By Candida Fink, Joe Kraynak

acute: Relatively short but severe, as in an acute mood episode.

adjunctive: Complementary to the main treatment.

affective disorder: A category of psychiatric disorders that includes depression, bipolar disorder, and seasonal affective disorder (SAD). Affect is a medical term for mood.

akathisia: Severe restlessness, a possible side effect of certain medications, especially some antipsychotics.

anticonvulsant: A class of medications developed primarily to prevent epileptic seizures. Many anticonvulsants, including valproate (Depakote) and carbamazepine (Tegretol), are also useful in treating mania.

antidepressant: A class of medications effective in treating the symptoms of depression.

antipsychotic: A class of medications originally developed to reduce the frequency and severity of psychotic episodes. The newer atypical or second-generation antipsychotics are now also used to treat bipolar disorder or more severe depression. Many people who take these medications don’t have psychotic symptoms.

bipolar disorder: A psychiatric condition characterized by extreme mood states of mania and depression. A person may have bipolar disorder even if he has experienced only one of the extreme mood states, making diagnosis very challenging.

bipolar I: A type of bipolar disorder characterized by at least one full-blown manic episode that doctors can’t attribute to another cause, such as a medication or substance abuse. A bipolar I diagnosis doesn’t require an episode of major depression, although periods of mania often alternate with periods of depression.

bipolar II: A type of bipolar disorder characterized by at least one major depressive episode that doctors can’t attribute to another cause, along with one or more hypomanic episodes. The depression tends to be chronic and is usually more problematic than the hypomania. Some people with bipolar II develop a full manic episode, which changes the diagnosis to bipolar I.

bipolar NOS (not otherwise specified): A type of bipolar disorder listed in the fourth edition of Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) that’s characterized by hypomanic, manic, or depressive episodes that don’t fit in any of the other bipolar categories and can’t be ascribed to unipolar depression. See other specified bipolar and related disorders and unspecified bipolar and related disorders for the DSM-5 versions of this diagnosis.

catatonia: A state of profound lack of movement and language, often including odd or unusual physical and verbal responses to stimuli. Sometimes alternates with periods of agitation and overexcitement. Can be associated with bipolar disorder, unipolar depression, schizophrenia, and other psychiatric and medical conditions.

circadian rhythm: An individual’s biological pattern of sleep, wakefulness, and energy that plays out through the course of a day. Some studies show that irregularities in a person’s circadian rhythm can destabilize moods.

cognitive behavioral therapy (CBT): A therapy that works at the intersection between thoughts, feelings, and behavior. It is an active process; the therapist teaches about concepts and strategies, and the patient practices new skills outside of the sessions. Many studies show that CBT is effective for treating depression, anxiety, obsessive compulsive disorder, insomnia, PTSD, and some pain syndromes. Researchers are studying its use in other conditions as well.

comorbid: Any medical condition that presents along with and often independent from another condition. People who have bipolar disorder can have other comorbid conditions — such as attention deficit hyperactivity disorder (ADHD), alcoholism, or anxiety disorder — that complicate the diagnosis and treatment of bipolar disorder.

cyclothymia: Sometimes referred to as bipolar lite, a muted form of bipolar that nevertheless interferes with a person’s life. It involves multiple episodes of hypomania and depressive symptoms that don’t meet the criteria for mania or major depression. Symptoms must last for at least two years, (one year in children and teens) during which time there are no more than two symptom-free months.

decompensation: The return of symptoms that had been under control, relapse.

deep brain stimulation (DBS): Electronic stimulation of targeted areas of the brain that has been shown in some studies to reduce the symptoms of treatment resistant depression (TRD).

Diagnostic and Statistical Manual of Mental Disorders (DSM): A book that describes the criteria for diagnosing various mental illnesses and related conditions and that psychiatrists in the United States refer to when developing a diagnosis. DSM is similar to the International Classification of Diseases (ICD) used in most countries outside the United States.

differential diagnosis: The process of distinguishing between two or more diseases or conditions that feature identical or similar symptoms. A doctor commonly performs a differential diagnosis to rule out other possibilities.

dopamine: Often described as a feel-good neurotransmitter, dopamine is linked to feelings of pleasure and reward. It modulates attention, focus, and muscle movements, is involved in addiction, and is related to psychosis.

dysthymia: Chronic, low-level depression that’s commonly characterized by irritability and an inability to feel pleasure or joy. In DSM-5, now described as persistent depressive disorder.

electroconvulsive therapy (ECT): A medical procedure in which a low-level electrical current is applied to the brain to induce a mild seizure in order to treat severe depression. ECT is often successful in treating depression that doesn’t respond to medicine or therapy or when patients have had intolerable side effects with medicines or have medical conditions that prevent them from taking antidepressants. ECT can also be an effective treatment for mania and catatonia.

epigenetics: The study of the changes that affect the expression of genes but don’t change the genes themselves.

essential fatty acid (EFA): A healthy fat that the body uses for tissue development and other purposes and that must be obtained through diet. Omega-3 is a source of several EFAs that may be valuable in treating many health problems, including mood disorders.

euthymic: Moods considered to be in the normal range — not manic or depressive.

executive function: The ability to organize, sort, and manage internal and external stimuli and generate adaptive and effective responses. Many psychiatric disorders weaken executive functioning, often leading to impaired judgment and uninhibited speech or behavior.

expressed emotion: A term used by researchers to describe expressions of criticism or conflict that can have negative effects on people with mood disorders or other mental illness.

gamma-aminobutyric acid (GABA): An amino acid neurotransmitter that works mostly as an inhibitor or calming-down agent in the brain.

glutamate: A neurotransmitter that’s involved in revving up the central nervous system. Glutamate circuits may play a significant role in the development of mania and depression.

G-protein-linked receptors: These are also called metabotropic receptors, and are one of two main types of receptors found on cell surfaces, G-protein-linked receptors are part of a signal system that communicates between chemicals outside of the cell, including neurotransmitters such as serotonin. These chemicals attach to the G-protein-linked receptors, triggering specific reactions inside the cell These systems have been linked to the development of mood symptoms and to many of the medications used to treat bipolar disorder.

hypersexual: Having an excessive interest or involvement in sexual activity.

hyperthymic: A medical term for high energy, sometimes used to describe a personality profile that includes being highly extroverted, very active physically and mentally, highly confident, temperamental, stimulus seeking, and risk taking.

hypomania: An elevated mood that doesn’t qualify as full-blown mania but typically involves increased energy, less need for sleep, clarity of vision, and a strong creative drive. These changes are noticeable to others but don’t significantly impair daily function.

insight: A clear acceptance and understanding of a psychological disorder and the ability to objectively observe one’s own behaviors and attitudes that are characteristic of the disorder.

International Classification of Diseases (ICD): The diagnostic manual developed by the World Health Organization (WHO) and used in most countries outside the United States. The ICD includes a chapter on the Classification of Mental and Behavioral Disorders, which is similar to the Diagnostic and Statistical Manual of Mental Disorders (DSM) used in the United States.

interpersonal and social rhythm therapy (IPSRT): A therapy developed to maintain mood stability through strict scheduling, learning about personal roles, coping with transitions, developing healthy routines, increasing social contact, and resolving and preventing interpersonal problems.

maintenance dose: An amount of a prescription medication that’s intended to prevent the onset of symptoms rather than treat existing symptoms.

major depressive episode: An extreme low mood that lasts at least two weeks and is characterized by symptoms such as despair, fatigue, loss or increase in appetite, loss of interest in pleasurable activities, an increased need for sleep or inability to sleep, and thoughts of death or suicide.

mania: An extremely elevated mood typically characterized by euphoria, excessive energy, impulsivity, nervousness, impaired judgment, irritability, and a decreased need for sleep.

manic depression: Another name for bipolar disorder.

manic episode: A period of elevated mood, either euphoric or irritable, typically characterized by impulsivity, nervousness, impaired judgment, irritability, and a decreased need for sleep. The period must last at least one week (or shorter if it leads to hospitalization).

MAOI (monoamine oxidase inhibitor): A class of antidepressant medications that slow the action of monoamine oxidase, an enzyme responsible for breaking down dopamine, serotonin, and norepinephrine in the brain. Because of the strict diet changes needed when taking MAOIs, doctors typically prescribe them only if a person reacts poorly to other antidepressants.

mechanism of action: The way a medication acts on the biology or physiology of the brain to produce the desired effect.

mindfulness: A mental state of focusing on the present moment, creating active awareness of internal and external experiences, with full acceptance and without judgment. Mindfulness can be practiced in many ways, including particular types of meditation. Numerous scientific studies support the cognitive, emotional, and behavioral benefits of a variety of mindfulness strategies.

mood chart: A graph that shows the rise and fall of mood levels over time. Mood charts are very useful in predicting the onset of mood episodes and documenting the response to medications.

mood disorder: A psychiatric condition that results in persistently disrupted moods and/or mood regulation.

mood stabilizer: Strictly speaking, a medication that reduces frequency and/or severity of episodes of depression and/or mania. The term has become commonly, if inaccurately, associated with any medications that have antimanic effects or that reduce agitation.

neuroleptic: Another name for antipsychotics, neuroleptics led the charge in pharmacological treatment of mental illness in the 1950s and 1960s.

neuroleptic malignant syndrome: A potentially fatal but very rare side effect of antipsychotic medications that results in high temperature, muscle rigidity, and altered consciousness.

neurons: Cells that are part of the telecommunications network in the brain and other parts of the nervous system; they carry signals throughout the body.

neuroplasticity: The ability of the nervous system to adapt in response to internal and external stimuli or events. Some treatments for bipolar disorder appear to affect the capacity for change and growth in the nervous system.

neurotransmitter: A chemical that’s part of the communication systems between cells within the nervous system and from the nervous system to other parts of the body.

norepinephrine: Best known for its role in the fight-or-flight response, norepinephrine is a neurotransmitter that functions to regulate mood, anxiety, and memory.

off-label: A legal and legitimate use of a prescription medication to treat symptoms that the FDA (Food and Drug Administration) in the United States or comparable agencies in other countries didn’t officially approve it to treat.

omega-3: A source of several essential fatty acids that some experts believe are vital to the healthy development and function of the brain. Omega-3 is present in high concentration in cold-water ocean fish, including sardines, herring, and salmon; walnuts; flaxseed; and supplements.

other specified bipolar and related disorders: One of the DSM-5 categories of bipolar disorder, replacing bipolar disorder NOS in the DSMIV. This category relates to someone with most, but not all, of the symptoms of a specific type of bipolar; for example, all of the symptoms of hypomania but not lasting the necessary duration of four days, or lasting four days or more, but not having enough of the symptoms to meet full criteria.

phase delayed: The condition of having your daily rhythm out of sync with the rising and setting of the sun. Night owls and typically developing adolescents are considered to be phase delayed.

phototherapy: The use of light to stimulate mood changes.

presenting symptoms: Signs of discomfort that prompt a visit to a doctor.

pressured speech: Urgent, non-stop talking that’s difficult to interrupt. Pressured speech is a characteristic of hypomania and mania.

prodromal symptoms: Early signs that may indicate that a psychiatric disorder (including mania or depression) is developing.

prophylaxis: A fancy word for prevention. Doctors commonly prescribe a maintenance dose of a medication to prevent the onset of symptoms.

protein kinases: A group of secondary chemical messengers in the neurological system, including the brain, that trigger changes to proteins inside of cells.

psychiatrist: A physician who specializes in the biology and physiology of the brain. A psychiatrist’s role in treating bipolar includes diagnosis and medication prescription as well as patient education and psychotherapy.

psychoeducation: A type of therapy that consists primarily of educating those affected about the condition, its causes, and its treatment so they can more effectively manage the condition.

psychologist: A professional who specializes in brain development and function, thought processes, emotions, and behaviors. A psychologist can play a vital role in stabilizing moods by assessing brain functions and helping the sufferer adjust negative thoughts and thought processes, regulate emotional responses, and control self-destructive or otherwise maladaptive behaviors.

psychopharmacology: The study of the effects of medications on the brain.

psychosis: Brain malfunction that blurs the line between real and imaginary, often causing delusions, auditory hallucinations, and irrational fears.

psychotropic substance: Any chemical substance (usually a medicine) that affects mental functioning, emotions, or behavior.

rapid cycling: A state in which mood alternates between depression and mania more than four times in a year.

repetitive transcranial magnetic stimulation (rTMS): The application of strong, quick-changing magnetic fields to the brain to produce electrical fields indirectly. Researchers are studying it for use in treatment-resistant depression and other disorders.

schizoaffective disorder: A psychiatric disorder in which symptoms of bipolar disorder and schizophrenia are both present.

schizophrenia: A psychiatric disorder in which thought becomes dissociated from sensory input and emotions and is accompanied by hallucinations and delusional thinking. Thinking or cognitive skills are also often affected and day-to-day function can be severely impaired. Bipolar is sometimes misdiagnosed as schizophrenia.

seasonal affective disorder (SAD): A mood disorder that’s strongly linked to the change of seasons. People who have SAD commonly experience major depressive episodes in the winter months.

second messenger systems: Circuits that transmit signals within a brain cell rather than between brain cells.

Selective Serotonin and Norepinephrine Reuptake Inhibitor (SNRI): A class of antidepressant medications that prevent the brain from absorbing and breaking down the neurotransmitters norepinephrine and serotonin after their use. Whether this is the primary mechanism for reducing symptoms of depression is unclear.

Selective Serotonin Reuptake Inhibitor (SSRI): A class of antidepressant medications that prevent the brain from absorbing and breaking down the neurotransmitter serotonin after its use. Whether this is the primary mechanism for reducing symptoms of depression is unclear.

self-medicate: The attempt to stabilize moods by taking nonprescription chemical substances, including alcohol and marijuana, or by regulating doses of prescription medication without a doctor’s assistance.

serotonin: A neurotransmitter that’s a major part of the cellular circuits that regulate mood, anxiety, fear, sleep, body temperature, the rate at which your body releases certain hormones, and many other body and brain processes.

stigmatize: To brand someone as disgraceful or shameful.

stressor: Anything that places demands on your brain and body. Stressors are often thought of as negative, but exciting and positive events can also be stressful. Day-to-day life is full of little and big stressors, which the body and brain respond to and then return to baseline. Stress is a necessary and normal part of human function, but certain stressors may contribute to mood instability depending on various other factors.

support group: A group of patients and/or family members who meet to discuss and empower one another in the face of a common illness.

tardive dyskinesia: A condition — sometimes caused by the long-term use of neuroleptics — that results in abnormal, uncontrollable muscle movements, often in the mouth and face.

therapeutic level: The concentration of medicine in the bloodstream required for medication to be effective.

thyroid: A gland situated below the Adam’s apple that produces hormones that control growth, regulate many body functions, and influence moods.

treatment-resistant depression (TRD): Depression that doesn’t respond well to standard medical treatments, including medication.

tricyclic antidepressant: A class of medications that treat depression and limit the reuptake of the neurotransmitters serotonin and norepinephrine.

unipolar depression: A mood disorder characterized by episodes of major depression without symptoms of mania or hypomania.

unspecified bipolar and related disorders: A type of bipolar disorder listed in the fifth edition of Diagnostic and Statistical Manual of Mental Disorders (DSM-5) that’s characterized by hypomanic, manic, or depressive symptoms that cause problems in function, don’t fit into any of the other bipolar categories, and can’t be attributed to unipolar depression. See other specified bipolar and related disorders.

vagus nerve stimulation (VNS): Electronic brain stimulation through the vagus nerves in the neck that has some evidence of helping reduce the symptoms of treatment resistant depression (TRD).