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Near-saddle-node bifurcation behavior as dynamics in working memory for goal-directed behavior.

H Nakahara·K Doya
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Abstract

In consideration of working memory as a means for goal-directed behavior in nonstationary environments, we argue that the dynamics of working memory should satisfy two opposing demands: long-term maintenance and quick transition. These two characteristics are contradictory within the linear domain. We propose the near-saddle-node bifurcation behavior of a sigmoidal unit with a self-connection as a candidate of the dynamical mechanism that satisfies both of these demands. It is shown in evolutionary programming experiments that the near-saddle-node bifurcation behavior can be found in recurrent networks optimized for a task that requires efficient use of working memory. The results suggests that the near-saddle-node bifurcation behavior may be a functional necessity for survival in nonstationary environments.

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AnimalsBehaviorGoalsHumansMemoryModels, NeurologicalJournal ArticleResearch Support, Non-U.S. Gov't

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H Nakahara, K Doya. 1998-01-01. Near-saddle-node bifurcation behavior as dynamics in working memory for goal-directed behavior.. https://doi.org/10.1162/089976698300017917

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