Description of Mental Illnesses

Please click on the links below to jump to any particular illness.

Affective Disorders (Bipolar Disorder and Depression)
Anxiety Disorders (including Obsessive Compulsive Disorder)
Eating Disorders
Personality Disorders
Schizoaffective Disorder

For more mental health links, please consult our External Resource List.
Please note that we provide these descriptions for information purposes only. This information should not be used to diagnose an illness. Consult a medical professional if you have any questions or concerns.


Affective Disorders (Bipolar Disorder and Depression)

Affective or mood disorder is the term given to a group of diagnoses where the essential characteristic is a disturbance in mood. This group of diagnoses includes depressive disorders and bipolar disorder (formerly known as manic depression), which are differentiated based on the occurrence of a manic or hypomanic episode. Approximately 8% of adults will experience major depression at some time in their lives, and approximately 1% will have bipolar disorder. Individuals with mood disorders often suffer distress or impairment in social, occupational, educational or other important areas of functioning.

During a depressive episode, an individual may experience:
· Feelings of sadness, emptiness, or hopelessness
· Loss of interest or pleasure (including hobbies, daily activities or sexual desire)
· Change in appetite
· Sleep disturbances
· Decreased energy or fatigue
· Thoughts of suicide
· Sense of worthlessness or guilt
· Difficulty concentrating or making decisions
· Extreme irritability

Major depressive disorder (also known as MDD, clinical depression, or major depression) is characterized by the presence of at least one major depressive episode (at least 2 weeks of depressed mood or loss of interest in usual activities every day accompanied by at least four additional symptoms of depression). MDD is a recurrent illness with frequent relapses and recurrences.

Major depression should not be confused with Adjustment disorder (also referred to as reactive or situational depression, or situational affective disorder), a temporary condition triggered by life events or stressors, where individuals experience symptoms similar to those present in depression. Should the condition persist long after the stressor or its consequences have terminated, the affected individual should consult a doctor.

Dysthymic disorder consists of a chronically depressed mood that occurs for most of the day for more days than not over a period of at least two years, without long, symptom-free periods. The symptoms are less severe than those seen in Major Depressive Disorder but they last longer. Individuals with dysthymic disorder report feeling a lack of productivity and a difficulty to enjoy activities and have fun. As a result of its prolonged nature, dysthymia can be very debilitating. Individuals with this disorder are also at high risk of experiencing an episode of major depression.

Major Depressive Disorder with Seasonal Pattern Specifier (Previously Seasonal Affective Disorder): In the DSM-IV and DSM-5, Seasonal Affective Disorder (SAD) is no longer classified as a unique mood disorder, but as a specifier for recurrent major depressive disorder called “with seasonal pattern”. People experience depressive symptoms only at specific times of the year, most commonly during the winter months, where this might be casually referred to as the “winter blues”.

For a diagnosis of MDD with Seasonal Pattern Specifier, patients must meet four criteria:
· Depressive episodes at a particular time of the year
· Remissions of mania/hypomania at a particular time of the year
· Patterns must have lasted two years with no nonseasonal major depressive episodes during that same period
· Seasonal episodes must outnumber other depressive episodes throughout the patient’s lifetime

Some common treatments for winter-based seasonal affective disorder are light therapy, antidepressant medication, cognitive-behavioural therapy, and supplementation of the hormone melatonin.

Postpartum Depression: Often referred to as the “baby blues,” postpartum depression is a form of major depression where onset of a major depressive episode occurs within 4 weeks of delivery.

Along with the symptoms of depression, mothers may also experience:
· Lack of interest in the baby, family or friends
· Fear of being a bad mother
· Fear that harm will come to the baby
· Thoughts of harming the baby or herself

For more information on depression:
Depression in Women
Depression in Men
Postpartum Depression
Depression Hurts

Bipolar Disorder is characterized by episodes of mania, typically alternating with episodes of depression.

When experiencing a manic episode, the following symptoms may be present:
· Excessively high or elated mood
· Boundless energy, enthusiasm and need for activity
· Hyperactivity or racing thoughts, short attention span
· Rapid, loud, disorganized speech
· Decreased sleep
· Irritability, rapid shifts to rage or sadness
· Short temper and argumentativeness
· Unreasonable optimism, poor judgement or delusional thinking, sometimes leading to involvement in activities that have painful consequences such as shopping sprees or unwise business investments.

Individuals with bipolar disorder may also have episodes of hypomania (a lower level of mania where the individual may still be highly functioning), mixed states (features of mania and depression occur simultaneously), and in some cases rapid cycling (at least four major depressive, manic, hypomanic or mixed episodes in a year) or psychosis.

Cyclothymic disorder is a mood disorder in which an individual experiences ups and downs like those experienced in bipolar disorder but are not as severe. Nonetheless, it is still important to seek help because if left alone your chances of having bipolar I and II are increased.

AMI-Quebec offers support groups for family, friends, and people living with Bipolar Disorder and Depression. Click HERE for more information.

For more information on depression and bipolar disorder:
Depression and Bipolar Support Alliance
The Organization for Bipolar Affective Disorder

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Anxiety Disorders

Anxiety disorders affect approximately 12 percent of Canadians each year and, as a group, represent the most common of all mental illnesses. Individuals with anxiety disorders experience excessive and unrealistic feelings of fear, worry, anxiety or distress that interfere with their lives and functioning. These feelings may cause them to avoid situations that trigger anxiety or to develop compulsive rituals that lessen the anxiety.

Generalized Anxiety Disorder (GAD): Excessive, uncontrollable and often irrational worry about everyday things that is disproportionate to the actual source of worry. Individuals suffering from GAD often anticipate disaster and are overly concerned about everyday matters. Many different physical symptoms may also occur, including fatigue, sweating and headaches. For diagnosis of this disorder, symptoms must be ongoing and persist at least 6 months.

Obsessive-Compulsive Disorder: An anxiety disorder causing people to be constantly troubled by persistent ideas, thoughts or impulses (obsessions) that drive them to carry out repetitive behaviours or mental acts (compulsions). OCD sufferers generally recognize their obsessions and compulsions as senseless, but are unable to ignore them. The onset of OCD is typically before age 25 and often occurs in childhood or adolescence. One-sixth of the population shows mild obsessive symptoms, and almost 2% of Canadians will suffer from OCD each year.

Common obsessions include:
· Violent, sexual, or religious thoughts
· Fear of being infected by germs or dust
· Relationship-related obsessions
· Perpetual doubts (is the front door locked?)
· Obsessive ruminations that oblige a return to the same word, sentence or insolvable problem

Common compulsions include:
· Excessive washing or cleaning to avoid contamination
· Repeated checking or counting
· Nervous rituals, such as opening a door a certain number of times before entering a room
· Arranging things meticulously by size, colour, or number

AMI-Quebec offers support groups for family, friends, and people living with Obsessive Compulsive Disorder. Click HERE for more information.

Panic Disorder: Recurrent, unexpected panic attacks, followed by at least 1 month of concern about having additional attacks, worry about the implications of consequences of the attack, or a significant change in behaviour related to the attacks.  Panic attacks may last from a few minutes to a few hours, and are accompanied by a sense of looming danger and a strong desire to escape. Individuals often experience dizziness, chest discomfort, choking, sweating, and various other physical symptoms.

Anticipation or fear of panic attacks may further complicate the problem and increase anxiety. Panic disorder is often accompanied by agoraphobia: fear and avoidance of places or situations from which escape might be difficult in the event of a panic attack.

Post Traumatic Stress Disorder (PTSD): A condition that may develop after exposure to a traumatic even or series of events, such as rape, serious injury, or natural disaster, where physical harm occurred or was threatened. Individuals may experience flashbacks, persistent frightening thoughts and memories, anger or irritability.

Social Phobia (Social Anxiety Disorder): Intense fear and anxiety in response to social or performance situations; may include palpitations, tremors, gastrointestinal discomfort, and other physical symptoms that may meet criteria for a panic attack.

Specific Phobia: Persistent fear related to exposure to specific objects or situations (such as fear of heights or of a specific animal). Individual may logically know that the fear is unreasonable but still find it difficult to control the anxiety.

AMI-Quebec offers support groups for family, friends, and people living with Anxiety. Click HERE for more information.

For more information on anxiety and related disorders:
Anxiety and Depression Association of America
Anxiety Canada
Panic Disorder
Understanding Agoraphobia & Panic Disorder

For more information on OCD:
Obsessive Compulsive Foundation
Obsessive Compulsive Disorder Symptoms, Causes, and Effects (USA)

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Eating Disorders

Eating disorders are conditions characterized by harmful eating habits and an unhealthy preoccupation with food to the detriment of an individual’s physical and mental health. Anorexia nervosa and bulimia nervosa are the most common eating disorders. Between 50% to 75% of individuals with an eating disorder also experience depression.

Anorexia nervosa: characterized by excessive food restriction and irrational fear of gaining weight, as well as a distorted body image. People suffering from anorexia are usually significantly underweight but may engage in behaviours such as repetitive weighing, measuring, mirror gazing, and other actions to make sure they are still thin, a common practice known as “body checking”. Individuals continue to feel hunger, but deny themselves all but very small quantities of food.  This may result in physical symptoms such as metabolic and hormonal disorders, dizziness, headaches, drowsiness, lack of energy, amenorrhea (absence of menses) and complications in every major organ system in the body.

Bulimia nervosa: characterized by cycles of binge eating and purging, which involves rapid and out-of-control eating, followed by vomiting or other forms of purging, like taking a laxative, diuretic, or stimulant. Cycles may be repeated several times a week and directly cause many physical symptoms including peptic ulcers, dental erosion, chronic gastric reflux, and dehydration. Individuals may show an obsession about weight and a fixation on calorie counting and exercise as well as a distorted body image and low self-esteem.

Binge-eating disorder: characterized by over-eating. Individuals report losing control over what they eat and how much they eat. Usually, people over-eat to comfort themselves and is sometimes used as a way of coping. Binge-eating disorder can trigger and increase the risk of type II diabetes, high blood pressure, and/or weight concerns.

For more information on eating disorders:
Anorexia and Bulimia Quebec
National Eating Disorder Information Centre

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Hoarding is characterized by the excessive accumulation of objects and the inability or unwillingness to discard these acquisitions. Individuals with this problem may have exaggerated beliefs about the importance or usefulness of these objects, and are very reluctant to part with them. In more severe cases, the clutter may completely cover surfaces in the home, preventing the use of a living space as it was originally intended. It can also be dangerous and may put the individual or others at risk from fire, falling, respiratory problems, and other health concerns.

AMI-Quebec offers support groups for family, friends, and people with Hoarding problems.  Click HERE for more information.

For more information on hoarding:
The Goods on Hoarding
eSanté Mentale

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Personality Disorders

Personality disorders reflect characteristics and traits that are expressed inappropriately and become maladaptive. These enduring and inflexible patterns of thinking and behaviour deviate from the expectations of society, leading to distress or impairment. Some forms of personality disorders may interfere very little with the individual’s function, while others may be very debilitating and cause impairments in social and occupational functioning.

Antisocial Personality Disorder: Disregard for and violation of the rights of others. Individual may be in continuous social or legal trouble and may appear to profit very little from discipline.

Avoidant Personality Disorder: Social inhibition, feelings of inadequacy, and hypersensitivity to negative evaluation.

Borderline Personality Disorder: Rapid and drastic changes in mood, unstable interpersonal relationships, prone to impulsive and sometimes self-damaging action, unstable self-image.

Borderline Personality Disorder (BPD) is a condition that affects the way a person understands him/herself and the way he/she relates to the world around them. Individuals with BPD are highly sensitive and have great difficulty regulating their emotions and impulses. They often experience significant challenges in five areas:

Emotions: Difficulty managing emotions such as anxiety, depression and anger; their mood changes rapidly, usually in response to a stressful event (this is called emotion dysregulation, which may also be associated with disorders other than BPD).

Interpersonal Relationships: Difficulty sustaining relationships; fear of being abandoned.

Self: Difficulty knowing who they are, how they feel and what they like; feeling empty and lonely.

Behaviour: Impulsive and risky behaviours (substance abuse, binge eating, gambling, self-injury).

Cognition: Difficulty with concentration or problem solving. Paranoid thoughts in response to stressful events. Delusions and sensations or feelings that aren’t based in reality.

Learn more about BPD here. AMI-Quebec offers an education program for caregivers of people with Borderline Personality Disorder. Click HERE for more information.

Dependent Personality Disorder: Submissive and clinging behaviour related to an excessive need to be taken care of.

Histrionic Personality Disorder: Excessive emotionality and attention-seeking.

Narcissistic Personality Disorder: Grandiosity, need for admiration, and lack of empathy.

Obsessive-Compulsive Personality Disorder: Pervasive preoccupation with orderliness, perfectionism and control often beginning in early adulthood. May be unreasonably insistent on a particular way of doing things or excessively devoted to work; individuals affected by this disorder sometimes show reduced affection and generosity.

Paranoid Personality Disorder: Distrust and suspiciousness in which others’ motives are interpreted as malevolent. Behaves towards others with unwarranted suspicion, envy, jealousy or stubbornness.

Schizoid Personality Disorder: Detachment from social relationships and a restricted range of emotional expression.

Schizotypal Personality Disorder: Acute discomfort in close relationships, cognitive or perceptual distortions, and eccentricities of behaviour.

For more information on personality disorders:
Borderline Personality Disorder Central
Mayo Clinic: Personality Disorders

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Psychosis is a medical condition and refers to a mental state characterized by a person’s loss of contact with reality. Individuals may experience hallucinations, delusions, thought disorder, personality changes, and impaired insight. Depending on its severity, this may be accompanied by bizarre behaviour, violent tendencies, difficulty with social interaction, and a disturbance in daily life activities. Psychosis is commonly associated with schizophrenia, and sometimes with depression, bipolar disorder, schizoaffective disorder, and certain personality disorders. It can also be a result of illicit drug use and a large number of medical conditions.

For more information on psychosis:
Early Psychosis

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Schizoaffective Disorder

Some people experience symptoms of both schizophrenia and bipolar disorder. Individuals suffering from schizoaffective disorder experience recurring abnormal mood as well as psychotic components similar to those seen in schizophrenia. Mood may be elevated, depressed, or simultaneously elevated and depressed, and mood changes alternate or co-occur with psychotic symptoms. Along with symptoms of mania and depression, individuals may experience hallucinations, disordered thought processes, and delusions, often adversely effecting social and occupational function.

For more information on schizoaffective disorder:
Here To Help

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Schizophrenia is a disorder that affects mental processes such as thinking and judgment, sensory perception and the ability to appropriately interpret and respond to situations. Common symptoms include mixed-up thoughts, delusions, hallucinations, bizarre behaviour, and difficulty with tasks that require abstract memory and sustained attention. Schizophrenia is not to be confused with Dissociative Identity Disorder (sometimes referred to as multiple personality disorder or “split personality”), as the two are very different. About 1% of the Canadian population suffers from schizophrenia, and the first symptoms usually emerge in young-adulthood.

The symptoms of schizophrenia vary greatly among individuals. For a diagnosis to be made, symptoms must be present most of the time for a period of at least 1 month. Many clinicians find it useful to classify these symptoms as either “positive”,”negative,” or “cognitive.”

Positive symptoms reflect an excess or distortion of normal functions and may include:
· Delusions: persistent beliefs or suspicions not grounded in reality, often involving misinterpretation of perception of experience.
· Hallucinations: hearing, feeling or seeing things that exist only in the individual’s mind
· Thought disorders: unusual or dysfunctional ways of thinking and organizing thoughts. Individuals may have difficulty speaking, often sounding incoherent or stopping mid-sentence.
· Disorganized behaviour: this may range from childlike silliness or dressing inappropriately to unpredictable agitation.
· Movement disorders: agitated or repetitive body movements.

Negative symptoms refer to a diminishment or absence of characteristics of normal function and may include:
· Loss of interest in or reduced ability to carry out everyday activities
· Lack or flatness of emotion, apathy
· Social withdrawal
· Neglect of personal hygiene
· Loss of motivation
· Inability to experience pleasure

Cognitive Symptoms involve problems with thought processes and may interfere with the ability to perform routine daily tasks. They include:
· Poor “executive functioning” (the ability to understand information and make decisions)
· Difficulty focusing or paying attention
· Memory problems

For more information on schizophrenia:
Schizophrenia Society of Canada – support group chapters across Canada
The Schizophrenia Home Page


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