Biomedical subjects

P D Lopez

Publications and source records attributed to P D Lopez.

2 recordsLinked to original sources

PubMed1984

Computer programs as theories in biology.

Complex theories in biology may be developed, refined, and tested by the use of computer programmed simulations. The computer is recognized as a powerful tool for theory development; it is, in fact, the only means of thoroughly testing and examining a large and intricate theory. A program as a text is a statement of a theory and when run on the computer it is model of that theory. As the program's behavior is then the major argument for the credibility of a large and complex theory, the program itself is the only irrefutable statement of the theory. Bur programs written in the currently available programming languages tend to be incomprehensible. We argue that the program should be the definitive statement of the theory. In addition, the program plus a series of abstractions is a vehicle for effective communication of complex theories in biology. Several techniques of computer science are borrowed, for the purpose of developing a methodology for abstraction and a language for representing abstractions. The arguments are fully illustrated with a recently published biological theory.

Communication↗

PubMed1983

A neural theory of cognitive development.

A physiologically based model of the neocortex has been developed in an attempt to elucidate possible structural and functional mechanisms of the mammalian cortex and account for a wide range of low level cognitive behavior. The model has been constrained by diverse empirical data. At the level of structural details, neuroanatomical and neurophysiological data have been considered and at the level of gross behavior, psychological data has been used. From the theory that groups of reverberating neurons provide a short term memory mechanism and that primary drive reduction triggers consolidation of a memory, a mechanism for selective learning has been developed. Fundamental to the model is the postulate of a novelty drive mechanism that functions in a manner analogous to the more widely accepted primary drives (e.g. hunger and fear). This paper examines the novelty drive mechanism and demonstrates its utility in accounting for a wide range of habituation behaviors. The success of the model is evaluated by comparing its behavior to appropriate empirical data. Finally, it is argued that a computer program is both a theory and a model, and that important advantages accrue from such a viewpoint.

Animals↗