A model for memory systems based on processing modes rather than consciousness

Abstract

Prominent models of human long-term memory distinguish between memory systems on the basis of whether learning and retrieval occur consciously or unconsciously. Episodic memory formation requires the rapid encoding of associations between different aspects of an event which, according to these models, depends on the hippocampus and on consciousness. However, recent evidence indicates that the hippocampus mediates rapid associative learning with and without consciousness in humans and animals, for long-term and short-term retention. Consciousness seems to be a poor criterion for differentiating between declarative (or explicit) and nondeclarative (or implicit) types of memory. A new model is therefore required in which memory systems are distinguished based on the processing operations involved rather than by consciousness.

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Figure 1: The declarative versus nondeclarative memory account.
Figure 2: Hippocampal connectivity.
Figure 3: A processing-based division among memory systems.

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Acknowledgements

The author would like to thank T. Reber, O. Markes, B. Meier and S. Duss for valuable help and discussions. K.H. is supported by Swiss National Science Foundation Grants 320000-114012 and K-13K1-119953.

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Henke, K. A model for memory systems based on processing modes rather than consciousness. Nat Rev Neurosci 11, 523–532 (2010). https://doi.org/10.1038/nrn2850

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