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At least 145 records · Page 8Linked to original sources
PubMed1985

Confirmation of linear system theory prediction: Rate of change of Herrnstein's kappa as a function of response-force requirement.

Four human subjects worked on all combinations of five variable-interval schedules and five reinforcer magnitudes ( cent/reinforcer) in each of two phases of the experiment. In one phase the force requirement on the operandum was low (1 or 11 N) and in the other it was high (25 or 146 N). Estimates of Herrnstein's kappa were obtained at each reinforcer magnitude. The results were: (1) response rate was more sensitive to changes in reinforcement rate at the high than at the low force requirement, (2) kappa increased from the beginning to the end of the magnitude range for all subjects at both force requirements, (3) the reciprocal of kappa was a linear function of the reciprocal of reinforcer magnitude for seven of the eight data sets, and (4) the rate of change of kappa was greater at the high than at the low force requirement by an order of magnitude or more. The second and third findings confirm predictions made by linear system theory, and replicate the results of an earlier experiment (McDowell & Wood, 1984). The fourth finding confirms a further prediction of the theory and supports the theory's interpretation of conflicting data on the constancy of Herrnstein's kappa.

Journal Article↗
PubMed1976

A neural systems theory of schizophrenia and tardive dyskinesia.

Some systems ideas applied to individual persons are used to try to explain symptoms of schizophrenia and a syndrome of uncontrolled fragments of movement which sometimes occurs as a side effect of chronic, antipsychotic drug therapy. The behavior of normal organisms may be conceptualized in three echelons of control, with each successively higher echelon organizing, by selective disinhibition, semiautonomous, spontaneous fragments of activity which comprise the next lower echelon. It is hypothesized that schizophrenia involves a deficiency of inhibition by the frontal cortex, first echelon, on the corpus striatum, second echelon. This results first in insufficiently integrated fragments of behavior, and second in premature associative linkages among active elements. First echelon control develops as a normal person matures and gradually loses some of the playful activities of childhood. It is hypothesized that by disrupting certain aspects of activity in the corpus striatum, neuroleptic drugs reduce schizophrenic symptoms but also reduce the capacity of the second echelon to inhibit and integrate the smaller behavioral fragments wired into lower parts of the brain, third echelon. This results in uncontrolled movements. Though many researchers already favor the hypothesis that neuroleptic drugs act on the corpus striatum, the broader theory presented here is new and depends in large part on general living systems considerations. Emphasis is on conceptual decomposition of the integrated behavior of a whole organism into less complex subsystems. Individually, these have neither too much nor too little complexity to yield a plausible model. Some experimental predictions and predictions about possible therapies are made from the theory.

Corpus Striatum↗
PubMed1991

Rethinking levels of abstraction in family systems theories.

This article is an attempt to improve the way we conceptualize "levels" in family systems. The first section reframes thinking about levels by identifying an array of different ways of thinking about levels. The next section suggests a parsimonious frame-work for thinking about levels of abstraction in systemic processes. The proposed framework integrates several earlier ways of conceptualizing levels, and helps eliminate some of the confusion, inconsistencies, fragmentation, and limitations of some earlier models. The new framework has three categories that are called Levels I, II, and III. The most abstract level (III) includes phenomena such as family paradigms and values. The intermediate level includes processes such as second-order change, regime, and "meta" processes such as metacommunication and meta-rules. The least abstract level refers to specific processes such as transformation processes and rules. The article concludes with an attempt to demonstrate the usefulness of the proposed framework by showing how it can be used to eliminate a number of conceptual problems in earlier models, improve conceptual clarity, help generate new theoretical insights, and help deal with several controversies in the field.

Adaptation, Psychological↗
PubMed2003

Evidence-based decision-making in healthcare: exploring the issues though the lens of complex, adaptive systems theory.

Browman, Snider and Ellis have articulated several reasons as to why and how managers should address the implementation of evidence-based decision-making (EBDM) in healthcare. While their observations are acknowledged to be from the unique perspective of an oncology setting, this is a timely and welcome lead article with significance in other settings. The authors invite opinions on transferability, thus forming the basis of this commentary. In response, this commentary offers a number of supportive and differing views. Complex, adaptive systems (CAS) theory is first addressed as an appropriate lens to reframe our conceptualization of the health system. Then, in contrast to negotiation, dialogue through participatory planning and decision-making is introduced. Evidence-based decision-making (EBDM) and knowledge translation (KT) are expanded upon in the context of CAS and participatory environments. Finally, concrete suggestions are offered on how to structure multiple-stakeholder involvement in the decision-making process, including the growing role of consumers in the new complex, adaptive systems reality of healthcare.

Community Participation↗
PubMed1979

Conceptual frameworks and the philosophical foundations of general living systems theory.

The continued expansion and fragmentation of biological disciplines impede education, communication, and efficient advance of biological research. Reversing these trends may require a unification of theories and concepts from all levels of biological organization. One form of this unification is the statement of generalizations that apply to all living systems. We explore the philosophical foundations of general theories of living systems by analyzing conceptual frameworks as they apply to biology. This analysis examines the relation of empirical observation, theories, and conceptual frameworks within the context of an individual scientist's conceptual continuum. Also presented are a small set of translevel generalizations that articulate our conceptual framework of living systems in terms of organismic system organization, the environmental system-organismic system dyad, system capacity, and system incorporation. A set of procedural rules are stated which suggest minimum criteria for the evaluation of the explanatory adequacy of biological theories. The relation of this work to other similar analyses and syntheses of biological knowledge is discussed.

Animals↗