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PubMedDate not supplied

The cybernetic approach to the treatment of neurotic disorders.

This work is an attempt at a cybernetic analysis of the process of treatment of neurotic disorders. This approach is based on the consideration of a patient as an object of control. Assuming that the neurosis is an expression of some imbalance in an organism, the process of treatment is reduced to the exertion of influence on the system thrown out of balance (i.e., the patient) so that its homeostasis with the environment is restored. Thus the treatment of neurotic disorders consists of the use of negative feedback, both internal (those within the patients organism) and external (those within the system created by the interaction of patient and environment).

Adult↗

PubMed2001

A cybernetic theory of morality and moral autonomy.

Human morality may be thought of as a negative feedback control system in which moral rules are reference values, and moral disapproval, blame, and punishment are forms of negative feedback given for violations of the moral rules. In such a system, if moral agents held each other accountable, moral norms would be enforced effectively. However, even a properly functioning social negative feedback system could not explain acts in which individual agents uphold moral rules in the face of contrary social pressure. Dr. Frances Kelsey, who withheld FDA approval for thalidomide against intense social pressure, is an example of the degree of individual moral autonomy possible in a hostile environment. Such extreme moral autonomy is possible only if there is internal, psychological negative feedback, in addition to external, social feedback. Such a cybernetic model of morality and moral autonomy is consistent with certain aspects of classical ethical theories.

Cybernetics↗

PubMed1985

Cybernetic appropriateness review. Does it change physician hospital utilization patterns?

All hospital care can be characterized as either appropriate (i.e., efficatious and necessary) or inappropriate (i.e., services without benefit or services that could be provided in a less costly setting). A demonstration project combining an appropriateness determination methodology with a cybernetic control system was implemented in a study area that included six hospitals and approximately 400 practicing physicians. Project results to date indicate substantial improvements in the ratio of appropriate to inappropriate care for both hospitals and individual physicians. Evaluation research design problems and areas of future research are also discussed.

Cybernetics↗

PubMed1995

Mediatophore and other presynaptic proteins. A cybernetic linking at the active zone.

In rapidly transmitting synapses, the mediatophore, a protein located in the presynaptic membrane, seems to play a key role in the last step of transmitter release. Reconstituted either in proteoliposomes or in Xenopus oocytes, or transfected in particular cell lines, the mediatophore is able to release acetylcholine with characteristics which meet several typical features of transmitter release in natural synapses. Good correspondence between the two conditions was found for: i) the dependency of release upon calcium concentration; ii) the desensitisation of release by persistence of internal calcium; iii) the effect of several drugs; iv) the fleeting formation of a population of large intramembrane particles during the precise time of release; and v) the pulsatile or quantal nature of transmitter release. All these features therefore could well be ascribed to intrinsic properties of the mediatophore molecule. How is the mediatophore integrated in the whole presynaptic apparatus? To what extent is its function regulated by the other proteins of the active zone? These questions are far from being solved. We want nevertheless to propose here a general view in which characteristic presynaptic functions such as transmitter release, calcium entry, sequestration and extrusion, regulation of short- and long-term changes in release efficiency, are supported by an ordered succession of molecular events involving the proteins of the active zone. It will be seen that some proteins compete for a common binding site. It is thus expected that they will occupy this site in a regulated succession, according to simple cybernetic rules.

Animals↗

PubMed2003

Cerebellar ataxia: quantitative assessment and cybernetic interpretation.

To assess neuromotor disorders clinicians often rely on rating scales. Unfortunately, these scales lack the sensitivity and accuracy needed to detect the small changes in motor coordination that reflect the clinical progression of the disease on the basis of which treatment programmes can be adjusted. As a contribution to this topic, the present paper proposes a straightforward kinematic and kinetic analysis of reaching movements of patients with cerebellar ataxia in conjunction with a cybernetic interpretation of the data. The aim of the approach is to capture key deficits in the underlying motor control processes. We suggest that cerebellar ataxia may be characterized by defective feedforward control.

Cerebellar Ataxia↗

PubMed2002

Love-hate for man-machine metaphors in Soviet physiology: from Pavlov to "physiological cybernetics".

This article reinterprets the debate between orthodox followers of the Pavlovian reflex theory and Soviet "cybernetic physiologists" in the 1950s and 60s as a clash of opposing man-machine metaphors. While both sides accused each other of "mechanistic," reductionist methodology, they did not see anything "mechanistic" about their own central metaphors: the telephone switchboard metaphor for nervous activity (the Pavlovians), and the analogies between the human brain and a computer (the cyberneticians). I argue that the scientific utility of machine analogies was closely intertwined with their philosophical and political meanings and that new interpretations of these metaphors emerged as a result of political conflicts and a realignment of forces within the scientific community and in society at large. I suggest that the constant travel of man-machine analogies, back and forth between physiology and technology has blurred the traditional categories of the "mechanistic" and the "organic" in Soviet neurophysiology, as perhaps in the history of physiology in general.

Cybernetics↗

PubMedDate not supplied

Cybernetic modeling and regulation of metabolic pathways in multiple steady states of hybridoma cells.

Hybridoma cells utilize a pair of complementary and partially substitutable substrates, glucose and glutamine, for growth. It has been shown that cellular metabolism shifts under different culture conditions. When those cultures at different metabolic states are switched to a continuous mode, they reach different steady states under the same operating conditions. A cybernetic model was constructed to describe the complementary and partial substitutable nature of substrate utilization. The model successfully predicted the metabolic shift and multiple steady-state behavior. The results are consistent with the experimental observation that the history of the culture affects the resulting steady state.

Cell Culture Techniques↗

PubMedDate not supplied

Cybernetic model predictive control of a continuous bioreactor with cell recycle.

The control of poly-beta-hydroxybutyrate (PHB) productivity in a continuous bioreactor with cell recycle is studied by simulation. A cybernetic model of PHB synthesis in Alcaligenes eutrophus is developed. Model parameters are identified using experimental data, and simulation results are presented. The model is interfaced to a multirate model predictive control (MPC) algorithm. PHB productivity and concentration are controlled by manipulating dilution rate and recycle ratio. Unmeasured time varying disturbances are imposed to study regulatory control performance, including unreachable setpoints. With proper controller tuning, the nonlinear MPC algorithm can track productivity and concentration setpoints despite a change in the sign of PHB productivity gain with respect to dilution rate. It is shown that the nonlinear MPC algorithm is able to track the maximum achievable productivity for unreachable setpoints under significant process/model mismatch. The impact of model uncertainty upon controller performance is explored. The multirate MPC algorithm is tested using three controllers employing models that vary in complexity of regulation. It is shown that controller performance deteriorates as a function of decreasing biological complexity.

Algorithms↗

PubMed1989

Chronic occupational stressors, self-focused attention, and well-being: testing a cybernetic model of stress.

By using a cybernetic approach to occupational stress, it was hypothesized that the relationship between chronic work stressors and strain would be stronger among individuals high in private self-consciousness than among individuals low in private self-consciousness. Moderated regression analyses, using a sample of 135 blue-collar workers, revealed strong support for this hypothesis. This finding is antithetical to prior research showing that self-focused attention may buffer the effect of acute life events (Mullen & Suls, 1982; Suls & Fletcher, 1985). The results of the present study in conjunction with prior research suggest that the type of stressor (acute vs. chronic) examined may be a boundary condition influencing the direction of Stressor X Self-Focused Attention interactions. Implications for future research and stress management are discussed.

Adult↗

PubMed2000

Towards a control model for the highly cybernetic farming ecosystems.

A dynamic model based on the linear systems theory is developed in designing a highly cybernetic farming strategy to efficiently manage residuals generated in farm ecosystems. A linear cybemetic model would be used to describe the dynamic behavior of resource flow in the farm ecosystem in which the state variables are resource quantities, and the control variables are residual quantities. The controlled process is defined as the controlled management strategy change. Cybemetic mechanism shows the application of residuals as control measures have determinate effects on the controlled process as along as the farming system is observable and controllable in the control sense. To illustrate the model algorithm the idea is applied to simulate the dynamic response of residual phosphorus concentrations in an integrated pig/corn farming system located in the south Taiwan region. General results show that the residual phosphorous concentration is influenced by farming activities which are controlled by a system of gross input and net output parameters. This paper demonstrates using input-output analysis technique that residuals generated in the farming system is the most important cybemetic variable,

Agriculture↗

PubMed1999

Synergism of ergonomics, safety, and quality--a behavioral cybernetic analysis.

This report extends a control systems or cybernetic model of behavior to the behavior of groups of many individuals--organizations and institutions--operating together with technology as complex sociotechnical (ST) systems. The premise is that the level of quality in performance of a complex ST system is predicated upon the degree to which its organizational design incorporates elements of a closed-loop behavioral control system: control goals and objectives, sensory receptors, sensory feedback, learning and memory, effectors, and sensory feedback control. From a control systems perspective, ergonomics is essential to effective organizational self-regulation. If working conditions are poorly designed, work performance and safety and quality outcomes cannot be closely controlled. Conversely, as shown by field evidence, good design promotes synergism between ergonomics, safety, and quality as a closed-loop consequence of effective employee and organizational self-control of system performance, safety, and quality.

Cybernetics↗

PubMed1992

Nursing models in a special hospital: cybernetics, hyperreality and beyond.

Two emerging themes that resulted from research carried out in a special hospital on the use of nursing models are identified. The first theme to emerge was the tendency of the subjects to perceive the models as concrete entities thus undergoing a process of reification. The second theme identified was the adherence to the models outside the contextual nature of the setting which limited their effectiveness. A theoretical framework in which to locate the results of the study is explored using cybernetic learning theory and the notion of hyperreality, using the works of Jean Baudrillard. A method for innovation and changing practice in the special hospital setting is suggested.

Cybernetics↗

PubMed1987

The cybernetics of physical illness.

This is a speculative essay on the application of cybernetic concepts to the diagnosis and treatment of physical illness. The essay assumes that there is a unified biopsychosocial field in which the designation of illness as "physical" violates the ecological wholeness of the field. Although the field is complex, clinical intervention requires a degree of simplicity. This simplicity is sought by describing biopsychosocial experience in terms of recursive cycles. Clinical intervention is discussed as a disruption of recursive cycles.

Cybernetics↗

PubMed1979

Psychosomatic medicine and cybernetics.

In our daily psychosomatic medicine clinics, we have adopted four principles from Wiener's cybernetics and von Bertalanffy's general system theory. We use the polygraphic method for the diagnosis of psychosomatic disease (black box principle). For the control of psychosomatic symptoms, we use the biofeedback method (feedback principle). We use systematic desensitization to relieve social stresses which cause psychosomatic disease (open and closed system principle). And lastly, transactional analysis, which corresponds to the information and energy principle.

Biofeedback, Psychology↗

PubMed1975

Persecutory delusions: a cybernetic model.

The authors propose a cybernetic model for the formation and maintenance of persecutory delusions. During the formation of persecutory ideation, the threat of loss of control over the self or others interacts with predictions of control from others. This interaction may result in feelings of alien control followed by persecutory explanations. Since the persecutory explanations provide the individual with a new goal of resisting others' influence in order to prevent being controlled, they reduce the threat of loss of self-control. This is how persecutory delusions are maintained.

Cybernetics↗

PubMed1999

Cybernetics and consciousness.

This paper is a review of hypotheses of consciousness which arose from application of the theory of information and regulation and the cybernetic theory of mathematical machines in medicine. The author presents these hypotheses on the examples of his own works.

Brain Neoplasms↗

PubMed2000

[Image guided and robotic treatment--the advance of cybernetics in clinical medicine].

The introduction of advanced technology in hospitals has changed the treatment practice towards more image guided and minimal invasive procedures. Modern computer and communication technology opens up for robot aided and pre-programmed intervention. Several robotic systems are in clinical use today both in microsurgery and in major cardiac and orthopedic operations. As this trend develops, professions which are new in this context such as physicists, mathematicians and cybernetic engineers will be increasingly important in the treatment of patients.

Cybernetics↗

PubMed1976

Diagnosis of rheumatism by means of universal criteria, obtained by the cybernetic method.

With a view to establishing standardized criteria for the diagnosis of rheumatism suitable for widespread use in polyclinics and in large-scale epidemiological investigations, 3000 adults and children with rheumatism or one of seven similar diseases were subjected to multiple screening in eight centres in the USSR using a specially prepared standard card and standard methods. The information obtained was processed by cybernetic methods. Following determination of the sensitivity, specificity, and informational value of 486 signs of rheumatism, 68 of the most indicative signs were selected as criteria of rheumatism. These were included in the final table and weighted according to their indicational value both individually and in groups as syndromes. Using the table it is possible by simple calculation, without using a computer, to arrive at an objective evaluation of the reliability of the clinical diagnosis of rheumatism in patients with one of a group of eight similar diseases. The final diagnostic table was tested on 562 patients selected epidemiologically or from polyclinics or clinics and was shown to result in a high degree of diagnostic precision (higher than 95%).

Adult↗