Dementia praecox is a disused psychiatric diagnosis that originally designated a chronic, deteriorating psychotic disorder characterized by rapid cognitive disintegration, usually beginning in the late teens or early adulthood. Over the years, the term dementia praecox was gradually replaced by the term schizophrenia, which initially had a meaning that included what is today considered the autism spectrum.
Psychosis is a condition of the mind that results in difficulties determining what is real and what is not real. Symptoms may include delusions and hallucinations, among other features. Additional symptoms are incoherent speech and behavior that is inappropriate for a given situation. There may also be sleep problems, social withdrawal, lack of motivation, and difficulties carrying out daily activities. Psychosis can have serious adverse outcomes.
Paranoia is an instinct or thought process that is believed to be heavily influenced by anxiety, suspicion, or fear, often to the point of delusion and irrationality. Paranoid thinking typically includes persecutory beliefs, or beliefs of conspiracy concerning a perceived threat towards oneself. Paranoia is distinct from phobias, which also involve irrational fear, but usually no blame.
A hallucination is a perception in the absence of an external stimulus that has the qualities of a real perception. Hallucinations are vivid, substantial, and are perceived to be located in external objective space. Hallucination is a combination of two conscious states of brain wakefulness and REM sleep. They are distinguishable from several related phenomena, such as dreaming, which does not involve wakefulness; pseudohallucination, which does not mimic real perception, and is accurately perceived as unreal; illusion, which involves distorted or misinterpreted real perception; and mental imagery, which does not mimic real perception, and is under voluntary control. Hallucinations also differ from "delusional perceptions", in which a correctly sensed and interpreted stimulus is given some additional significance. Many hallucinations happen also during sleep paralysis.
A delusion is a false fixed belief that is not amenable to change in light of conflicting evidence. As a pathology, it is distinct from a belief based on false or incomplete information, confabulation, dogma, illusion, hallucination, or some other misleading effects of perception, as individuals with those beliefs are able to change or readjust their beliefs upon reviewing the evidence. However:
Erotomania, also known as de Clérambault's Syndrome, is a relatively uncommon paranoid condition that is characterized by an individual's delusions of another person being infatuated with them. It is listed in the DSM-5 as a subtype of a delusional disorder. Commonly, the onset of erotomania is sudden, and the course is chronic.
Delusional disorder is a mental illness in which a person has delusions, but with no accompanying prominent hallucinations, thought disorder, mood disorder, or significant flattening of affect. Delusions are a specific symptom of psychosis. Delusions can be bizarre or non-bizarre in content; non-bizarre delusions are fixed false beliefs that involve situations that could occur in real life, such as being harmed or poisoned. Apart from their delusion or delusions, people with delusional disorder may continue to socialize and function in a normal manner and their behavior does not necessarily generally seem odd. However, the preoccupation with delusional ideas can be disruptive to their overall lives.
The mental status examination (MSE) is an important part of the clinical assessment process in neurological and psychiatric practice. It is a structured way of observing and describing a patient's psychological functioning at a given point in time, under the domains of appearance, attitude, behavior, mood and affect, speech, thought process, thought content, perception, cognition, insight, and judgment. There are some minor variations in the subdivision of the MSE and the sequence and names of MSE domains.
Disorganized schizophrenia, or hebephrenia, was a subtype of schizophrenia prior to 2013. Subtypes of schizophrenia were no longer recognized as separate conditions in the DSM 5, published in 2013. The disorder is no longer listed in the 11th revision of the International Classification of Diseases (ICD-11).
Myxedema psychosis is a relatively uncommon consequence of hypothyroidism, such as in Hashimoto's thyroiditis or in patients who have had the thyroid surgically removed and are not taking thyroxine. A chronically under-active thyroid can lead to slowly progressive dementia, delirium, and in extreme cases to hallucinations, coma, or psychosis, particularly in the elderly.
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.
Paraphrenia is a mental disorder characterized by an organized system of paranoid delusions with or without hallucinations and without deterioration of intellect or personality.
In parapsychology, an apparitional experience is an anomalous experience characterized by the apparent perception of either a living being or an inanimate object without there being any material stimulus for such a perception.
Brief psychotic disorder — according to the classifications of mental disorders DSM-IV-TR and DSM-5 — is a psychotic condition involving the sudden onset of at least one psychotic symptom lasting 1 day to 1 month, often accompanied by emotional turmoil. Remission of all symptoms is complete with patients returning to the previous level of functioning. It may follow a period of extreme stress including the loss of a loved one. Most patients with this condition under DSM-5 would be classified as having acute and transient psychotic disorders under ICD-10. Prior to DSM-IV, this condition was called "brief reactive psychosis." This condition may or may not be recurrent, and it should not be caused by another condition.
Folie à deux, additionally known as shared psychosis or shared delusional disorder (SDD), is a rare psychiatric syndrome in which symptoms of a delusional belief, and sometimes hallucinations, are transmitted from one individual to another. The same syndrome shared by more than two people may be called folie à trois ('three') or quatre ('four'); and further, folie en famille or even folie à plusieurs.
The word schizophrenia was coined by the Swiss psychiatrist Eugen Bleuler in 1908, and was intended to describe the separation of function between personality, thinking, memory, and perception. He introduced the term on 24 April 1908 in a lecture given at a psychiatric conference in Berlin and in a publication that same year. Bleuler later expanded his new disease concept into a monograph in 1911, which was finally translated into English in 1950.
Childhood schizophrenia is similar in characteristics of schizophrenia that develops at a later age, but has an onset before the age of 13 years, and is more difficult to diagnose. Schizophrenia is characterized by positive symptoms that can include hallucinations, delusions, and disorganized speech; negative symptoms, such as blunted affect and avolition and apathy, and a number of cognitive impairments. Differential diagnosis is problematic since several other neurodevelopmental disorders, including autism spectrum disorder, language disorder, and attention deficit hyperactivity disorder, also have signs and symptoms similar to childhood-onset schizophrenia.
Unitary psychosis (Einheitspsychose) refers to the 19th-century belief prevalent in German psychiatry until the era of Emil Kraepelin that all forms of psychosis were surface variations of a single underlying disease process. According to this model, there were no distinct disease entities in psychiatry but only varieties of a single universal madness and the boundaries between these variants were fluid. The prevalence of the concept in Germany during the mid-19th century can be understood in terms of a general resistance to Cartesian dualism and faculty psychology as expressed in Naturphilosophie and other Romantic doctrines that emphasised the unity of body, mind and spirit.
Cotard's syndrome, also known as Cotard's delusion or walking corpse syndrome, is a rare mental disorder in which the affected person holds the delusional belief that they are dead, do not exist, are putrefying, or have lost their blood or internal organs. Statistical analysis of a hundred-patient cohort indicated that denial of self-existence is present in 45% of the cases of Cotard's syndrome; the other 55% of the patients presented with delusions of immortality.
Simple-type schizophrenia is a sub-type of schizophrenia included in the International Classification of Diseases (ICD-10), in which it is classified as a mental and behaviour disorder. It is not included in the current Diagnostic and Statistical Manual of Mental Disorders (DSM-5) or the upcoming ICD-11, effective 1 January 2022. Simple-type schizophrenia is characterized by negative ("deficit") symptoms, such as avolition, apathy, anhedonia, reduced affect display, lack of initiative, lack of motivation, low activity; with absence of hallucinations or delusions of any kind.
