A thought disorder (TD) is a disturbance in cognition which affects language, thought and communication.[1][2] Psychiatric and psychological glossaries in 2015 and 2017 identified thought disorders as encompassing poverty of ideas, neologisms, paralogia (a reasoning disorder characterized by expression of illogical or delusional thoughts), word salad, and delusions - all disturbances of thought content and form. Two specific terms have been suggested — content thought disorder (CTD) and formal thought disorder (FTD). CTD has been defined as a thought disturbance characterized by multiple fragmented delusions, and the term thought disorder is often used to refer to an FTD:[3] a disruption of the form (or structure) of thought.[4] Also known as disorganized thinking, FTD results in disorganized speech and is recognized as a major feature of schizophrenia and other psychoses[5][6] (including mood disorders, dementia, mania, and neurological diseases).[7][5][8] Disorganized speech leads to an inference of disorganized thought.[9] Thought disorders include derailment,[10]pressured speech, poverty of speech, tangentiality, verbigeration, and thought blocking.[8] One of the first known cases of thought disorders, or specifically OCD as it is known today, was in 1691. John Moore, who was a bishop, had a speech in front of Queen Mary II, about "religious melancholy."[11]
Formal thought disorder affects the form (rather than of the content) of thought.[12] Unlike hallucinations and delusions, it is an observable, objective sign of psychosis.[12] FTD is a common core symptom of a psychotic disorder, and may be seen as a marker of severity and as an indicator of prognosis.[8][13] It reflects a cluster of cognitive, linguistic, and affective disturbances that have generated research interest in the fields of cognitive neuroscience, neurolinguistics, and psychiatry.[8]
Eugen Bleuler, who named schizophrenia, said that TD was its defining characteristic.[14] Disturbances of thinking and speech, such as clanging or echolalia, may also be present in Tourette syndrome;[15] other symptoms may be found in delirium.[16] A clinical difference exists between these two groups. Patients with psychoses are less likely to show awareness or concern about disordered thinking, and those with other disorders are aware and concerned about not being able to think clearly.[17]
Content thought disorder
Content thought disorder is a thought disturbance in which a person experiences multiple, fragmented delusions, typically a feature of schizophrenia and some other mental disorders which include obsessive-compulsive disorder and mania.[18][19] At the core of thought content disorder are abnormal beliefs and convictions (after taking the person's culture and background into consideration) ranging from overvalued ideas to fixed delusions.[20] These beliefs and delusions are typically non-specific diagnostically,[21] even if some delusions are more prevalent in one disorder than another.[22]
Neurotypical thought—consisting of awareness, concerns, beliefs, preoccupations, wishes, fantasies, imagination, and concepts—can be illogical, and can contain contradictory beliefs and prejudices or biases.[23][24] Individuals vary considerably, and a person's thinking may also shift from time to time.[25]
Content thought disorder is not limited to delusions. Other possible abnormalities include suicidal, violent, and homicidal ideas[26] and:[27][20]
Preoccupation: centering thought on a particular idea in association with a strong affection
Obsession: a persistent thought, idea, or image which is intrusive or inappropriate, and distressing or upsetting
Compulsive behavior: the need to perform an act persistently and repetitively (without it necessarily leading to a reward or pleasure) to reduce distress
Magical thinking: belief that one's thoughts alone can bring about effects in the world, or that thinking something corresponds with doing that thing
Overvalued ideas: false or exaggerated belief held with conviction, but without delusional intensity
Phobias: irrational fears of objects or circumstances[28][29]
Erotomania: belief that someone is in love with oneself
Grandiose delusions: belief that one is the greatest, strongest, fastest, richest, or the most intelligent person ever
Persecutory delusion: belief that the person, or someone to whom the person is close, is being malevolently treated in some way
Ideas and delusions of reference: belief that insignificant remarks, coincidental events, or innocuous objects in one's environment have personal meaning or significance
Thought broadcasting: belief that others can hear (or are aware of) one's thoughts
Thought insertion: belief that one's thoughts are not one's own, but belong to someone else and have been inserted into one's mind[31]
Thought withdrawal: belief that thoughts have been "taken out" of one's mind, and one has no power over this
Influence: belief that other people (or external agents) are covertly exerting power over oneself
Outside control: belief that outside forces are controlling one's thoughts, feelings, and actions[32]
Infidelity: belief that a partner is cheating on oneself
Somatic: belief that one has a disease or medical condition
Nihilistic: belief that the mind, the body, the world at large, or parts thereof no longer exist
Formal thought disorder
Formal thought disorder (FTD) is also known as disorganized speech. Evidence of disorganized thinking, it is a hallmark feature of schizophrenia.[4][6] FTD, a disorder of the form (rather than content) of thought, encompasses hallucinations and delusions[12] and is an observable sign of psychosis. A common, core symptom of psychosis, it may be seen as a marker of severity and a predictor of prognosis.[8][13] FTD reflects a cluster of cognitive, linguistic, and affective disturbances which has generated research interest from the fields of cognitive neuroscience, neurolinguistics, and psychiatry.[8]
It can be subdivided into clusters of positive and negative symptoms and objective (rather than subjective) symptoms.[13] On the scale of positive and negative symptoms, they have been grouped into positive formal thought disorder (posFTD) and negative formal thought disorder (negFTD).[13][12] Positive subtypes were pressure of speech, tangentiality, derailment, incoherence, and illogicality;[13] negative subtypes were poverty of speech and poverty of content.[12][13] The two groups were posited to be at either end of a spectrum of normal speech, but later studies showed them to be poorly correlated.[12] A comprehensive measure of FTD is the Thought and Language Disorder (TALD) Scale.[33] The Kiddie Formal Thought Disorder Rating Scale (K-FTDS) can be used to assess the presence of formal thought disorder in children and their childhood. Although it is very extensive and time-consuming, its results are in great detail and reliable.[34]
Nancy Andreasen preferred to identify TDs as thought-language-communication disorders (TLC disorders).[35] Up to seven domains of FTD have been described on the Thought, Language, Communication (TLC) Scale, with most of the variance accounted for by two or three domains.[12] Some TLC disorders are more suggestive of severe disorder, and are listed with the first 11 items.[35]
Diagnoses
The DSM V categorizes FTD as "a psychotic symptom, manifested as bizarre speech and communication." FTD may include incoherence, peculiar words, disconnected ideas, or a lack of unprompted content expected from normal speech.[36]Clinical psychologists typically assess FTD by initiating an exploratory conversation with patients and observing the patient's verbal responses.[37]
FTD is often used to establish a diagnosis of schizophrenia; in cross-sectional studies, 27 to 80 percent of patients with schizophrenia present with FTD. A hallmark feature of schizophrenia, it is also widespread amongst other psychiatric disorders; up to 60 percent of those with schizoaffective disorder and 53 percent of those with clinical depression demonstrate FTD, suggesting that it is not exclusive to schizophrenia. About six percent of healthy subjects exhibit a mild form of FTD.[38]
The characteristics of FTD vary amongst disorders. A number of studies indicate that FTD in mania is marked by irrelevant intrusions and pronounced combinatory thinking, usually with a playfulness and flippancy absent from patients with schizophrenia.[39][40][41] The FTD present in patients with schizophrenia was characterized by disorganization, neologism, and fluid thinking, and confusion with word-finding difficulty.[41]
There is limited data on the longitudinal course of FTD.[42] The most comprehensive longitudinal study of FTD by 2023 found a distinction in the longitudinal course of thought-disorder symptoms between schizophrenia and other psychotic disorders. The study also found an association between pre-index assessments[clarification needed] of social, work and educational functioning and the longitudinal course of FTD.[43]
Possible causes
Several theories have been developed to explain the causes of formal thought disorder. It has been proposed that FTD relates to neurocognition via semantic memory.[44]Semantic network impairment in people with schizophrenia—measured by the difference between fluency (e.g. the number of animals' names produced in 60 seconds) and phonological fluency (e.g. the number of words beginning with "F" produced in 60 seconds)—predicts the severity of formal thought disorder, suggesting that verbal information (through semantic priming) is unavailable.[44] Other hypotheses include working memory deficit (being confused about what has already been said in a conversation) and attentional focus.[44]
FTD in schizophrenia has been found to be associated with structural and functional abnormalities in the language network, where structural studies have found bilateral grey matter deficits; deficits in the bilateral inferior frontal gyrus, bilateral inferior parietal lobule and bilateral superior temporal gyrus are FTD correlates.[38] Other studies did not find an association between FTD and structural aberrations of the language network, however, and regions not included in the language network have been associated with FTD.[38] Future research is needed to clarify whether there is an association with FTD in schizophrenia and neural abnormalities in the language network.[38]
Transmitter systems which might cause FTD have also been investigated. Studies have found that glutamate dysfunction, due to a rarefaction of glutamatergic synapses in the superior temporal gyrus in patients with schizophrenia, is a major cause of positive FTD.[38]
The heritability of FTD has been demonstrated in a number of family and twin studies. Imaging genetics studies, using a semantic verbal-fluency task performed by the participants during functional MRI scanning, revealed that alleles linked to glutamatergic transmission contribute to functional aberrations in typical language-related brain areas.[38] FTD is not solely genetically determined, however; environmental influences, such as allusive thinking in parents during childhood, and environmental risk factors for schizophrenia (including childhood abuse, migration, social isolation, and cannabis use) also contribute to the pathophysiology of FTD.[45]
The origins of FTD have been theorised from a social-learning perspective. Singer and Wynne said that familial communication patterns play a key role in shaping the development of FTD; dysfunctional social interactions undermine a child's development of cohesive, stable mental representations of the world, increasing their risk of developing FTD.[46]
Treatments
Antipsychotic medication is often used to treat FTD. Although the vast majority of studies of the efficacy of antipsychotic treatment do not report effects on syndromes or symptoms, six older studies report the effects of antipsychotic treatment on FTD.[47][48][49][50][51][52] These studies and clinical experience indicate that antipsychotics are often an effective treatment for patients with positive or negative FTD, but not all patients respond to them.
Cognitive behavioural therapy (CBT) is another treatment for FTD, but its effectiveness has not been well-studied.[38] Large randomised controlled trials evaluating the effectiveness of CBT for treating psychosis often exclude individuals with severe FTD because it reduces the therapeutic alliance required by the therapy.[53] However, provisional evidence suggests that FTD may not preclude the effectiveness of CBT.[53] Kircher and colleagues have suggested that the following methods should be used in CBT for patients with FTD:[38]
Practise structuring, summarising, and feedback methods
Repeat and clarify the core issues and main emotions that the patient is trying to communicate
Gently encourage patients to clarify what they are trying to communicate
Ask patients to clearly state their communication goal
Ask patients to slow down and explain how one point leads to another
Help patients identify the links between ideas
Identify the main affect linked to the thought disorder
Normalise problems with thinking
Signs and symptoms
Language abnormalities exist in the general population, and do not necessarily indicate a condition.[54] They can occur in schizophrenia and other disorders (such as mania or depression), or in anyone who may be tired or stressed.[1][55] To distinguish thought disorder, patterns of speech, severity of symptoms, their frequency, and any resulting functional impairment can be considered.[35]
Thirty symptoms (or features) of TD have been described, including:[56][12]
Alogia: A poverty of speech in amount or content, it is classified as a negative symptom of schizophrenia. When further classifying symptoms, poverty of speech content (little meaningful content with a normal amount of speech) is a disorganization symptom.[57] Under SANS, thought blocking is considered a part of alogia, and so is increased latency in response.[58]
Thought blocking (also known as deprivation of thought and obstructive thought): An abrupt stop in the middle of a train of thought which may not be able to be continued.[59]
Circumstantial speech (also known as circumstantial thinking):[60] An inability to answer a question without excessive, unnecessary detail.[61] This differs from tangential thinking in that the person does eventually return to the original point. A patient may answer the question "How have you been sleeping lately?" with "Oh, I go to bed early, so I can get plenty of rest. I like to listen to music or read before bed. Right now I'm reading a good mystery. Maybe I'll write a mystery someday. But it isn't helping, reading I mean. I have been getting only 2 or 3 hours of sleep at night."[62]
Clanging: An instance where ideas are related only by similar or rhyming sounds rather than actual meaning.[63][64] This may be heard as excessive rhyming or alliteration ("Many moldy mushrooms merge out of the mildewy mud on Mondays", or "I heard the bell. Well, hell, then I fell"). It is most commonly seen in the manic phase of bipolar disorder, although it is also often observed in patients with schizophrenia and schizoaffective disorder.
Derailment (also known as loose association and knight's move thinking):[60] Thought frequently moves from one idea to another which is obliquely related or unrelated, often appearing in speech but also in writing[65] ("The next day when I'd be going out you know, I took control, like uh, I put bleach on my hair in California"),[66]
Distractible speech: In mid-speech, the subject is changed in response to a nearby stimulus ("Then I left San Francisco and moved to... Where did you get that tie?")[66][67]
Evasion: The next logical idea in a sequence is replaced with another idea closely (but not accurately or appropriately) related to it; also known as paralogia and perverted logic.[72][73]
Flight of ideas:[60] A form of FTD marked by abrupt leaps from one topic to another, possibly with discernible links between successive ideas, perhaps governed by similarities between subjects or by rhyming, puns, wordplay, or innocuous environmental stimuli (such as the sound of birds chirping). It is most characteristic of the manic phase of bipolar disorder.[63]
Illogicality:[74] Conclusions are reached which do not follow logically (non sequiturs or faulty inferences). "Do you think this will fit in the box?" is answered with, "Well of course; it's brown, isn't it?"
Incoherence (word salad):[60] Speech which is unintelligible because the individual words are real, but the manner in which they are strung together results in gibberish.[63] The question "Why do people comb their hair?" elicits a response like "Because it makes a twirl in life, my box is broken help me blue elephant. Isn't lettuce brave? I like electrons, hello please!"
Neologisms:[60] Completely new words (or phrases) whose origins and meanings are usually unrecognizable ("I got so angry I picked up a dish and threw it at the geshinker").[75] They may also involve elisions of two words which are similar in meaning or sound.[76] Although neologisms may refer to words formed incorrectly whose origins are understandable (such as "headshoe" for "hat"), these can be more clearly referred to as word approximations.[77]
Overinclusion:[68] The failure to eliminate ineffective, inappropriate, irrelevant, extraneous details associated with a particular stimulus.[29][78]
Perseveration:[68] Persistent repetition of words or ideas, even when another person tries to change the subject.[63] ("It's great to be here in Nevada, Nevada, Nevada, Nevada, Nevada.") It may also involve repeatedly giving the same answer to different questions ("Is your name Mary?" "Yes." "Are you in the hospital?" "Yes." "Are you a table?" "Yes"). Perseveration can include palilalia and logoclonia, and may indicate an organic brain disease such as Parkinson's disease.[68]
Phonemic paraphasia: Mispronunciation; syllables out of sequence ("I slipped on the lice and broke my arm").[79]
Pressured speech:[80] Rapid speech without pauses, which is difficult to interrupt.
Referential thinking: Viewing innocuous stimuli as having a specific meaning for the self[81] ("What's the time?" "It's 7 o'clock. That's my problem").
Semantic paraphasia: Substitution of inappropriate words ("I slipped on the coat, on the ice I mean, and broke my book").[82]
Stilted speech:[83] Speech characterized by words or phrases which are flowery, excessive, and pompous[63] ("The attorney comported himself indecorously").
Tangential speech: Wandering from the topic and never returning to it, or providing requested information[63][84] ("Where are you from?" "My dog is from England. They have good fish and chips there. Fish breathe through gills").
Verbigeration:[85] Meaningless, stereotyped repetition of words or phrases which replace understandable speech; seen in schizophrenia.[85][86]
Terminology
Psychiatric and psychological glossaries in 2015 and 2017 defined thought disorder' as disturbed thinking or cognition which affects communication, language, or thought content including poverty of ideas, neologisms, paralogia, word salad, and delusions[7][19] (disturbances of thought content and form), and suggested the more-specific terms content thought disorder (CTD) and formal thought disorder (FTD).[2] CTD was defined as a TD characterized by multiple fragmented delusions,[18][19] and FTD was defined as a disturbance in the form or structure of thinking.[87][88] The 2013 DSM-5 only used the term FTD, primarily as a synonym for disorganized thinking and speech.[89] This contrasts with the 1992 ICD-10 (which only used the word "thought disorder", always accompanied with "delusion" and "hallucination")[90] and a 2002 medical dictionary which generally defined thought disorders similarly to the psychiatric glossaries[91] and used the word in other entries as the ICD-10 did.[92]
A 2017 psychiatric text describing thought disorder as a "disorganization syndrome" in the context of schizophrenia:
"Thought disorder" here refers to disorganization of the form of thought and not content. An older use of the term "thought disorder" included the phenomena of delusions and sometimes hallucinations, but this is confusing and ignores the clear differences in the relationships between symptoms that have become apparent over the past 30 years. Delusions and hallucinations should be identified as psychotic symptoms, and thought disorder should be taken to mean formal thought disorders or a disorder of verbal cognition.
—Phenomenology of Schizophrenia (2017), THE SYMPTOMS OF SCHIZOPHRENIA[83]
The text said that some clinicians use the term "formal thought disorder" broadly, referring to abnormalities in thought form with psychotic cognitive signs or symptoms,[93] and studies of cognition and subsyndromes in schizophrenia may refer to FTD as conceptual disorganization or disorganization factor.[83]
Some disagree:
Unfortunately, "thought disorder" is often involved rather loosely to refer to both FTD and delusional content. For the sake of clarity, the unqualified use of the phrase "thought disorder" should be discarded from psychiatric communication. Even the designation "formal thought disorder" covers too wide a territory. It should always be made clear whether one is referring to derailment or loose associations, flight of ideas, or circumstantiality.
—The Mental Status Examination, The Medical Basis of Psychiatry (2016)[94]
Course, diagnosis, and prognosis
It was believed that TD occurred only in schizophrenia, but later findings indicate that it may occur in other psychiatric conditions (including mania) and in people without mental illness.[95] Not all people with schizophrenia have a TD; the condition is not specific to the disease.[96]
When defining thought-disorder subtypes and classifying them as positive or negative symptoms, Nancy Andreasen found[96] that different subtypes of TD occur at different frequencies in those with mania, depression, and schizophrenia. People with mania have pressured speech as the most prominent symptom, and have rates of derailment, tangentiality, and incoherence as prominent as in those with schizophrenia. They are likelier to have pressured speech, distractibility, and circumstantiality.[96][97]
People with schizophrenia have more negative TD, including poverty of speech and poverty of content of speech, but also have relatively high rates of some positive TD.[96] Derailment, loss of goal, poverty of content of speech, tangentiality and illogicality are particularly characteristic of schizophrenia.[98] People with depression have relatively-fewer TDs; the most prominent are poverty of speech, poverty of content of speech, and circumstantiality. Andreasen noted the diagnostic usefulness of dividing the symptoms into subtypes; negative TDs without full affective symptoms suggest schizophrenia.[96][97]
She also cited the prognostic value of negative-positive-symptom divisions. In manic patients, most TDs resolve six months after evaluation; this suggests that TDs in mania, although as severe as in schizophrenia, tend to improve.[96] In people with schizophrenia, however, negative TDs remain after six months and sometimes worsen; positive TDs somewhat improve. A negative TD is a good predictor of some outcomes; patients with prominent negative TDs are worse in social functioning six months later.[96] More prominent negative symptoms generally suggest a worse outcome; however, some people may do well, respond to medication, and have normal brain function. Positive symptoms vary similarly.[99]
A prominent TD at illness onset suggests a worse prognosis, including:[83]
illness begins earlier
increased risk of hospitalization
decreased functional outcomes
increased disability rates
increased inappropriate social behaviors
TD which is unresponsive to treatment predicts a worse illness course.[83] In schizophrenia, TD severity tends to be more stable than hallucinations and delusions. Prominent TDs are more unlikely to diminish in middle age, compared with positive symptoms.[83] Less-severe TD may occur during the prodromal and residual periods of schizophrenia.[100] Treatment for thought disorder may include psychotherapy, such as cognitive behavior therapy (CBT), and psychotropic medications.[101]
The DSM-5 includes delusions, hallucinations, disorganized thought process (formal thought disorder), and disorganized or abnormal motor behavior (including catatonia) as key symptoms of psychosis.[6] Schizophrenia-spectrum disorders such as schizoaffective disorder and schizophreniform disorder typically consist of prominent hallucinations, delusions and FTD; the latter presents as severely disorganized, bizarre, and catatonic behavior.[4][6] Psychotic disorders due to medical conditions and substance use typically consist of delusions and hallucinations.[6][102] The rarer delusional disorder and shared psychotic disorder typically present with persistent delusions.[102] FTDs are commonly found in schizophrenia and mood disorders, with poverty of speech content more common in schizophrenia.[103]
Psychoses such as schizophrenia and bipolar mania are distinguishable from malingering, when an individual fakes illness for other gains, by clinical presentations; malingerers feign thought content with no irregularities in form such as derailment or looseness of association.[104] Negative symptoms, including alogia, may be absent, and chronic thought disorder is typically distressing.[104]
Autism spectrum disorders (ASD) whose diagnosis requires the onset of symptoms before three years of age can be distinguished from early-onset schizophrenia; schizophrenia under age 10 is extremely rare, and ASD patients do not display FTDs.[105] However, it has been suggested that individuals with ASD display language disturbances like those found in schizophrenia; a 2008 study found that children and adolescents with ASD showed significantly more illogical thinking and loose associations than control subjects.[106] The illogical thinking was related to cognitive functioning and executive control; the loose associations were related to communication symptoms and parent reports of stress and anxiety.[106]
Rorschach tests have been useful for assessing TD in disturbed patients.[107][1] A series of inkblots are shown, and patient responses are analyzed to determine disturbances of thought.[1] The nature of the assessment offers insight into the cognitive processes of another, and how they respond to equivocal stimuli.[108]Hermann Rorschach developed this test to diagnose schizophrenia after realizing that people with schizophrenia gave drastically different interpretations of Klecksographie inkblots from others whose thought processes were considered normal,[109] and it has become one of the most widely used assessment tools for diagnosing TDs.[1]
The Thought Disorder Index (TDI), also known as the Delta Index, was developed to help further determine the severity of TD in verbal responses.[1] TDI scores are primarily derived from verbally-expressed interpretations of the Rorschach test, but TDI can also be used with other verbal samples (including the Wechsler Adult Intelligence Scale).[1] TDI has a twenty-three-category scoring index; each category scores the level of severity on a scale from 0–1, with .25 being mild and 1.00 being most severe (.25, .50, .75, 1.00).[1]
Criticism
TD has been criticized as being based on circular or incoherent definitions.[110][need quotation to verify] Symptoms of TD are inferred from disordered speech, based on the assumption that disordered speech arises from disordered thought. Although TD is typically associated with psychosis, similar phenomena can appear in different disorders and leading to misdiagnosis.[111]
A criticism related to the separation of symptoms of schizophrenia into negative or positive symptoms, including TD, is that it oversimplifies the complexity of TD and its relationship to other positive symptoms.[112]Factor analysis has found that negative symptoms tend to correlate with one another, but positive symptoms tend to separate into two groups.[112] The three clusters became known as negative symptoms, psychotic symptoms, and disorganization symptoms.[99] Alogia, a TD traditionally classified as a negative symptom, can be separated into two types: poverty of speech content as (a disorganization symptom) and poverty of speech, response latency, and thought blocking (negative symptoms).[113] Positive-negative-symptom diametrics, however, may enable a more accurate characterization of schizophrenia.[114]
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.
Schizophrenia is a brain disorder characterized by reoccurring episodes of psychosis that are correlated with a general misperception of reality. Other common signs include hallucinations, delusions, disorganized thinking, social withdrawal, and flat affect. Symptoms develop gradually and typically begin during young adulthood and are never resolved. There is no objective diagnostic test; diagnosis is based on observed behavior, a psychiatric history that includes the person's reported experiences, and reports of others familiar with the person. For a diagnosis of schizophrenia, the described symptoms need to have been present for at least six months or one month. Many people with schizophrenia have other mental disorders, especially substance use disorders, depressive disorders, anxiety disorders, and obsessive–compulsive disorder.
Clanging is a symptom of mental disorders, primarily found in patients with schizophrenia and bipolar disorder. This symptom is also referred to as association chaining, and sometimes, glossomania.
Schizoaffective disorder is a mental disorder characterized by abnormal thought processes and an unstable mood. This diagnosis requires symptoms of both schizophrenia and a mood disorder: either bipolar disorder or depression. The main criterion is the presence of psychotic symptoms for at least two weeks without any mood symptoms. Schizoaffective disorder can often be misdiagnosed when the correct diagnosis may be psychotic depression, bipolar I disorder, schizophreniform disorder, or schizophrenia. This is a problem as treatment and prognosis differ greatly for most of these diagnoses.
Delusional disorder, traditionally synonymous with paranoia, 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.
In psychology, alogia is poor thinking inferred from speech and language usage. There may be a general lack of additional, unprompted content seen in normal speech, so replies to questions may be brief and concrete, with less spontaneous speech. This is termed poverty of speech or laconic speech. The amount of speech may be normal but conveys little information because it is vague, empty, stereotyped, overconcrete, overabstract, or repetitive. This is termed poverty of content or poverty of content of speech. Under Scale for the Assessment of Negative Symptoms used in clinical research, thought blocking is considered a part of alogia, and so is increased latency in response.
Kurt Schneider was a German psychiatrist known largely for his writing on the diagnosis and understanding of schizophrenia, as well as personality disorders then known as psychopathic personalities.
Stimulant psychosis is a mental disorder characterized by psychotic symptoms. It involves and typically occurs following an overdose or several day 'binge' on psychostimulants; however, one study reported occurrences at regularly prescribed doses in approximately 0.1% of individuals within the first several weeks after starting amphetamine or methylphenidate therapy. Methamphetamine psychosis, or long-term effects of stimulant use in the brain, depend upon genetics and may persist for some time.
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).
Thought broadcasting is a type of delusional condition in which the affected person believes that others can hear their inner thoughts, despite a clear lack of evidence. The person may believe that either those nearby can perceive their thoughts or that they are being transmitted via mediums such as television, radio or the internet. Different people can experience thought broadcasting in different ways. Thought broadcasting is most commonly found among people that have a psychotic disorder, specifically schizophrenia.
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.
Schizophreniform disorder is a mental disorder diagnosed when symptoms of schizophrenia are present for a significant portion of time, but signs of disturbance are not present for the full six months required for the diagnosis of schizophrenia.
Grandiose delusions (GD), also known as delusions of grandeur or expansive delusions, and also informally known in Japan as eighth-grade syndrome or chūnibyō, are a subtype of delusion that occur in patients with a wide range of psychiatric disorders, including two-thirds of patients in a manic state of bipolar disorder, half of those with schizophrenia, patients with the grandiose subtype of delusional disorder, frequently as a comorbid condition in narcissistic personality disorder, and a substantial portion of those with substance abuse disorders. GDs are characterized by fantastical beliefs that one is famous, omnipotent, wealthy, or otherwise very powerful. The delusions are generally fantastic and typically have a religious, science fictional, or supernatural theme. There is a relative lack of research into GD, in contrast to persecutory delusions and auditory hallucinations. Around 10% of healthy people experience grandiose thoughts at some point in their lives but do not meet full criteria for a diagnosis of GD.
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.
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.
The diagnosis of schizophrenia, a psychotic disorder, is based on criteria in either the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, or the World Health Organization's International Classification of Diseases (ICD). Clinical assessment of schizophrenia is carried out by a mental health professional based on observed behavior, reported experiences, and reports of others familiar with the person. Diagnosis is usually made by a psychiatrist. Associated symptoms occur along a continuum in the population and must reach a certain severity and level of impairment before a diagnosis is made. Schizophrenia has a prevalence rate of 0.3-0.7% in the United States
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.
The relationship between religion and schizophrenia is of particular interest to psychiatrists because of the similarities between religious experiences and psychotic episodes; religious experiences often involve auditory and/or visual phenomena, and those with schizophrenia commonly report hallucinations and delusions that may resemble the events found within a religious experience. In general, religion has been found to have "both a protective and a risk increasing effect" for schizophrenia.
Hyperreligiosity is a psychiatric disturbance in which a person experiences intense religious beliefs or episodes that interfere with normal functioning. Hyperreligiosity generally includes abnormal beliefs and a focus on religious content or even atheistic content, which interferes with work and social functioning. Hyperreligiosity may occur in a variety of disorders including epilepsy, psychotic disorders and frontotemporal lobar degeneration. Hyperreligiosity is a symptom of Geschwind syndrome, which is associated with temporal lobe epilepsy.
1 2 3 Kaplan & Sadock's Comprehensive Textbook of Psychiatry (2017), Appendix B: Glossary of Psychiatry and Psychology Terms. "thought disorder Any disturbance of thinking that affects language, communication, or thought content; the hallmark feature of schizophrenia. Manifestations range from simple blocking and mild circumstantiality to profound loosening of associations, incoherence, and delusions; characterized by a failure to follow semantic and syntactic rules that is inconsistent with the person's education, intelligence, or cultural background."
1 2 3 4 5 6 Bora E, Yalincetin B, Akdede BB, Alptekin K (July 2019). "Neurocognitive and linguistic correlates of positive and negative formal thought disorder: A meta-analysis". Schizophrenia Research. 209: 2–11. doi:10.1016/j.schres.2019.05.025. PMID31153670. S2CID167221363.
↑ Colman, A. M. (2001) Oxford Dictionary of Psychology, Oxford University Press. ISBN0-19-860761-X
↑ Barrera A, McKenna PJ, Berrios GE (2009). "Formal thought disorder, neuropsychology and insight in schizophrenia". Psychopathology. 42 (4): 264–9. doi:10.1159/000224150. PMID19521143. S2CID26079338.
↑ Houghtalen RP, Mcintyre JS (2017). "7.1 Psychiatric Interview, History, and Mental Status Examination of the Adult Patient". In Sadock VA, Sadock BJ, Ruiz P (eds.). Kaplan & Sadock's Comprehensive Textbook of Psychiatry (10thed.). Wolters Kluwer. Table 7.1-5. Elements of the Mental Status Examination with Examples of Abnormal Findings. ISBN978-1-4511-0047-1. Thought content: obsession, delusion, magical thinking, overvalued ideas, ideas of reference or influence, persecutory ideas.
1 2 Sadock BJ (2017). "7.2 Outline for a Psychiatric Examination". In Sadock VA, Sadock BJ, Ruiz P (eds.). Kaplan & Sadock's Comprehensive Textbook of Psychiatry (10thed.). Wolters Kluwer. MENTAL STATUS, Table 7.2–1. Common Questions for the Psychiatric History and Mental Status. ISBN978-1-4511-0047-1. Thought content: Delusions— persecutory (paranoid), grandiose, infidelity, somatic, sensory, thought broadcasting, thought insertion, ideas of reference, ideas of unreality, phobias, obsessions, compulsions, ambivalence, autism, dereism, blocking, suicidal or homicidal preoccupation, conflicts, nihilistic ideas, hypochondriasis, depersonalization, derealization, flight of ideas, idé fixe, magical thinking, neologisms.
1 2 Akiskal HS (2016). "1 The Mental Status Examination". In Fatemi SH, Clayton PJ (eds.). The Medical Basis of Psychiatry (4thed.). New York: Springer Science+Business Media. 1.5.5. Speech and Thought., pp. 8–10. doi:10.1007/978-1-4939-2528-5. ISBN978-1-4939-2528-5.
"This form of thought is most characteristic of mania and tends to be overinclusive, with difficulty in excluding irrelevant, extraneous details from the association."
1 2 Thought Disorder (2016), 25.2. Definition., pp. 497–498.citedFish FJ (1962). Schizophrenia. Bristol, England: Bright.
↑ Fatemi SH, Folsom TD (2016). "6 Schizophrenia". In Fatemi SH, Clayton PJ (eds.). The Medical Basis of Psychiatry (4thed.). New York: Springer Science+Business Media. 6.6. Clinical Findings, 6.6.2. Mental Status Examination in a Subject with Schizophrenia, 6.6.2.5. Thought Form and Content, p. 103. doi:10.1007/978-1-4939-2528-5. ISBN978-1-4939-2528-5.
1 2 3 Andreasen NC (November 1979). "Thought, language, and communication disorders. I. Clinical assessment, definition of terms, and evaluation of their reliability". Archives of General Psychiatry. 36 (12): 1315–21. doi:10.1001/archpsyc.1979.01780120045006. PMID496551.
↑ Diagnostic and statistical manual of mental disorders: DSM-5 (5thed.). Arlington, VA: American Psychiatric Association. 2013. ISBN9780890425558.
1 2 3 Harvey PD, Keefe RS, Eesley CE (2017). "12.10 Neurocognition in Schizophrenia". In Sadock VA, Sadock BJ, Ruiz P (eds.). Kaplan & Sadock's Comprehensive Textbook of Psychiatry (10thed.). Wolters Kluwer. RELATIONSHIP OF NEUROCOGNITIVE IMPAIRMENT TO SCHIZOPHRENIA SYMPTOMS, Formal Thought Disorder. ISBN978-1-4511-0047-1.
"... In this way, alogia is conceived of as a 'negative thought disorder.' ..."
"... The paucity of meaningful content in the presence of a normal amount of speech that is sometimes included in alogia is actually a disorganization of thought and not a negative symptom and is properly included in the disorganization cluster of symptoms. ..."
1 2 3 4 5 Houghtalen, Rory P; McIntyre, John S (2017). "7.1 Psychiatric Interview, History, and Mental Status Examination of the Adult Patient". In Sadock, Virginia A; Sadock, Benjamin J; Ruiz, Pedro (eds.). Kaplan & Sadock's Comprehensive Textbook of Psychiatry (10th ed.). Wolters Kluwer. HISTORY AND EXAMINATION, Thought Process/Form, Table 7.1–6. Examples of Disordered Thought Process/Form. ISBN978-1-4511-0047-1. indicates and briefly defines the follow types: Clanging, Circumstantial, Derailment (loose associations), Flight of ideas, Incoherence (word salad), Neologism, Tangential, Thought blocking
↑ Videbeck S (2017). "8. Assessment". Psychiatric-Mental Health Nursing (7thed.). Wolters Kluwer. CONTENT OF THE ASSESSMENT, Thought Process and Content, p. 232. ISBN9781496355911.
↑ Videbeck (2017), Chapter 16 Schizophrenia, APPLICATION OF THE NURSING PROCESS, Thought Process and Content, p. 446.
1 2 3 4 5 6 7 Videbeck, S (2008). Psychiatric-Mental Health Nursing, 4th ed. Philadelphia: Wolters Kluwers Health, Lippincott Williams & Wilkins.
↑ APA dictionary of psychology (2015), p.299 "derailment n. a symptom of thought disorder, often occurring in individuals with schizophrenia, marked by frequent interruptions in thought and jumping from one idea to another unrelated or indirectly related idea. It is usually manifested in speech (speech derailment) but can also be observed in writing. Derailment is essentially equivalent to loosening of associations. See cognitive derailment; thought derailment."
"Form of Thought. Disorders of the form of thought are objectively observable in patients' spoken and written language. The disorders include looseness of associations, derailment, incoherence, tangentiality, circumstantiality, neologisms, echolalia, verbigeration, word salad, and mutism."
"Thought Process. ... Disorders of thought process include flight of ideas, thought blocking, impaired attention, poverty of thought content, poor abstraction abilities, perseveration, idiosyncratic associations (e.g., identical predicates and clang associations), overinclusion, and circumstantiality."
↑ Fred R. Volkmar; etal. (2005). Handbook of autism and pervasive developmental disorders. Vol.1: Diagnosis, development, neurobiology, and behavior (3rded.). Hoboken, NJ: John Wiley. ISBN978-0-470-93934-5. OCLC60394857.
↑ Duffy, Joseph R. (2013). Motor speech disorders: substrates, differential diagnosis, and management (Thirded.). St. Louis, MI. ISBN978-0-323-07200-7. OCLC819941855.{{cite book}}: CS1 maint: location missing publisher (link)
↑ Kaplan & Sadock's Comprehensive Textbook of Psychiatry (2017), Appendix B Glossary of Psychiatry and Psychology Terms. "evasion ... consists of suppressing an idea that is next in a thought series and replacing it with another idea closely related to it. Also called paralogia; perverted logic."
↑ Kaplan and Sadock's Concise Textbook of Clinical Psychiatry (2008), "Chapter 6 Psychiatric Rating Scales", OTHER SCALES, Table 6–6 Scale for the Assessment of Positive Symptoms (SAPS), Positive formal thought disorder, p. 45 includes and defines Derailment, Tangentiality, Incoherence, Illogicality, Circumstantiality, Pressure of speech, Distractible speech, Clanging.
↑ APA dictionary of psychology (2015), p.751overinclusion n. failure of an individual to eliminate ineffective or inappropriate responses associated with a particular stimulus.
1 2 3 4 5 6 Lewis SF, Escalona R, Keith SJ (2017). "12.2 Phenomenology of Schizophrenia". In Sadock VA, Sadock BJ, Ruiz P (eds.). Kaplan & Sadock's Comprehensive Textbook of Psychiatry (10thed.). Wolters Kluwer. THE SYMPTOMS OF SCHIZOPHRENIA, Disorganization, Thought Disorder. ISBN978-1-4511-0047-1.
As quoted in the templated quote.
"Thought disorder is the most studied form of the disorganization symptoms. It is referred to as "formal thought disorder," or "conceptual disorganization," or as the "disorganization factor" in various studies that examine cognition or subsyndromes in schizophrenia. ..."
1 2 Clinical Manifestations of Psychiatric Disorders (2017), THINKING DISTURBANCES, Continuity. "Word salad describes the stringing together of words that seem to have no logical association, and verbigeration describes the disappearance of understandable speech, replaced by strings of incoherent utterances."
↑ Kaplan & Sadock's Comprehensive Textbook of Psychiatry (2017), "Appendix B: Glossary of Psychiatry and Psychology Terms" "formal thought disorder Disturbance in the form of thought rather than the content of thought; thinking characterized by loosened associations, neologisms, and illogical constructs; thought process is disordered, and the person is defined as psychotic. Characteristic of schizophrenia."
↑ APA dictionary of psychology (2015), p.432 "formal thought disorder disruptions in the form or structure of thinking. Examples include derailment and tangentiality. It is distinct from TD, in which the disturbance relates to thought content."
As the proper FTD: "Schizophrenia Spectrum and Other Psychotic Disorders", Key Features That Define the Psychotic Disorders, Disorganized Thinking (Speech), p. 88 "Disorganized thinking (formal thought disorder) is typically inferred from the individual's speech. ..."
As possibly something else: "Dissociative Disorders", Differential Diagnosis, Psychotic disorders, p. 296 "... Dissociative experiences of identity fragmentation or possession, and of perceived loss of control over thoughts, feelings, impulses, and acts, may be confused with signs of formal thought disorder, such as thought insertion or withdrawal. ..."
F06.2 Organic delusional [schizophrenia-like] disorder, p.59: Features suggestive of schizophrenia, such as bizarre delusions, hallucinations, or thought disorder, may also be present. ... Diagnostic guidelines ... Hallucinations, thought disorder, or isolated catatonic phenomena may be present. ...
F20.0 Paranoid schizophrenia, p. 80: ... Thought disorder may be obvious in acute states, but if so it does not prevent the typical delusions or hallucinations from being described clearly. ...
F20.1 Hebephrenic schizophrenia, p. 81: ... In addition, disturbances of affect and volition, and thought disorder are usually prominent. Hallucinations and delusions may be present but are not usually prominent. ...
↑ The British Medical Association Illustrated Medical Dictionary. Dorling Kindersley. 2002. p.547. ISBN0-7513-3383-2. thought disorders Abnormalities in the structure or content of thought, as reflected in a person's speech, writing, or behaviour. ...
p. 470 psychosis: ... Symptoms include delusions, hallucinations, thought disorders, loss of affect, mania, and depression. ...
p. 499-500 schizophrenia: ... The main symptoms are various forms of delusions such as those of persecution (which are typical of paranoid schizophrenia); hallucinations, which are usually auditory (hearing voices), but which may also be visual or tactile; and thought disorder, leading to impaired concentration and thought processes. ...
↑ Matorin AA, Shah AA, Ruiz P (2017). "8 Clinical Manifestations of Psychiatric Disorders". In Sadock VA, Sadock BJ, Ruiz P (eds.). Kaplan & Sadock's Comprehensive Textbook of Psychiatry (10thed.). Wolters Kluwer. THINKING DISTURBANCES, Flow and Form Disturbances. ISBN978-1-4511-0047-1. Although formal thought disorder typically refers to marked abnormalities in the form and flow or connectivity of thought, some clinicians use the term broadly to include any psychotic cognitive sign or symptom.
Andreasen NC (November 1979). "Thought, language, and communication disorders. I. Clinical assessment, definition of terms, and evaluation of their reliability". Archives of General Psychiatry. 36 (12): 1315–21. doi:10.1001/archpsyc.1979.01780120045006. PMID496551.
Andreasen NC (November 1979). "Thought, language, and communication disorders. II. Diagnostic significance". Archives of General Psychiatry. 36 (12): 1325–30. doi:10.1001/archpsyc.1979.01780120055007. PMID496552.
Andreasen NC, Hoffrnann RE, Grove WM (1984). Alpert M (ed.). Mapping abnormalities in language and cognition. New York: Guilford Press. pp.199–226.{{cite book}}: |work= ignored (help)
1 2 Coryell W, Clayton PJ (2016). "4 Bipolar Illness". In Fatemi SH, Clayton PJ (eds.). The Medical Basis of Psychiatry (4thed.). New York: Springer Science+Business Media. 4.7. Clinical Picture, 4.7.2. Symptoms, p. 59. doi:10.1007/978-1-4939-2528-5. ISBN978-1-4939-2528-5.
↑ Oyebode F (2015). "10 Disorder of Speech and Language". Sims' Symptoms in the Mind: Textbook of Descriptive Psychopathology (5thed.). Saunders Elsevier. Schizophrenic Language Disorder, CLINICAL DESCRIPTION AND THOUGHT DISORDER, p. 167. ISBN978-0-7020-5556-0.
1 2 Thought Disorder (2016), 25.6. Relationship Between Thought Disorders and Other Symptoms of Schizophrenia., pp. 503–504.
↑ DSM-5 (2013), Schizophrenia Spectrum and Other Psychotic Disorders, Key Features That Define the Psychotic Disorders, Disorganized Thinking (Speech), p.88.
1 2 Ivleva EI, Tamminga CA (2017). "12.16 Psychosis as a Defining Dimension in Schizophrenia". In Sadock VA, Sadock BJ, Ruiz P (eds.). Kaplan & Sadock's Comprehensive Textbook of Psychiatry (10thed.). Wolters Kluwer. DSM-5: AN UPDATED DEFINITION OF PSYCHOSIS. ISBN978-1-4511-0047-1.
↑ Akiskal HS (2017). "13.4 Mood Disorders: Clinical Features". In Sadock VA, Sadock BJ, Ruiz P (eds.). Kaplan & Sadock's Comprehensive Textbook of Psychiatry (10thed.). Wolters Kluwer. BIPOLAR DISORDERS, Bipolar I Disorder, Acute Mania. ISBN978-1-4511-0047-1.
1 2 Ninivaggi FJ (2017). "28.1 Malingering". In Sadock VA, Sadock BJ, Ruiz P (eds.). Kaplan & Sadock's Comprehensive Textbook of Psychiatry (10thed.). Wolters Kluwer. CLINICAL PRESENTATIONS OF MALINGERING, Psychological Symptomatology: Clinical Presentations, Psychosis. ISBN978-1-4511-0047-1.
↑ Sikich L, Chandrasekhar T (2017). "53 Early-Onset Psychotic Disorders". In Sadock VA, Sadock BJ, Ruiz P (eds.). Kaplan & Sadock's Comprehensive Textbook of Psychiatry (10thed.). Wolters Kluwer. DIFFERENTIAL DIAGNOSIS, Autism Spectrum Disorders. ISBN978-1-4511-0047-1.
1 2 Thought Disorder (2016), 25.6. Relationship Between Thought Disorders and Other Symptoms of Schizophrenia., pp. 503–504.cited
Arndt S, Alliger RJ, Andreasen NC (March 1991). "The distinction of positive and negative symptoms. The failure of a two-dimensional model". The British Journal of Psychiatry. 158: 317–22. doi:10.1192/bjp.158.3.317. PMID2036528. S2CID41383575.
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↑ Miller DD, Arndt S, Andreasen NC (2004). "Alogia, attentional impairment, and inappropriate affect: their status in the dimensions of schizophrenia". Comprehensive Psychiatry. 34 (4): 221–6. doi:10.1016/0010-440X(93)90002-L. PMID8348799.
↑ Phenomenology of Schizophrenia (2017), THE SYMPTOMS OF SCHIZOPHRENIA, Negative Symptoms. "The two-syndrome concept as formulated by T. J. Crow was especially important in spurring research into the nature of negative symptoms... but this does not diminish the creative efforts that led to these scales or importance of these scales for research. In fact, it was only through careful analysis of the structure of symptoms in these scales that a more accurate characterization of the phenomenology of schizophrenia was possible."
Sadock VA, Sadock BJ, Ruiz P, eds. (2017). Kaplan & Sadock's Comprehensive Textbook of Psychiatry (10thed.). Wolters Kluwer. ISBN978-1-4511-0047-1.
Sadock BJ, Sadock VA (2008). Kaplan and Sadock's Concise Textbook of Clinical Psychiatry. Lippincott Williams & Wilkins. ISBN9780781787468.
Andreasen NC (2016). "25 Thought Disorder". In Fatemi SH, Clayton PJ (eds.). The Medical Basis of Psychiatry (4thed.). New York: Springer Science+Business Media. pp.497–505. doi:10.1007/978-1-4939-2528-5. ISBN978-1-4939-2528-5.
McKenna PJ, Oh TM (2005). Schizophrenic Speech: Making Sense of Bathroots and Ponds that Fall in Doorways. Cambridge University Press. ISBN978-0-521-81075-3.
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