The Mindful Brain [antikvár]

INTRODUCTION Francis O. Schmitt Neuroscience, the multidisciplinary study of the central nervous system, has expanded greatly during the last two decades both in numbers of investigators and in subjects being investigated at all levels of complexity, from that of molecules, brain cells, and brain systems to that of behavior. New discoveries and conceptual advances enliven the meetings of national and international societies of neuroscience. Highly sophisticated concepts of the function of various partial systems of the brain have been developed on the basis of ingenious experimental designs in anatomy, physiology, and other aspects of neuroscience. These advances are valuable and meaningful not only in their own right but as a basic foundation for a scientifically significant attempt to understand the most complex known mechanism, the human brain, and to achieve the highest ultimate aim, a comprehension of human selfhood and psyche. Many theories of higher brain function (learning, memory, perception, self-awareness, consciousness) have been proposed; but in general these lack cogency with respect to established anatomical and physiological facts and are without biophysical and biochemical plausibility. These theories usually rely heavily upon processes subserved by spike action potential waves traveling in hard-wired circuits of Golgi Type I neurons. Such circuits consist of neurons that are large enough to permit easy impalement by microelectrodes and that possess long axons forming tracts connecting processing centers in general regions of the brain that have been characterized as sensory, motor, associational, frontal, temporal, parietal, and occipital. Theories based on partial systems are subject, however, to the component-systems dilemma that bedevils all attempts at biological generalization. Such theories fail to articulate and effectively deal with the essence of the problem, which is the distributive aspect that emerges from the complex interaction of functional units such as neurons or neuronal circuits in the brain. Until now no detailed, self-consistent theory has been proposed that specifies and functionally characterizes the operational repertoires at the level of molecules, individual neurons, or groups (circuits) of neurons and that explicitly defines the postulated information-processing mechanism. I