Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036341 (schizophrenia)
 60,220 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

During a 13-month period, 9 patients with phencyclidine-induced psychosis were admitted to Darnall Army Hospital. They exhibited hostility agitation, and tangentiality and had delusions of influence and religious grandiosity. Six subjects reported auditory hallucinations, and 4 were disoriented in at least 1 sphere. Despite treatment with antipsychotic medication, the psychotic episodes often persisted for more than 30 days. Our clinical finding of prolonged psychotic reactions, together with previous reports of the effects of phencyclidine, suggests that phenycyclidine provides an intriguing drug model for schizophrenia.
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PMID:Phencyclidine-induced psychosis. 69 30

The authors compared nine manic patients exhibiting formal thought disorders (tangentiality, neologisms, drivelling, private use of words, and paraphasias) with 102 manic patients without these thought disorders and with 31 schizophrenic patients. Manic patients with formal thought disorders tended to have more "schizophrenic" symptoms than did manic patients without formal thought disorders, but both groups improved significantly more during the index episode than did the schizophrenic patients. Although the prevalence of flight of ideas was high in mania, narrowly defined formal thought disorder was rare, suggesting that precise definition and description of thought disorders would be helpful in distinguishing mania from schizophrenia.
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PMID:The diagnostic implications of formal thought disorder in mania and schizophrenia: a reassessment. 292 45

The aim of this study was to examine whether specific forms of formal thought disorder distinguish schizophrenia from schizophreniform and schizoaffective psychoses. The sample was composed of 82 consecutively admitted patients with schizophrenic symptoms. Of these, 28 had a diagnosis of schizophrenia by RDC and DSM-IIIR criteria, 28 a diagnosis of schizophrenia by RDC but not DSM-IIIR (consequently they were labeled schizophreniform), and 26 a diagnosis of manic schizoaffective disorder by RDC criteria. They were assessed by a semi-structured interview for schizophrenia, by scales for positive and negative symptoms (SAPS and SANS) and by prognostic indicators. The assessment of thought disorder was carried out by using the Thought, Language and Communication scale (TLC). The schizophrenic patients showed higher global scores on formal thought disorder, and some of its subtypes were 'most specific' to schizophrenia (poverty of speech, poverty of content of speech, illogicality, tangentiality and perseveration). Schizophrenics had more loose associations than schizophreniforms. Manic schizoaffectives had higher scores on positive versus negative formal thought disorder than schizophreniforms. We suggested that the assessment of disordered thinking by the TLC may facilitate the differential diagnosis of psychotic disorders during the acute phase of the illness.
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PMID:Does formal thought disorder differ among patients with schizophrenic, schizophreniform and manic schizoaffective disorders? 839 47

Kraepelin said severe mental illness was due to 2 diseases subsequently characterized as disorders of thought vs disorders of mood, ie, the Kraepelinian dichotomy. Schizophrenia, traditionally considered the disorder of thought, has been defined by the presence of hallucinations, delusions, catatonia, and disorganization. Tangentiality, derailment, loose associations, and thought blocking are typically considered pathognomonic of schizophrenia. By contrast, the mood disorders have been characterized only as disorders of the emotions, though both depression and mania, when severe, are now recognized to include the same psychotic features traditionally considered diagnostic of schizophrenia. This article addresses disordered thinking in mania in order to clarify the relationship between schizophrenia and psychotic mood disorders. Normally, the brain's selective attention mechanism filters and prioritizes incoming stimuli by excluding from consciousness extraneous, low-priority stimuli and grading the importance of more relevant data. Because this "filter/prioritizer" becomes defective in mania, tangential stimuli are processed without appropriate prioritization. Observed as distractibility, this symptom is an index of the breakdown in selective attention and the severity of mania, accounting for the signs and symptoms of psychotic thinking. The zone of rarity between schizophrenia and psychotic mood disorders is blurred because severe disorders of mood are also disorders of thought. This relationship calls into question the tenet that schizophrenia is a disease separate from psychotic mood disorders. Patients whose case histories are discussed herein gave their written informed consent to participate in this institutional human subjects committee-approved protocol.
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PMID:Disorders of thought are severe mood disorders: the selective attention defect in mania challenges the Kraepelinian dichotomy a review. 1751 40

Abnormal language in schizophrenia has been regarded as a hallmark of this disorder. Language abnormalities include loose and unusual associations, tangentiality, and inability to maintain a topic. Recent theories of language dysfunction have invoked working memory abnormalities, as well as abnormal processes within semantic memory in schizophrenia. Two views, often construed as opposing, have been offered to account for language peculiarities in schizophrenia: one holds that initial processes of activation are abnormal while the other holds that late processes of context utilization might be disturbed. We suggest that these views may be complementary rather than mutually exclusive. Given the relative paucity of data on the early processes within semantic networks, we present new evidence using ERP short SOA paradigm that these processes are abnormal in schizophrenia. Furthermore, reduced N400 in the unrelated condition found in this study suggests that the abnormality was related to inefficient early inhibitory processes.
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PMID:Abnormal inhibitory processes in semantic networks in schizophrenia. 1984 Aug 22

This study examines in detail - i) the magnitude, nature and severity of thought disorder in schizophrenia, ii) the correlations between type and severity of thought disorder with socio-demographic and clinical variables, and iii) differences between different subtypes of schizophrenia. Forty five schizophrenics (Research Diagnostic Criteria) were assessed by 'live' interview as well as tape recorded interviews. Instruments used for assessment were (a) Scale for assessment of Thought, Language and Communication (Andreasen 1978), (b) Brief Psychiatric Rating Scale (Overall & Gorham 1962), (c) Mini Mental State (Folstein 1975), and (d) Clinical and demographic data recording proforma. The Schizophrenic patients were subdivided as (i) Acute and chronic (R.D.C.), (ii) Paranoid and non-paranoid; and (iii) Negative, positive, mixed (Andreasen's criteria) and intragroup and intergroup differences were computed.Poverty of speech, tangentiality, derailment, loss of goal, perseveration were found to be the commonest thought disorders. Positive and negative thought disorders were seen in equiproportion in both positive and negative schizophrenics. Significant differences were noted between thought disorders and education as well as habitat. Rural patients more often had negative formal thought disorders. Literates had more often clanging, neologism, circumstantiality and echolalia. This study provides ample information on the nature of thought disorder in Indian schizophrenic subjects.
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PMID:A study of thought, language and communication (T.L.C) disorders in schizophrnia. 2192 21

Language and speech are the primary source of data for psychiatrists to diagnose and treat mental disorders. In psychosis, the very structure of language can be disturbed, including semantic coherence (e.g., derailment and tangentiality) and syntactic complexity (e.g., concreteness). Subtle disturbances in language are evident in schizophrenia even prior to first psychosis onset, during prodromal stages. Using computer-based natural language processing analyses, we previously showed that, among English-speaking clinical (e.g., ultra) high-risk youths, baseline reduction in semantic coherence (the flow of meaning in speech) and in syntactic complexity could predict subsequent psychosis onset with high accuracy. Herein, we aimed to cross-validate these automated linguistic analytic methods in a second larger risk cohort, also English-speaking, and to discriminate speech in psychosis from normal speech. We identified an automated machine-learning speech classifier - comprising decreased semantic coherence, greater variance in that coherence, and reduced usage of possessive pronouns - that had an 83% accuracy in predicting psychosis onset (intra-protocol), a cross-validated accuracy of 79% of psychosis onset prediction in the original risk cohort (cross-protocol), and a 72% accuracy in discriminating the speech of recent-onset psychosis patients from that of healthy individuals. The classifier was highly correlated with previously identified manual linguistic predictors. Our findings support the utility and validity of automated natural language processing methods to characterize disturbances in semantics and syntax across stages of psychotic disorder. The next steps will be to apply these methods in larger risk cohorts to further test reproducibility, also in languages other than English, and identify sources of variability. This technology has the potential to improve prediction of psychosis outcome among at-risk youths and identify linguistic targets for remediation and preventive intervention. More broadly, automated linguistic analysis can be a powerful tool for diagnosis and treatment across neuropsychiatry.
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PMID:Prediction of psychosis across protocols and risk cohorts using automated language analysis. 2935 48

Although rating scales to assess formal thought disorder exist, there are no objective, high-reliability instruments that can quantify and track it. This proof-of-concept study shows that CoVec, a new automated tool, is able to differentiate between controls and patients with schizophrenia with derailment and tangentiality. According to ratings from the derailment and tangentiality items of the Scale for the Assessment of Positive Symptoms, we divided the sample into three groups: controls, patients without formal thought disorder, and patients with derailment/tangentiality. Their lists of animals produced during a one-minute semantic fluency task were processed using CoVec, a newly developed software that measures the semantic similarity of words based on vector semantic analysis. CoVec outputs were Mean Similarity, Coherence, Coherence-5, and Coherence-10. Patients with schizophrenia produced fewer words than controls. Patients with derailment had a significantly lower mean number of words and lower Coherence-5 than controls and patients without derailment. Patients with tangentiality had significantly lower Coherence-5 and Coherence-10 than controls and patients without tangentiality. Despite the small samples of patients with clinically apparent thought disorder, CoVec was able to detect subtle differences between controls and patients with either or both of the two forms of disorganization.
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PMID:Computational linguistic analysis applied to a semantic fluency task to measure derailment and tangentiality in schizophrenia. 2950 41