Glossary: Depression

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Glossary

acetylcholine: A neurotransmitter that helps mediate learning and recollection.

adrenal glands: Two glands (one on top of each kidney) that secrete cortisol and norepinephrine.

amygdala: A region of the brain that processes emotionally charged memories.

antidepressant: A drug used to combat depression.

antipsychotic: A drug used to treat psychotic symptoms, such as disordered thoughts, delusions, or hallucinations.

brain imaging: A variety of technologies, such as computed tomography (CT), magnetic resonance imaging (MRI), functional MRI (fMRI), and positron emission tomography (PET), used to examine the structure or function of different regions of the brain.

cognitive behavioral therapy: A form of therapy that aims to correct ingrained patterns of negative thoughts and behaviors.

corticotropin-releasing hormone (CRH): A hormone secreted by the hypothalamus that helps rouse the body when a physical or emotional threat appears.

cortisol: A glucocorticoid, or steroid hormone, released by the adrenal glands and necessary to many basic body functions. This stress hormone is also involved in triggering the "fight or flight" response and similar responses.

dopamine: A neurotransmitter that affects movement and influences thought processes, possibly affecting motivation and reward.

gamma-aminobutyric acid (GABA): A neurotransmitter that may help quell anxiety.

glutamate: A neurotransmitter that may play a role in mood disorders and schizophrenia.

hippocampus: A portion of the brain that plays a central role in processing long-term memories and recollection.

hypomania: A mild mania.

hypothalamic-pituitary-adrenal (HPA) axis: A system that governs a multitude of hormonal activities in the body, including the body's responses to stress.

hypothalamus: A network of nerves above the brainstem that regulates the body's self-maintenance functions (such as blood pressure, temperature, and fluids). It receives signals from elsewhere in the body and secretes hormones that influence the production of other hormones, such as cortisol and thyroid hormone.

interpersonal therapy: A form of therapy that concentrates on illuminating and ironing out problems in current relationships.

monoamine oxidase inhibitors (MAOIs): Antidepressant medications that act by preventing the breakdown of the monoamines serotonin and norepinephrine.

neuron: A nerve cell.

neurotransmitters: Chemicals such as serotonin or norepinephrine that convey messages across the gap (synapse) between adjoining neurons.

norepinephrine: Sometimes called noradrenaline, this neurotransmitter plays a role in the regulation of mood, anxiety, and drive.

pituitary gland: A pea-sized organ located below the brain; it secretes adrenocorticotropic hormone.

psychodynamic therapy: A form of therapy that focuses on how life events, desires, and close relationships lead to conflict, symptoms such as anxiety or depression, and difficulty in managing life's tasks.

seasonal affective disorder (SAD): Sadness and depression that's brought on by a lack of exposure to sunlight. SAD usually appears in the fall or winter and subsides in the spring.

selective serotonin reuptake inhibitors (SSRIs): Antidepressants that block the reuptake of serotonin into the neurons that released it, leaving more serotonin available to nerve cell receptors.

serotonin: A neurotransmitter that helps regulate sleep and appetite, mediate moods, and inhibit pain.

thalamus: A central brain structure that relays sensory information.

tricyclic antidepressants (TCAs): A class of drugs that is thought to work by increasing the availability of norepinephrine and serotonin to nerve cell receptors.

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Last updated:	January 23, 2007