Abstract
Producing and maintaining distinct (orthogonal) neural representations for similar events is critical to avoiding interference in long-term memory. Recently, our laboratory provided the first evidence for separation-like signals in the human CA3/dentate. Here, we extended this by parametrically varying the change in input (similarity) while monitoring CA1 and CA3/dentate for separation and completion-like signals using high-resolution fMRI. In the CA1, activity varied in a graded fashion in response to increases in the change in input. In contrast, the CA3/dentate showed a stepwise transfer function that was highly sensitive to small changes in input.
Publication types
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Research Support, N.I.H., Extramural
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Research Support, Non-U.S. Gov't
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Research Support, U.S. Gov't, Non-P.H.S.
MeSH terms
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Analysis of Variance
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Brain Mapping
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CA1 Region, Hippocampal / blood supply
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CA1 Region, Hippocampal / physiology
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CA3 Region, Hippocampal / blood supply
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CA3 Region, Hippocampal / physiology
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Dentate Gyrus / blood supply
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Dentate Gyrus / physiology
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Discrimination, Psychological*
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Hippocampus* / anatomy & histology
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Hippocampus* / blood supply
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Hippocampus* / physiology
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Humans
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Image Processing, Computer-Assisted / methods
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Magnetic Resonance Imaging*
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Memory / physiology*
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Oxygen / blood
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Pattern Recognition, Visual / physiology*
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Photic Stimulation / methods
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Reaction Time / physiology
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Transfer, Psychology / physiology*