Common Mental Health Terms

Psychosis is a mental experience in which a person has difficulty distinguishing what is real from what isn’t. It can happen with several mental-health or medical conditions, and sometimes with drugs, medications, or severe sleep deprivation.

A hallucination is a perception that seems real to a person but occurs without an external stimulus. In other words, someone sees, hears, smells, tastes, or feels something that isn't actually present.

Common types include:

• Auditory hallucinations: Hearing voices, music, or sounds that others don't hear.

• Visual hallucinations: Seeing people, objects, lights, or patterns that aren't there.

• Tactile hallucinations: Feeling sensations such as bugs crawling on the skin.

• Olfactory hallucinations: Smelling odors that have no external source.

• Gustatory hallucinations: Tasting something without a corresponding cause.

A delusion is a strongly held belief that remains fixed despite clear evidence that it is not true, and is not shared by the person's culture or community. The person experiences the belief as real, and simply presenting facts usually does not change it.

Unlike a hallucination, which is a false perception, a delusion is a false belief.

Some common types of delusions include:

• Persecutory delusions: Believing that others are spying on, following, or trying to harm you.

• Delusions of reference: Believing that ordinary events, television programs, songs, or strangers' conversations contain special messages meant specifically for you.

• Grandiose delusions: Believing you have exceptional abilities, wealth, power, or a special mission without evidence.

• Somatic delusions: Believing something is seriously wrong with your body despite medical evidence to the contrary.

• Jealous delusions: Believing a partner is unfaithful without convincing evidence.

• Erotomanic delusions: Believing another person—often someone famous or of higher status—is in love with you.

Mania and hypomania are periods of unusually elevated, expansive, or irritable mood accompanied by increased energy and activity. They exist on a spectrum, with mania being the more severe form.

Hypomania is a milder form of mania. During hypomania, a person may:

• Feel unusually energetic or euphoric.

• Need much less sleep without feeling tired.

• Talk more than usual or speak rapidly.

• Have racing thoughts.

• Be more confident or outgoing than usual.

• Be easily distracted.

• Take on many projects or activities.

• Engage in some risky behaviors (e.g., overspending or impulsive decisions).

A key feature is that hypomania does not cause major impairment in daily functioning. Some people even feel unusually productive or creative, although others may become irritable or make poor decisions.

Mania involves the same kinds of symptoms but they are more intense and significantly interfere with work, relationships, or safety. A person experiencing mania may:

• Have extremely elevated or irritable mood.

• Sleep very little for days and still feel energetic.

• Speak so rapidly that others struggle to interrupt.

• Jump quickly from one idea to another.

• Feel exceptionally powerful, important, or invincible.

• Make reckless financial, sexual, or business decisions.

• Become agitated or aggressive.

• Lose touch with reality by developing delusions or hallucinations.

Mania often requires urgent medical evaluation, and hospitalization may be needed if the person is at risk of harming themselves or others, or is unable to care for themselves.