This glossary covers terms found in the psychiatric literature; the word origins are primarily Greek, but there are also Latin, French, German, and English terms. Many of these terms refer to expressions dating from the early days of psychiatry in Europe; some are deprecated, and thus are of historic interest.

A abreaction Abreaction is a process of vividly reliving repressed memories and emotions related to a past event.Hales E and Yudofsky JA, eds, The American Psychiatric Press Textbook of Psychiatry, Washington, DC: American Psychiatric Publishing, Inc., 2003 Sigmund Freud used hypnosis to rid his patients of pathological memories through abreaction.

abulia Aboulia or Abulia, in neurology, refers to a lack of will or initiative. The individual is unable to act or make decisions independently. The condition may range from subtle to overwhelming in severity.

achromatopsia Achromatopsia is a term referring to or acquired agnosia for color. This term includes color blindness. Achromatopsia is a condition characterized by a partial or total absence of color vision. People with complete achromatopsia cannot perceive any colors; they see only black, white, and shades of gray. Incomplete achromatopsia is a milder form of the condition that allows some color discrimination.

Achromatopsia also involves other problems with vision, including an increased sensitivity to light and glare (photophobia), involuntary back-and-forth eye movements (nystagmus), and significantly reduced sharpness of vision (low visual acuity). Affected individuals can also have farsightedness (hyperopia) or, less commonly, nearsightedness (myopia). These vision problems develop in the first few months of life.

Achromatopsia is different from the more common forms of color vision deficiency (also called color blindness), in which people can perceive color but have difficulty distinguishing between certain colors, such as red and green.

affect illusion Mild illusions or misperceptions associated with changes in mood; e.g. mistaking a shadow for the presence of a person, perceiving movement in peripheral when there is none.

akataphasia Akataphasia (Kraepelin 1896) refers to a syntactic disturbance of speech resulting from dissolution of logical ordering of thoughts. It manifests as rambling speech. Compare Derailment.

akathisia

Akathisia refers to a subjective feeling of restlessness in the lower limbs that is related to abnormal activity in the extrapyramidal system in the brain, often due to antipsychotic medication. It tends to manifest as an inability to sit still.

alexithymia

Alexithymia refers to an inability to identify and describe emotions in the self.

Alice in Wonderland experience

In Alice in Wonderland experience, individuals perceive objects (including animals and other humans, or parts of humans, animals, or objects) as appearing substantially smaller than in reality. Generally, the object appears far away or extremely close at the same time. An alternate term for this is somaesthetic aura. Also see

alogia

Literally, this term means "not having words". The term may refer to either "poverty of speech" or "poverty of thought". In the former, speech, though adequate in verbiage, conveys very little information and may consist of stock phrases or vague references. In poverty of thought, by contrast, there is a far-reaching impoverishment of the entire thinking of the individual, who, as a result, says very little. It is typically a negative symptom of schizophrenia, although it may also be seen in advanced dementia.

amenomania Amenomania (compound of Latin amoenus, "cheerful"; and Greek μανία, "madness") is a disused psychiatric diagnosis.

amok

The phrase "running amok" describes the behavior of an individual who is very agitated and may be at danger of causing harm to themselves or others. The syndrome of "Amok" is found in the DSM-IV TR.

anhedonia

Anhedonia refers to an inability to experience pleasure, and may be described as a feeling of emotional emptiness. It can be a negative symptom of schizophrenia. It also may be seen in severe depressive states and schizoid personality disorder.

anosognosia

Anosognosia is a condition in which a person who has a certain disability seems unaware of the existence of their disability. is a subtype of anosognosia in which the person with hemiplegia neglects one half of their body.

Anton's syndrome

Anton syndrome, occasionally known as Anton-Babinski syndrome, is a form of cortical blindness in which the individual denies the visual impairment. The individual may attempt to walk, bumping into objects and injuring himself. Anton syndrome is caused by damaging the occipital lobes bilaterally or from disrupting the pathway from the primary visual cortex into the visual association cortex.

anwesenheit Anwesenheit refers to the false perception of an unfamiliar presence. It is commonly associated with periods of grief, schizophrenia and other emotional disturbances.

apophanous perception This is an alternate term for delusional perception. It is one of the Schneiderian first rank symptoms and is defined as a true perception, to which an individual attributes a false meaning.

aphemia Aphemia is the alternate term for mutism. Mutism is absence of speech with apparently normal level of consciousness. Mutism can be dissociative (hysterical) in which an individual (commonly a child or adolescent) stops speaking at once without involvement of any neurological or physical contributing factor; or it can be elective (selective) in which a child does not speak at all in certain situations (such as in school) but speaks well in other conditions (like at home or at play). A rare cause of mutism is akinetic mutism which results due to a lesion around the third ventricle of the brain.

apperception Apperception is a normal phenomenon and refers to the ability to understand sensory inputs in their context, to interpret them and to incorporate them into experience. Failure of apperception is seen in delirious states.

astasia-abasia

Astasia-abasia is a form of psychogenic gait disturbance in which gait becomes impaired in the absence of any neurological or physical pathology. The person usually walks in a bizarre manner. They stagger and appear as if going to fall, but always manage to catch hold of something in time. Sometimes these people cannot even stand, but on the other hand they are well able to move their legs while lying down or sitting. Often associated with conversion disorder or somatization disorder.

asyndesis Asyndesis means loosening of association. A milder form of derailment of thought, it is marked by the individual leaping from topic to topic which have only the most tenuous, if any, connection with each other. This is in contrast with , whereby the individual's successive ideas may be linked and "understandable" to the listener. See also and term introduced by (Cameron).

autism

From aut = "self" and -ism = "state or orientation". Originally, Eugen Bleuler used this term to describe schizophrenia. In general, it refers to any (pathological) tendency to be self-absorbed to such a degree that the feelings, thoughts and desires of a person are governed by their internal apprehension of the world and not by an external reality shared with others.

Today the term is used most often to refer to a specific developmental syndrome (see autism spectrum).

autistic thinking

autistic thinking is an outdated term for egocentric thought processes that have little or no relation to consensus reality. The term does not accurately describe the thinking styles of autistic people.

autochthonous delusion

Jaspers defined this as a delusion arising without apparent cause. For example, suddenly, without apparent cause, having the delusional belief that one is an alien.

autokabalesis

Autokabalesis is a term for committing suicide by jumping from a very high place.

automatic obedience Automatic obedience is an exaggerated co-operation with an examiner's request, as if the individual were an "automaton" robotically obeying a command. It is often a sign of catatonia.

automatism

Automatisms are sequences of activity that occur without conscious control. They may be simple and repetitive (tic-like) or complex, and are usually natural-looking but purposeless. Automatic behavior is not usually recalled afterwards.

autoscopy Autoscopy is the reduplicative hallucination of "seeing one's own body from the outside" while still maintaining an egocentric visuo-spatial perspective. Autoscopy is sometimes used synonymously with out-of-body experience.

avolition

Avolition is an inability to initiate and complete goal-directed behavior. It can sometimes be misinterpreted as laziness, but it is actually a negative symptom of schizophrenia.

B belle indifference Belle indifference or la belle indifférence is characterized by a lack of concern and feeling of indifference about a disability or symptom. It can be seen in conversion disorder.

bouffée délirante Bouffée délirante is a French term used in the past for acute and transient psychotic disorders (F23 in ICD-10). In DSM-IV, it is described as "brief psychotic disorder" (298.8). The symptoms usually have an acute onset and reach their peak within two weeks. The symptoms start resolving in a few weeks and complete recovery usually occurs within two or three months.

brain fag syndrome

Brain fag syndrome is an example of a culture-bound syndrome. "Brain fag" was once a common term for mental exhaustion. Today, the syndrome describes students (predominantly males, particularly in West Africa) experiencing symptoms including somatic, sleep-related and cognitive complaints, head and neck pains, difficulty in concentrating and retaining information, and eye pain.

brain fog Synonym of .

bruxism

Bruxism refers to teeth grinding behavior that is usually seen in children.

C Capgras' syndrome or illusion des sosies

In Capgras syndrome, the individual feels that a person familiar to them, usually a family member, has been replaced by an imposter. This is a type of delusion that can be experienced as part of schizophrenia. Capgras syndrome and several other related disorders are referred to as "delusional misidentification syndrome".

catalepsy

Catalepsy is the term for catatonic rigidity of the limbs which often results in abnormal posturing for long intervals.

cataplexy

Cataplexy refers to a sudden loss of muscle tone and is commonly precipitated by a strong emotional response.

catatonia

Catatonia involves a significant psychomotor disturbance, which can occur as catalepsy, stupor, excessive purposeless motor activity, extreme negativism (seemingly motiveless resistance to movement), mutism, echolalia (imitating speech), or echopraxia (imitating movements). There is a catatonic subtype of schizophrenia.

cerea flexibilitas

Cerea flexibilitas, meaning "waxy flexibility", refers to people allowing themselves to be placed in postures by others, and then maintaining those postures for long periods even if they are obviously uncomfortable. It is characterized by an individual's movements having the feeling of a plastic resistance, as if the person were made of wax. This occurs in catatonic schizophrenia, and a person with this condition can have their limbs placed in fixed positions as if the person were in fact made from wax.

chorea

Chorea refers to erratic involuntary movements. The term comes from the Greek word "choreia" or "dance" since usually large groups of muscles are involved simulating dance-like movements.

circumstantial speech

Circumstantial thinking, or circumstantial speech, refers to a person being unable to answer a question without giving excessive, unnecessary detail. This differs from tangential thinking, in that the person does eventually return to the original point, circling back on-topic.

clang association