Critical role of the hippocampus in memory for elapsed time
Natalie Nguyen
Timothy Allen
Norbert Fortin2013
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Abstract
Episodic memory includes information about how long ago specific events occurred. Since most of our experiences have overlapping elements, remembering this temporal context is crucial for distinguishing individual episodes. The discovery of timing signals in hippocampal neurons, including evidence of "time cells" and of gradual changes in ensemble activity over long timescales, strongly suggests that the hippocampus is important for this capacity. However, behavioral evidence that the hippocampus is critical for the memory of elapsed time is lacking. This is possibly because previous studies have used time durations in the range of seconds when assessing hippocampal dependence, a timescale known to require corticostriatal circuits.
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Current biology : CB, 2018
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Highlights d Neuron loss in the mEC results in an impairment in the delayed alternation task d Hippocampal sequential cell activity during delay intervals is not required for WM d CA1 spatial discrimination during WM encoding is disrupted by mEC lesions d CA3 cells distinguish contexts despite the loss of mEC inputs
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