A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

A
Abreaction An emotional release or discharge after recalling a painful experience that has been repressed as it was not intolerable consciously.
Abulia  A lack of will or motivation.
Acalculia The loss of ability to engage in arithmetics.
Acetylcholine A neurotransmitter in the brain, which helps to regulate memory, and in the peripheral nervous system, where it affects the actions of skeletal and smooth muscle.
Actualization The realization of one's full potential - intellectual, psychological, physical, etc.
Adrenergic This refers to neuronal or neurologic activity caused by neurotransmitters such as epinephrine, norepinephrine, and dopamine.
Affect This word is used to described observable feeling state (emotion). Common examples of affect are sadness, fear, joy, and anger. Types of affect include: euthymic, irritable, constricted; blunted; flat; inappropriate, and labile.
Affective disorders Refers to disorders of mood.  Examples Depressed Mood, Bipolar Disorder
Agitation (psychomotor agitation) Excessive motor activity that accompanies and is associated with a feeling of inner tension. The activity is usually nonproductive and repetitious and consists of such behavior as pacing, fidgeting, wringing of the hands, pulling of clothes, and inability to sit still.
Agnosia Failure to recognize or identify familiar objects despite intact sensory function; This may be seen in dementia of various types. 
Agoraphobia Anxiety about being in places or situations in which escape might be difficut or embarrassing or in which help may not be available should a panic attack occur. The fears typically relate to venturing into the open, of leaving the familiar setting of one's home, or of being in a crowd, standing in line, or traveling in a car or train.
Akathisia Complaints of restlessness accompanied by movements such as fidgeting of the legs, rocking from foot to foot, pacing, or inability to sit or stand. Usually associated with the use of older antipsychotics
Akinetic mutism A state of apparent alertness with following eye movements but no speech or voluntary motor responses.
alexia Loss of a previously intact ability to grasp the meaning of written or printed words and sentences.
Alexithymia difficulty in describing or recognizing one's own emotions, a limited fantasy life, and general constriction in affective life.
Algophobia Fear of pain.
Alogia An impoverishment in thinking that is inferred from observing speech and language behavior.
Ambivalence The coexistence of contradictory emotions, attitudes, ideas, or desires with respect to a particular person, object, or situation.
Amnesia Loss of memory. Types of amnesia include: anterograde Loss of memory of events that occur after the onset of the etiological condition. retrograde Loss of memory of events that occurred before the onset of the etiological condition.
Anankastic personality  obsessive-compulsive personality.
Anhedonia Inability to experience pleasure from activities that usually produce pleasurable feelings.
Anosognosia The apparent unawareness of or failure to recognize one's own functional defect (e.g., hemiplegia, hemianopsia).
Anxiety The apprehensive anticipation of future danger or misfortune accompanied by a feeling symptoms of tension.
apathy Lack of feeling, emotion, interest, or concern.
Aphasia An impairment in the understanding or transmission of ideas by language in any of its forms--reading, writing, or speaking.
apraxia Inability to carry out previously learned skilled motor activities despite intact comprehension and motor function; this may be seen in dementia.
ataxia Partial or complete loss of coordination of voluntary muscular movement.
auditory hallucination A hallucination involving the perception of sound, most commonly of voices. The sound or voice is perceived as coming from outside the head.
automatism Automatic and apparently undirected nonpurposeful behavior that is not consciously controlled. 
avolition An inability to initiate and persist in goal-directed activities.

B
bestiality Zoophilia; sexual relations between a human being and an animal. See also paraphilia.
bradykinesia Neurologic condition characterized by a generalized slowness of motor activity.
Broca's aphasia Loss of the ability to comprehend language coupled with production of inappropriate language.
bruxism Grinding of the teeth, occurs unconsciously while awake or during stage 2 sleep. May be secondary to anxiety, tension, or dental problems.

C 
Capgras' syndrome The delusion that others, or the self, have been replaced by imposters.
catalepsy Waxy flexibility--rigid maintenance of a body position over an extended period of time.
cataplexy Episodes of sudden bilateral loss of muscle tone resulting in the individual collapsing, often in association with intense emotions such as laughter, anger, fear, or surprise.
catatonic behavior Marked motor abnormalities including motoric immobility (i.e., catalepsy or stupor), certain types of excessive motor activity (apparently purposeless agitation not influenced by external stimuli), extreme negativism (apparent motiveless resistance to instructions or attempts to be moved) or mutism, posturing or stereotyped movements, and echolalia or echopraxia
circumstantiality Pattern of speech that is indirect and delayed in reaching its goal because of excessive or irrelevant details.
cognitive Pertaining to thoughts or thinking. Cognitive disorders are disorders of thinking, for example, schizophrenia.
comorbidity The simultaneous appearance of two or more illnesses. 
compulsion Repetitive ritualistic behaviour such as hand washing. The person feels driven to perform such actions, even though the behaviours are recognized to be excessive or unreasonable.
concrete thinking Thinking characterized by immediate experience, rather than abstractions.
confabulation Fabrication of stories in response to questions about situations or events that are not recalled.
constructional apraxia An acquired difficulty in drawing two-dimensional objects or forms, or in producing or copying three-dimensional arrangements of forms or shapes.
countertransference The therapist's emotional reactions to the patient.
conversion symptom A loss of, or alteration in, voluntary motor or sensory functioning suggesting a neurological or general medical condition. The symptom is not fully explained by a neurological or general medical condition and is not intentionally produced.

D
defense mechanism Automatic psychological process that protects the individual against anxiety and from awareness of internal or external stressors or dangers. Defense mechanisms mediate the individual's reaction to emotional conflicts and to external stressors e.g., projection, splitting, acting out suppression and denial. These are sub-conscious in nature
déjà vu A paramnesia consisting of the sensation or illusion that one is seeing what one has seen before
delusion A false belief based on incorrect inference about external reality that is firmly sustained despite what almost everyone else believes and despite proof or evidence to the contrary. The belief is not one ordinarily accepted by other members of the person's culture or subculture (e.g., it is not an article of religious faith).
delusional jealousy The delusion that one's sexual partner is unfaithful. Usually associated with alcoholism.
delusion of reference A delusion whose theme is that events, objects, or other persons in one's immediate environment have a particular and unusual significance.
denial A defense mechanism where certain information is not accessed by the conscious mind. For example “denying” that one has a serious illness like HIV.
depersonalization An alteration in the perception or experience of the self so that one feels detached from, and as if one is an outside body (e.g., feeling like one is in a dream).
derailment ("loosening of associations") A pattern of speech in which a person's ideas slip off one track onto another that is completely unrelated or only obliquely related.
derealization An alteration in the perception or experience of the external world so that it seems strange or unreal (e.g., people may seem unfamiliar or mechanical).
Dhat Syndrome Culturally bound syndrome of the Indian sub-continent where patients suffer from anxiety relating to loss of semen from the body.
disorientation Confusion about the time of day, date, or season (time), where one is (place), or who one is (person).
Dysdiadochokinesia  The inability to perform rapid alternating movements of one or more of the extremities.  This task is sometimes requested by physicians of patients during physical examinations to determine if there exists neurological problems.
dysphoric mood An unpleasant mood, such as sadness, anxiety, or irritability.
displacement A defense mechanism, in which emotions, ideas, or wishes are transferred from their original object to a more acceptable substitute; often used to allay anxiety.
dissociation A disruption in the usually integrated functions of consciousness, memory, identity, or perception of the environment.
DSM-IV  fourth edition of the Diagnostic and Statistical  Manual of Mental Disorders, published by the American Psychiatric Association, Washington DC (1994).
dysarthria Imperfect articulation of speech due to disturbances of muscular control or incoordination.
dyskinesia Distortion of voluntary movements with involuntary muscular activity.
dyslexia Inability or difficulty in reading, including word-blindness and a tendency to reverse letters and words in reading and writing.
dyssomnia Primary disorders of sleep or wakefulness characterized by insomnia or hypersomnia as the major presenting symptom. Dyssomnias are disorders of the amount, quality, or timing of sleep.
dystonia Disordered tone of muscles.

E 
echolalia The pathological, and apparently senseless repetition (echoing) of a word or phrase just spoken by another person. echolalia Parrot-like repetition of overheard words or fragments of speech.
echopraxia Repetition by imitation of the movements of another. The action is not a willed or voluntary one and has a semiautomatic and uncontrollable quality.
ego In psychoanalytic theory, one of the three major divisions in the model of the psychic apparatus, the others being the id and the superego. Ego (reality) serves to mediate between the demands of primitive instinctual drives (the id) & internalized parental and social prohibitions (the superego).
ego-dystonic Referring to aspects of a person's behavior, thoughts, and attitudes that are viewed by the self as repugnant or inconsistent with the total personality.
elevated mood An exaggerated feeling of well-being, or euphoria or elation. A person with elevated mood may describe feeling "high," "ecstatic," "on top of the world," or "up in the clouds."
Erotomania  (de Clérambault's syndrome) - patient holds the delusional belief that someone else, usually of a higher social or professional status, is in love with them.
euthymic Mood in the "normal" range, which implies the absence of depressed or elevated mood.
expansive mood Lack of restraint in expressing one's feelings, frequently with an overvaluation of one's significance or importance. irritable Easily annoyed and provoked to anger.

F 
flashback A recurrence of a memory, feeling, or perceptual experience from the past.
flat affect An affect type that indicates the absence of signs of affective expression.
flight of ideas A nearly continuous flow of accelerated speech with abrupt changes from topic to topic that are usually based on understandable associations, distracting stimuli, or plays on words.
flooding (implosion) A behaviour therapy procedure for phobias in which anxiety producers are presented in intense forms, either in imagination or in real life. The presentations, which act as desensitizers, are continued until the stimuli no longer produce disabling anxiety.
folie à deux A shared psychotic disorder between 2 people, usually people who are mutually dependent upon each other.
formal thought disorder An inexact term referring to a disturbance in the form of thinking rather than to abnormality of content. See blocking; loosening of associations; poverty of speech.
formication The tactile hallucination or illusion that insects are crawling on the body or under the skin.
frotteurism  recurrent, intense sexual urges involving touching and rubbing against a nonconsenting person; common sites in which such activities take place are crowded trains, buses, and elevators.

G 
gender dysphoria A persistent aversion toward some or all of those physical characteristics or social roles that connote one's own biological sex.
gender identity A person's inner conviction of being male or female.
gender role Attitudes, patterns of behavior, and personality attributes defined by the culture in which the person lives as stereotypically "masculine" or "feminine" social roles.
grandiosity An inflated appraisal of one's worth, power, knowledge, importance, or identity. When extreme, grandiosity may be of delusional proportions.
gustatory hallucination A hallucination involving the perception of taste.

H 
hallucination A sensory perception that occurs without external stimulation of the relevant sensory organ. Hallucinations should be distinguished from illusions, in which an actual external stimulus is misperceived or misinterpreted.
hyperacusis Inordinate sensitivity to sounds; it may be on an emotional or an organic basis.
hypersomnia Excessive sleepiness.
Hypnagogic Hallucination hallucinations just before falling asleep that are of no pathological significance.
Hypnopompic Hallucination hallucinations just before waking from sleep that are of no pathological significance

I
ICD-10 tenth revision of the International Classification of Diseases published by the World Health Organization, Geneva (1992)
ideas of reference Incorrect interpretations of casual incidents and external events as having direct reference to oneself. For example getting personal messages from tv or newspapers.
illusion A misperception or misinterpretation of a real external stimulus.
inappropriate affect An affect type that represents an unusual affective expression that does not match with the content of what is being said or thought.
insomnia A subjective complaint of difficulty falling or staying asleep or poor sleep quality. Types of insomnia include:
intellectualization A mental mechanism in which the person engages in excessive abstract thinking to avoid confrontation with conflicts or disturbing feelings.

J
Jamais vu - illusion of failure to recognise a familiar situation

K
Klinefelter's syndrome Chromosomal defect in males in which there is an extra X chromosome; manifestations may include underdeveloped testes, physical feminization, sterility, and mental retardation.
koro  A culture specific syndrome of China involving fear of retraction of penis into abdomen with the belief that this will lead to death.

L
la belle indifférence Seen in certain patients with conversion disorders who show an inappropriate lack of concern about their disabilities
labile affect An affect type that indicates abnormal sudden rapid shifts in affect.
latah A culture specific syndrome of Southeast Asia involving startle-induced disorganization, hypersuggestibility, automatic obedience, and echopraxia.
libido The psychic drive or energy usually associated with the sexual instinct.

M 
masochism Pleasure derived from physical or psychological pain inflicted on oneself either by oneself or by others.
mental retardation A major group of disorders of infancy, childhood, or adolescence characterized by intellectual functioning that is significantly below average (IQ of 70 or below). Different levels of severity are recognized: an IQ level of 50/55 to 70 is Mild; an IQ level of 35/40 to 50/55 is Moderate; an IQ level of 20/25 to 35/40 is Severe; an IQ level below 20/25 is Profound.
mood A pervasive and sustained emotion. In contrast to affect, which refers to more fluctuating changes in emotional "weather," mood refers to a more pervasive and sustained emotional "climate." 
mood-congruent psychotic features Delusions or hallucinations whose content is entirely consistent with the typical themes of a depressed or manic mood.

N
negative symptoms Most commonly refers to a group of symptoms characteristic of schizophrenia that include loss of fluency and spontaneity of verbal expression, impaired ability to focus or sustain attention on a particular task, difficulty in initiating or following through on tasks, impaired ability to experience pleasure to form emotional attachment to others, and blunted affect. 
neologism In psychiatry, a new word or condensed combination of several words coined by a person to express a highly complex idea not readily understood by others; seen in schizophrenia and organic mental disorders.
Neuroleptics Medications with an antipsychotic effect that are used in the treatment of schizophrenia and other serious mental illnesses. (Also known as antipsychotics.)
nihilistic delusion The delusion of nonexistence of the self or part of the self, or of some object in external reality.

O
Obsession Recurrent and persistent thought, impulse, or image experienced as intrusive and distressing. Recognized as being excessive and unreasonable even though it is the product of one's mind. This thought, impulse, or image cannot be expunged by logic or reasoning.
Oedipus complex Attachment of the child to the parent of the opposite sex, accompanied by envious and aggressive feelings toward the parent of the same sex.
olfactory hallucination A hallucination involving the perception of smell.
orientation Awareness of one's self in relation to time, place, and person.
overvalued idea An unreasonable and sustained belief that is maintained with less than delusional intensity (i.e., the person is able to acknowledge the possibility that the belief may not be true). The belief is not one that is ordinarily accepted by other members of the person's culture or subculture

P 
panic attacks Discrete periods of sudden onset of intense apprehension, fearfulness, or terror, often associated with feelings of impending doom. During these attacks there are symptoms such as shortness of breath or smothering sensations; palpitations, pounding heart, or accelerated heart rate; chest pain or discomfort; choking; and fear of going crazy or losing control. Exposure to a situational trigger is not invariably associated with it.
paranoia Ideation, of less than delusional proportions, involving suspiciousness or the belief that one is being harassed, persecuted, or unfairly treated.
parasomnia Abnormal behavior or physiological events occurring during sleep or sleep-wake transitions.
Parkinsonism A group of symptoms including loss of movement, a lack of facial expression, stiff gait when walking, tremor, or stooped posture. These symptoms are sometimes side-effects of older typical antipsychotic medications.
persecutory delusion  A delusion in which the central theme is that one (or someone to whom one is close) is being attacked or conspired against.
perseveration Tendency to emit the same verbal or motor response again and again to varied stimuli.
personality Enduring patterns of perceiving, relating to, and thinking about the environment and oneself. Personality traits are prominent aspects of personality that are exhibited in a wide range of important social and personal contexts. Only when personality traits are inflexible and maladaptive and cause either significant functional impairment or subjective distress do they constitute a Personality Disorder.
phobia A persistent, irrational fear of a specific object, activity, or situation (the phobic stimulus) that results in a compelling desire to avoid it.
piblokto  A culture specific syndrome of Eskimos involving attacks of screaming, crying, and running naked through the snow
pressured speech Speech that is increased in amount, accelerated, and difficult or impossible to interrupt.
prodrome An early or premonitory sign or symptom of a disorder
projection A defense mechanism in which what is emotionally unacceptable in the self is unconsciously rejected and attributed (projected) to others.
projective identification projection of one or more parts of the self or of the internal object into another person (such as the mother). What is projected may be an intolerable, painful, or dangerous part of the self or object (the bad object). It may also be a valued aspect of the self or object (the good object) that is projected into the other person for safekeeping. The other person is changed by the projection and is dealt with as though he or she is in fact characterized by the aspects of the self that have been projected.
prosopagnosia Inability to recognize familiar faces that is not explained by defective visual acuity or reduced consciousness or alertness.
pseudocyesis Included in DSM-IV as one of the somatoform disorders. It is characterized by a false belief of being pregnant and by the occurrence of signs of being pregnant, such as abdominal enlargement, breast engorgement, and labour pains.
pseudodementia A syndrome in which dementia is mimicked or caricatured by depression.
psychotic delusions or prominent hallucinations, with the hallucinations occurring in the absence of insight into their pathological nature. A slightly less restrictive definition would also include prominent hallucinations that the individual realizes are hallucinatory experiences. Also includes other positive symptoms of Schizophrenia (i.e., disorganized speech, grossly disorganized or catatonic behavior).
Psychotherapy Therapy involving psychological instead of medical treatment of mental disorders. It can include supportive dialogue, counseling, and cognitive behavioral approaches to achieve a thinking-feeling reorganization.
Psychotropic medication Medication that affects thought processes or feeling states and used in the treatment of mental disorders.

R 
rationalization A defense mechanism, in which an individual attempts to justify or make consciously tolerable by plausible means, feelings or behavior that otherwise would be intolerable.
reaction formation A defense mechanism, in which a person adopts affects, ideas, and behaviours that are the opposites of impulses.
regression Partial or symbolic return to earlier patterns of reacting or thinking.
reinforcement The strengthening of a response by reward or avoidance of punishment.

S  
Schizoaffective Disorder A condition that includes symptoms of both schizophrenia and affective (mood) disorder.
Schizoid Socially isolated, withdrawn, having few friends and social relationships, resembling the personality features of schizophrenia, but in a less severe form; no loss of touch with reality.
Schizophrenia A common type of psychosis characterized by hallucinations and/or delusions, personality changes, withdrawal, and serious thought and speech disturbances.
secondary gain The external gain derived from any illness, such as personal attention and service, monetary gains, disability benefits, and release from unpleasant responsibilities. See also primary gain.
separation anxiety disorder A disorder with onset before the age of 18 consisting of inappropriate anxiety concerning separation from home or from persons to whom the child is attached.
sick role An identity adopted by an individual as a "patient" that specifies a set of expected behaviours.
simultanagnosia Inability to comprehend more than one element of a visual scene at the same time or to integrate the parts into a whole
sleep terror disorder One of the parasomnias, characterized by panic and confusion when abruptly awakening from sleep.
somatic delusion  A delusion whose main content pertains to the appearance or functioning of one's body.
somatic hallucination A hallucination involving the perception of a physical experience localized within the body (such as a feeling of electricity).
Stockholm syndrome A kidnapping or terrorist hostage identifies with and has sympathy for his or her captors on whom he or she is dependent for survival.
stupor A state of unresponsiveness with immobility and mutism
sublimation A defense mechanism by which instinctual drives, consciously unacceptable, are diverted into personally and socially acceptable channels.
substitution A defense mechanism, by which an unattainable or unacceptable goal, emotion, or object is replaced by one that is more attainable or acceptable.
synesthesia A condition in which a sensory experience associated with one modality occurs when another modality is stimulated, for example, a sound produces the sensation of a particular color.
systematic desensitization A behaviour therapy procedure widely used to modify behaviours associated with phobias. The procedure involves the construction of a hierarchy of anxiety-producing stimuli by the subject, and gradual presentation of the stimuli until they no longer produce anxiety.

T 
tactile hallucination A hallucination involving the perception of being touched or of something being under one's skin.
therapeutic window A well-defined range of blood levels associated with optimal clinical response to antidepressant drugs, such as Lithium. Levels above or below that range are associated with a poor response.
thought broadcasting The delusion that one's thoughts are being broadcast out loud so that they can be perceived by others.
thought insertion The delusion that certain of one's thoughts are not one's own, but rather are inserted into one's mind.
tic An involuntary, sudden, rapid, recurrent, nonrhythmic, stereotyped motor movement or vocalization.
Tranquilizer A medicine that produces a calming effect. The so-called major tranquilizers are antipsychotics while the minor tranquilizers are benzos like valium (diazepam)
transference In feelings of the patient towards the physician.
transitional object An object, other than the mother, selected by an infant between 4 and 18 months of age for self-soothing and anxiety-reduction.
transsexualism Severe gender dysphoria, coupled with a persistent desire for the physical characteristics and social roles that connote the opposite biological sex.
transvestism Sexual pleasure derived from dressing or masquerading in the clothing of the opposite sex, with the strong wish to appear as a member of the opposite sex.

V
verbigeration Stereotyped and seemingly meaningless repetition of words or sentences.
visual hallucination A hallucination involving sight, which may consist of formed images, such as of people, or of unformed images, such as flashes of light.
voyeurism Peeping; one of the paraphilias, characterized by marked distress over, or acting on, urges to observe unsuspecting people, usually strangers, who are naked or in the process of disrobing, or who are engaging in sexual activity.

W
Wernicke's aphasia Loss of the ability to comprehend language coupled with production of inappropriate language.
windigo A culture specific syndrome of Canadians involving delusions of being possessed by a cannibal-istic monster (windigo), attacks of agitated depression, oral sadistic fears and impulses.
word salad A mixture of words and phrases that lack comprehensive meaning or logical coherence; commonly seen in schizophrenic states.

Z 
zoophilia One of the paraphilias, characterized by urges to indulge in sexual activity that involves animals.