Cosmos and History: The Journal of Natural and Social Philosophy, Vol 10, No 1 (2014)

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Consciousness Began with a Hunter's Plan

Walter Freeman

Abstract


Animals search for food and shelter by locomotion through time and space. The elemental step is the action-perception cycle, which has three steps. In the first step a volley of action potentials initiated by an act of search (sniff, saccade, etc.) triggers the formation of a macroscopic wave packet that constitutes the memory of the stimulus. The wave packet is filtered and sent to the entorhinal cortex, where it is combined with wave packets from all sensory systems. This triggers the second step forming a unified memory that is passed through the hippocampal formation where it is assigned a place in the life-long memory of the subject. In the third step the output of the entorhinal cortex triggers the formation of a global wave packet that synchronizes the oscillatory activity of most of not all of the cerebral cortex. This shared oscillation caries a pattern of amplitude modulation, that can be observed non-invasively from the scalp EEG of human volunteers perceiving the stimulus and correlated with the stimulus. The same dendritic electric currents that drive the output of the brains of the wave packet drive the observed EEG signs. Therefore I postulate that the global wave packet, the third step in the cycle requiring only 0.2 seconds expresses the memory of the global accommodation that initiates the next action-perception cycle. Some unspecified fraction of the AM pattern is available to me the observer, and some other unspecified fraction of the total activity in the subject who is expected to respond to the stimulus. There is reason to hope that these fractions will coincide often enough to support refinements in techniques for extending these correlates of consciousness.

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