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J Parnas

Publications and source records attributed to J Parnas.

At least 37 records · Page 2Linked to original sources

The influence of parental socioeconomic status on CT studies of schizophrenia.

A sample of 19 DSM-III-R schizophrenics and 94 controls with no mental illness from the Copenhagen high-risk project was used to test the hypothesis that social class of origin is related to adult CT measures of ventricular, sulcal, Sylvian fissure and anterior interhemispheric fissure enlargement, cerebellar pathology, and brain volume. The schizophrenics and controls were divided into high and low SES-of-origin. No significant differences emerged between the high and low SES-of-origin subjects within the schizophrenic and control groups on any of the six CT measures.

Adolescent↗

The concept of borderline conditions: a critical comment on validity issues.

It is pointed out that many published empirical studies on the issue of borderline conditions suffer from methodological shortcomings due to the prevailing empiricist simplification of research. Attention is drawn to the fact that the current psychiatric research in classification issues is dominated by an exaggerated quest for reliability at the expense of concern with validity issues. Concepts of operational criteria, polythetic-prototypic systems, and epistemic peculiarities of psychiatric, clinical typification are briefly exposed. It is suggested that future scientific progress in the area of personality research must take into account these general methodological considerations: repotentiate clinical-phenomenological observation, include prototypical approaches, extend studied samples with subjects drawn from the general population and import insights from personality trait research in normal psychology. Some of the claims of Gunderson and Torgersen (this volume) are discussed.

Borderline Personality Disorder↗

Developmental brain abnormalities in the offspring of schizophrenic mothers. I. Contributions of genetic and perinatal factors.

OBJECTIVE: We examined the contributions of genetic risk for schizophrenia and obstetric complications to brain morphological abnormalities in the offspring of schizophrenic and normal patents. METHODS: We used a cohort analytic study of 60, 72, and 25 individuals with neither, one, or two parents, respectively, who were affected with schizophrenia spectrum disorders, evaluated initially in 1962 when they were on average 15 years old, and reexamined from 1986 through 1989 with psychiatric interviews and computed tomographic scans of the brain. RESULTS: After controlling for the effects of age, gender, substance abuse, and history of organic brain syndromes and head injuries, there were significant stepwise, linear increases in cortical and ventricular cerebrospinal fluid-brain ratios with increasing level of genetic risk for schizophrenia. Genetic risk for schizophrenia also interacted with prospectively assessed birth complications in predicting selectively to enlargement of the ventricular system; ie, the effect of birth complications on ventricular enlargement was greater among those with two affected parents compared with those with one affected parent, and greater among those with one affected parent compared with those with normal parents. Perinatal exposure to ether anesthesia was associated with a generalized increase in brain abnormality, which varied in severity according to level of genetic risk for schizophrenia. CONCLUSIONS: The type and degree of brain abnormalities shown by adult offspring of schizophrenic and normal parents are strongly predicted by the independent and interacting influences of genetic risk for schizophrenia and obstetric complications. The findings further substantiate the hypothesis that structural brain abnormalities in schizophrenia are at least in part neurodevelopmental in origin.

Adolescent↗

Lifetime DSM-III-R diagnostic outcomes in the offspring of schizophrenic mothers. Results from the Copenhagen High-Risk Study.

OBJECTIVES: To perform a long-term prospective follow-up of children at high risk for schizophrenia to identify risk factors for the development of this disorder. DESIGN: Prospective follow-up population study of children of schizophrenic mothers and their matched controls from age 15 years to age 42 years, with multiple diagnostic assessments performed by senior clinicians using structured interviews blindly with respect to the group membership of the subject. PARTICIPANTS: Two hundred seven offspring of schizophrenic mothers and 104 control children without schizophrenic parents matched to the index group on age, sex, paternal socioeconomic status, urban/rural residence, and the amount of time spent during childhood in institutional rearing. MAIN OUTCOME MEASURE: The prevalence of the DSM-III-R disorders during the subjects lifetime. RESULTS: A significant aggregation of schizophrenia (16.2%) and other nonaffective, nonorganic psychosis (4.6%), and Cluster A personality disorders (21.3%) occurred among the offspring of schizophrenic mothers compared with the controls (1.9%, 0.9%, and 5%, respectively). No evidence of increased aggregation of (psychotic and nonpsychotic) affective disorders was noted among the offspring of schizophrenics. CONCLUSION: These results coincide with the results of other family studies in demonstrating a significant and specific familial aggregation of schizophrenia and nonpsychotic schizophrenia spectrum disorders among the biological relatives of schizophrenics.

Adolescent↗

Schizophrenic delusions: a phenomenological approach.

The issue of specificity of delusions in schizophrenia is still a matter of debate. The authors analyze the delusion formation in schizophrenia from a prototypical, phenomenological point of view, focusing on the subject's experience. This perspective links delusion formation to the autistic predisposition, which is considered here as the elementary phenotypic expression of the vulnerability to schizophrenia. Autism is viewed as a defective preconceptual (i.e., before language) attunement to the world. It impedes the individual's sharing of "common sense" with others and impairs the ability to project into the future. The development of delusions is illustrated, in part, by Klaus Conrad's work on the onset of paranoid schizophrenia. Delusions are viewed as transformations of the structure of experiencing. When threatened in future ability to be, the autistic, vulnerable person looks for the clues to becoming by attributing significance to disparate elements of the environment, which become self-referential. The link established between these disparate elements is based on universal characteristics that give the schizophrenic delusion a metaphysical quality. The transitivistic experience in delusions of control and omnipotence points to a specific way of crossing the border between "mine" and "yours" (disturbances of the experiencing "I"). What strikes a clinician in these delusions is that the normally tacit link between the sense of being and the sense of acting becomes quite apparent. The authors also propose a specificity in the themes of schizophrenic delusions. Delusions acquire a schizophrenic quality when ontological (i.e., universal) elements of the discourse between the locutor and the Other dominate at the expense of the worldly elements. It is emphasized that delusional content and form are dialectically related and hardly distinguishable. The authors consider the delusion formation as a phenomenon of emergence, a situation in which a new qualitative order arises from the reorganization of essentially unchanged elements. To consider schizophrenia as an emergent, particular way of experiencing, related to the autistic defect, has important consequences for research and for treatment. A dialectic exchange is needed between prototypical models generated by phenomenological inquiry and empirical, operational validation of testable aspects of such models.

Activities of Daily Living↗

Extending the phenotype of schizophrenia: implications for linkage analysis.

On the basis of simulation studies, we suggest that most existing designs for studying linkage in schizophrenia do not have sufficient power to detect a major contributing locus, even if one is present. For this reason, recent failures to replicate reports of linkage in schizophrenia are not surprising. Inclusion in the linkage design of phenotypes genetically related to schizophrenia, but more commonly found in the relatives of schizophrenics than schizophrenia itself, may increase the power of linkage analysis substantially.

Computer Simulation↗

Adult third ventricle width and infant behavioral arousal in groups at high and low risk for schizophrenia.

Previous research has demonstrated: (1) Subjects who are at genetic high risk for schizophrenia and who suffer delivery complications are at increased risk to evidence a widened third ventricle. (2) A widened third ventricle is related to decreased ANS arousal and, among schizophrenics, is related to negative symptom schizophrenia. (3) Adult schizophrenics evidence behavioral analogues of negative symptom schizophrenia premorbidly. This study compared adult CT scans to ratings of infant behavior in 179 subjects (104 at high genetic risk for schizophrenia) with the hypothesis that widened third ventricles would be related to underaroused infant behavior. Results of an ANOVA suggest that subjects who are at genetic high risk for schizophrenia and who evidence a widened third ventricle are more likely to have shown signs of behavioral underarousal as infants. Possible explanations, implications and limitations of the study are discussed.

Adolescent↗

A preliminary report on the neuropsychologic sequelae of human immunodeficiency virus.

The neuropsychologic sequelae of acquired immunodeficiency syndrome and human immunodeficiency virus were studied by comparing the results of a neuropsychologic test battery administered to the following three groups of Danish homosexual men: 20 patients with acquired immunodeficiency syndrome, 20 asymptomatic subjects who tested positive for the human immunodeficiency virus, and a matched control group of 20 subjects who tested negative for the human immunodeficiency virus. The group with acquired immunodeficiency syndrome performed significantly worse than the control subjects on the tests measuring concentration, memory, and psychomotor speed. The group with human immunodeficiency virus performed significantly worse than the control subjects on the tests measuring verbal memory and psychomotor speed. On the other tests, their results varied. The study supports the hypothesis that not only patients with acquired immunodeficiency syndrome but also asymptomatic subjects with human immunodeficiency virus may be neuropsychologically impaired early in the course of the disease.

AIDS Dementia Complex↗

Antecedents of predominantly negative- and predominantly positive-symptom schizophrenia in a high-risk population.

We reanalyzed the Copenhagen schizophrenia high-risk project data set to test recently developed models of the antecedents of predominantly negative and predominantly positive forms of schizophrenia. Among a group of 138 high-risk individuals, those at elevated genetic risk who suffered severe delivery complications and who were autonomic nonresponders during adolescence were significantly more likely than those without this pattern to evidence outcomes of schizophrenia with predominantly negative symptoms (86% vs 0.8%, respectively). Among a group of 160 high-risk subjects, those who escaped delivery complications, who evidenced a high degree of autonomic responsiveness in adolescence, and who experienced severe disruption of the early family rearing environment were significantly more likely than those without this pattern to evidence outcomes of schizophrenia with predominantly positive symptoms (40% vs 1.2%, respectively). In late childhood and early adolescence, predominantly negative-symptom schizophrenics were rated by their teachers as passive, socially isolated, and unresponsive to praise; predominantly positive-symptom schizophrenics were rated as overactive, irritable, distractible, and aggressive. The study is limited by the fact that the hypotheses were based in part on previous analyses of the same data set, by the small number of schizophrenic subjects of each subtype, and by the use of simplified theoretical and statistical models that do not address the multidetermination of negative and positive symptoms.

Adolescent↗

The Copenhagen High-Risk Study. Premorbid and clinical dimensions of maternal schizophrenia.

In a sample of 129 female schizophrenic patients followed for a period of 22 years, an analysis of intercorrelations between background, premorbid, and clinical variables was performed. Poor outcome, as measured by amount of hospitalization, was associated with premorbid psychopathic traits, defective premorbid social adjustment, early onset, and nonparanoid subtype of schizophrenia. Formal thought disorder, positive symptoms, and negative symptoms were positively intercorrelated. Schneiderian first-rank symptoms were predictors of better outcome and they were preceded by premorbid obsessive traits and lack of premorbid psychopathic and histrionic traits. These latter traits were predictive of early onset, nonparanoid schizophrenia. It is postulated that personality dimensions can exert a pathoplastic influence through their capacity to promote adaptive mechanisms. Negative symptoms seem to represent a conglomerate of various phenomena, some of which were preceded by premorbid schizoid traits.

Denmark↗

Genetic and perinatal determinants of structural brain deficits in schizophrenia.

Using a subsample from the Copenhagen schizophrenia high-risk project, we examined the contributions of schizophrenic genetic liability and perinatal complications to computed tomographic (CT) measurements of ventricular enlargement and cortical and cerebellar abnormalities. A factor analysis of six CT measurements yielded two significant factors. One factor reflected multisite neural deficits as evidenced by abnormality of the cerebellar vermis and widening of the sylvian and interhemispheric fissures and cortical sulci. The other factor reflected periventricular damage as evidenced by enlargement of the third and lateral ventricles. Because all of the subjects had schizophrenic mothers, the major source of genetic variation is contributed by the diagnostic status of their fathers. In a stepwise multiple-regression analysis, it was determined that the multisite neural deficits factor was significantly related to genetic risk for schizophrenia (as measured by schizophrenia spectrum illness in the subjects' fathers) but was unrelated to pregnancy or delivery complications or to weight at birth. Periventricular damage was highly and significantly correlated with the number of complications suffered at delivery, but only among subjects with an elevated genetic risk. Although limited by a small sample size, these results suggest that the two types of CT abnormalities in schizophrenia may reflect partially independent processes based on different combinations of genetic and perinatal influences.

Adolescent↗

Pre-morbid psychopathology in schizophrenia spectrum.

In a prospective, longitudinal study of high-risk offspring of schizophrenic mothers, of several dimensions of pre-morbid behaviour 'peculiarity' predicted subsequent schizophrenia or schizotypy. Peculiarity/eccentricity may represent a subtle marker of the schizophrenic genotype. 'Pre-schizophrenics', as compared with 'pre-schizotypes', were characterised by affective dyscontrol, reflected in less introverted and more disturbed behaviour.

Adolescent↗

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Education, Medical↗

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Germany↗

Assortative mating in schizophrenia: results from the Copenhagen High-Risk Study.

Assortative mating denotes a tendency for mated pairs to be more similar for some phenotypic trait (similar constitution) than would be the case if the choice of a partner occurred at random. Assortative mating occurs for a variety of physical (e.g., anthropometric variables) and psychological traits (e.g., IQ), including mental illness (Vandenberg 1972). Several studies have shown an excess of married couples suffering from a variety of psychiatric syndromes as compared to the frequency expected on the basis of noncontingent admissions into treatment facilities (Kreitman 1962, 1964, 1968; Nielsen 1964), a finding confirmed in a community study by Hagnell and Kreitman (1974). A recent review of the research literature (Merikangas 1982) concluded that there exists a true primary assortative mating for mental illness. This conclusion is strongly supported by the demonstration of an increased prevalence of mental disorders in the spouses' first-degree relatives (Slater and Woodside 1951; Guze et al. 1970; Cloninger et al. 1975; Gershon et al. 1973; Merikangas et al., in this issue.

Denmark↗

Heredity-environment interaction and schizophrenia.

The longitudinal prospective study of populations at risk is considered a powerful strategy towards disentangling hereditary and environmental factors. Data from Mednick and Schulsinger's 1962 study in Copenhagen, on children at high-risk for schizophrenia are used as an illustration. Pregnancy and birth complications, as well as institutional rearing in early childhood contributes towards schizophrenia in the risk children, but not in the low-risk controls. Risk children with an outcome of schizotypal personality disorder were hardly exposed to perinatal complications. To some extent, schizophrenia may be considered as a complicated form of schizotypal personality disorder, which again may be a genetically transmitted condition.

Adoption↗