Learning-related patterns of CA1 spike trains parallel stimulation parameters optimal for inducing hippocampal long-term potentiation.
Recent studies have revealed 3 stimulation parameters that together comprise the temporal pattern of neuronal activation optimal for the induction of hippocampal LTP: high-frequency bursts, activity 100-200 ms prior to a burst, and burst delivery in phase with the ongoing hippocampal theta rhythm. The present paper reports that these 3 aspects of patterned neural activity, collectively referred to as "theta-bursting," are characteristic of the spike trains of CA1 pyramidal cells in rats during the sampling and analysis of learning cues in an odor discrimination task and during performances of a spatial memory task. In contrast, theta-bursting occurs relatively infrequently during behavioral events less directly related to task-relevant mnemonic processing. These findings suggest that the optimal conditions for the induction of LTP occur naturally in behaving animals, time-locked to behavioral events critical to learning.
Otto
T
T
Department of Biological Sciences, Wellesley College, MA 02181.
Eichenbaum
H
H
Wiener
S I
SI
Wible
C G
CG
D000818:Animals; D004193:Discrimination Learning / Q000502:physiology; D004558:Electric Stimulation; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology; D006624:Hippocampus / Q000166:cytology / Q000502:physiology*; D007858:Learning / Q000502:physiology*; D017774:Long-Term Potentiation / Q000502:physiology*; D008568:Memory / Q000502:physiology; D009812:Odorants; D017966:Pyramidal Cells / Q000502:physiology; D051381:Rats; D013028:Space Perception / Q000502:physiology