Overlapping functional systems: a theory for vertebrate central nervous system function in terms of informal systems analysis

The use of general systems theory as metatheory for developing and evaluating theories in the neurosciences

The general designations of neural systems and their levels of organization as presently applied in the neurosciences are described as being at variance with rigorous systems thinking. It is proposed that the rule-driven use of systems terminology and hierarchies would facilitate investigations of neural functioning in the natural case. General systems theory with its major propositions for hierarchical organization, open systems, and equifinality, is presented as providing the guidelines for developing systems-type theories for neuroscience investigations. General systems theory as metatheory is also used to evaluate hierarchies and systems designations in the neurosciences as these concepts are now applied in theories, models, and research. The metatheory is comprised of three sets of rules: the criteria for hierarchies; the properties of the open biological system; the criteria for the final conditions of open biological systems. The notion of the discovery of neural systems is contrasted with the apparent design of systems as frequently practiced by neuroscientists. The metatheory is summarized as directions for developing theories and as questions directed toward any neuroscience theory proposing levels of organization and systems.

A systems model of schizophrenic dysfunction

A review of pertinent literature suggests that central integrative, as opposed to peripheral, systems are primarily at fault in schizophrenia. More specifically, it is proposed that the central decision apparatus, defined as the subsystems which determine goals and end-states, is intermittently dysfunctional. This dysfunction, in turn, leads to a decoupling of the negative feedback system which normally aligns responses with the desired goal. The failure of these central systems is accompanied by an increase of diffuse activity within neural systems, semiautonomous activity on the part of subsystems, and a partial failure to regulate arousal systems. The paper closes with suggestions for future research in schizophrenia.