mental disorders

Three main criteria are used to determine if something would be considered a mental disorder or if someone has a mental disorder:

• Level of dysfunction:

• Perception of distress:

• Deviation from the social norm:

Level of dysfunction:

is the person unable to do things that people typically can? To what extent do these things impact their life?

Perception of distress:

is the person harmed by these traits? Do these traits decrease their mental wellbeing?

Deviation from the social norm:

are the person’s experiences significantly different from what is typical? This can vary between cultures.

Being diagnosed with a mental disorder can be considered

positive or negative for a person depending on the specific disorder, the specific person, the level of stigma around the disorder, and factors related to discrimination, racism, sexism, and ageism.

Labels can cause us

to make unjustified assumptions about people, but they can also be a revelation for other people and help them get access to support.

Psychologists and psychiatrists use two manuals to classify and diagnose mental disorders.

• The International Classification of Diseases (ICD)

• The Diagnostic and Statistical Manual of Mental Disorders (DSM)

The International Classification of Diseases (ICD)

is a manual used worldwide that includes many different diseases and disorders, not just psychological ones.

The Diagnostic and Statistical Manual of Mental Disorders (DSM)

• is a manual created by the American Psychological Association and is used primarily in the United States, although also in other countries.

• it only contains information about mental and psychological disorders.

Why were both the ICD and the DSM revised?

revised due to new scientific and psychological information and viewpoints. As of 2025, we are currently on the DSM-5-TR (5th edition, text revision) and the ICD11 (11th edition).

What do psychologists and psychiatrists think causes mental disorders?

Psychologists and psychiatrists are not sure what causes mental disorders, but the current scientific consensus is that it’s a mix of genetic, environmental, and biological factors (biopsychosocial approach).

The diathesis stress model says that

mental disorders develop as a result of genetic predispositions (diathesis) and stressful life experiences (stress).

Behavioral perspective

• Maladaptive (not suitable for the situation) learned associations between or responses to stimuli

• Example: A veteran associating any explosion with war, even the explosions of fireworks and firecrackers.

Psychodynamic perspective

• Unconscious thoughts and experiences, commonly developed during childhood

• Example: A child frequently feels angry towards their parents. They begin to have unconscious anger for all authority figures and frequently lash out at their bosses as an adult.

Humanistic Perspective

• Lack of social support, inability to fulfill one’s potential

• Example: A woman in poverty raising 2 small children has very little social support to help her handle the stress and develops an anxiety disorder.

Cognitive Perspective

• Maladaptive thoughts, beliefs, attitudes, or emotions

• Example: After a streak of bad luck, a man starts to believe he is worthless and ends up developing depression.

Evolutionary Perspective

• Behaviors and mental processes that reduce the likelihood of survival

• Example: A person with borderline personality disorder frequently makes rash and emotional decisions, endangering themself and others.

Sociocultural perspective

• Maladaptive social and cultural relationships/dynamics

• Example: After moving to a new country, a teenager struggles to fit in and understand the country’s culture, and begins to feel depressed and anxious because of it.

Biological Perspective

• Physiological and genetic issues

• Example: A woman and her husband have ADHD. Because ADHD has a significant genetic component, 2 out of her 3 children also have ADHD.

What do most psychologists use when determining the cause of someone’s mental illness or disorder.

Most psychologists use an eclectic approach (mix of all of these) when determining the cause of someone’s mental illness or disorder.

Neurodevelopmental disorders are

disorders that affect the way someone’s brain develops and functions. Unlike most other disorders, neurodevelopmental disorders have an onset before or soon after birth and last someone’s entire life.

Neurodevelopment disorders examples/types:

• Attention-Deficit/Hyperactivity Disorder (ADHD)

• Autism Spectrum Disorder (ASD)

Attention-Deficit/Hyperactivity Disorder (ADHD)

• is a common neurodevelopmental disorder that affects about 10% of the population.

• It involves a difficulty in executive function, a set of cognitive skills relating to someone’s ability to plan, concentrate, solve problems, and manage emotions.

• It is made up of 3 types of symptoms:

3 types of symptoms that make up ADHD

inattention, hyperactivity, and impulsivity.

Inattention

trouble directing one’s attention properly. This is more common in women with ADHD than men and can include lack of attention and abnormally high focus on a specific thing or topic.

Hyperactivity

excessive moment and energy that can result in impatience, restlessness, and overtalkativeness.

Impulsivity

quick and rash decision making—”not thinking before you speak”. This can result in making thoughtless decisions, engaging in dangerous behaviors without thinking about the consequences, or oversharing in a conversation.

Autism Spectrum Disorder (ASD)

is a neurodevelopmental disorder that impacts social functioning. It was created as a merger of several previously recognized disorders including autistic disorder and Asperger’s disorder. It is called a “spectrum disorder” because it can manifest in many different ways.

What two traits characterize autism?

Autism is characterized by 2 types of traits: social difficulties and restrictive/repetitive behaviors.2

Social difficulties

are difficulties that impair someone’s ability to communicate and socialize. Autistic people have trouble in the following domains:

• social reciprocity

• Nonverbal communication

• Maintaining relationships

Social reciprocity

someone’s ability to hold a back-and-forth conversation and respond to social cues

Nonverbal communication

someone’s ability to use and understand nonverbal gestures and vocal inflection

Maintaining relationships

making and keeping friends, relationships with family members

Restrictive and repetitive behaviors are

atypical, strong, fixated behaviors including:

• Atypical motor (physical) movements (“stimming”)

• Oversensitivity or undersensitivity to sensory stimuli such as sound and touch

• Strictly following routines and resistance to change

• Very strong and specific interests (“special interests”)

Autism encompasses a wide variety of levels of “functioning” and support needed.

Some autistic people may be able to live alone, have a job, and/or hide their autistic traits. Others might need a caregiver and not be able to hold a job.

What causes autism?

It is unclear what exactly causes autism, but most psychologists and psychiatrists agree that it is a combination of genetic factors and environmental factors in the womb. Vaccines do not cause autism.

Schizophrenia spectrum disorders

are a group of severe mental illnesses, such as schizophrenia and schizoaffective disorder, and that can be chronic or temporary.

Schizophrenia spectrum disorders are characterized by issues in what 5 areas?

• Delusions

• Hallucinations

• Disorganized speech/thinking

• Disorganized motor behavior

• Negative symptoms

Delusions

false beliefs about reality, despite incontrovertible proof to the contrary

Hallucinations

false sensory input, ie seeing or hearing things that aren’t really there

Disorganized speech/thinking

speech or thoughts that are jumbled or don’t make sense, “word salad”

Disorganized motor behavior

nonsensical and abnormal motor (physical) behavior, such as repeating a useless physical motion or being in a state of immobility and irresponsiveness (stupor).

Negative symptoms

symptoms that occur in healthy people but not people with schizophrenia spectrum disorders, such as flat affect (a lack of emotional expression) or a lack of movement (stupor)

Delusions, hallucinations, disorganized speech/thinking, and disorganized motor behaviors are examples of

positive symptoms

positive symptoms

symptoms that occur in people with schizophrenic spectrum disorders and not healthy people.

Psychosis

a general term for a collection of symptoms where someone is unable to distinguish between what’s real and what’s not. It includes symptoms such as hallucinations and delusions

Schizophrenic spectrum disorders annd genetics role?

Schizophrenic spectrum disorders are highly genetic, with a heritability of around 80%. Being born in winter months, prenatal virus exposure, and having a family member with a schizophrenic spectrum disorder increases someone’s risk of having a schizophrenic spectrum disorder.

The dopamine hypothesis of schizophrenic spectrum disorders hypothesizes that

these disorders are caused or influenced by increases in dopamine in certain areas of the brain.

Depressive disorders

• are disorders characterized by the long-term presence of a sad, empty, irritable mood and other psychological changes that affect a person’s ability to function.

• They can be, but are not necessarily, observable to other people around the depressed person.

• Having a depressive disorder increases someone’s risk of suicide or a suicide attempt, but not all depressed people will consider or attempt suicide.

Risk factors for depression include

both environmental factors and biological factors. A history of abuse, major life changes, and a family history of depression can increase someone’s risk.

Depressive disorders example/type:

• major depressive disorder (MDD)

• Persistent depressive disorder (PDD)

Major Depressive Disorder (MDD)

also just called “depression”, is one of the most common mental illnesses and is characterized by a depressed mood for at least two consecutive weeks.

Symptoms of depression include:

• a depressed mood

• loss of interest or pleasure in day-to-day activities, including typically fun activities such as hobbies

• fatigue, insomnia, and/or hypersomnia (oversleeping)

• feelings of worthlessness or guilt

• thoughts of death or suicide

a depressed mood

feelings of sadness, hopelessness, and/or emptiness most of the day, almost every day.

What is the major depressive disorder (DMD) also called & why?

Major depressive disorder is sometimes called the “common cold” of mental illnesses due to its prevalence.

Persistent Depressive Disorder (PDD)

• sometimes called “dysthymia”, is a long-term mental illness where someone experiences depressive symptoms most days for two years.

• It is characterized by the same symptoms of major depressive disorder but is typically not as severe as MDD, but it lasts for a very long period of time.

• A person can have both persistent depressive disorder and major depressive disorder.

Bipolar disorders are

• disorders characterized by long-term, cycling periods of depression and mania or hypomania.

• Each period lasts days to weeks.

• It is different from being emotional or rapidly cycling between emotions within a single day.

Bipolar disorder types/examples

• Bipolar I Disorder

• Bipolar II Disorder

Depression

a sad, hopeless, or empty mood that lasts for at least 2 weeks.

Mania

an abnormally euphoric or elevated mood that significantly affects social and/or occupational functioning and lasts for at least a week.

Hypomania

a less severe form of mania that doesn’t necessarily significantly affect social or occupational functioning and lasts for at least 4 days.

Bipolar disorders are highly heritable

• approximately 80 to 90 percent of people with bipolar disorder also have a relative with bipolar disorder.

• Stress, sleep disruption, and drug/alcohol use can also trigger bipolar disorders.

Bipolar I Disorder

• is a disorder characterized by at least one manic episode.

• Someone with this may have had hypomanic or depressive episodes as well, but it’s not necessary for a diagnosis.

Some symptoms of a manic episode associated with Bipolar I disorder include:

• inflated (increased) self-esteem

• decreased need for sleep

• being more talkative than usual

• racing thoughts or distractibility

• impulsive activities and choices such as shopping sprees

Some people who have a manic episode

• may need to be hospitalized due to the intensity of their episode.

• might also experience psychotic features (schizophrenialike symptoms such as hallucinations and delusions).

Bipolar II disorder

• is a disorder characterized by at least one hypomanic episode and at least one depressive episode.

• While a depressive episode is not required for a diagnosis of Bipolar I, it is required for a diagnosis of Bipolar II.

To be diagnosed with Bipolar II,

someone should have never had a full manic episode and have only had hypomanic episodes. If they’ve had a manic episode, they should be diagnosed with Bipolar I instead.

Symptoms of a hypomanic episode are

similar to symptoms of a manic episode, but don’t last as long, significantly affect occupational/social functioning, cause psychotic features, or result in hospitalization.

Anxiety disorders

are disorders characterized by excessive fear or worry.

Anxiety disorders types/examples

• generalized anxiety disorder (GAD)

• specific phobia

• social anxiety disorder

• agoraphobia

• panic disorder

to be diagnosed with an anxiety disorder

While everyone experiences stress sometimes, someone has to experience anxietyrelated symptoms to the point that it is interfering with their life for a long period of time.

what increases the likelihood of having an anxiety disorder?

• Low self-esteem, past traumatic experiences, and a family history of depressive or anxiety disorders can increase someone’s likelihood of having an anxiety disorder.

• Women are more likely than men to have an anxiety disorder.

Generalized Anxiety Disorder (GAD)

• sometimes called just “anxiety,” is characterized by abnormally high levels of worry about many different things that lasts at least 6 months.

• The anxiety is not restricted to social situations or one specific thing/situation.

Some symptoms of GAD include:

• excessive and/or uncontrollable levels of worry

• fatigue

• difficulty concentrating

• sleep disturbance

• restlessness

If MDD is the “common cold” of mental illnesses, GAD is

the flu — it is one of the most common mental illnesses and affects about 3% of people per year.

Specific Phobia

is a disorder characterized by excessive, disproportionately high anxiety about one specific thing or topic.

to be diagnosed with specific phobia

A lot of people have phobias, but to be diagnosed with specific phobia the phobia must be long-term and negatively affect someone’s wellbeing.

Some common phobias include

• acrophobia - fear of heights

• arachnophobia - fear of spiders

Social Anxiety Disorder

• is characterized by an excessive fear of being judged, watched, or scrutinized by others.

• This anxiety occurs in public situations such as talking with new people, eating dinner in public, or giving a speech.

What will people with social anxiety avoid?

People with social anxiety might avoid triggering social situations, or try to persist through them while feeling extreme fear.

Agoraphobia

is characterized by fear of being trapped or unable to escape while in a public space.

Some potentially anxiety-inducing situations for a person with agoraphobia

could include standing in line, being in a crowded place, or using public transportation.

Panic Disorder

• is an anxiety disorder in which people experience sudden, unexpected “panic attacks”.

• Someone with panic disorder might also feel additional anxiety about not knowing when they might have a panic attack or if one will happen in a public situation.

Panic attacks

can last for minutes to hours and are characterized by extreme fear and physical symptoms.

During a panic attack, someone might feel:

• intense terror

• a sensation of being unable to breathe

• sweating

• dizziness

• feelings of depersonalization (being disconnected from yourself) or derealization (being disconnected from the world)

depersonalization

being disconnected from yourself

derealization

being disconnected from the world

Obsessive-compulsive disorders

are disorders that involve uncontrollable and recurring thoughts (obsessions) and actions done to resolve the anxiety caused by those thoughts (compulsions).

What causes obsessive compulsive disorders?

These disorders may be caused by genetic factors, learned associations between stimuli, or maladaptive thinking.

Obsessive - Compulsive Disorders types/examples

• Obsessive-Compulsive Disorder (OCD)

• Hoarding Disorder

Obsessive-Compulsive Disorder (OCD)

• is a mental illness in which someone experiences obsessions and compulsions.

• Obsessions generally involve an irrational fear of something bad happening or unwanted urges to do things the person would never actually do (intrusive thoughts).

• To stop these obsessions, a person with OCD feels the need to do a compulsion

• A compulsion might not seem to have anything to do with an obsession, but it makes sense inside the person with OCD’s head.

• Someone with OCD might repeat a compulsion several times. They might also feel the need to restart a compulsion if they feel they’ve made a mistake.

Compulsion

a seemingly illogical task that relieves the anxiety caused by the obsession.

Some common topics of obsessions include:

• getting sick, having a rare disease, or things being contaminated

• having forgotten to do something important, such as lock the door

• harming oneself or other people

• things being unordered or asymmetric or otherwise “imperfect”

• unwanted sexual or violent imagery

Some common compulsions include:

• repeatedly washing one’s hands

• checking things repeatedly, such as if a stove is off

• counting things

• self-harming behaviors

Hoarding Disorder

• is a disorder in which people have difficulty throwing things away or getting rid of things, resulting in a large accumulation of extra stuff.

• Someone with Hoarding Disorder might feel distressed at the idea of getting rid of the items, feel that they need to save the items, or feel that the items will be sad if they throw them away.

• People with Hoarding Disorder feel this way regardless of an item’s monetary or sentimental value.

Dissociative disorders types/examples:

• dissociative amnesia

• dissociative identity disorder (DID)

Dissociative disorders

• are characterized by feelings of disconnect from your consciousness, identity, memory, emotion, perception, and even motor control.

• are thought to be caused by severe stress or trauma, particularly childhood trauma.

• People with might experience depersonalization.

Depersonalization

a feeling of detachment from your body, or like your body isn’t real or isn’t really yours

Derealization

a feeling of detachment from the world, or like the world isn’t real

Dissociative Amnesia

• happens when someone’s brain blocks out certain memories after a very stressful or traumatic experience.

• It is generally caused by the person’s brain trying to protect them from unpleasant, distressing, or traumatic experiences.

• People with this still have the memories, but can’t retrieve them.

• Some people with this might experience dissociative fugue