Discrimination among temporal patterns of stimulation in a computer model of a coelenterate nerve net
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The simulated nerve nets used were able reliably to discriminate between many of the time patterns used. The factors entering into range and acuity of pattern discrimination by the net are identified.
The simulated nerve nets tended to support a greater spread of excitation in response to even temporal distribution of stimuli than in response to clustered distributions of stimuli under certain conditions. These conditions are specified.
The response measure which was used (“final spread”) is shown to give different results in some cases than either of two other measures (“average” spread for the seven stimuli and “maximum spread”).
The simulated nerve nets were able to produce reliable differences in the spread of excitation between certain patterns and their temporally mirror-image counterparts. The necessary conditions for such pattern recognition are described.
The relationships among the principal variables, namely the temporal distribution of stimuli, the specific sequence of junction decay rates, the magnitudes of facilitation decay rates, and their relative frequency distributions are described as they affect the spread of excitation in the nerve net. The overall finding that the net is able to discriminate between some temporal patterns gathers significance in that it represents an ability of the net to translate temporally coded information into spatial form. Thus, it is shown that already at the level of a simplified model of a coelenterate nervous system, the requisites for temporal to spatial translation are met.
KeywordsTemporal Distribution Decay Rate Temporal Pattern Response Measure Digital Computer
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