Heat shock disrupts long-term memory consolidation in Caenorhabditis elegans.

Previous work has demonstrated that memory for habituation training is retained for > 24 hr in Caenorhabditis elegans. In this study the timing of memory consolidation was investigated by introducing heat shock (32 degrees C, 45 min) either before training, long after training, or during training. It was found that memory consolidation was disrupted by heat shock during training but not before or after training. In addition, heat shock before training failed to induce thermal tolerance to the effects of heat shock during training on long-term memory formation. When brief heat shock (32 degrees C, 15 min) was presented during training at different intervals, the results suggested that a narrow critical period for memory consolidation of habituation may exist. These findings demonstrate that in C. elegans long-term memory for habituation is disrupted by a temporally defined agent, heat shock. Therefore, heat shock can be used as a fine-grained tool to investigate the dynamics of memory consolidation.