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PubMed1997

Evidence-based medicine and public health.

Much of the everyday work of public health professionals is concerned with the implementation of evidence-based medicine (EBM). Is this likely to improve the quality of the health service that patients' receive? In this paper, I argue that EBM is unlikely, by itself, to improve the dimensions of quality as defined by Maxwell (1994). This is because EBM relies on the individual doctor doing the right thing all of the time. Open systems theory is a way of looking at the influences of the environment on individual clinical behaviour. Using this perspective, it is easy to see why EBM will fail to improve patient care dramatically. The environment in which we work is a much bigger influence on us than we care to admit. I use some published examples to look at the way that the environment affects clinical behaviour to the detriment of the overall service quality. As public health professionals, we should be more concerned with the outcome of the service than with the specifics of a particular consultation. In this context, EBM is likely not to be a very useful tool for public health professionals.

Evidence-Based Medicine↗
PubMed1996

Single trial analysis of event related potentials: a comparison between schizophrenics and depressives.

The aim of the present paper was to perform a single trial analysis of event-related potentials in order to elucidate the mechanisms behind a reduced P300 amplitude occurring in unmedicated depressives (n = 11) and schizophrenics (n = 18). For this purpose, tools from linear system theory were applied to single trials in an oddball paradigm. This analysis provides estimates of the magnitude of the positive deflection occurring around the latency of P300 following target and nontarget simuli. According to the density functions of these amplitude distributions, we operationally defined "false-negative" (P300 amplitude lower than an individual threshold under target conditions) as well as "false-positive" responses (P300 amplitude higher than the threshold following nontarget stimuli). Our investigations revealed a reduction of the single-trial P300 amplitude in depression and a combination of amplitude reduction along with fewer elicited single-trial P300 waves in schizophrenics.

Adult↗
PubMed2005

Resilience in Arab American couples after September 11, 2001: a systems perspective.

Guided by a family resiliency model grounded in systems theory and social constructionism, we conducted in-depth interviews to explore how 18 Arab American couples living in New York and New Jersey perceived and dealt with the terrorist attacks and aftereffects of September 11, 2001. Results are organized around five themes: Making sense of the attacks; the social environment after September 11, 2001; construction of identity: Arab and/or American; how couples cope: reactions and resources; and immigration and acculturation. Clinical recommendations include helping couples to uncover and to explore conflicts in both Arab and American identities, using genograms to deal with family-of-origin histories, recognizing specific couple dynamics linked to traditional gender roles, helping couples connect to religious and cultural communities, and assessing acculturation.

Adaptation, Psychological↗
PubMed2004

Integration of kinetic information on yeast sphingolipid metabolism in dynamical pathway models.

For the first time, kinetic information from the literature was collected and used to construct integrative dynamical mathematical models of sphingolipid metabolism. One model was designed primarily with kinetic equations in the tradition of Michaelis and Menten whereas the other two models were designed as alternative power-law models within the framework of Biochemical Systems Theory. Each model contains about 50 variables, about a quarter of which are dependent (state) variables, while the others are independent inputs and enzyme activities that are considered constant. The models account for known regulatory signals that exert control over the pathway. Standard mathematical testing, repeated revisiting of the literature, and numerous rounds of amendments and refinements resulted in models that are stable and rather insensitive to perturbations in inputs or parameter values. The models also appear to be compatible with the modest amount of experimental experience that lends itself to direct comparisons. Even though the three models are based on different mathematical representations, they show dynamic responses to a variety of perturbations and changes in conditions that are essentially equivalent for small perturbations and similar for large perturbations. The kinetic information used for model construction and the models themselves can serve as a starting point for future analyses and refinements.

Models, Biological↗
PubMed2001

Hospitalized children with chronic illness: parental caregiving needs and valuing parental expertise.

Parents who care for a child with a chronic illness are forced to relinquish much of the control of the child's care when the child is hospitalized. By using the family systems theory as the underlying framework, the amount of control that parents of children with chronic illness wanted over their hospitalized child's care, and the degree to which parents felt health care professionals valued their expertise, was examined in a national sample of 50 parent caregivers. Participation in information sharing and technical care were areas over which parents wanted the most control. Nurses and attending physicians were rated highest in valuing parental expertise. Content analysis of an open-ended question on parental control revealed that parents felt a higher quality care was given at home than in the hospital; nurses were too busy or understaffed to provide optimal care in the hospital; and the child's control of care and decision making should increase as the child grew older.

Adolescent↗
PubMed1992

Clinical problem solving and the biopsychosocial model.

Engel's biopsychosocial model, while unifying the sciences relevant to medicine under general systems theory, is of limited utility in organizing bedside clinical problem solving. The authors consider this issue in light of the structure and goals of the clinical encounter. The biopsychosocial model is a model for organizing the sciences relevant to medicine; however, medical/psychiatric practice poses problems both within and outside the scientific realm. Since the biopsychosocial model cannot account for clinical problems to which the methods of science do not apply, the authors seek to facilitate biopsychosocial problem solving by proposing a clinical decision-making model that complements the biopsychosocial model. Their model directs the clinician's attention to three core aspects of the clinical encounter: problems of knowledge, ethics, and pragmatics. The authors reconsider Engel's case of Mr. Glover to demonstrate the anticipatory emphasis of the model. Other clinical examples are used to demonstrate the difficulties arising from mistaking one kind of aspect of medicine for another. When these three aspects of medicine are respected equally, a biopsychosocial practice is unavoidable.

Decision Making↗
PubMed2006

Feedback functions, optimization, and the relation of response rate to reinforcer rate.

The present experiment arranged a series of inverted U-shaped feedback functions relating reinforcer rate to response rate to test whether responding was consistent with an optimization account or with a one-to-one relation of response rate to reinforcer rate such as linear system theory's rate equation or Herrnstein's hyperbola. Reinforcer rate was arranged according to a quadratic equation with a maximum at a unique response rate. The experiment consisted of two phases, during which 6 Long Evans rats lever pressed for food. In the first phase of the experiment, the rats responded on six fixed-interval-plus-quadratic-feedback schedules, and in the second phase the rats responded on three variable-interval-plus-quadratic-feedback schedules. Responding in both phases was inconsistent with a one-to-one relation of response rate to reinforcer rate. Instead, different response rates were obtained at equivalent reinforcer rates. Responding did vary directly with the vertex of the feedback function in both phases, a finding consistent with optimization of reinforcer rate. The present results suggest that the feedback function relating reinforcer rate to response rate imposed by a reinforcement schedule can be an important determinant of behavior. Furthermore, the present experiment illustrates the benefit of arranging feedback functions to investigate assumptions about the variables that control schedule performance.

Animals↗
PubMed1990

Affects and cognitions of mothers and fathers of preterm infants.

This descriptive study examined the feelings and thoughts of mothers and fathers of preterm infants. Responses were solicited while the infant was in a special care nursery as well as in the home. Mothers and fathers responses between the hospital and the home setting were compared as were maternal and paternal responses. General systems theory was the conceptual orientation of this study. This framework provided a perspective on the generation and analysis of affective and cognitive responses of parents following the birth of a premature infant. An open-ended, semi-structured interview was conducted in the special care nursery when the infant was 5 days old. A second interview was conducted when the preterm infant had been home for 5 days. The 18 mother-father dyads wer interviewed twice as dyadic units. The dyads were married and shared the same domicile, spoke and understood English, and resided within eighty miles of the special care nursery. There were 11 males and 7 females in the infant sample, with a mean gestational age of 34.9 weeks and a mean birthweight of 2281.7. The interviews were content analyzed and responses of the parent dyads categorized into meaningful sets within an a priori construct of affects and cognitions. A z-statistic was used to examine differences in the proportion of responses. The affective category was comprised of both positive and negative responses. Positive responses were amazement, confidence, love, and well-being. Negative responses were anxiety, fear, helplessness, and sadness. The cognitive category was comprised of three kinds of responses: protection, provision, and attachment.

Adaptation, Psychological↗
PubMed1986

Family therapy workshops in the United States: potential abuses in the production of therapy in an advanced capitalist society.

A market for family therapy workshops has mushroomed in recent years. Treatment of families by therapists conducting such workshops, however, can be dispassionate and dehumanizing. Using the distinction between curing and healing, I do not question the curative potential of family therapy, but I question whether this kind of doctor/patient interaction promotes healing. Also, by demonstrating how the systems model tends to objectify patients and alienate therapists from those they treat, this paper challenges claims that family therapy recognizes the social nature of illness. The dehumanizing treatment cannot be attributed solely to the therapists, but requires further interpretation by analyzing the biases of the therapy model, the commodified context of the workshops, and epistemological issues arising from the application of general systems theory to a social model of treatment. Family systems therapy shares epistemological features with biomedicine, and like the biomedical model, alienates therapists from patients. This alienation, ironically, can be even greater when the family systems model is used than in biomedical treatment. Finally, I suggest that family therapy workshops have grown in popularity because the mechanistic features of the treatment model, drawn largely from cybernetics, promote the production and reproduction of a form of therapy compatible with the emphasis on 'functional health' favored in an advanced capitalist society.

Cybernetics↗
PubMed2006

Perirhinal cortical contributions to object perception.

The traditional theory of the medial temporal lobe (MTL) memory system asserts that the primate MTL (hippocampus, perirhinal, entorhinal and parahippocampal cortices) is exclusively involved in consolidating declarative memories. However, several recent reports have directly challenged this dogma by arguing that MTL structures also contribute to perception. Controversy remains as many of the behavioural tasks used have confounded memory with perception. We review the evidence here and highlight new studies in humans and macaques that indicate a perceptual role for MTL in the absence of such confounds. We argue that the challenge to MTL memory system theory is substantiated and that the implications are considerable, namely that most psychologists and neuroscientists have held a fundamentally flawed view of how memory is implemented in the brain.

Entorhinal Cortex↗
PubMed2003

The effect of spatial scale of resistive inhomogeneity on defibrillation of cardiac tissue.

Defibrillation of cardiac tissue can be viewed in the context of dynamical systems theory as the attempt to move a dynamical system from the basin of attraction of one attractor (fibrillation) to another (the uniform rest state) by applying a stimulus whose form is physically constrained. Here we give an introduction to the physical mechanism of cardiac defibrillation from this dynamical perspective and examine the role of resistive inhomogeneity on defibrillation efficacy. Using numerical simulations with rotating waves on a one-dimensional periodic ring, we study the role of the spatial scale of resistive inhomogeneity on defibrillation. For a rotating wave on a periodic ring there are three stable attractors, namely the uniform rest state, a wave traveling clockwise and a wave traveling counterclockwise. As a result, the application of a stimulus has the potential for three different outcomes, namely elimination of the wave, phase resetting of the wave, and reversal of the wave. The results presented here show that with resistive inhomogeneities of large spatial scale, all three of these transitions are possible with large amplitude shocks, so that the probability of defibrillation is bounded well below one, independent of stimulus amplitude. On the other hand, resistive inhomogeneities of small spatial scale produce a defibrillation threshold that is qualitatively consistent with that found experimentally, namely the probability of defibrillation success is an increasing function that approaches one for large enough stimulus amplitude. Extending these results to higher dimensions, we describe conditions for successful defibrillation of functional reentry with large scale spatial inhomogeneity, but find that elimination of anatomical reentry is quite difficult. With small spatial scale inhomogeneity, there are no similar restrictions.

Atrial Fibrillation↗
PubMed2002

Metabolic modeling: a tool of drug discovery in the post-genomic era.

The Human Genome Project, DNA microarrays, proteome chips and metabolic profiles, among others, are generating unprecedented amounts of valuable information about the genetic and metabolic responses of organisms to stimuli. This wealth of information poses a great scientific challenge, namely the development of novel, effective methods for functional analysis and interpretation. It is proposed here that biomathematical systems models must accompany data generation and management. A particularly effective framework for this purpose is canonical modeling based on Biochemical Systems Theory. The key concept of this theory is the formulation of biological phenomena as systems of differential equations, in which all processes are represented as products of power-law functions.

Biochemical Phenomena↗
PubMed2000

Opening caregiver minds: National Alliance for the Mentally Ill's (NAMI) provider education program.

The belief that poor parenting and dysfunctional families give rise to mental illness has been perpetuated by psychodynamic and family systems theories that lack supporting scientific evidence, and interventions based on these theories have failed to produce clinical improvements. Nevertheless the National Alliance for the Mentally III (NAMI) found that many clinical training programs continue to teach these outdated theories and interventions and that the mental health system is often destructive to family systems. This article describes a new 10-week program that is designed to educate service providers that will include families in the care of their chronically ill loved one. The program is based on a competence and adaptation rather than a pathology foundation and it shifts the discourse from causes to effects of illness.

Adaptation, Psychological↗
PubMed2001

Evolution and inequality.

Some scientists remain wary of evolutionary theory because of its supposed genetic determinism and insensitivity to the inequalities often associated with gender, race and class. Our aim is to show that such fears are outdated and to foster a role for evolutionary theory in public health. We use complex adaptive systems theory and the concept of a tradeoff between current and future reproduction to argue that when the future is objectively risky and uncertain the optimal reproductive strategy will often be to reproduce at a young age and/or high rate. Because reproducing early and/or often can lead to ill health and shortened lives, and because inequality is a major source of environmental risk and uncertainty, we argue that any attempt to use evolutionary theory to understand human reproduction, health or wellbeing must include considerations of inequality and social capital.

Adolescent↗
PubMed1995

Self-defense against verbal assault: shame, anger, and the social bond.

With many years of experience and refinement, the arts of self-defense against physical assault are highly developed. Without an effective theory and and a useful practice, there is little in the way of self-defense against verbal assault. For THEORY, I draw upon ideas from aikido, family systems theory, and the sociology of emotions. Since unacknowledged shame seems to generate rage and damage social bonds, I emphasize the management of shame, anger, and bonds. To illustrate the meaning of these principles, I offer several episodes as examples, using the METHOD of discourse analysis. I apply this theory and method to the PRACTICE of psychotherapy by describing some rudimentary principles of defense of self against verbal aggression, especially the subtle aggression of innuendo. Psychotherapy is often an arena of verbal aggression by both therapist and client, even though it is usually unintentional and outside of awareness.

Adult↗
PubMed2003

A general systems approach to suicide prevention: lessons from cardiac prevention and control.

The pathology of cardiac disease includes genetic, physical, biochemical, psychological, social, and environmental vectors. Factors contributing to suicide have been identified in these same areas. Survival from an acute cardiac event requires a systematized and multisectoral response. Communities that do not have systematized response capabilities to acute cardiac events have poorer survival outcomes. Suicide prevention and control may also be responsive to an integrated community response system. This paper examines the development of a community cardiac care model, explores potential parallels for a community suicide prevention and control model, and outlines a general systems theory framework for a suicide prevention and control system.

Community Mental Health Services↗
PubMed2001

Adolescent substance use and family-based risk and protective factors: a literature review.

Adolescent substance use has become a serious concern nationwide. Although there are many ways of viewing adolescent substance use, family influence has been established as one of the strongest sources of risk and protection. A review of the literature indicated relevant theories for understanding adolescent substance use and specific family-based variables influencing adolescent substance use. In general, there seems to be a relationship between adolescent substance use and family-based risk and protective factors. Relevant theories identified in the literature review include family systems theory, social cognitive theory, social control theory, and strain theory. Specific family-based risk and protective factors include family relationships such as with siblings and parents and family characteristics such as ethnicity and religious backgrounds. Future implications for research and prevention/intervention in relation to family-based risk and protective factors are discussed.

Adolescent↗
PubMed2000

Defining and measuring clinical processes using a dynamical systems approach.

We describe an approach to defining and measuring a clinical process and its components. The approach was developed subsequent to an attempt to measure the value of an Electronic Patient Medical Record System (EPMRS). To build our model, we assume the medical record is a communications channel and extend Shannon's model to include the clinicians' concepts, tasks, and tactics. We assumed the patient care process is a series of actions and explore the appropriate dimensions for describing patient care events. The extended model of communication and patient care events enumerates the dimensions for gathering data to measure physicians' use of patient medical information systems while caring for patients. The clinical process model may be constructed using dynamical systems theory, also known as chaos theory. Traditional statistical modeling is compared to dynamical system modeling to suggest which method may result in a better model of the patient care process.

Clinical Medicine↗