considerable suffering and impaired
functioning
 Some anxiety sufferers are housebound; many are unable to
work
 Prevalence
 Among the most common psychiatric disorders
 1 year prevalence: 12-17% (one or more anx disorder)
 Leading cause for seeking mental health services
 Total economic costs
(% of psychiatric health care budget)
 Anxiety disorders (32%)
> mood disorders (22%)
> schizophrenia (21%)
Approaches to Classification
lumpers vs. splitters
DSM-III began the process of “splitting” the
anxiety disorders into many smaller
categories
Fundamental Features of Anxiety Disorders
 Unwanted emotions
 panic attacks
 chronic anxiety
 excessive fear
 Unwanted thoughts
 obsessions
 excessive worries
 intrusive recollections
 Unwanted actions
 avoidance, escape, distraction
 compulsions
Major Anxiety Disorders in DSM-IV
Panic disorder
Agoraphobia
Specific phobia
Social phobia (social anxiety disorder)
Generalized anxiety disorder
Obsessive-compulsive disorder
Posttraumatic stress disorder
Acute stress disorder
DSM-IV Criteria for Panic Disorder
 recurrent unexpected panic attacks
 at least 1 attack followed by at least a month of 1 or
more of the following:
persistent concern about having additional panic
attacks
worry about implications of the attack
significant change in behaviour related to the attacks
Panic Attack: Defining Features
Discrete period of intense fear or discomfort:
abrupt onset
peaks within 10 min
peak intensity lasts an average of 20 min
can occur during waking hours or during sleep
four or more symptoms required to define a DSMIV panic attack
attacks with fewer than four symptoms are called
“limited symptom” panic attacks
Panic Attack Symptoms
 Palpitations
 Sweating
 Trembling or shaking
 Dyspnea
 Choking sensations
 Chest pain or discomfort
 Nausea or GI distress
 Chills or hot flushes
 Paresthesias (numbness
or tingling)
 Dizziness or faintness
 Derealization or
depersonalization
 Fear of losing control or
going crazy
 Fear of dying
DSM-IV Criteria for Agoraphobia
 anxiety about being in places or situations from
which escape might be difficult
 or in which help may not be available if panic attacks
or panic-like symptoms occur
 the agoraphobic situations are avoided (e.g., travel is
restricted) or else endured with marked distress
Agoraphobia: Situations Commonly
Feared and Avoided
Travelling
Being far from home
Enclosed spaces
Wide open spaces
Supermarket line-ups
High places
Being alone
Specific Phobia
 Severe, excessive, and persistent fear
 Exposure to phobic object evokes fear or panic
 Person typically avoids phobic object
 Recognizes the fear is unreasonable
 Subtypes:
animals
natural environment stimuli (e.g., heights, water)
situations (e.g., enclosed spaces)
blood-injection-injury
other
Social Phobia
 same basic criteria as specific phobia
 social or performance situations in which the person
is exposed to unfamiliar people or to possible scrutiny
by others
 person fears acting in a way that will be humiliating
or embarrassing
Social Phobia: Examples of Feared Situations
 giving a speech
 musical performances
playing a musical instrument
singing
 one-to-one conversations
authority figures
people of the opposite sex
 eating in a restaurant
 urinating in a public restroom
Generalized Anxiety Disorder
 excessive anxiety and worry
occurring on most days
for at least 6 months
 person worries about a number of events or activities
 person finds it difficult to control worry
Obsessive-Compulsive Disorder
 Either obsessions or compulsions
 Obsessions
recurrent, persistent thoughts, impulses, or images
intrusive, unwanted
distressing
not simply excessive worries
 Compulsions
repetitive behaviours or mental acts
aimed at reducing distress or preventing harm
often in response to obsessions
Examples of Obsessions
violent impulses and images
sexual thoughts
blasphemous thoughts
Examples of Compulsions
compulsive cleaning
compulsive checking
hoarding of possessions
ordering and arranging objects
Traumatic Stress Disorders
Posttraumatic stress disorder
Acute stress disorder
Discussed in the following lecture
Lifetime Prevalence (%)
Panic disorder
Agoraphobia
Specific phobia
Social phobia
Posttraumatic stress disorder
Acute stress disorder
Obsessive-compulsive disorder
Generalized anxiety disorder
1-2
1-2
7-11
3-13
8
14-33*
2.5
5
* Among people exposed to traumatic events
Untreated Course of Anxiety Disorders
 Often arise in the context of stressful life events
 Typically chronic, but some remit without treatment
 Severity tends to wax and wane, often in response to life
stressors
 For a given disorder, different symptoms can follow
different courses; e.g.,
panic attacks may decrease in frequency as
agoraphobia becomes more severe
obsessions may decrease in frequency as compulsions
becomes more severe
Gender Differences and Age of Onset
Most anxiety disorders: Gender ratio (F:M)
ranges from 2:1 to 3:1
OCD: no gender differences
Age of onset
varies with disorder
varies with exposure to stressors
trends:
many anxiety disorders arise in adolescence
phobias often arise in childhood
Comorbidity
 Current vs. lifetime comorbidity
 Anxiety disorders are often comorbid with
one another
mood disorders
substance-use disorders
eating disorders
personality disorders
 Why are anxiety disorders so often comorbid with other
disorders?
Relation Between Anxiety and Depression
 both defined in terms of negative emotional experience
 both triggered by stressful experiences
 both respond to similar treatment methods (SSRIs,
cognitive-behaviour therapy)
Clark and Watson’s Model of Anxiety
and Depression
 two dimensions of mood: positive and negative affect
 negative affect:
high = upset; low = relaxed
descriptive adjectives such as angry, guilty, afraid,
sad, disgusted, or worried
 positive affect:
high = energetic; low = tired
descriptive adjectives such as delighted,
interested, enthusiastic, proud
Clark and Watson’s Model of Anxiety
and Depression
 general distress: depressed people and anxious
people both experience high levels of negative affect
 they are distinguished on the basis of positive affect
 depressed people are low on positive affect (e.g., loss
of interest; fatigue; anhedonia)
 anxious people also experience high levels of
physiological arousal
Clark and Watson’s Model
High negative affect
Low positive affect
High positive affect
Low negative affect
Environmental and Genetic Factors in
Anxiety Disorders
Anxiety disorders appear to arise from
combination of:
disorder
disorder
disorder
disorder
specific genetic factors
specific environmental factors
non-specific genetic factors
specific environmental factors
Genetic factors appear to influence the sorts of
environment a person chooses
e.g., genes for sensation-seeking --> exposure to
traumatic events
Role of Life Events in Anxiety and
Depression
people with anxiety disorders have
experienced more stressful life events
DANGER EVENTS: lead to anxiety
LOSS EVENTS: lead to depression
Role of Learning
Conditioned fear reactions
classical (Pavlovian) conditioning
operant conditioning (e.g., avoidance learning)
role in PTSD, phobias
Maladaptive beliefs
different mechanism to Pavlovian conditioning?
prominent role in panic disorder
appear to play a role in other anxiety disorders
Classical Conditioning (Pavlov)
 UCS (meat powder) --> UCR (salivation)
 CS (ringing a bell) --> CR (salivation)
 original version: any neutral stimulus can be paired
with the UCS and eventually lead to the CR
 the case of Little Albert
Preparedness Version of Learning Theory
 problems with traditional theory
 conditioned fear responses are easy to extinguish
 phobias that develop after trauma are usually learned
in only one trial (not in labs)
 why are phobias only associated with certain kinds of
stimuli?
Preparedness Theory of Phobias
 organisms are biologically prepared to learn certain
kinds of associations quickly
 biological constraints on learning
 cannot use simply any neutral stimulus as the CS in
classical conditioning
 organism’s “wiring” shaped by evolutionary pressures
 prepared associations are learned in one trial and are
very difficult to extinguish
Clark’s Cognitive Model of Panic Attacks
Trigger Stimulus
(internal or external)
Perceived Threat
Interpretation of
Sensations as
Catastrophic
Apprehension
Body
Sensations
Trigger Stimulus: Internal or External
(Dizziness caused by standing up quickly)
Perceived Threat
(‘I could pass out’)
Catastrophic
Misinterpretations
Anxiety or Panicky
Feelings
(‘Something really bad is
happening; I could die’)
Sensations
(Palpitations, stronger
dizziness)
Examples of Links Between
Sensations and Misinterpretations
Sensation
Catastrophic misinterpretation
Palpitations
“I am having a heart attack”
Depersonalization “I am going insane”
Shortness of breath “I am suffocating”
Numbness and
tingling
“My nervous system is
collapsing”
People with panic disorder can catastrophically
misinterpret all sorts of stimuli, including visual illusions
How does the Cognitive Model Explain
Unexpected Panic Attacks?
Trigger Stimulus
(internal or external)
Perceived Threat
Interpretation of
Sensations as
Catastrophic
Apprehension
Body
Sensations
Empirically Supported Treatments for
Anxiety Disorders
 Drug therapies
SSRIs: e.g., Prozac
High potency benzodiazepines: e.g., Xanax
 Cognitive-behavioural therapies
exposure therapy
cognitive restructuring
 Important considerations
Patient preference
High addiction potential for some drugs (e.g.,
Xanax)
Relapse rates: higher for drugs than for CBT
Cognitive Symptoms in
Anxiety Disorders (Beck)
Sensory-Perceptual
“Mind”: hazy, cloudy, foggy, dazed.
Self-conscious
Hypervigilant
Thinking Difficulties
 Can’t recall important things
Confused
Unable to control thinking
Cognitive Symptoms in
Anxiety Disorders (Beck)
Conceptual
Cognitive distortions
Fear of losing control
Fear of negative evaluations