Theta-Contingent Trial Presentation Accelerates Learning Rate and Enhances Hippocampal Plasticity During Trace Eyeblink Conditioning

摘要

Hippocampal theta activity has been established as a key predictor of acquisition rate in rabbit (Orcytolagus cuniculus) classical conditioning. The current study used an online brain–computer interface to administer conditioning trials only in the explicit presence or absence of spontaneous theta activity in the hippocampus-dependent task of trace conditioning. The findings indicate that animals given theta-contingent training learned significantly faster than those given nontheta-contingent training. In parallel with the behavioral results, the theta-triggered group, and not the nontheta-triggered group, exhibited profound increases in hippocampal conditioned unit responses early in training. The results not only suggest that theta-contingent training has a dramatic facilitory effect on trace conditioning but also implicate theta activity in enhancing the plasticity of hippocampal neurons.