Mental Health Definitions

Mental illnesses come in all shapes and sizes and can affect any person regardless of race, sex, religion,
or socioeconomic status. Learn about the symptoms and causes of each of the most common mental illnesses below!


Mild Depression:
Mild Depression is typically diagnosed when an individual experiences constant feelings of sadness and hopelessness. In addition, the individual typically loses interest in activities they once liked. These feelings typically last, on average, four days a week for two years+ and interfere with one's daily activities. Symptoms:
Self-loathing Feelings of guilt Lack of motivation Weight change (gain or loss) Insomnia Aches or pains with no direct cause Fatigue throughout the day Difficulty concentrating Moderate Depression: In addition to the duration and symptoms of Mild Depression, Moderate Depression can cause issues at home, work, and within your social life. Additional Symptoms:
Self-Esteem issues Overwhelming worry Feelings of worthlessness Reduced work output Severe (Major) Depression: Severe or Major Depression includes the symptoms of both Mild and Moderate Depression and may last consistently for six months. Additional Symptoms:
Hallucinations Suicidal thoughts/actions Delusions Illogical thoughts

Bipolar Disorder

Bipolar I: When a person experiences Bipolar I, they typically endure a manic episode that lasts at least 7 days. In addition, they may experience a major depressive episode, although this is not essential to the diagnosis. Symptoms of mania:
Euphoria Increased sexual desire Hallucinations/
Delusions Less need for sleep Increase in energy Risky/Reckless behavior Symptoms of depression:
Insomnia Random crying Fatigue Loss of interest in your usual activities Thoughts of suicide

Bipolar II: Just like Bipolar I, a person that has Bipolar II will most likely experience major depression episodes, manic episodes, and times when they are symptom-free. Hypomania, a less severe form of mania (usually indicated by increased energy levels), is less common among those with Bipolar II.
Cyclothymic Disorder: A person who has Cyclothymic Disorder experiences mood swings, however, they are less severe compared to those experienced by people who have Bipolar I or Bipolar II​ which means that the illness can be hard to diagnose.
Symptoms last for months or even years without a break.

Anxiety Disorder

Anxiety is characterized by excessive worrying that can hinder an individual from completing daily tasks or activities. Generally, the amount of worry is not proportionate to the risk associated with the situation. The following symptoms must not be related to other medical conditions a person may be experiencing in order to be classified as anxiety disorder. Symptoms: Fatigue Inability to concentrate Anger or Irritability Restlessness Trouble sleeping Muscle aches or soreness Other symptoms: Sweating Nausea Diarrhea

Post Traumatic Stress Disorder (PTSD)

PTSD is diagnosed through different criteria; learn about the symptoms of each category below. Criterion A An individual who has experienced, witnessed, learned about, or has been exposed to details of a traumatic event. Criterion B An individual who has experienced one or more of the following symptoms:

  • Reoccurring memories of the traumatic event
  • Repeated nightmares related to the traumatic event
  • Feelings as though the traumatic event is happening again (i.e. flashbacks)
  • Worry and fear when exposed to triggers that exist either inside or outside of your body that remind you of the traumatic event
  • Physical reactions when reminded of the traumatic event (i.e. heart rate increases)
Criterion C An individual who attempts to avoid thoughts, feelings, people, places, activities, etc. associated with a traumatic event. Crierion D An individual who has negative changes in their thoughts or moods after the traumatic event. They will develop two or more of the following symptoms:
  • Unable to remember an important part of the traumatic event
  • Pessimistic point of view
  • Self-blame or blame of others regarding the cause of the traumatic event
  • Poor emotional state (i.e. shame, anger...)
  • Loss of interest in activities
  • Detachment from others
  • Unable to be positive
Criterion E An individual who experiences at least two of the following changes in arousal after a traumatic event:
  • Anger or aggressive behavior
  • Impulsive/self-destructive behavior
  • Unable to concentrate
  • Sleep issues
  • Always on guard
  • A jumpy reaction to sudden noise or movement
Criterion F
An individual who experiences Criterion E symptoms for more than one month. Criterion G
An individual whose symptoms post-traumatic event brings a large amount of distress and interferes with their daily life. Criterion H
The symptoms listed are not the cause of a medical condition or substance use.

Eating Disorders

Anorexia Nervosa An individual with Anorexia ​Nervosa has an intense fear of gaining weight and feels they must control their weight/shape as a way to deal with deep-rooted problems. Physical Symptoms (not all are listed here):

  • Weight loss
  • Fatigue
  • Insomnia
  • Thin hair (may fall out)
  • Dizziness/fainting
  • Constipation or stomach pain
  • Menstrual period stops
  • Intolerance to cold
  • Dehydration
Emotional Symptoms (not all are listed here):
  • Constantly thinking about food
  • Skipping meals
  • Lying about food eaten
  • Irritability
  • Avoiding eating in public
  • Eating only "safe" foods
Bulimia Nervosa Bulimia can be defined as binging and purging; eating a large amount of food and then getting rid of it in a harmful way (vomiting, laxatives, etc.) to prevent weight gain. Symptoms (not all are listed here):
  • Distorted or negative body image
  • Dieting/fasting/binge eating
  • Constant worry about being fat
  • Excessive exercising
  • Damage to teeth/gums
  • Weight change
  • Sores/calluses on knuckles or hands
  • Swelling in one's face and cheeks
Binge Eating Disorder
​​​​​An individual with binge-eating disorder typically eats a large amount of food without having the control to stop. This typically happens on a regular basis. Symptoms (not all are listed here):
  • Eating behaviors that are out of control
  • Consuming food when you're not hungry
  • Eating until you feel uncomfortable
  • Consuming large amounts of food within a short period of time
  • Feelings of shame about one's eating habits
Orthorexia Nervosa Individuals with Orthorexia Nervosa are fixated on eating a "clean" diet and avoid eating foods that you deem to be unhealthy. Symptoms (not all are listed here):
  • Obsessive thinking about food or planning your meals
  • Obsessive research about food to determine, in your mind, if it is safe to eat
  • Excluding groups of foods from your diet
  • Fear of eating a meal with unknown ingredients
  • Judgement of others for their food choices

Adjustment Disorder

Diagnosis of adjustment disorders is based on identification of major life stressors, your symptoms, and how they impact your ability to function. It is a group of symptoms, such as stress, feeling sad or hopeless, and physical symptoms that can occur after you go through a stressful life event. The symptoms occur because you are having a hard time coping. Your reaction is stronger than expected for the type of event that occurred. Per the DSM 5: - Having emotional or behavioral symptoms within 3 months of a specific stressor occuring in your life. - Experiencing more stress than would normally be expected in response to a stressful life event and/or having stress that causes significant problems in your relationships, at work or at school. - Symptoms are not the result of another mental health disorder or part of normal grieving. There are several types of adjustment disorder including: with depressed mood, anxiety, and/or disturbance of conduct.


Characterized as disruptions to a person's thoughts and perceptions that make it difficult for them to recognize what is real and what isn't. These disruptions are often experienced as seeing, hearing, and believing things that aren't real or having strange and persistent thoughts, behaviors, adn emotions. There are a variety of symptoms for psychosis but the most common two are hallucinations and delusions. Hallucinations are seeing, hearing, or feeling things that aren't there, such as the following: - Hearing voices (auditory hallucinations) - Strange sensations or unexplainable feelings - Seeing glimpses of objects or people that are not there or distortions Delusions are strong beliefs that are not consistent with the person's culture, are unlikely to be true, and may seem irrational to others, such as the following: - Believing external forces are controlling thoughts, feelings, and behaviors - Believing that trivial remarks, events, or objects have personal meaning or significance - Thinking you have special powers, are on a special mission, or even that you are God

Obsessive Compulsive Disorder (OCD)

OCD is a common disorder in which the person experiences uncontrollable reoccurring thoughts and/or behaviors that they feel the urge to repeat. Those with OCD may experience symptoms of obsessions and/or compulsions that interfere with their day to day functioning and engagement in activities. Obsessions are repeated thoughts, urges, or mental images that cause anxiety. - Examples of obsessions are fear of germs, having things in perfect order or symmetrical, aggressive thoughts towards others. Compulsions are repetitive behaviors that are in response to an obsessive thought. Some common compulsions are: - Ordering or arranging items in a certain way - Excessive cleaning or hand washing - Repeatedly checking on items (if the door is locked) - Compulsive counting

Schizophrenia Spectrum and Other Psychotic Disorders

Criterion A: Two (or more) of the following, each present for a significant period of time during a one month period. At least one symptom must be 1-3. 1. Delusions 2. Hallucinations 3. Disorganized speech 4. Grossly disorganized or catatonic behavior 5. Negative symptoms (diminished emotional expression or avolition) For a significant amount of time since the onset of symptoms, there has been decreased functioning in daily activities (school, work, self-care, etc.). Continuous signs of the disturbance are persistent for at least 6 months, including at least 1 month of symptoms that meet the Criterion A. This time may include residual periods where there are primarily negative symptoms.

Panic Attacks

An abrupt surge of intense fear or intense discomfort that reaches a peak within minutes and during which time 4 or more of the following symptoms occur: - Palpitations, pounding heart, increased heart rate - Sweating - Trembling or shaking - Feeling short of breath or smothering - Feelings of choking - Chest pain or discomfort - Nausea or abdominal distress - Feeling dizzy, unsteady, lightheaded, or faint - Feelings of unreality or detached from oneself - Fear of losing control or "going crazy" - Fear of dying - Numbness or tingling sensations - Chills or heat sensations


A marked fear or anxiety about two (or more) of the following: - Using public transportation - Being in open spaces - Being in enclosed spaces (shops, movie theaters, etc.) - Standing in line or being in a crowd - Being outside the home alone These situations are avoided, marked with distress or anxiety of having a panic attack. The fear experienced is out of proportion to the actual danger posed by the situation. The fear, anxiety, or avoidance is persistent, usually lasting 6 or more months and causes significant impairment in daily functioning.

Social Anxiety Disorder

Fear or anxiety about one or more social situations in which the individual is exposed to possible scrutiny by others. For example, social interactions, being observed, and performing in front of others. The social situations almost always provoke fear and anxiety. The fear or anxiety is out of proportion to the actual threat posed by the situation. These social situations are endured or avoided with intense fear or anxiety. The fear, anxiety, or avoidance causes dysfunction in daily activities or social engagement. The fear, anxiety, or avoidance is persistent and lasts for over 6 months.