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Rapid Encoding of New Memories by Individual Neurons in the Human Brain.

ABSTRACT: The creation of memories about real-life episodes requires rapid neuronal changes that may appear after a single occurrence of an event. How is such demand met by neurons in the medial temporal lobe (MTL), which plays a fundamental role in episodic memory formation? We recorded the activity of MTL neurons in neurosurgical patients while they learned new associations. Pairs of unrelated pictures, one of a person and another of a place, were used to construct a meaningful association modeling the episodic memory of meeting a person in a particular place. We found that a large proportion of responsive MTL neurons expanded their selectivity to encode these specific associations within a few trials: cells initially responsive to one picture started firing to the associated one but not to others. Our results provide a plausible neural substrate for the inception of associations, which are crucial for the formation of episodic memories.

SUBMITTER: Ison MJ

PROVIDER: S-EPMC4509714 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Rapid Encoding of New Memories by Individual Neurons in the Human Brain.

Ison Matias J MJ Quian Quiroga Rodrigo R Fried Itzhak I

Neuron 20150701 1

The creation of memories about real-life episodes requires rapid neuronal changes that may appear after a single occurrence of an event. How is such demand met by neurons in the medial temporal lobe (MTL), which plays a fundamental role in episodic memory formation? We recorded the activity of MTL neurons in neurosurgical patients while they learned new associations. Pairs of unrelated pictures, one of a person and another of a place, were used to construct a meaningful association modeling the ...[more]

PMID: 26139375

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