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

Fourteen published scales of psychotic traits or symptoms (measuring various delusional states, magical ideation, perceptual aberration, disposition towards hallucination, hypomanic personality, schizotypal personality, borderline personality and anhedonia) were combined with the Eysenck Personality Questionnaire to form a Combined Schizotypal Traits Questionnaire (CSTQ) which was administered to 180 normal subjects. Two factor analyses were carried out on the scale scores. The first analysis excluded symptom scores derived from the Delusions Symptoms States Inventory of Foulds and Bedford and yielded a three-factor solution which appeared to measure traits relating to (i) positive psychotic symptomatology; (ii) negative psychotic symptomatology; and (iii) aspects of schizotypy involving social anxiety and cognitive disorganization. The Foulds scales were included in the second analysis which yielded a four-factor solution. The first three factors were similar to those obtained from the first analysis; the fourth factor seemed to measure an asocial component of schizotypy. This last factor was mainly accounted for by the P scale from the EPQ. These results support previous findings suggesting that different schizotypy scales relate to different underlying aspects of schizophrenia. The findings also indicate that psychotic traits are distributed along at least three dimensions.
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PMID:The multidimensional nature of schizotypal traits: a factor analytic study with normal subjects. 260 89

Anhedonia, the loss of the capacity of feeling pleasure, was first introduced at the end of the last century by a French psychologist, Ribot, and has been the object of much research, essentially in English, for the last decades, in schizophrenia, in depression, in schizoid disorders. After considering the problems of quantitative evaluation, we review the literature and conclude that anhedonia appears to be a multi-morphological symptom and the are probably several types of anhedonia, which shows the necessity of developing more specific reliable evaluation instruments and of diversifying the approaches. We show the utility, in particular, of a psychophysiological approach using endogenous Evoked Potentials. Then several research directions in psychiatry are discussed: what place has anhedonia in the negative form of schizophrenia? Does anhedonia constitute a specific marker of certain endogenous depressions? Does it constitute a personality trait that predisposes to morbidity?
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PMID:[Anhedonia in psychiatry: a review]. 269 84

This study tested the hypothesis that psychosis-prone individuals show patterns of visual search that suggest a lateralized cerebral hemispheric abnormality, similar to one hypothesized by Venables (1980) to underlie cognitive dysfunction in schizophrenia. Self-report measures of psychiatric vulnerability were completed by 881 college students. Experimental subjects (n = 73) were those with high scores on one of four psychosis-proneness scales. Control subjects (n = 33) scored within 0.5 SD of the mean on all scales. Subjects were tested using verbal and nonverbal visual search tasks designed to detect abnormalities in the spatial distribution of attention. When searching random arrays of nonverbal stimuli, 53% of the experimental subjects used an erratic search strategy similar to that typically observed in right-brain-damaged patients, compared with 23% of controls. The most deviant search patterns were shown by subjects who scored high on Physical Anhedonia and Perceptual Aberration-Magical Ideation. The results suggest that early development of schizophrenic disorder might be associated with dysfunction of right-hemispheric mechanisms of attentional control.
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PMID:Spatial attention in hypothetically psychosis-prone college students. 271 Aug 66

In searching for reliable animal models of negative schizophrenic symptomatology, we considered the possibility that a deficient response to rewarding stimuli might be the basis for some features of the disease. Apomorphine (0.015 and 0.03 mg/kg) and 3-PPP (1 mg/kg) caused such a reward deficit when rats were shifted from continuous reinforcement to a fixed ratio (FR4) schedule of food delivery. Further experiments indicated that this effect could be accounted for by a decreased ability of secondary reinforcers to sustain responses, rather than by motor impairment, appetite loss, or reduced reward value of the food. If this deficit is due to decreased dopaminergic transmission produced by low doses of dopamine agonists, our model might suggest that some symptoms of schizophrenia (anhedonia for instance) are not incompatible with deficient dopaminergic transmission. Low to moderate doses of sulpiride, amisulpride, pimozide, and pipotiazine, but not fluphenazine, metoclopramide, haloperidol, thioridazine, and chlorpromazine, reversed the apomorphine-induced reward deficit. Although any extrapolation from animal data requires caution, it may be tentatively proposed that only some neuroleptics, at dosages insufficient to block dopamine transmission postsynaptically, can be effective in reducing negative schizophrenic symptoms.
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PMID:Performance deficit induced by low doses of dopamine agonists in rats. Toward a model for approaching the neurobiology of negative schizophrenic symptomatology? 286 89

Scales for the measurement of social and physical anhedonia, the lowered ability to experience pleasure, were investigated. Both scales were devised by Chapman et al. German versions of these two patient populations and two groups of normal subjects. The reliability and scale intercorrelation coefficients were acceptable for the scales overall, but not for the separate subscales. Patients scored higher on both scales than normal subjects, and patients with neurotic depression had higher scores than those with a diagnosis of schizophrenia. A significant correlation with a chronic course was identified in the schizophrenic patients. Item analysis and factor analysis did not reveal any significant common dimensions in the 87 items in the original scales. Only 17 items in the physical anhedonia scale and 26 items in the social anhedonia scale met test-theoretical criteria of acceptability for inclusion in a German version of these scales. Discrepancies and congruencies between American and German studies were discussed, as were further criteria that might make it possible to improve research instruments of this kind.
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PMID:[Psychological and social anhedonia. Evaluation of a research instrument for measuring a basic psychopathologic disorder]. 358 31

The Chapman physical anhedonia (AN) and perceptual aberration (AB) scales were intended to identify high risk for schizophrenia. Although schizophrenic-like dysfunctions have been reported in association with each, the issue is clouded by possible relationships with depression. We recently reported psychophysiological patterns distinguishing depression from schizophrenia. Schizophrenics showed reduced orienting response (OR) to innocuous stimuli in both electrodermal (SCR) and finger pulse (FPV) components, normalizing in both to significant signals. Depressives showed deficient, non-normalizing SCR, but normal FPV, implicating SCR/cholinergic rather than OR deficits. 16 AN, 18 AB, and 17 control students received an innocuous (habituation) tone series followed by a significant (alternating-press) series. ANs displayed schizophrenic-like rather than depressive-like response patterns, but ABs showed no coherent pattern. Findings in ANs were somewhat attenuated compared with schizophrenics, perhaps reflecting the small percentage of schizophrenics-to-be in this risk group. The absence of clear deficit in ABs agrees with studies showing OR deficits to be associated with more negative symptoms in schizophrenia.
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PMID:Psychophysiological response patterns in college students with high physical anhedonia: scores appear to reflect schizotypy rather than depression. 360 12

The performance on spatial and nonspatial associative learning tasks was tested in a sample of male drug-free DSM III-diagnosed schizophrenic patients and in a closely matched normal control group. Schizophrenics showed a worse performance on both versions of the task, but especially on the nonspatial one. A significant correlation was observed between some indices of the nonspatial task and the scores on two subscales (affective flattening and anhedonia) of the scale for the assessment of negative symptoms by Andreasen. These results are consistent with the hypothesis of a dysfunction of dorsolateral prefrontal cortex in schizophrenia and with the postulated linkage between such dysfunction and negative schizophrenic symptomatology.
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PMID:Conditional associative learning in drug-free schizophrenic patients. 362 90

Symptom frequency and severity were compared in two sequential clinically referred samples of 95 children and 92 adolescents, aged 6 to 18 years, all medically healthy, assessed with the Schedule for Affective Disorders and Schizophrenia for School Age Children, Present Episode, who met unmodified Research Diagnostic Criteria for major depressive disorder (MDD). There were no significant differences between the two groups in the majority of depressive symptoms. However, prepubertal children had greater depressed appearance, somatic complaints, psychomotor agitation, separation anxiety, phobias, and hallucinations, whereas adolescents had greater anhedonia, hopelessness, hypersomnia, weight change, use of alcohol and illicit drugs, and lethality of suicide attempt, but not severity of suicidal ideation or intent. Adolescents with a duration of the depressive episode of two years or greater had significantly higher rates of suicidal ideation and intent, lethality, and number of suicide attempts than youngsters with depressive episodes of shorter duration. A principal components factor analysis of psychiatric symptoms was carried out in all 296 youngsters evaluated during the same period who met DSM-III criteria for any Axis I diagnosis. The majority had an affective disorder. Factors were quite similar for both adolescents and children and included an "endogenous" and an "anxious" factor, as in many studies of adult depression. In addition, three other factors were found: negative cognitions, appetite and weight changes, and a conduct factor. Suicidal ideation was a component of both the negative cognitions factor and the conduct factor.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The clinical picture of major depression in children and adolescents. 366 42

This project was designed to test two hypotheses drawn from a new formulation explaining the exaggerated winter birthrate among hospitalized schizophrenics. The first is that the supposed exaggerated winter birthrate among process schizophrenics actually represents a reduction in spring-fall births caused by prenatal exposure to infectious diseases during the preceding winter--i.e., a high prenatal death rate in process preschizophrenic fetuses. The second is that the level of negative symptoms in survivors at risk for schizophrenia who were born after winters with high infectious disease rates is exaggerated. The findings provided some tentative support for this formulation. Compared with counterparts born after low-disease winters, schizophrenics born after winters with high disease incidences tended to show lower (more reactive) scores on a measure of the process-reaction dimension but higher anhedonia scores.
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PMID:The relationships of anhedonia and the process-reactive dimension to season of birth and infectious disease incidence in schizophrenia. 380 69

Two studies were conducted to evaluate the ability of schizotypic subjects to track the horizontal movement of a light source across the face of an oscilloscope. In the first experiment, subjects were selected based on their scores on the Physical Anhedonia Scale (Chapman et al., 1976). The high anhedonic group was found to be significantly more variable than the low anhedonic group and contained three subjects with particularly deviant smooth pursuit eye movements (SPEM). In the second study, an additional group of schizotypic subjects who scored high on the Perceptual Aberration Scale (Chapman et al., 1978) was selected. In this study, eye-tracking records produced by both the anhedonic and perceptual aberration subjects were more variable than those recorded from control subjects, and once again, the most deviant records were produced by a small subgroup (n = 10) of the schizotypic subjects. These questionnaire-identified schizotypes with poor tracking ability might comprise a group of subjects especially vulnerable to a future schizophrenia-like disorder.
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PMID:Smooth pursuit eye movements in subjects reporting physical anhedonia and perceptual aberrations. 386 Aug 82


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