Chapter 14: Psychological Disorders
Abnormal Behaviour: Myths, Realities, and Controversies
1.The Medical Model Applied to Abnormal Behaviour:
medical model - proposes that it’s useful to think of abnormal behaviour as a disease.
• prior to the 18th century,most conceptions of abnormal behaviour were based on superstition.
• with the rise of the medical model, victims of a mental illness were viewed with more sympathy and less hatred and fear.
diagnosis - distinguishing one illness from another.
etiology - the apparent causation and developmental history of an illness.
prognosis - a forecast about the probable course of an illness.
2. Criteria of Abnormal Behaviour:
in making diagnoses, clinicians rely on a variety of criteria, such as:
1. Deviance: people are often said to have a disorder because their behaviour deviates from what their society
2. Maladaptive behaviour: people are judged to have a psychological disorder because their everyday adaptive
behaviour is impaired(drug disorders).
3. Personal distress: the diagnosis of a psychological disorder is often based on an individual’s report of great
• people are often viewed as disordered when only one criterion is met
• judgements about mental illness reﬂect prevailing cultural values, social trends, and political forces, as well as scientiﬁc
• people are judged to have psychological disorders only when their behaviour becomes extremely deviant,maladaptive, or
3.Stereotypes of Psychological Disorders:
• 3 stereotypes of psychological disorders that are largely inaccurate include:
1. Psychological disorders are incurable: the vast majority of people who are diagnosed as mentally ill eventually
improve and lead normal lives.
2. People with psychological disorders are often violent and dangerous: this stereotype exist because incidents of
violence involving the mentally ill tend to command media attention. 3. People with psychological disorders behave in bizarre ways and are very diﬀerent from normal people: this is
true in a small minority of cases, usually involving relatively severe disorders.
4. Psychodiagnosis: The Classiﬁcation of Disorders:
• the publication of APA’s Diagnostic and Statistical Manual of Mental Disorders(DSM)-III in 1980 introduced a new
multiaxial system of classiﬁcaltion, which asks for judgements about individuals on 5 separate dimensions,or “axes.”
✴ See the Overview of the DSM diagnostic system Table
5.The Prevalence of Psychological Disorders:
epidemiology - the study of the distribution of mental of physical disorders in a population.
prevalence - refers to the percentage of a population that exhibits a disorder during a speciﬁed time period.
• about 1/5 of the population exhibit clear signs of mental illness at some point of their lives.
• the most recent large-scale epidemiological study estimated the lifetime risk of a psychiatric disorder to be 51% (2005).
anxiety disorders - a class of disorders marked by feelings of excessive apprehension and anxiety.
1.Generalized Anxiety Disorders:
generalized anxiety disorder - marked by a chronic,high level of anxiety that is not tied to any speciﬁc threat.
• sometimes called free-ﬂoating anxiety because it’s nonspeciﬁc
• people with this disorder worry constantly about yesterday’s mistakes and tomorrow’s problems
• they often dread decisions and brood over them endlessly
• it is often accompanied by physical symptoms such as trembling,muscle tension,diarrhea,dizziness,
faintness,sweating,and heart palpitations.
• more frequent in females than males
2. Phobic Disorder:
phobic disorder - marked by a persistent and irrational fear of an object or situation that presents no realistic danger
• mild phobias are common,however,people are said to have a phobic disorder only when their fears seriously interfere
with their everyday behaviour.
• phobic reactions tend to be accompanied by physical symptoms of anxiety,such as trembling and palpitations
• people can develop a phobic responses to almost anything,however certain types of phobias are more common -
acrophobia(fear of heights),claustrophobia(fear of small,enclosed places),brontophobia(fear of
storms),hydrophobia(fear of water),and various animal and insect phobias.
• even imagining a phobic object and situation can trigger great anxiety 3.Panic Disorder and Agoraphobia:obse
panic disorder - characterized by recurrent attacks of overwhelming anxiety that usually occur suddenly and
• these paralyzing panic attacks are accompanied by physical symptoms of anxiety.
• the concern about exhibiting panic in public may escalate to the point where they are afraid to leave home, which leads
to a condition called agoraphobia.
agoraphobia - a fear of going out to public places,
• some people might venture out if accompanied by a trusted companion
• agoraphobia is not longer viewed as a phobic disorder, but as a complication of panic disorder
• about 2/3 of the people who suﬀer panic disorder are female
4. Obsessive - Compulsive Disorder:
• obsessions are thoughts that repeatedly intrude on one’s consciousness in a distressing way.
• compulsions are actions that one feels forced to carry out.
obsessive - compulsive disorder (OCD) - marked by persistent,uncontrollable intrusions of unwanted
thoughts(obsessions) and urges to engage in senseless rituals(compulsions).
obsessions sometimes centre on inﬂicting harm on others,personal failures,suicide,or sexual acts
• people troubled by obsessions may feel that they have lost control of their mind.
• speciﬁc types of obsessions tend to be associated with speciﬁc types of compulsions(ex. obsessions of contamination
tend to be paired with cleaning compulsions)
5.Post - Traumatic Stress Disorder (PTSD):
• PTSD is often elicited by any of a variety of traumatic events
• in some cases, PTSD does not surface until many months or years after a person’s exposure to severe stress
• it’s more common in women
• common symptoms include re-experiencing the traumatic event in the form of nightmares or ﬂashbacks, emotional
numbing,alienation,problems in social relationships,and increased sense of vulnerability, and elevated levels of
• increased vulnerability is associated with greater personal injuries and losses,greater intensity of exposure to the
traumatic event,and more exposure to the grotesque aftermath of the event
6. Etiology of Anxiety Disorders:
a) Biological Factors: concordance rate - indicates the percentage of twin pairs or other pairs of relatives who exhibit the same disorder.
• the results of both twin studies and family studies suggest that there is a moderate genetic predisposition to anxiety
• scientists are beginning to unravel the neurochemical bases for anxiety disorders:
disturbances in the neural circuits using GABA may play a role in some types of anxiety disorders
• abnormalities in neural circuits using serotonin have recently been implicated in panic and OCD disorders
b) Conditioning and Learning:
• many anxiety responses can be acquired through classical conditioning and maintained through operant conditioning.
• an originally neutral stimulus may be paired with a frightening event so that it becomes a conditioned stimulus eliciting
• once the fear is acquired through classical conditioning,the person may start avoiding the anxiety-producing stimulus.
The avoidance response is negatively reinforced because it is followed by a conditioning
• Martin Seligman’s concept of preparedness suggests that people are biologically prepared by their evolutionary history
to acquire some fears much more easily than others(ex. ancient resources of threat such as snakes and spiders).
• conditional fears can be created through observational learning as well
c) Cognitive Factors:
maintain that certain styles of thinking make some people particularly vulnerable to anxiety disorders
• according to this view,some people are more likely to suﬀer from problems with anxiety because they tend to:
a. misinterpret harmless situations as threatening
b. focus excessive attention on perceived threats
c. selectively recall information that seems threatening
• studies have supported that anxiety disorders are stress-related
• high stress often helps to precipitate the onset of anxiety disorders
somatoform disorders - physical ailments that cannot be fully explained by organic conditions and are largely due to
somatization disorder - marked by a history of diverse physical complaints that appear to be psychological in origin. • occurs mostly in women and often coexist with depression and anxiety disorders
• victims report an endless succession of minor physical ailments that seem to wax and wane in response to the stress in
• the distinguishing feature of this disorder is the diversity of the victims’ physical complaints.
over the years they report a mixed bag of cardiovascular,gastrointestinal,pulmonary,neurological,and genitourinary
• somatization patients are very resistant to the suggestion that their symptoms might be the result of psychological
2. Conversion Disorder:
conversion disorder - characterized by a signiﬁcant loss of physical function(with no apparent organic basis),usually in a
single organ system.
• common symptoms include partial or complete loss of vision,partial or complete loss of hearing,partial paralysis,severe
laryngitis or mutism,and loss of feeling or function in limbs.
• in some cases, telltale clues reveal the psychological origins of the illness because the patient’s symptoms are not
consistent with medical knowledge about their apparent case.
• Ex. it’s impossible that a loss of feeling in the hand exclusively since the nerve distribution patters are known to
cover the whole arm.
tend to have an acute onset triggered by stress
hypochondriasis(hypochondria) - characterized by excessive preoccupation with health concerns and incessant worry
about developing physical illnesses.
• when hypochondriacs are assured by a physician that they do not have any real illness, they often are skeptical
• hypochondriacs don’t subjectively suﬀer from physical distress as much as they overinterpret every conceivable sign of
• hypochondria frequently appears alongside other psychological disorders,especially anxiety disorders and depression.
4. Etiology of Somatoform Disorders:
inherited aspects of physiological functioning, such as a highly reactive autonomic nervous system,may predispose some
people to somatoform disorders.
• the available evidence suggests that these disorders are largely a function of personality and cognitive factors
a) Personality Factors:
• people with histrionic personality characteristics tend to be self-centered,suggestible,excitable,highly emotional,and
• such people thrive on the attention that they get when they become ill b) Cognitive Factors:
• some people focus excessive attention on their internal physiological processes and amplify normal bodily sensations
into symptoms of distress,which lead them to pursue unnecessary medical treatment.
tend to draw catastrophic conclusions about minor bodily complaints
c) The Sick Role:
• some people grow fond of the role associated with being sick
• one payoﬀ is that becoming ill is a superb way to avoid having to confront life’s challenges
• another beneﬁt is that physical problems can provide a convenient excuse when people fail,or worry about failing, in
endeavours that are critical for their self-esteem.
• the sympathy that illness often brings may straighten a person’s tendency to feel ill.
dissociative disorders - a class of disorders in which people lose contact with portions of their consciousness or memory,
resulting in disruptions in their sense of identity.
1.Dissociative Amnesia and Fugue:
dissociative amnesia - a sudden loss of memory of important personal information that is too extensive to be due to
• memory losses may occur for a single traumatic event or for an extended period of time surrounding the event.
dissociative fugue - people lose their memory of their entire lives, along with their sense of personal identity.
• they can forget their name, where they live, however,they remember matters unrelated to their identity, such as how to
drive a car or how to do math.
2. Dissociative Identity Disorder:
dissociative identity disorder (DID) - involves the coexistence in one person of two or more largely complete, and
usually very diﬀerent, personalities.
known as multiple personality disoder
• people with “multiple personalities” feel that they have more than one identity
• each personality has his or her own name,memories,traits,and physical mannerisms.
• in this disorder,the various personalities are often unaware of each other
• transitions between identities often occur suddenly
• diﬀerent personalities may assert that they are diﬀerent in age,race,gender,and sexual orientation
• most DID patients also have a history of anxiety or mood or personality disorders 3.Etiology of Dissociative Disorders:
• psychogenic amnesia and fugue are usually attributed to excessive stress
• some researchers say that certain personality traits - fantasy proneness and a tendency to become intensely absorbed in
personal experiences - may make some people more susceptible to dissociative disorders.
• other researchers maintain that most cases of DID are rooted in severe emotional trauma that occurred during
childhood, such as rejection from parents and physical/sexual abuse.
• tend to be episodic, and the episodes of disturbance can vary in length, but they typically last 3-12 months
mood disorders - a class of disorders marked by emotional disturbances of varied kinds that may spill over to disrupt
physical,perceptual,social,and thought processes.
1.Major Depressive Disorder:
major depressive disorder - when people show persistent feelings of sadness and despair and a loss of interest in
previous sources of pleasure.
Characteristics Manic Episode Depressive Episode
Emotional Elated,euphoric,very sociable,impatient at any Gloomy,hopeless,socially withdrawn,irritable
Cognitive Characterized by racing thoughts,ﬂight of Characterized by slowness of thought
ideas,desire for action,and impulsive behaviour;processes,obsessive worrying,inability to make
talkative,self-conﬁdent, experiencing delusions decisions,negative self-image,self-blame,and
of grandeur delusions of guilt and disease
Motor Hyperactive,tireless,requiring less sleep than Less active,tired,experiencing difﬁculty in
usual,showing increased sex drive and sleeping,showing decreased sex drive and
ﬂuctuating appetite decreased appetite
• majority of cases emerge before age 40
dysthymic disorder - consists of chronic depression that is insuﬃcient in severity to justify diagnosis of a major
• the prevalence of depression is about twice as high as in women as it is in men, although in childhood,the frequency of
depression is the same for both girls and boys.
• some researchers believe that women experince more depression than men because they experience greater stress and
adversity; also women have a greater tendency to ruminate about setback and problems,which elevates the vulnerability
2. Bipolar Disorder: bipolar disorder - characterized by the experience of one or more manic episodes as well as periods of depression.
• in a manic episode:
•a person’s mood becomes elevated to the point of euphoria
self-esteem often skyrockets as the person bubbles over with optimism,energy,and extravagant plans
•he/she becomes hyperactive and may go for days without sleep
•talks rapidly and changes topics wildly,as his/her mind races at breakneck speed
•judgement is impaired
cyclothymic disorder - when people exhibit chronic but relatively mild symptoms of bipolar disturbance.
• in their milder forms, manic states can seem attractive as the person’s energy,self-esteem, and optimism increases
• manic episodes often have a paradoxical negative undercurrent of irritability and depression
• mild manic episodes usually escalate to higher levels that become scary and disturbing
• bipolar disorder is seen equally in men and women
• about 20% of bipolar patients exhibit a rapid - cycling pattern,which means they go through 4 or more manic or
depressive episodes within a year.
3.Diversity in Mood Disorders:
• the nature of symptoms and course of illness may diﬀer somewhat from person to person
seasonal aﬀective disorder(SAD) - a type of depression that follows a seasonal pattern
•symptoms may show a regular relationship with the seasons of the year (most common is winter depression)
•there are suggestions that the onset of SAD is related to melatonin production and circadian rhythms
•one form of treatment for SAD is phototherapy
postpartum depression - a type of depression that sometimes occurs after childbirth
•symptoms can include both depression and mania
•occurs within 4 weeks of childbirth
•research shows that previous episodes of depression,stress,and adjustment problems are risk factors
4. Mood Disorders and Suicide:
• one of the three leading causes of death of people b/w the ages 15 and 34
• suicide rates diﬀer across various groupings, including gender,age,and rural/urban residence.
evidence suggests that women attempt suicide 3 times more often than men,but men complete 4 times as many suicide
• both bipolar disorder and depression are associated with dramatic elevations in suicidal rates
5.Etiology of Mood Disorders:
a) Genetic Vulnerability:
• heredity can create a predisposition to mood disorders • twin studies show that concordance rates average around 65% for identical twins,but only 14% for fraternal twins
• environmental factors probably determine whether this predisposition is converted into an actual disorder
• the inﬂuence of genetic factors appears to be stronger for bipolar disorders than for unipolar disorders
b) Biological and Neurochemical Factors:
• correlations have been found b/w mood disorders and abnormal levels of norepinephrine and serotonin,although other
neurotransmitter disturbances may also contribute
• drug therapies that aﬀect the availability of the neurotransmitters are fairly eﬀective in the treatment of mood disorders
• studies have found correlations b/w mood disorders and a variety of structural