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PubMed1992

[Biosocial relations as contact points in the social network. A contribution to the theoretical discussion in psychosomatic medicine].

Psychosomatic medicine needs a theoretical model for clinical tasks and for research. To start from Freud's psychoanalytic theory (conversion and anxiety neurosis) and Alexander's model of the "vegative neurosis" a system theory concept of the bio-psychosocial model (Lipowski) is presented and discussed critically. Instead of further investigation on the problem of "unity", or on monistic or dualistic views of the mind-body problem, we propose a new theoretical approach. If we focus our interest on nodal points of the bio-psychosocial network we can learn more about somatic-psychosocial interaction and can develop practical consequences for research and clinical issues.

Anxiety Disorders↗
PubMed1989

A comparison of variant theories of intact biochemical systems. II. Flux-oriented and metabolic control theories.

In the past two decades, several theories, all ultimately based upon the same power-law formalism, have been proposed to relate the behavior of intact biochemical systems to the properties of their underlying determinants. Confusion concerning the relatedness of these alternatives has become acute because the implications of these theories have never been compared. In the preceding paper we characterized a specific system involving enzyme-enzyme interactions for reference in comparing alternative theories. We also analyzed the reference system by using an explicit variant that involves the S-system representation within biochemical systems theory (BST). We now analyze the same reference system according to two other variants within BST. First, we carry out the analysis by using an explicit variant that involves the generalized mass action representation, which includes the flux-oriented theory of Crabtree and Newsholme as a special case. Second, we carry out the analysis by using an implicit variant that involves the generalized mass action representation, which includes the metabolic control theory of Kacser and his colleagues as a special case. The explicit variants are found to provide a more complete characterization of the reference system than the implicit variants. Within each of these variant classes, the S-system representation is shown to be more mathematically tractable and accurate than the generalized mass action representation. The results allow one to make clear distinctions among the variant theories.

Biochemical Phenomena↗
PubMedDate not supplied

[Anxiety in the family].

The authors present the conceptual framework of the development and transmission of anxiety in the family system based on M. Bowen and general system theories. Anxiety is conceptualized as the reaction of family members to the disturbance in relational balance within the family system. The hypothesis that blurred boundaries within the family system are responsible for development, transmission and maintenance of anxiety in the family system is presented and supported with clinical examples. The ways of transmission of anxiety within the nuclear family and the phenomenon of transgenerational transmission are described. At the end the authors discussed practical implications of the presented theory for family therapy. Work with families with high level of anxiety should support the development of clear boundaries within the family system which leads to processes of separation and autonomy of family members.

Adolescent↗
PubMed2004

Some new directions in control theory inspired by systems biology.

This paper, addressed primarily to engineers and mathematicians with an interest in control theory, argues that entirely new theoretical problems arise naturally when addressing questions in the field of systems biology. Examples from the author's recent work are used to illustrate this point.

Biomedical Engineering↗
PubMed1976

Electrocochleography by mathematical modelling.

The aim of this work is to critically review some of the classical electrocochleographic methods in accordance with the systems theory: (a) in describing, by means of mathematical models, the different parts of the auditory system concerned in the generation of stimulus-evoked signals; and: (b) in comparing the outputs of these models with the measurements of the cochlear potentials. It must be stated clearly that we realise that many of the conclusions drawn could be criticised, it is hoped that future research in the field with be stimulated by this work.

Adaptation, Physiological↗
PubMed1999

A systemic and value-based approach to strategic reform of the mental health system.

Most writers now recognize that mental health policy and the mental health system are extremely resistant to real changes that reflect genuine biopsychosocial paradigms of mental disorder. Writers bemoaning the intransigence of the mental health system tend to focus on a small analytical level, only to find themselves mired in the rationalities of the existing system. Problems are acknowledged to be system-wide, yet few writers have used a method of analysis appropriate for systemic problems. Drawing upon the General System Theory (GST) analytical perspective, this article advances a systematic approach to understand the mental health system and to facilitate the development of reform strategies that recognize the system's complexity and changing nature. The article first discusses the failure of major reform efforts in the mental health system and the limitations of mainstream analysis of mental health politics and policies with respect to the objectives of analysis and reform. This article describes how systems thinking has thus far influenced the study of the mental health policy and politics system, and argues that a systemic perspective is profitable for reconceiving the mental health system, enabling a fresh basis for the development of reform strategies. The mental health system should be seen as a social system influenced by larger political and economic dimensions, not just as a 'delivery system' scientifically constructed by neutral experts. Furthermore, the policy planning process should be viewed as part and parcel of a mental health system modeled as complex and dynamic. The systemic perspective outlined here should help both to clarify the value-based objectives that we hold for the system and, consequently, to plan for the strategic reforms that have so far eluded us.

Canada↗
PubMed2000

Identification and psychic closure. A dynamic structuralist approach of the psyche

In this paper, the emergence of psychic structures is conceived within a dynamic structuralist framework, developed in dialogue with the semiotic and dynamic viewpoint on levels from evolutionary systems theory. If psychic structures emerge, it is because they are particular kinds of organizationally closed systems that interpret the variety from below (the biological level) for the level above (the social level). The mechanism of psychic closure is presented as the key mechanism for the constitution of psychic structures, and is interpreted in terms of identification: an identificatory judgment is a self-referential, closing judgment that involves a reinterpretation of the level below (the organic body) and is addressed to the level above (the fellow human being). The way in which identification has worked determines the kinds of psychic structures that are formed and also leads to different kinds of signifying practices. Different types of identification are discussed and a brief presentation of clinical arguments serves to illustrate the determinative role of identification in the formation of psychic structures.

Journal Article↗
PubMed1994

Social network and behaviour problems among 11-13-year-old schoolchildren. A theoretical and empirical basis for network therapy.

On the basis of theories concerning the relation of the social network to health and behaviour (e.g., social ecology, systems theory, and susceptibility theory), a theoretical model has been developed to understand the influence of the social network on children's behaviour problems in school. In western societies, children may participate in a number of different groups, such as the family, and school, neighbours, and so on. These groups may have different values, ideals and norms, etc. such differences may be assumed to promote the child's development, but they may also give rise to difficulties. The extent to which the persons in these groups know one another is assumed to be of vital importance in this regard. Contacts between the various persons in the different groups in the child's network are called spans and a network with a few of these is called a fragmented network. The main purpose of this study is to test the hypothesis that children with behaviour problems in school have fragmented networks. The networks of schoolchildren aged 11-13 years from various groups of schoolchildren from the general population (the main study comprised 190 boys and girls) were studied with the help of a method consisting of a network map of the children's everyday social networks, which they had to fill in. This method was tested by studying the relation of the network variables to the background variables, by means of comparisons with sociograms and classmates network maps, comparisons with information from the parents, by retesting and also by means of a structured interview with the children and a questionnaire sent to teachers and parents. The method was found to be usable for describing the child's 'inner picture' of its social network, which also seems to agree to some extent with the views held by other persons who know the child well. Rutter's teacher's questionnaire, after it was tested for validity and reliability under Swedish conditions, has been used as a screening instrument for behaviour problems in schools. The 32 children with behaviour problems in school, according to Rutter's teacher's questionnaire, were compared with the remaining 158. The findings support the hypothesis that was advanced--namely, that the problem children have fragmented networks. In view of the results obtained, which also support the theory advanced, a case study is reported concerning a model for clinical interventions in the form of network therapy for children with behaviour problems in school and who have fragmented networks.(ABSTRACT TRUNCATED AT 400 WORDS)

Behavior Therapy↗
PubMed2004

A theory of interactive parallel processing: new capacity measures and predictions for a response time inequality series.

The authors present a theory of stochastic interactive parallel processing with special emphasis on channel interactions and their relation to system capacity. The approach is based both on linear systems theory augmented with stochastic elements and decisional operators and on a metatheory of parallel channels' dependencies that incorporates standard independent and coactive parallel models as special cases. The metatheory is applied to OR and AND experimental paradigms, and the authors establish new theorems relating response time performance in these designs to earlier and novel issues. One notable outcome is the remarkable processing efficiency associated with linear parallel-channel systems that include mutually positive interactions. The results may offer insight into perceptual and cognitive configural-holistic processing systems.

Cognition↗
PubMed2004

What are symbols symbols of? Situated action, mythological bootstrapping and the emergence of the Self.

This paper addresses the question of how symbols should be understood in analytical psychology and psychoanalysis. The point of view examined focuses on the recent turn to more cognitive and developmental models in both disciplines and briefly reviews and critiques the evolutionary and cognitive arguments. The paper then presents an argument based on dynamic systems theory in which no pre-existing template or structure for either mind or behaviour is assumed. Within the dynamic systems model the Self is viewed as an emergent phenomenon deriving from the dynamic patterns existing in a complex system that includes the physiological characteristics of the infant, the intentional attributions of the caregiver and the cultural or symbolic resources that constitute the environment. The symbol can then be seen as a discrete, and in important ways an autonomous, element in the dynamic system. Conclusions are drawn for further research into the nature of the symbol with implications for both theory and practice in analytical psychology and psychoanalysis.

Ego↗
PubMed1990

Usefulness of information in bistable system and Dyson model for the origin of metabolism.

Useful or meaningful information for the transition between disordered and ordered states occurring in a chemical system, which organizes itself out of molecular chaos, is stochastically discussed from the viewpoint of dynamical system theory. To make the discussion perspicuous it is helpful to assume that the time evolution of the chemical system proceeds by a univariate, bistable one-step process of birth-and-death type. The model for the evolution of primordial metabolism proposed by Dyson is a bistable system, and hence this model answers the purpose of illustrating the usefulness of information.

Biological Evolution↗
PubMed2001

Self-consistent nonperturbative theory for classical systems.

We construct a self-consistent nonperturbative theory for the structure and thermodynamics of a classical system of particles that goes beyond the usual approaches based on perturbation theory. Our theory, which gives accurate predictions for the phase diagram, is based on two ingredients: first, use is made of an exact expression for the free energy of a many-body system in terms of a reference system and a coupling integral connecting the latter to the final system; second, correlation functions may be very accurately approximated using a number of sum rules relating the radial distribution function with thermodynamic quantities. Consistency between the coupling integral expression and the sum rules may be achieved by means of a self-consistent process.

Journal Article↗
PubMed1990

Sleeping and waking states in infants: a functional perspective.

There is little agreement on sleep-wake state categories for describing infants, nor is there agreement on how states are to be conceptualized. We propose General Systems Theory as a perspective for viewing behavioral states and for describing their function as a behavioral system within the infant's larger social system. In the social context, states provide communicative cues, mediate perception of caregiver stimuli, and modulate the infant's responses to those stimuli. Thus, states reflect the infant's CNS status and they are related in a complex, dynamic way to the developmental course of that status. A taxonomy of infants' behavioral states is described, composed of ten Primary States: Alert, Nonalert Waking, Fuss, Cry, Drowse, Daze, Sleep-Wake Transition, Active Sleep, Active-Quiet Transition, and Quiet Sleep. Using combinations of these states, a set of six Derived States is also defined. Results of naturalistic studies of infants' states are described to demonstrate for each of these states: reliability of measurement, evidence for concurrent and predictive validity, and unique intraperson correlation patterns. The findings support the usefulness of this state taxonomy for describing infants and for investigating the functions of state. Categorical and conceptual differences with the states as viewed by Wolff and Prechtl are discussed.

Humans↗
PubMed2000

Falsification of matching theory's account of single-alternative responding: Herrnstein's k varies with sucrose concentration.

Eight rats pressed levers for varying concentrations of sucrose in water under eight variable-interval schedules that specified a wide range of reinforcement rate. Herrnstein's (1970) hyperbolic equation described the relation between reinforcement and responding well. Although the y asymptote, k, of the hyperbola appeared roughly constant over conditions that approximated conditions used by Heyman and Monaghan (1994), k varied when lower concentration solutions were included. Advances in matching theory that reflect asymmetries between response alternatives and insensitive responding were incorporated into Herrnstein's equation. After fitting the modified equation to the data, Herrnstein's k also increased. The results suggest that variation in k can be detected under a sufficiently wide range of reinforcer magnitudes, and they also suggest that matching theory's account of response strength is false. The results support qualitative predictions made by linear system theory.

Animals↗
PubMed1985

Euler buckling in a wheelbarrow obstacle course: a catastrophe with complex lag.

This article studies human physical work capacity under increasing load from a general systems theory perspective. There are several points of generalization between the structure of nonliving (building materials) and living systems (humans) with respect to stress, strain, and fatigue. A catastrophe model for Euler buckling was transposed and tested for human performance in a wheelbarrow obstacle course under varying loads. Subjects were 129 employees of a Midwest manufacturing plant. A cusp model was hypothesized and verified (R2 = .68, control R2 = .11) where vertical load was the asymmetry factor, and body balance, height, and sex-related differences all contributed to bifurcation. A catastrophe model in codimension 10 was also invoked to explain memory in the system. Principal control variables were exercise habits, weight, balance, and sex-related differences (R2 = .75). The core model of human load-to-failure was concluded to be similar to that for Euler buckling: additional complexities were discovered which were attributed in part to systemic memory. Discussion points included the use of large dimension catastrophe models for problems involving complex lag effects, and the transposability of the model to the organizational systemic level.

Adipose Tissue↗
PubMedDate not supplied

Chemical plasticity of visual cortical neurons in integrative organization of feeding behavior in cats.

The P.K. Anokhin conception of organization of systemic behavior was used to study the discharge activity and chemical plasticity of cortical neurons in a goal-directed behavior. Chemical sensitivity of neurons in the visual cortex of instrumentally conditioned cats was studied during successive stages of food procuring and consuming. The results showed that definite stages of this integrated behavioral act are characterized by differences in the chemical sensitivity of visual neurons to neurotransmitters. The largest number of neurons resistant to neurotransmitters was found among cells that did not respond at successive stages of goal-directed behavior. The iontophoretic delivery of cycloheximide and lyzilvasopressine altered the discharge activity of individual cortical neurons at different stages of stereotyped instrumental conditioned acts. This suggests that the integrative organization of the feeding behavior is determined by chemical plasticity of the brain's visual cortical neurons and is dependent upon the processes of protein synthesis. According to the functional system theory (Anokhin, 1974) each brain neuron is included, by various degrees of freedom, in the stages of systemic organization that underlie the goal-directed behavior. Thanks to the plastic reorganization of brain units, each stage is directed toward the achievement of useful adaptive results for the organism during interaction with different environmental factors (Adrianov, 1993; Fadeev, 1988). It may be proposed that the reorganization of discharges of brain neurons that occurs at different stages of activity is due to changes in their chemical capacities. In concordance with such a hypothesis, the purpose of the present investigation was to study the chemical sensitivity of single visual cortical neurons to neurotransmitters at different stages of systemic organization of feeding behavior. The influence of protein synthesis inhibitors on the sensitivity of cortical neurons was also investigated.

Acetylcholine↗
PubMed1985

Tracer measurements of non-equilibrium volumes of distribution.

According to conventional theory the product of the transport flowrate and the mean transit time of a tracer through a system yields the equilibrium volume of distribution for the tracer, regardless of tracer kinetics or space geometry. Experimental results do not support this notion. The influence of measurement time on the volume measured with a bolus technique is addressed using systems theory to analyze a tissue-impedance form of the Sangren-Sheppard model. Assymptotic solutions show that the volume estimates are governed by a time constant, tau, related to diffusion in the tissue, to tissue capacity, and to wall permeability, and by a dimensionless ratio, f, describing a relation of tau to vascular transport time. A third parameter, g, describing the relative contributions to overall resistance to diffusion of effective permeability and of limited diffusivity in the tissue, is shown to be of less importance. The derived tau is similar to but not equivalent to the often cited "characteristic time". The "equilibrium" volume of distribution is defined as that which would be measured if equilibrium were allowed to establish. The "non-equilibrium" volume of distribution is defined as that which would be measured given finite times and is shown to approach the "equilibrium" volume as such times increase. Tracer equilibration is not required to accurately measure the "equilibrium" volume. When there is no flow limitation (f much less than 1) a measurement time of tau (plus vascular transit time) would yield a "non-equilibrium" volume only 33% of the "equilibrium" volume; a time of 2 tau would yield 55%; a time of 10 tau would yield effectively the total equilibrium volume. Finite diffusivity in tissue and permeability restrictions can have significant effects on the proportion of the volume measured.

Blood Flow Velocity↗
PubMedDate not supplied

Filling in the helper-gap: the intentions of frail older widows.

Despite marked interest in continuity of care and transitions experienced by older persons, there is little information available about the intentions of older women regarding changes that occur in their support networks. This article reports the findings of a descriptive phenomenological study of older widows' experience of home care and describes the experiences of 10 women who lost a key helper during the 3-year study. Compared with theories of continuity of care or transition, the findings are in keeping with the focus of nonequilibrium systems theory: bringing order out of disorder. Findings imply the need for holistic nursing interventions with older women who hope to continue living alone for as long as possible.

Activities of Daily Living↗