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PubMed2005

[Parental relationship from the perspectives of children, adolescents and clinicians. Development and clinical validation of the Parental-Representation-Screening-Questionnaire (PRSQ)].

The Parental-Representation-Screening-Questionnaire (PRSQ) is a new instrument designed to asses how children and adolescents evaluate their relationship with their parents. The aim of the questionnaire is to assess those aspects in the child-parent relationship that are crucial for a psychopathological risk. Conceptually, the PRSQ is based on cognitive self theory and systemic family theory. The PRSQ consists of 8 scales (36 items) for each parent: "freedom of decision", "emotional burden by the parents", "fears / overprotection", "conflict", "hostility / indifference", "aid for the parents", "punishment", and "support from the parents''. A clinic-referred consecutive sample of 152 patients of a Berlin child and adolescent psychiatry, aged 10 to 18 years, were surveyed. Adverse educational and psychosocial family factors were assessed by clinicians according to the fifths axis of the multiaxial classification system (MAS, Dilling et al. 2000). The internal reliability for 13 of the 16 scales ranges from .90 to .72. Factor analyses confirmed the factorial independence of six of the eight scales separately for mother and father. Moreover, adolescent girls reported significantly worse relations to both parents on five of the 16 scales than boys. Furthermore we found concordant correlations with the clinician's diagnosis of adverse educational and psychosocial family situations. The present results confirm the PRSQ as an economic and discriminating instrument to assess the representation of parent-child relation for clinical and for scientific purposes.

Adolescent↗
PubMed2001

Heart rate variability in ischemic heart disease.

Major untoward events, such as life-threatening arrhythmias and acute coronary events, have been suggested to be triggered by the activation of the autonomic nervous system in patients with coronary artery disease. Analysis of heart rate variability by conventional time and frequency domain methods, as well as by newer methods derived from nonlinear system theory, has offered a novel approach for studying the abnormalities in cardiovascular neural regulation in ischemic heart disease. Heart rate variability has been shown to be altered among patients with ischemic heart disease as compared to their age-matched controls without the evidence of ischemic heart disease. There are also obvious differences in various measures of heart rate variability between patients with uncomplicated coronary artery disease and those with coronary artery disease with complicated myocardial infarction. Impaired high-frequency oscillations of heart rate is the most prominent feature in patients with uncomplicated coronary artery disease, suggesting mainly an impairment in vagal autonomic regulation. Patients with prior myocardial infarction have a reduced overall heart rate variability, and a specific spectral pattern with a reduced low-frequency spectral component has been observed in patients with prior myocardial infarction and impaired left ventricular function. Recent studies have shown that the new nonlinear measures, particularly fractal analysis methods of heart rate dynamics, can detect subtle changes in heart rate behavior that are not easily detected by traditional analysis methods from ambulatory recordings. Patients with prior myocardial infarction have steeper power-law slope analyzed from the ultra and very low-frequency spectral bands, and they also have more random short-term heart rate dynamics analyzed by the detrended fluctuation method. A large body of data indicate that reduced overall heart rate variability is associated with an increased risk of mortality and nonfatal cardiac events in patient with ischemic heart disease. Of particular note, recent studies indicate that fractal analysis methods perform even better than the traditional analysis methods of heart rate variability as predictors of death and the onset of life-threatening arrhythmic events in post-infarction populations. These findings support the notion that heart rate variability analysis methods, such as fractal and complexity measures as well as conventional techniques, give valuable clinical information among patients with ischemic heart disease.

Autonomic Nervous System↗
PubMed1978

Conjoint marital therapy: a cognitive behavioral model.

This article presents an integrated cognitive-behavioral model for conjoint therapy of chronic marital discord. The model is based on eight empirically testable hypotheses that are clinically relevant and integrate contributions from general systems theory, behavioral marital therapy, and psychoanalysis. Disproof of cognitive schemas for the perception of the opposite sex (transference reactions) is hypothesized to be a common therapeutic mechanism in the dissimilar models of marital therapy.

Adult↗
PubMed2000

Impact of genetic testing for Huntington disease on the family system.

The psychological impact of DNA predictive testing on asymptomatic individuals at risk for Huntington disease (HD) has received considerable attention since the advent of the procedure in 1993. This study examined the impact of such testing on families from the families' perspective. Individuals asymptomatic at the time of testing, together with their families, were interviewed in their homes with a semi-structured interview. Eighteen families with a total of 55 individuals participated. Defining the family as the unit of analysis was consistent with Systems Theory that links interactions of individuals, families, and the social environment. Areas of affected family functioning noted by the respondents included: 1) family membership; 2) family patterns of communication; and 3) future care giving concerns as they influenced current relationships. Eighty-one percent of families experienced changes in family membership. Members in 50% of families experienced changes in patterns of communication, and 56% percent of persons reported changes in current relationships in response to test results and their implications for future caregiving. The data support the conclusion that genetic testing is a family, as opposed to an individual, matter and that family involvement in the decision making process should be strongly encouraged in order to help families adjust. The data imply that families will benefit in pre-test sessions from an examination of their patterns of dealing with illness issues, both past and present.

Adult↗
PubMed1997

Derivation of the linear-logistic model and Cox's proportional hazard model from a canonical system description.

The linear-logistic regression model and Cox's proportional hazard model are widely used in epidemiology. Their successful application leaves no doubt that they are accurate reflections of observed disease processes and their associated risks or incidence rates. In spite of their prominence, it is not a priori evident why these models work. This article presents a derivation of the two models from the framework of canonical modeling. It begins with a general description of the dynamics between risk sources and disease development, formulates this description in the canonical representation of an S-system, and shows how the linear-logistic model and Cox's proportional hazard model follow naturally from this representation. The article interprets the model parameters in terms of epidemiological concepts as well as in terms of general systems theory and explains the assumptions and limitations generally accepted in the application of these epidemiological models.

Communicable Diseases↗
PubMed1980

AVLT memory scores as a function of age among general medical, neurologic and alcoholic patients.

Analyzed data from the administration of the Rey AVLT to 232 general hospital patients according to age and type of diagnosis and influences of these variables on learning, recall and recognition. Aging has a different effect on these three test scores, depending on the classification of the patient. Non-organically impaired Ss had difficulties with recognition the older they were; Ss with ABS showed learning deficits; in CBS (alcoholic) Ss, aging was associated with poor recall performance, but not significantly. Younger, higher educated and more intelligent Ss have better recognition, whereas better learning is associated with only education as a factor. Analysis of these results was made in the context of storage system theory with further implications.

Acute Disease↗
PubMed1986

Family interaction patterns and locus of control as predictors of the presence and severity of anorexia nervosa.

Thirty female anorectics (mean age 26.4) and 30 female college student controls (mean age 25.3) completed a multidimensional locus of control scale, the Structural Family Interaction Scale, The Eating Attitudes Test, and a global clinical assessment measure. Three variables associated with Minuchin, Rosman, and Baker's (1978) family systems theory (overprotection, enmeshment, and rigidity) and one related to Bruch's (1973) theoretical position on anorexia nervosa (locus of control) were contrasted in terms of their relative effectiveness in predicting both the presence or absence and severity of the disorder. The best predictor of both measures in a series of regression and discriminant function analyses was locus of control orientation. The anorectics were significantly more external than the controls. The two groups did not differ on any of the family variables central to Minuchin et al.'s theory. The results support Bruch's contention that underlying anorexia nervosa is a sense of personal ineffectiveness.

Adult↗
PubMed2004

Impact on couple relationships of predictive testing for Huntington disease: a longitudinal study.

Since predictive testing has been available for Huntington disease (HD) and similar adult-onset neurodegenerative disorders, research into the psychosocial impact of test results has focussed on those receiving results, and to a lesser extent, on their partners. Few studies have examined the impact of predictive testing on the couple relationship, particularly from the perspective of family systems theory. This longitudinal study compared the level of marital adjustment of 23 couples in which the at-risk partner is undergoing predictive testing for HD (the testing group) with that of 20 couples in which the at-risk partner is not undergoing testing (the non-testing group). Participating couples completed a relationship measure, the Dyadic Adjustment Scale, at baseline and on two subsequent occasions. Using non-parametric tests, comparisons were made at each phase between the couple scores of the testing and non-testing groups but no significant differences were found in the levels of marital adjustment. Within the testing group the same comparisons were made for the carrier and non-carrier subgroups, and a significant difference was found at the final phase. There was an increase in the level of marital adjustment for the carrier group and a decrease for the non-carrier group. Together with trends observed in the data, this finding suggests a need for greater attention to be given to the potential impact of predictive testing on the couple relationship. Offering couples pre-result relationship assessment and referral for couple therapy, if warranted, may enhance the quality of professional support during the predictive testing process.

Adaptation, Psychological↗
PubMed2004

Couples' experiences of predictive testing and living with the risk or reality of Huntington disease: a qualitative study.

A qualitative study, based on family systems theory, was undertaken in order to gain a better understanding of the impact of predictive testing and of living with the risk or reality of Huntington disease (HD), on couple relationships. Semi-structured interviews were conducted with 14 couples; in 9 couples the at-risk partner had undergone testing, and of these, 4 were already affected with HD. At-risk partners in the remaining five couples had not been tested. Interview transcripts were analyzed to obtain a range of themes, which reflect the salient experiences of these couples in relation to HD. Most couples reported that receiving a predictive test result had little or no adverse effect on their relationship. However for two couples who separated after the at-risk partner received a non-carrier result, emotional factors associated with years of living with the HD risk, rather than the result itself, were regarded as having caused irreparable damage to the relationship. For two couples who have remained together since the diagnosis of one partner, loyalty was identified as the main factor contributing to the continuance of the relationship. The separations of the other two couples in which one partner was diagnosed were attributed to emotional distancing, and to the obsessive behavior of the affected partner. The findings of this study highlight both the individuality and the complexity of psychological effects on the intimate relationships of couples who live with the risk or reality of HD, and provide important insights for professionals offering support to these couples.

Adult↗
PubMed1989

Behavioral science space contributions.

In anticipation of longer missions on the space stations, Mir and Freedom, as well as a potential return to the Moon and the exploration of Mars, human survival and the quality of life aloft will be increasingly dependent upon research in the behavioral and biological sciences. This article reviews the possible contributions to space habitation of the behavioral sciences--especially anthropology, psychology, and sociology. Before space settlements become a reality, the author makes a case for the broadening of the engineering approach to human factor studies, and consideration of the integrative living systems theory in space planning and management.

Adaptation, Psychological↗
PubMed2003

Physician leadership: influence on practice-based learning and improvement.

In response to the technology and information explosion, practice-based learning and improvement is emerging within the medical field to deliver systematic practice-linked improvements. However, its emergence has been inhibited by the slow acceptance of evidence-based medicine among physicians, who are reluctant to embrace proven high-performance leadership principles long established in other high-risk fields. This reluctance may be attributable to traditional medical training, which encourages controlling leadership styles that magnify the resistance common to all change efforts. To overcome this resistance, physicians must develop the same leadership skills that have proven to be critical to success in other service and high-performance industries. Skills such as self-awareness, shared authority, conflict resolution, and nonpunitive critique can emerge in practice only if they are taught. A dramatic shift away from control and blame has become a requirement for achieving success in other industries based on complex group process. This approach is so mainstream that the burden of proof that cooperative leadership is not a requirement for medical improvement falls to those institutions perpetuating the outmoded paradigm of the past. Cooperative leadership skills that have proven central to implementing change in the information era are suggested as a core cultural support for practice-based learning and improvement. Complex adaptive systems theory, long used as a way to understand evolutionary biology, and more recently computer science and economics, predicts that behavior emerging among some groups of providers will be selected for duplication by the competitive environment. A curriculum framework needed to teach leadership skills to expand the influence of practice-based learning and improvement is offered as a guide to accelerate change.

Delivery of Health Care↗
PubMed2005

Drawing on mind's canvas: differences in cortical integration patterns between artists and non-artists.

Our primary question was to learn whether mentally composing drawings of their own choice produce different brain electric features in artists and laymen. To this purpose, we studied multichannel electroencephalograph (EEG) signals from two broad groups (all participants were females): artists (professionally trained in visual arts) and non-artists (without any training in art). To assess the underlying synchronization, which is assumed to be the platform for general cognitive integration between different cortical regions, three measures inspired by nonlinear dynamical system theory were applied as follows: (1) index based on generalized synchronization; (2) index based on mean phase coherence; and (3) index of phase synchrony based on entropy. Results consistent over all three measures were as follows: comparing the tasks to rest, the artists showed significantly stronger short- and long-range delta band synchronization, whereas the non-artists showed enhancement in short-range beta and gamma band synchronization primarily in frontal regions; comparing the two groups during the tasks, the artists showed significantly stronger delta band synchronization and alpha band desynchronization than did the non-artists. Strong right hemispheric dominance in terms of synchronization was found in the artists. In artists, the higher synchrony in the low-frequency band is possibly due to the involvement of a more advanced long-term visual art memory and to extensive top-down processing. The results demonstrate that in artists, patterns of functional cooperation between cortical regions during mental creation of drawings were significantly different from those in non-artists.

Art↗
PubMed1999

Knowing another from a dynamic systems point of view: the need for a multimodal concept of empathy.

This paper explores the concept of empathy within the context of current debate regarding the advantages of an intersubjective versus an intrapsychic focus on the treatment process. The author explores the way in which dynamic systems theory, the parent of intersubjectivity, can potentially embrace the wisdom of both relational psychoanalysis and ego psychology. The ongoing analytic discourse is represented in two modes, by schematic and symbolic representations, which roughly correspond to the intersubjective and the intrapsychic record. Empathy is redefined as the enactive, imaginal, and interpretive efforts an analyst makes toward understanding both the schematic and symbolic discourse with her patient.

Adult↗
PubMed2004

Rupert Riedl and the re-synthesis of evolutionary and developmental biology: body plans and evolvability.

This paper reviews the scientific career of Rupert Riedl and his contributions to evolutionary biology. Rupert Riedl, a native of Vienna, Austria, began his career as a marine biologist who made important contributions to the systematics and anatomy of major invertebrate groups, as well as to marine ecology. When he assumed a professorship at the University of North Carolina in 1968, the predominant thinking in evolutionary biology focused on population genetics, to the virtual exclusion of most of the rest of biology. In this atmosphere Riedl developed his "systems theory" of evolution, which emphasizes the role of functional and developmental integration in limiting and enabling adaptive evolution by natural selection. The main objective of this theory is to account for the observed patterns of morphological evolution, such as the conservation of body plans. In contrast to other "alternative" theories of evolution, Riedl never denied the importance of natural selection as the driving force of evolution, but thought it necessary to contextualize natural selection with the organismal boundary conditions of adaptation. In Riedl's view development is the most important factor besides natural selection in shaping the pattern and processes of morphological evolution.

Adaptation, Biological↗
PubMed1995

An approach to a biomathematical model of lymphocytopoiesis.

Fundamental principles for the development of a biomathematical model of lymphocytopoiesis are presented in this paper. The first step in this modeling approach is the definition of appropriate anatomical compartments in order to identify dominant locations of lymphocytes in the human body, and the definition of functional compartments in order to model different maturation stages. In the second step these compartment structures are combined, and thus form the basis of a dynamical model consisting of linear differential equations. Cell balance equations are used to derive the biomathematical dynamical model which is presented using the tools of modern systems theory. As a result of intensive discussions between engineers and medical doctors, our model of lymphocytopoiesis consists of six anatomical and six functional compartments. Virtual marking technique plays a key role for the interpretation of the simulation results which are in solid agreement with biological observations. Future work is directed towards implementation of radiation damages in order to meet the final goal, namely, the evaluation of our model against the data derived from a group of chronically irradiated uranium miners.

Biomarkers↗
PubMed1994

Statistical and dynamical analysis of circadian rhythms.

Time series of core temperature in golden hamsters with or without access to a running wheel were analyzed using statistical tools and Dynamical Systems theory. Although the statistical analysis did not show any striking difference between the two groups (other than clearer spectra in the case in the animals with access to wheels), a clear dynamical difference was found. The circadian temperature of hamsters with access to wheel running exhibited fewer degrees of freedom than those without access to them (1.728 vs 11.548). Thus, it may be argued that wheel running synchronizes the ciradian organization of hamsters.

Animals↗
PubMed1994

A method for filtering respiratory oscillations.

We present a method based on dynamical systems theory which can be used to filter time series in a way which is superior to classical Fourier decomposition. This method is applied to three data-sets, taken from respiratory measurements of two children in quiet and REM sleep. Our purpose is to filter the several different oscillatory mechanisms which operate, in order to provide clearer signals on which further analysis and diagnosis can be based.

Humans↗