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Query: UMLS:C0036341 (schizophrenia)
 60,220 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The relationships between negative symptomatology and anhedonia have been studied on 61 subjects who had Research Diagnostic Criteria for chronic schizophrenia. Negative symptomatology was rated by the negative subscales of the Kay Positive and Negative Syndrome Scale (PANSS) and of the Brief Psychiatric Rating Scale (BPRS). Anhedonia was rated by the Physical Anhedonia Scale of Chapman (PAS), the Fawcett-Clark Pleasure Capacity Scale-Physical Pleasure (FCPCS-PP), and the social interest subscale (SIS) of the Nurse Observation Scale for Inpatients (NOSIE-30). Pearson correlations were calculated between negative and anhedonia scales. Schizophrenics were dichotomized first into negatives and positives using the composite score of the PANSS, and second into low and high negatives using the negative subscale of the PANSS. For each dichotomy, the corresponding subgroups were compared on anhedonia scales using Student's test. The results have shown no significant correlations between negative and anhedonia scales (PAS and FCPCS-PP). There were no significant differences concerning the PAS and the FCPCS-PP between negative and positive subgroups of schizophrenics and between low- and high-negative subgroups. Anhedonia is not a negative symptom. Our results confirm the reported studies on subjective experiences in schizophrenia. A search for more restricted forms of schizophrenia characterized by severe anhedonia is needed.
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PMID:Anhedonia and negative symptomatology in chronic schizophrenia. 877 May 19

Schizophrenia is an illness with numerous neurobiologic features. It is hypothesized that patients may have a relative deficit of dopamine neurotransmission in the nigrostriatal and mesocortical tracts of the brain, as contrasted with an excess of dopamine neurotransmission in the mesolimbic area. The dopamine deficit may be related to the negative symptoms (blunted affect, anhedonia, asociality, inability to initiate and carry out complex tasks to completion) of schizophrenia, whereas the dopamine excess may be responsible for the positive symptoms (hallucinations, delusions, and thought disorder). Compared with healthy subjects, schizophrenic patients may also have increased levels of serotonin and decreased levels of norepinephrine in the brain. Conventional antipsychotic drugs nonselectively block dopamine D2 receptors throughout the central nervous system. This may help reduce positive symptoms, but has little or no effect on negative symptoms. Newer agents have more anatomically selective activity with respect to dopaminergic systems but are more complex with respect to their actions in other neurochemical systems, such as serotonin and norepinephrine, which presumably contributes to their apparent greater therapeutic efficacy.
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PMID:Pathophysiology of schizophrenia and the role of newer antipsychotics. 877 81

103 patients were for the first time admitted to the psychiatric hospital (Institute of Psychiatry and Neurology in Warsaw) between 1976-1983 and received a research diagnosis of schizophrenia (in accordance with the ICD-9 criteria). The course and clinical pattern of the illness were analyzed at a follow-up in 65 patients--re-hospitalized in the 5th year from their first admission. As regards the clinical pattern analysis, it was focused mostly on negative symptoms occurrence, as assessed using the Andreasen Scales (SANS). The data obtained from the case reports were statistically tested and the results were presented in the tables according to the research questions. The stability of the negative symptoms in the early stage of the schizophrenia psychosis was examined. The author confirms that presence of negative symptoms (alogia, apathy and anhedonia) at first hospitalization has been associated with the symptoms recurrence during rehospitalization at the five-year follow-up.
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PMID:[Persistence of negative symptoms in the early phase of schizophrenic psychosis]. 884 5

While structured psychiatric interviews have generally succeeded in identifying higher rates of schizotypal personality disorder in relatives of schizophrenia versus control probands, self-report questionnaires designed to assess schizotypy have been less successful at distinguishing these groups of relatives. In the Roscommon Family Study, an epidemiologically based, case-controlled study conducted in the west of Ireland, relatives were administered a short form of Eysenck's Psychoticism scale and shortened and modified versions of the scales for magical ideation and social anhedonia developed by Chapman and colleagues. We compared, with relatives of matched controls, relatives of four proband groups: schizophrenia, other nonaffective psychoses (ONAP), psychotic affective illness (PAI), and nonpsychotic affective illness (NPAI). Only social anhedonia scores successfully differentiated, at modest levels of significance, relatives of schizophrenia versus control probands. Levels of magical ideation did not distinguish relatives of schizophrenia, ONAP, PAI, or NPAI probands from relatives of controls. Compared to controls, ONAP probands had significantly elevated psychoticism scores, but no such increase was seen in relatives of schizophrenia, PAI, or NPAI probands. Dimensions of schizotypy assessed at personal interview were significantly better at differentiating relatives of schizophrenia and control probands than our measures of social anhedonia, magical ideation, or psychoticism. Although psychiatric interviews in this sample have shown that clinically assessed schizotypal personality disorder and traits strongly aggregate in relatives of schizophrenia patients, of the three self-report instruments designed to assess schizotypy, only one even modestly identifies relatives of schizophrenia versus control probands. These results suggest that, compared with psychiatric interviews, self-report questionnaires are less successful at assessing underlying familial vulnerability to schizophrenia.
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PMID:Self-report measures of schizotypy as indices of familial vulnerability to schizophrenia. 887 1

Development regressive events such as pruning of synapses are implicated in schizophrenia with both over- and under-connectivity models proposed (Randall, Feinberg, Hoffman). Saugstad theorized that extremes of normal variation in age at puberty distinguish affective psychoses (early maturation) from schizophrenia (late maturation). In normal students we have found a three-factor structure of schizotypy traits (Active, Withdrawn and Unreality) which may parallel three-syndrome models of schizophrenia. Here, in a sample of 161 students we examined relations between schizotypy and extremes in the timing of puberty. Relations were almost exclusively syndromal. Unreality was associated with both extremes when compared with a group of normal maturers. Comparing early with late maturers, early maturing females were found to be Withdrawn, with features of social withdrawal and anhedonia. In contrast, Withdrawn males were late maturers, with features of social withdrawal and social anxiety. In females it was the Active syndrome (odd speech, impulsivity and activity) that was associated with late maturation. The results have relevance for both neurophysiological and social theories of personality, sex differences and psychopathology.
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PMID:Syndromes of schizotypy and timing of puberty. 888 46

Individuals with schizotypal personality disorder (SPD) are thought to be phenotypically related to individuals with schizophrenia. This assumption is partially supported by the fact that SPD patients have deficits on biological markers similar to those found in schizophrenia. Visual backward masking (VBM) performance and critical stimulus duration (CSD), measures of information processing found to be abnormal in schizophrenia patients, were assessed in 14 SPD and 21 comparison subjects. There was no significant difference between groups in VBM performance; however; there were significant correlations between VBM deficits and the number of SPD symptoms, as well as elevated scores on the Ego. Impairment Index (EII). Additionally, there was a trend (p = 056) toward elevations in CSD in the SPD versus the comparison group and CSD inflation appears to be most prominent in individuals with a greater number of social deficit symptoms and elevated physical anhedonia scores. These findings suggest an important relationship between symptoms of SPD and neurophysiologic deficits.
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PMID:The relationship of information-processing deficits and clinical symptoms in schizotypal personality disorder. 889 71

The study of individuals at the boundaries of schizophrenia has historically involved genetic relatives of schizophrenia patients or individuals who meet criteria for schizotypal personality disorder (SPD). Recently, many investigators have turned to the use of psychometric scales, developed to measure psychotic traits or vulnerability to developing schizophrenia, to screen large populations of college students in order to identify individuals who are "psychosis prone" or "schizotypal". To help answer the question of whether students identified with psychometric scales are indeed psychosis prone, we screened 1115 college students with the Perceptual Aberration/ Magical Ideation (PerMag) and Physical Anhedonia (PhysAn) Scales. Individuals who scored 2 standard deviations (SD) above the mean on the scales were selected as experimental subjects (N = 13 PerMag, N = 10 PhysAn) and a subpopulation of matched subjects who scored less than 0.5 SD above the mean were selected as control subjects (N = 24). All subjects then received a full battery of tests, including structured clinical interviews, the MMPI, and psychophysiological measures of information processing, including prepulse inhibition and habituation of the human startle response, visual backward masking and reaction time measures. The results suggest that the PerMag scale, but not the PhysAn scale, identifies individuals with some psychotic, affective and anxiety symptoms when compared to the controls. Neither scale predicts a diagnosis of schizotypal personality disorder or deficits on measures of information processing that characterize schizophrenia or schizotypal personality disordered patients.
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PMID:Clinical and experimental characteristics of "hypothetically psychosis prone" college students. 892 37

A replication is reported of a three-factor--active, withdrawn, unreality--structure of schizotypy measured with the Schizotypal Personality Questionnaire (SPQ) in the normal population, a structure which has close affinities with a three-syndrome model of schizophrenia. Cognitive asymmetry patterns and arousal scales are found in the companion report--Part II in this issue of the Schizophrenia Bulletin. Here the withdrawn factor--loneliness and constricted affect--was also complemented by the physical anhedonia scale. The original sample (1995) was then combined with the replication sample to examine associations with the dimensions of extraversion-introversion, neuroticism, and psychoticism. Introversion loaded on the first withdrawn factor. The second unreality factor--unusual perceptions, magical beliefs, and ideas of reference--was unrelated to the Eysenck dimensions. Psychoticism loaded on the third active factor--eccentricity and odd speech. Neuroticism formed a fourth, nonspecific factor with social anxiety and suspiciousness. Insufficiencies in current measures of the structure of schizotypy and schizophrenia are discussed. These include the absence of activity-arousal from the SPQ, the limited assessment of cognitive disorganization in schizotypy, and its heterogeneity in schizophrenia. The history of the active-withdrawn classification and its importance in further elucidation of schizotypy and schizophrenia are outlined.
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PMID:The factorial structure of schizotypy: Part I. Affinities with syndromes of schizophrenia. 893 15

Having finalized the ICD 10, the WHO is now preparing a new version of the "International Classification of Impairments, Disabilities and Handicaps" (ICIDH). At present this threefold scheme is designed to classify the consequences of mental illness. Impairment is defined as either a loss of function or a damage to structure. Disability is the resulting limitation in performance. The restriction in the ability to fulfill social roles is known as role handicap. These three aspects conceptualised in strict sequence have thus far been understood only in terms of the result of the illness. The planned review of the ICIDH will most likely consist of substituting this rather rigid scheme by a more flexible one. This will allow for feedback mechanism between the different levels. Premorbid disabilities/handicaps as possible risk factors for the development of mental illness may even be taken into consideration. The analyses within the Mannheim ABC schizophrenia study have convincingly shown that social disability and role handicaps are present in a high percentage of patients (57%) prior to the onset of the first psychotic symptom. On an average they begin about two to four years before the first hospitalisation and one to three years prior to the first psychotic symptom. While the correlation between social disability and positive symptoms is not significant, disability and negative symptoms are closely related. In addition to this only part of this correlation can be explained as a conceptual overlap (i.e. the SANS subscales Avolition and Anhedonia have items comparable to the Disability Assessment Schedule). In fact, we found comparably high correlations between affective blunting and alogia and social disability as well. Patients with early disability not only have an overall unfavourable course of negative symptoms but negative symptoms are shown to be useful predictors for social disability three years after the first hospitalisation.
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PMID:[Psychiatric handicap--precursor or social sequelae of schizophrenia?]. 896 96

The differential allocation of attentional resources to attended and ignored stimuli was examined by measuring skin conductance orienting responses and secondary reaction time in relatively asymptomatic schizophrenia outpatients, demographically matched normal controls, college students putatively at risk for psychosis, and a college student control group. At-risk participants were those with extreme scores on scales for either anhedonia or perceptual aberration-magical ideation (per-mags). Compared to control groups, the patients and per-mags showed secondary reaction time results suggesting a delay in the differential allocation of attentional resources. This deficit was observed particularly in patients and matched controls with few or no skin conductance orienting responses, suggesting that impaired autonomic orienting is related to underlying cognitive-attentional vulnerability factors.
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PMID:Autonomic orienting and the allocation of processing resources in schizophrenia patients and putatively at-risk individuals. 913 37


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