Negative metabolic effects of cyclic GMP in quiescent cardiomyocytes are not related to L-type calcium channel activity

Evidence of immune system abnormalities in adult schizophrenia has prompted examination of the human leukocyte antigen (HLA) system. Childhood onset schizophrenia offers a unique opportunity to test neurodevelopmental hypotheses of schizophrenia, including those which implicate components of the immune system. In the present study, class I and II HLA antigens were typed using sequence-specific primers and the polymerase chain reaction in 28 childhood onset schizophrenics and 51 ethnically matched healthy subjects. Groups were compared for frequencies of HLA antigens reported to be associated with schizophrenia and/or autoimmune disorders. We hypothesized that antigen frequencies would differ between schizophrenic and healthy children, suggesting that some dimension of the neurodevelopmental disturbance experienced by these children may be mediated by subtle abnormalities of immune function. There were no significant differences between schizophrenic and healthy subjects in the frequency of any antigen tested. These findings do not support HLA-associated pathology in childhood onset schizophrenia.     

Relation between current diagnostic criteria for schizophrenia and the dimensions of premorbid adjustment, paranoid symptomatology, and chronicity.

46 broadly defined schizophrenics were diagnosed according to 7 current diagnostic criteria for schizophrenia, and the subtyping dimensions of premorbid adjustment, paranoid symptomatology, and chronicity were assessed. Despite the minimal overlap between many of these criteria, samples selected by each of these systems were comparable in terms of the 3 subtyping dimensions. Results indicate that patients diagnosed as schizophrenic by each of these criteria were similar to schizophrenics who failed to meet those particular criteria with respect to premorbid adjustment, paranoid symptomatology, and chronicity. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impairment in abstract responses of schizophrenics, neurotics, and brain-damaged patients

Attempted to identify a deficit in information input that may be specific to schizophrenia. The Ss were 60 male 19–58 yr old veterans representing 5 groups of 12 each: normals, neurotics, paranoid schizophrenics, nonparanoid schizophrenics, and brain-damaged patients. In the present and previous studies scores on single- and multiple-proverbs tests were analyzed to show effects of stimulus enrichment and practice gain in identifying this deficit. Previous studies differentiate normals and schizophrenics, demonstrate the deficit over a range of schizophrenic severity, and show that the deficit is independent of general loss of competence. Results of the present study indicate that the deficit is present over the paranoid–nonparanoid continuum; that it is absent in normals, neurotics, and brain-damaged patients; and that it is not a function of such intellectual factors as education and vocabulary. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Premorbid competence, role orientation, and gender differences in DSM-II versus DSM-III schizophrenic patients.

The study compared 71 patients diagnosed as schizophrenic or within the schizophrenia spectrum according to Diagnostic and Statistical Manual of Mental Disorders (DSM-II) with 66 patients who received similar diagnoses according to DSM-III. On measures of premorbid competence and role orientation, DSM-II and DSM-III schizophrenic patients obtained comparable scores. The DSM-III patients with schizophrenic versus schizophrenia spectrum diagnoses also obtained comparable scores on these measures. The gender differences in premorbid competence and role orientation that have consistently characterized DSM-II schizophrenics continued to characterize DSM-III schizophrenic and schizophrenia spectrum patients. The results suggest that findings previously obtained with DSM-II schizophrenics concerning premorbid competence and role orientation can be generalized to DSM-III schizophrenics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Responsiveness of chronic schizophrenics and normals to social and nonsocial feedback.

This is an investigation of the effect upon learning (of a psychomotor task: depressing a bar in accord with a repetitive double alternation pattern) of feedback on performance from a human being or from a panel of lights in a population of schizophrenics as compared to hospitalized nonpsychiatric patients. It was anticipated that when the feedback was from the human, the schizophrenic would not be able to profit as much from the information as compared to the normals, and that paranoid schizophrenics would profit more than nonparanoid schizophrenics. In general, the hypotheses were supported. The results are discussed as to their theoretical implications. From Psyc Abstracts 36:01:3JQ06J. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Temporal lobe epilepsy and schizophrenia: Comparison of reaction time deficits.

Current theory suggests that temporal–limbic dysfunction is responsible for schizophrenic symtomatology. Such theory dovetails with many reports of a higher frequency of schizophreniform psychoses in temporal lobe epilepsy (TLE) than is found with other forms of seizure activity. To explore the possibility of a common neurological substrate for the 2 disorders, a variable foreperiod reaction-time task, on which early crossover has been found to be characteristic of many schizophrenics, was administered to 11 schizophrenics, 12 TLE patients, 9 generalized seizure patients, and 10 normal controls. Results show that only TLE and schizophrenic Ss showed an early crossover of regular and irregular preparatory interval gradients. Discussion focuses on the status of crossover as a marker variable, and relevant animal and human lesion literature is reviewed. (45 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive event-related potential correlates of schizophrenia.

Reviews findings relating schizophrenia to 4 event-related brain voltage potential components: contingent negative variation (CNV), N100, P300, and slow wave. Research indicates that schizophrenics manifest several cognitive event-related potential (ERP) abnormalities relative to control Ss, including a diminished CNV in warned reaction time (RT) paradigms during the warning stimulus–imperative stimulus interval. This CNV continues beyond presentation of the imperative stimulus as the postimperative negative variation (PINV). CNV attenuation may reflect a state marker of psychosis in acute schizophrenics, but it may serve as a trait marker regardless of current symptoms in more chronic patients. In contrast, the PINV may be more of a state marker for both acute and chronic patients. There is a pattern of P100–N100 reducing in acute schizophrenics that is not seen in chronic and paranoid patients, as well as evidence of an attenuated enhancement of N100 to stimuli presented in an attended channel, especially at slower event rates. A diminished late positive complex apparently due more to a diminished P300 than a diminished slow wave has been observed in schizophrenics, which may to a degree reflect a trait marker of high risk for schizophrenia as well as a residual deficit state that often remains following the remission of positive symptoms. With the possible exception of the PINV elicited in standard CNV paradigms, these ERP abnormalities do not appear to be specific to schizophrenia, as they are also found in association with a variety of other disorders. (5 p ref) (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Word meaning and sexual identification in paranoid schizophrenics and anxiety neurotics.

From psychoanalytic theory it is reasoned that the paranoid schizophrenic is one who has not made an adequate identification with the parent of like sex; other theoretical formulations presuppose a lack of identification with either parent. To test which of these hypotheses is valid, Osgood's Semantic Differential was used as a measure of identification (as established by Lazowick, 1955). It was given to a sample of hospitalized paranoid schizophrenics, an outpatient VA mental hygiene clinic sample of anxiety neurotics, and 2 control groups, hopsitalized TB patients and working people. The results indicated that the paranoid schizophrenic showed lack of identification with either parent. To some extent, this was true of the identification pattern of the neurotic group, but the latter also showed confusion of identification. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Overinclusive thinking and delusions in schizophrenic patients.

15 schizophrenics with paranoid delusions, 15 schizophrenics with no delusions, and a control group of 15 nonschizophrenic hospitalized patients were given the Benjamin Proverbs test, the Mill Hill Vocabulary Scale, and 3 of Babcock's psychomotor speed tests. As predicted, there was a significant relationship between the presence or absence of delusions, and overinclusive thinking, as assessed by the average number of words needed to explain the proverbs and 2 time scores. Overinclusive patients tend to have paranoid delusions. There was no significant relationship between retardation, as assessed by the Babcock tests, and the presence of delusions. This finding complements an earlier finding of Harris and Metcalfe (see 32: 719) that slowness in schizophrenic patients is specifically associated with inappropriate affect and a poor prognosis, and Payne's (see 37: 5499) finding that a group of chronic schizophrenics was not overinclusive. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive impairment in schizophrenic patients on event-related potentials component P300

There have been many reports on the Event-Related Potentials (ERPs) abnormalities, especially P300 amplitudes reduction, in schizophrenic patients. However the relationships between P300 abnormalities and schizophrenic subtypes have not been clarified. This study aims to investigate the relationships in a relatively large number of drug free schizophrenics. Seventy three unmedicated schizophrenic patients (45 males, 28 females) who met the DSM-III-R criteria for schizophrenia were tested. Twenty seven of the schizophrenics were paranoid type according to the DSM-III-R, 23 were undifferentiated, 19 were disorganized, 2 catatonic and 2 residual. Seventy three healthy controls were age and gender matched to the patient group. All the ERPs were recorded during auditory odd ball task. Stimuli consists of 2 kHz and 1 kHz tone bursts, and the respective probabilities of the rare and frequent stimuli were 0.2 and 0.8. They were presented random order. The duration of each stimulus was 90 msec with rise and fall times of 10 msec, and the intensity was approximately 70 dB SPL for all the stimuli. The inter-stimulus intervals were 1.7 +/- 0.1 seconds. The subjects were instructed to count the numbers of rare tones. The scalp EEGs were recorded from Ag-AgCl electrodes at 16 sites that referred to linked earlobes. P300 amplitudes reduction [F (1,144) = 39.33, p < 0.001] and P300 latencies prolongation [F (1,144) = 12.41, p < 0.001] were found in schizophrenic group as a whole. Lower amplitude of P300 was observed at both right and left temporal sites in the subjects with undifferentiated type and disorganized type. Although in the subjects with paranoid type, the reduction was recognized at left temporal region, reduced amplitude was not seen at right temporal site. While no relationships between P300 amplitudes, the score of BPRS and SAPS were detected, in the patient with paranoid type, significant negative correlation between P300 amplitudes and SANS total scores was observed (r = -0.425, p = 0.03) at Pz site. These results were discussed with respect to cognitive impairment of schizophrenia.     

Schizophrenic memory-search performance involving nonverbal stimulus properties.

Investigated schizophrenic memory-search performance by conducting a memory-search choice-reaction-time (CRT) task involving nonverbal stimulus properties (real-life sizes of items). Procedures were designed to diminish ambiguities concerning previous evidence of possible schizophrenic impairment in scanning and comparison operations involving memory-held items. Ss (aged 18–60 yrs) were 20 paranoid and 20 nonparanoid schizophrenics, 20 psychiatric controls, and 20 normal Ss. Results indicate that scanning and comparison operations proceeded at comparable rates among the schizophrenics and controls. On the other hand, rates of encoding the presented stimulation for a given trial (the trial's probe item) into a task-facilitative format proceeded at a slower rate among the paranoid Ss in particular. Discussion focuses on specific memory-search CRT paradigmatic conditions in which intact speed of memorial item comparisons tended to be most evident among these patients. Results resemble earlier observations of the present 2nd author (see record 1978-31872-001) on memory-search CRT performance among paranoid and nonparanoid schizophrenics when probe stimulation has remained in view throughout each trial. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reaction time, distractibility, and overinclusive thinking in psychotics.

Fifteen paranoid schizophrenics, 15 nonparanoid schizophrenics, and 15 nonschizophrenic psychiatric inpatients were given 3 of Babcock's tests of psychomotor retardation, and a test of overinclusive thinking based on Benjamin's proverbs. In addition, they took part in a simple and multiple-choice auditory reactiontime experiment in which the presence and number of distracting stimuli were varied. As predicted, the reaction times of the overinclusive patients were initially significantly slower. Overinclusive patients were also significantly more affected by the distraction, presumably because they are less able to filter out these irrelevant stimuli. A similar performance characterized those diagnosed as paranoid schizophrenic, as contrasted to those with other diagnoses, probably because of the significant relationship between paranoia and overinclusive thinking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sex bias in schizophrenia research: A short report.

Lack of consideration of possible sex differences among schizophrenics and a possible male bias was noted in a survey of 3 refereed journals publishing schizophrenia research. Studies in the Journal of Abnormal Psychology, the Journal of Nervous and Mental Disease, and the Archives of General Psychiatry often failed even to specify the sex composition of their schizophrenic samples. In addition, there was a tendency in 2 of these journals to use more male than female schizophrenic Ss. It is suggested that unattended sex differences among schizophrenics may influence both experimental results and sex composition of samples, thereby introducing a significant sex bias into schizophrenia research. Greater attention to differences between male and female schizophrenics is urged. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Size estimation, perceptual recognition, and cardiac rate response in acute paranoid and nonparanoid schizophrenics.

Studied perceptual response styles of 8 paranoid and 8 nonparanoid schizophrenics in a VA hospital using size estimation and perceptual recognition tasks. Eight alcoholic patients were used as controls. Only acute, actively psychotic, unmedicated schizophrenics were included. Heart rate responses were monitored during the performance of the tasks. Psychological task performance and concomitant physiological responses were analyzed and integrated. The size estimation results replicate earlier findings. During the perceptual recognition task, the paranoid Ss showed a unique "jump to conclusions" response strategy. Early responding and response rigidity was not found to be specific to paranoid schizophrenics. All schizophrenic Ss showed more large-magnitude heart rate response during both tasks. The relationship between perceptual responses and physiological responses differed among the groups. (45 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Creativity and schizophrenia: An equivalence of cognitive processing.

Two tests of creativity were given to 10 paranoid and 10 nonparanoid schizophrenics, 10 nonpsychotic psychiatric controls, and 10 normal Ss. Ss were aged between 18 and 50 yrs. Scores on vocabulary and similarities tests, as well as education, medication, marital status, socioeconomic background, and age, were examined. Results indicate that nonparanoid schizophrenics were significantly more creative than paranoids and psychiatric controls on one creativity measure, a graded level measure of the Alternate Uses Test. Also, nonparanoid schizophrenics produced a significantly higher percentage of "highly creative" responses than did normals. Nonparanoid schizophrenics also scored higher than the other groups on the Welsh Figure Preference Test, but this finding was found to be related to age rather than to schizophrenia. The superior performance of the nonparanoid schizophrenic is discussed in terms of the encouragement that a supportive, nonjudgmental testing environment provides. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Encoding of taxonomic word categories by schizophrenics

Administered to 20 chronic, undifferentiated schizophrenics and 20 paranoid schizophrenic controls the release-from-proactive-interference procedure as developed by D. D. Wickens. Word triads representing 8 conceptual categories were the to-be-remembered stimuli. Proactive interference release was clearly established for both schizophrenic subgroups. These findings are interpreted to imply that chronic, undifferentiated schizophrenics as well as paranoid schizophrenics encode the attributes of conceptual word class in memory. Previous failures of chronic schizophrenics to benefit from categorized to-be-remembered materials in recall tests are probably not the result of an encoding deficiency. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Conceptual level" vs. "conceptual area" analysis of object-sorting behavior of schizophrenic and nonpsychiatric groups.

The Rapaport modification of the Goldstein-Gelb-Weigl Object-Sorting Test is used on a sample of 37 pairs of paranoid schizophrenics and nonpsychiatric patients to determine if schizophrenic thought reflects a marked loss of ability to conceptualize on an abstract level; or, is a disorder of communication. On the basis of the test results, the following conclusions are drawn: "1)… our schizophrenic group demonstrated a loss of social communication without evidence of impairment in abstractive ability. 2) Differences in conceptualization in the object-sorting task were clearly more closely associated with estimated test intelligence and education than with the presence or absence of schizophrenia… ." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Paranoid schizophrenia: non-specificity of neuropsychological vulnerability markers

During stages of remission, patients with paranoid schizophrenia seldom show severe attentional or information-processing dysfunctions, except in cases of long-term chronicity. The diagnostic specificity of four putative psychological vulnerability indicators of schizophrenia - the Span of Apprehension, the degraded stimulus Continuous Performance Test (dsCPT), the degraded stimulus visual backward masking task and the Wisconsin Card Sorting Test (WCST) - was examined in a group of patients with paranoid schizophrenia. Since no single test seems to identify all patients, the use of a combination of measures may be a useful strategy. Accordingly, the four tests were administered to 18 paranoid schizophrenic patients, 18 depressed patients and 18 normal subjects. Paranoid schizophrenic patients could be distinguished from normal subjects primarily on the basis of their performance on the backward masking task and secondarily by the dsCPT and the WCST. Paranoid schizophrenic and depressed patients could be differentiated to some extent by their performance on an information-mask condition of the backward masking task. Thus, of the four measures studied, only the degraded stimulus backward masking appeared to be a specific indicator of paranoid schizophrenia.     

Fluid and rigid boundaries of paranoid and nonparanoid schizophrenics on a role-playing task

The concepts of fluid and rigid boundaries were assessed in an improvisational role-playing task in an attempt to differentiate paranoid from nonparanoid schizophrenics. Thirty-one schizophrenic patients divided into paranoid, intermediate, and nonparanoid groups were given an improvisational role-playing task. The resulting scenes were analyzed by Fluid Boundary and Rigid Boundary scales, which were developed on the basis of specific aspects of the physical and verbal representations of characters, objects, and settings. The hypothesis that variations in the disruption or emphasis of representational boundaries differentiate paranoid and nonparanoid symptomatology received support. Paranoid schizophrenics scored higher on the Rigid Boundary scale, i.e erecting and/or exaggerating physical and interpersonal boundaries; and nonparanoid schizophrenics scored higher on Fluid Boundary scale, i.e. showing fused and fluid representations of characters, objects, and settings. Improvisational role-playing seems to hold promise as a medium with diagnostic value.