Mental Disorder Descriptions & Criteria
Pervasive Developmental Disorders
The Pervasive Developmental Disorders include a variety of disorders in which there is severe
and pervasive impairment in several areas of development such as social interaction skills,
communication skills or usual behavior, interests and activities. These disorders are sometimes
observed with a number of general medical conditions such as chromosomal abnormalities,
congenital infections and abnormalities of the central nervous system.
The range of manifestations of these disorders varies greatly depending on the developmental
level and age of the individual.
Disorder
Symptoms
Autistic spectrum
disorder
Markedly abnormal and impaired development in reciprocal
social interaction (i.e. incorrect use of non-verbal behaviors, lack
of interest or failure to develop peer relationships, lack of
awareness of others) and communication (i.e. delay in, lack of or
inappropriate language and conversation skills) and a
significantly restricted and repetitive repertoire of activity and
interests exhibited before a child is three years old.
Asperger's Syndrome
Severe and sustained impairment in social interaction and the
development of restricted, repetitive patterns of behavior,
interests and activities although, unlike Autistic Disorder, there
is no delay in language, cognitive development or development
of age appropriate self-help skills, adaptive behavior (other than
social interaction) and curiosity in the environment.
Attention-Deficit and Disruptive Behavior Disorders
Disorder
Symptoms
Attention-deficit /
hyperactivity disorder
A persistent pattern, present in at least two settings, of
inattention and/or hyperactivity-impulsivity that interferes with
developmentally appropriate social, academic or occupational
functioning. Some symptoms must have been present before the
age of seven years old.
Conduct disorder
A repetitive and persistent pattern of behavior in which the basic
rights of others (e.g. causing or threatening physical harm to
others including animals, property damage or loss, deceitfulness
or theft) or societal norms/rules are violated (i.e. under 13 years
of age and truanting, running away from home overnight) which
causes significant impairment in functioning. This behavior
pattern is usually present in a variety of settings.
Elimination Disorders
Disorder
Symptoms
Encopresis
Repeated passage of feces in inappropriate places (e.g. clothing
or floor) whether involuntary or intentional, at least once a
month for three months when not due to a medical condition or
use of a substance.
Enuresis
Repeated voiding of urine into bed or clothes whether
involuntary or intentional: twice a week; at least three
consecutive months or with the presence of distress or
impairment in functioning. Child needs to be at least 5 years of
age and behavior not due to a medical condition or use of a
substance.
Substance-Related Disorders
The term substance can refer to a drug of abuse, including alcohol and nicotine; medications or
toxins.
Disorder
Symptoms
Substance dependence
A pattern of repeated self-administration that results in
tolerance, withdrawal and compulsive drug-taking behavior.
Substance abuse
Recurrent substance use that causes harmful consequences.
Schizophrenia and Other Psychotic Disorders
Psychotic disorders are characterized by distortions of thinking and perception, a disorganization
of thought and behavior, cognitive impairment, disturbances in communication and social and
functional impairment.
The most common of the psychotic disorders is schizophrenia. The symptoms of schizophrenia
are grouped into two types: positive and negative. Positive symptoms include hallucinations,
delusions, disorganized speech and motor manifestations such as grossly disorganized behavior
or catatonia. Negative symptoms include avolition, flat affect, alogia and anhedonia.
Disorder
Symptoms
Schizophrenia
A mixture of positive and negative symptoms most of the time
for at least one month (shorter if successfully treated), with some
signs of the disorder for at least six months. These signs and
symptoms are associated with a marked decline in social or
occupational functioning.
Schizophreniform
disorder
Characterized by a symptomatic presentation that is equivalent
to schizophrenia except that its duration is limited to less than
six months and there is not always a decline in social or
occupational functioning.
Schizoaffective disorder
A disturbance involving acute symptoms of schizophrenia
alongside a mood episode (depression, mania or a mixture of the
two). This disorder may thus be divided into two types: bipolar
(mania or mixed episode) and unipolar (depressive episode).
Delusional disorder
Characterized by at least a month of non-bizarre delusions.
There is a relative absence of hallucinations or other positive
symptoms of schizophrenia.
Brief psychotic disorder
When positive psychotic symptoms are present for less than a
month.
Mood Disorders
Mood disorders involve 'episodes' of dysfunction although episodes themselves are not
diagnosable mental illnesses.
Episodes
Symptoms
Major depressive episode
Involves at least a two week period in which the person
regularly experiences some of the following: a depressed mood,
loss of interest or enjoyment in activities, change in weight and
appetite, sleeping problems, fatigue, feelings of worthlessness or
inappropriate guilt, difficulty concentrating and/or recurrent
suicidal ideation, attempts or plans.
Manic episode
Involves at least one week of abnormally or persistently
elevated, expansive or irritable mood where the person
experiences some of the following: inflated self-esteem,
decreased need for sleep, increased talkativeness, distractibility
and/or agitation, racing thoughts and/or excessive involvement
in pleasurable activities that have a high potential for painful
consequences (such as buying sprees, sexual indiscretions).
Mixed episode
In a mixed episode, criteria for both a manic episode and major
depressive episode are met for at least one week.
Hypomanic episode
A hypomanic episode is the same as a manic episode but can be
noted after four days; it need not be so severe as to cause
impairment in social or occupational functioning.
Disorder
Symptoms
Major depressive disorder
Characterized by one or more major depressive episode(s).
Dysthymic disorder
A milder, more persistent form of depression which is diagnosed
after the person has experienced symptoms for at least two
years. It cannot be diagnosed if any episodes have occurred.
Bipolar I disorder
Characterized by one or more manic or mixed episodes. Often
the individual has also had one or more major depressive
episodes.
Bipolar II disorder
Characterized by one or more major depressive episodes with at
least one hypomanic episode. The presence of symptoms that
meet manic or mixed episode criteria precludes diagnosis of this
disorder.
Cyclothymic disorder
A chronic (at least two years) fluctuating mood disturbance
involving numerous periods of hypomanic and depressive
symptoms. The presence of symptoms that meet major
depressive, manic or mixed episode criteria precludes diagnosis
of this disorder.
Anxiety Disorders
Common to most anxiety disorders are: panic symptoms or 'attacks' with symptoms such as
shortness of breath, hyperventilation, heart palpitations or chest tightness, light-headedness,
sweating, shaking, nausea and/or vomiting; fearfulness, distress, agitation, restlessness and/or
sleep disturbance.
Disorder
Generalized anxiety
disorder
Symptoms
Excessive anxiety or worry felt for at least six months that is
difficult to control and focuses on a number of events or
activities. Symptoms include feeling restless, fatigue, difficulty
concentrating, irritability, muscle tension and sleeping problems.
Obsessive compulsive
disorder (OCD)
OCD is made up of either (or sometimes both) obsessions or
compulsions. Obsessions are recurrent, persistent, intrusive and
inappropriate thoughts, impulses or images. Compulsions are
repetitive behaviors acted out in response to an obsession. The
person recognizes that their obsessions and/or compulsions are
excessive, cause distress or anxiety, are time-consuming or
interfere with the person's normal routine.
Panic disorder (with or
without agoraphobia)
This involves the person having unexpected panic attacks
followed by persistent concern or worry about having another
attack and about the implications of having another attack. As a
result, the person changes their behavior in relation to the
attacks. Panic disorder is sometimes accompanied by
agoraphobia, which involves having anxiety about being in
places or situations from which escape might be difficult or
embarrassing or in which help may not be available. Symptoms
involve the person either avoiding such situations, or enduring
them and suffering considerable distress or anxiety as a result, or
needing a companion in such situations.
Social phobia
Social phobia involves a marked and persistent fear of social or
performance situations, of exposure to unfamiliar people, or of
possible scrutiny by others, or fear of acting in a way that will be
humiliating or embarrassing. Exposure to these things causes
anxiety and/or panic attacks, so the person usually avoids the
situations.
Specific phobia
This phobia is related to marked, persistent and excessive fear of
a specific object or situation, causing immediate anxiety and/or
panic attacks. Phobic cues may include animals; blood, injury or
injections; situations involving the natural environment (such as
heights or storms); or other specific situations such as airplanes,
lifts or enclosed spaces.
Post-traumatic stress
disorder (PTSD)
PTSD results from the person having experienced a traumatic
event where they perceived themselves (or others) to be in
danger of loss of life or physical integrity, and thus felt intense
fear, helplessness and/ or horror. Following the event, for at least
one month, the person re-experiences the event in ways (such as
dreams or recollections) that increase arousal (causing sleep
problems, anxiety, anger, difficulty concentrating and/or
hypervigilance, for example). The person thus avoids situations
reminding them of the event, or may become numb.
Acute stress disorder
This disorder is similar to PTSD but lasts for less than a month.
Somatoform Disorders
These disorders feature the presence of non-intentional physical symptoms that suggest a general
medical condition although they are not fully explained by a general medical condition, effects
of a substance or another mental disorder. The symptoms cause significant distress or
impairment in functioning.
Disorder
Symptoms
Somatisation disorder
A combination of pain, gastrointestinal, sexual and pseudo
neurological symptoms that appear before the age of 30 years
and extend over a period of years.
Conversion disorder
Symptoms or deficits affecting motor or sensory function in
which psychological factors are associated.
Pain disorder
Pain that has psychological factors that play an important role in
its onset, severity, exacerbation or maintenance.
Hypochondriasis
The preoccupation with fear or the idea of having a serious
disease, based on a misinterpretation of bodily symptoms or
functions.
Body dysmorphic
disorder
The preoccupation with an imagined or exaggerated defect in
physical appearance.
Dissociative Disorders
Disorders involve a disruption in the usually integrated functions of consciousness, memory,
identity or perception of the environment.
Disorder
Symptoms
Dissociative amnesia
An inability to recall important personal information, often of a
traumatic or stressful nature.
Dissociative fugue
Sudden, unexpected travel away from home or work along with
an inability to recall one's past and confusion about personal
identity or assumption of a new identity.
Dissociative identity
disorder (formerly
multiple personality
disorder)
The presence of two or more distinct identities or personality
states that recurrently take control of the person's behavior along
with an inability to recall important personal information.
Eating Disorders
Disorder
Symptoms
Anorexia nervosa
A refusal to maintain a normal body weight, an intense fear of
gaining weight and a significant disturbance in the person's
perception of his or her body's size or shape.
Bulimia nervosa
Repeated episodes of binge eating followed by compensatory
behaviors such as vomiting, use of laxatives or diuretics, fasting
or excessive exercise.
Adjustment Disorder
Disorder
Adjustment disorder
Symptoms
Emotional or behavioral symptoms such as marked distress or
significant impairment in normal functioning which develop
within three months in response to an identifiable psychosocial
stressor and do not meet the criteria for another disorder nor due
to bereavement (reaction to the death of a loved one).
Note: All disorders are summarized from the American Psychiatric Association (APA) (2000).
Diagnostic and Statistical Manual of Mental Disorders (4th ed) (DSM-IV-TR). Washington DC:
APA. FAMILY