Words shape how we see our minds. When you understand mental health terms, big, scary labels turn into useful tools and vague worries can become clear next steps. A shared vocabulary helps you spot red flags earlier, ask sharper questions, and support friends with real empathy. It also makes appointments less confusing and self-advocacy more effective at school, work, and home.

Acute: A condition or symptom that appears suddenly and has a strong, immediate impact

Affect: The outward display of inner emotion that other people can observe

Anhedonia: A reduced ability to experience pleasure that often improves when depression is effectively treated

Antidepressant Medicine: Medication used to treat depression and many anxiety disorders. Benefits commonly become noticeable after six to eight weeks.

Antipsychotics: Medications used primarily to treat psychosis that can also help with severe mood symptoms or aggression

Antisocial Personality Disorder: A personality disorder defined by a persistent pattern of violating the rights of others without remorse that begins in childhood or adolescence and continues into adulthood

Anxiety: An uncomfortable set of physical sensations and thoughts that signal perceived threat and that becomes problematic when daily life is disrupted

Anxiety Disorders: Conditions characterized by excessive anxiety that interferes with functioning, including social anxiety disorder, panic disorder, separation anxiety disorder, and generalized anxiety disorder

Atypical Antipsychotics: Newer antipsychotic medications used for psychosis and sometimes for severe mood symptoms or aggression

Avolition: Very low motivation to initiate or complete activities, which is not the same as laziness

Axon: The long neuronal fiber that carries signals to other nerve cells

Benzodiazepines: Medications commonly used to treat anxiety, severe restlessness, and agitation when used correctly

Bipolar Disorder (Manic Depression): A mood disorder that includes at least one major depressive episode and at least one manic episode

Bipolar Disorder Type 2 (Hypomanic Depression): A mood disorder that includes at least one major depressive episode and at least one hypomanic episode

Borderline Personality Disorder (BPD): A personality disorder marked by emotion regulation difficulties, unstable relationships, poor self-image, and impulsive or self-harming behaviors

Brain: The body’s master control center for thought, emotion, and behavior that contains many interconnected parts, including:

  • Amygdala: A brain region involved in emotional memory, fear responses, arousal, and hormone release that prepares the body for action
  • Brain Stem: A relay hub between the body and higher brain areas that also helps control breathing, digestion, heart rate, sleep, and arousal
  • Cerebellum: A coordinator of movement, balance, and muscle tone
  • Cerebrum: The largest brain region, responsible for attention, reasoning, and abstract thought and composed of the frontal, occipital, parietal, and temporal lobes
  • Frontal Lobe: A lobe that supports movement, planning, reasoning, emotions, and problem-solving
  • Gray Matter: Brain tissue composed largely of neuron cell bodies that appears darker than white matter
  • Hippocampus: A structure that helps form memories, supports learning, and regulates emotional responses
  • Hypothalamus: A regulator of temperature, sleep, appetite, sexual drive, stress reactions, and hormone release from the pituitary gland
  • Limbic System: A network involved in emotion, memory, motivation, appetite, and arousal
  • Locus Coeruleus: A small brain stem area that activates norepinephrine pathways involved in arousal, anxiety, and fear
  • Myelin: An insulating sheath around axons that speeds nerve signaling and is often called white matter
  • Occipital Lobe: A lobe that processes visual information
  • Parietal Lobe: A lobe that supports recognition, spatial awareness, taste, and aspects of touch
  • Temporal Lobe: A lobe that processes sounds and supports recognition and memory of objects and faces
  • Thalamus: A relay for sensory and motor signals that also helps regulate sleep and wakefulness

Chronic: A descriptor for conditions that persist over a long period, often for years

Cognition: Mental processes involved in thinking, learning, planning, and memory

Cognitive Behavioral Therapy: A psychotherapy that helps people change unhelpful thoughts and behaviors to reduce symptoms and improve functioning

Cognitive Symptoms: Difficulties in thinking processes, such as negative thoughts in depression, delusions in psychosis, or impaired planning and problem-solving

Community Treatment: Care delivered outside a hospital, including in doctor’s offices, clinics, schools, or community health centers

Computed Axial Tomography (CAT) Scan: A specialized X-ray technique that creates images of brain structures

Compulsions: Repetitive behaviors performed to reduce anxiety from unwanted thoughts or to satisfy strong urges.

Conduct Disorder (CD): A disruptive behavior disorder involving a persistent pattern of rule-breaking and aggression, such as stealing, fighting, or setting fires

Delusion: A fixed false belief that does not match reality and that commonly appears in psychosis

Dendrite: A branching extension of a neuron that receives signals from other neurons

Depressant: A substance that slows thinking or physical activity, including alcohol and certain pain medications

Depression: Both a mood state and a diagnosable disorder that can include persistent sadness or irritability along with symptoms such as loss of interest, hopelessness, sleep or appetite changes, fatigue, and suicidal thoughts

Depressive Episode: A period that lasts at least two weeks and includes several characteristic depressive symptoms

Diagnosis: The identification of a medical or mental disorder using accepted criteria by trained professionals

Disorder: A disturbance of physical or mental health

Distress: Mental or physical suffering that can be part of normal life and is not itself a mental disorder

Double Depression: The co-occurrence of major depressive disorder and dysthymic disorder in the same person

Dysthymic Disorder: A chronic mood disorder marked by persistently low mood and fewer symptoms than major depressive disorder that still impairs daily life

Electroconvulsive Therapy (ECT): A treatment for severe mental disorders in which a controlled electrical current is applied to the brain under anesthesia

Electroencephalography (EEG): A test that measures the brain’s electrical activity using scalp electrodes

Euphoria: An abnormally elevated sense of well-being or joy that can occur in bipolar disorder

Evidence-Based Medicine (EBM): Care that uses the best available scientific evidence to guide treatment decisions

Extraversion: A personality trait describing sociable and outgoing behavior

Functional Impairment: Reduced ability to function as usual in areas such as family, school, work, or relationships

Functional Magnetic Resonance Imaging (fMRI): A brain imaging method that tracks blood flow changes to show how the brain functions

Generalized Anxiety Disorder (GAD): Excessive, hard-to-control worry about multiple areas of life accompanied by physical symptoms such as headaches and muscle tension

Grief: A normal emotional response to the loss of a loved one that differs from a depressive disorder

Hospitalization: Admission to a hospital for diagnosis and treatment; in mental health care, this is generally reserved for severe symptoms or crises

Hypomanic Phase (Hypomania): A less severe form of mania associated with elevated energy, mood, or activity and often seen in bipolar disorder

Introversion: A tendency to focus inward on thoughts and feelings more than on the surrounding social world

Manic Phase: A period of very high energy and excessive activity in bipolar disorder that may require hospital care and responds to medications and other therapies

Medication: A medicine prescribed by a licensed clinician and regulated by government agencies

Mental Disorder: A disturbance of brain function that meets recognized diagnostic criteria and results from interactions between genetics and environment

Mental Health: A state of emotional, behavioral, and social well-being that can coexist with a well-managed mental disorder

Mental Health Issue: A broad phrase that can refer to distress, suffering, or a diagnosable disorder and that is best replaced with more specific language

Mental Health Nurse: A registered nurse with specialized training in promoting mental health and treating mental disorders

Mental Health Professional: A trained provider who improves mental health or treats mental disorders

Mental Illness: Brain-based disorders that affect mood, behavior, and thinking, also often called mental disorders

Mood: An ongoing internal emotional state

Mood Disorders: Conditions involving problems with mood regulation, including major depressive disorder, bipolar disorder, and dysthymia

Mood Stabilizers: Medications that help even out mood and are commonly used in bipolar disorder

Narcissistic: A tendency to interpret experiences primarily in relation to the self with an unrealistically high sense of self-worth

Neurodevelopment: Growth and change of the brain over time.

Neuron (Nerve Cell): A specialized brain and spinal cord cell that processes and transmits information

Neuroscience: The scientific study of the brain and nervous system

Neurotransmission: Communication between neurons in which chemicals cross the synapse to send a signal

Neurotransmitters: Chemical messengers that carry signals between brain cells, including dopamine, serotonin, and noradrenaline

Obsessions: Repetitive, persistent, unwanted thoughts that cause distress and interfere with functioning

Obsessive-Compulsive Disorder (OCD): A disorder involving persistent unwanted thoughts and repetitive behaviors performed to reduce anxiety

Panic Attack: A sudden surge of intense fear or discomfort that includes symptoms such as dizziness, trembling, sweating, shortness of breath, and rapid heart rate

Panic Disorder: A disorder involving recurrent panic attacks, fear of more attacks, and avoidance of places where escape may be difficult

Personality Disorders: Long-standing patterns of behavior and inner experience that cause difficulties across situations

Positron Emission Tomography (PET) Scans: Imaging studies that use small amounts of radioactive material to measure brain activity and chemistry

Postpartum Depression: A mood disorder affecting women after childbirth that’s more severe and persistent than the “baby blues”

Postsynaptic Neuron: The neuron that receives signals across a synapse

Post-Traumatic Stress Disorder (PTSD): A disorder that can follow a terrifying, painful, or life-threatening event and that includes intrusive memories or nightmares and avoidance of reminders

Presynaptic Neuron: The neuron that sends signals across a synapse

Psychiatrist: A medical doctor who specializes in diagnosing, treating, and helping prevent mental disorders

Psychiatry: The medical specialty focused on understanding, diagnosing, and treating mental disorders

Psychologist: A doctoral-level psychology specialist who may practice clinically, teach, or conduct research

Psychomotor: The link between mental processes and physical movement

Psychomotor Agitation: Movement driven by mental tension, including behaviors such as pacing or picking at skin

Psychomotor Retardation: Noticeably slowed thinking and body movement

Psychosis: A state in which a person has difficulty distinguishing reality and may experience delusions, hallucinations, or disorganized thinking

Psychotherapy: Treatment for emotional, behavioral, personality, and other psychiatric concerns that uses structured communication between a clinician and a patient

Receptor: A site on a neuron where neurotransmitters or medications bind and influence signaling

Recovery: A state in which a person with a mental disorder functions as well as possible and feels mentally healthy even if the disorder is still present

Risk Factor: Any attribute that increases the chance of developing a disorder and that does not by itself cause the disorder

SAINT: Stanford Accelerated Intelligent Neuromodulation Therapy, an accelerated form of transcranial magnetic stimulation

Schizoaffective Disorder: A condition that includes features of both schizophrenia and a major mood disorder

Schizophrenia: A disorder that involves psychotic symptoms such as delusions and hallucinations along with other difficulties that impair daily life

Seasonal Affective Disorder (SAD): A form of major depressive disorder that occurs mostly at particular times of year, often in winter

Selective Serotonin Reuptake Inhibitors (SSRIs): Medications commonly used to treat depression that primarily affect the brain’s serotonin system

Self-Harm: Any self-inflicted injury without intent to die

Separation Anxiety Disorder: An anxiety disorder in children characterized by extreme difficulty being away from a parent

Serotonin: A neurotransmitter involved in regulating mood, anxiety, thinking, and other brain functions

Single Photon Emission Computed Tomography (SPECT): An imaging technique used to study brain function

Social Phobia (Social Anxiety Disorder): Fear and avoidance of social situations due to worry about scrutiny or judgment

Social Worker: A professional trained to address social, emotional, and environmental issues linked to disorders or disabilities

Sociopath (or Psychopath): A person who meets criteria for antisocial personality disorder

Sociopathy: The pattern of behavior and personality traits seen in a sociopath, including superficial charm and lack of remorse

Specific Phobia: An anxiety disorder involving intense fear of a particular object or situation that often responds to behavior therapy

Stress: The body’s response to disruptions in normal balance that can aid adaptation but can harm health when excessive

Suicidality: A broad reference to thoughts or actions related to wanting to die that is clearer when described with specific terms such as thoughts, plans, attempts, or deaths

Suicide: Death resulting from an action intended to end one’s life

Suicide Attempt: A self-directed, potentially harmful act with intent to die that does not result in death

Suicidal Ideation: Thoughts, images, or fantasies about harming or killing oneself

Suicidal Intent: The expectation and commitment to die by suicide that can be described in future or past tense

Suicidal Plan: A specific plan formed to attempt suicide

Synapse or Synaptic Space: The gap between neurons where neurotransmitters are released to regulate signaling

Syndrome: A collection of signs and symptoms that together describe a disease

Systematic Desensitization: A psychological treatment that gradually exposes a person to feared situations so that fear decreases over time

Therapist: A trained professional who practices a specific type of therapy

Therapy: The treatment of a disease or disorder by any method

Tolerance: A reduced response to a medication or treatment over time

Transcranial Magnetic Stimulation (TMS): A noninvasive treatment for depression that stimulates specific areas of the brain with magnetic pulses

Trauma: An event or injury that damages physical or mental health

Treatment: Medical, psychological, social, or surgical care provided to a patient

Trichotillomania: A disorder in which people repeatedly pull out their hair and often feel tension before pulling and relief or pleasure afterward

Voluntary Admission: Hospital admission for mental health treatment with the person’s agreement

Voluntary Patient: A person who remains in a psychiatric facility with personal consent or with the consent of a substitute decision-maker

Withdrawal: The brain’s response to suddenly stopping a medication or drug, which can include nausea, chills, cramps, diarrhea, or hallucinations but does not by itself indicate addiction. The term also refers to pulling away from social contact, which can occur in conditions such as depression, schizophrenia, and panic disorder.

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