Trends in Cognitive Sciences
Neurological disorders and the structure of human consciousness
Section snippets
Modularity of perceptual awareness
Neurophysiological evidence for the modular organization of perceptual awareness is strong. Rather than functioning as a general-purpose computing device, the brain consists of a network of adaptive systems 2, 11. Functional neuroimaging experiments, single-cell recordings and neuropsychological dissociations of function indicate that neural circuits segregate into functionally specialized systems on both cognitive and cellular levels, and reveal a robust correlation between the performance of
Integrated awareness emerges from modular interactions within a neuronal workspace
Although evidence for the modularity of information processing is strong, a modular architecture is not, in itself, sufficient to account for the majority of cognitive tasks that occur within the realm of conscious experience. The presence of a large-scale network, whose long-range connectivity provides a neural workspace through which the outputs of numerous, specialized, brain regions can be interconnected and integrated, provides a promising solution to this need for integration, and fits
Interpreting a post-lesion world
When considered within a framework of modular, interpreted consciousness, a variety of seemingly bizarre neurological syndromes reveal a rational pattern of symptoms. Although phenomenally distinct, such syndromes may be mechanistically related, with symptoms falling into place as the logical results of an interpretive system that is striving to make sense of an altered set of available information.
Conclusions
Data from a wide range of functional, physiological and clinical studies support a model of consciousness in which subjective awareness emerges from the interactions of specialized, modular components in a distributed neural network. In addition, the activity of such components is united cognitively by an interpretive process that occurs in the left hemisphere of the human brain. The dynamic, self-modifying nature of the interactions between these components is driven solely by the range of
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