Propofol differentially modulates the consolidation of schema-related and -unrelated memory

Semantic relatedness of newly learned information to previous knowledge (i.e., a schema) leads to facilitated encoding and rapid integration into neocortical memory networks. The precise dynamics of this process in humans is still poorly understood. Here, we used the GABA-A-ergic anesthetic propofol to transiently suppress neural activity shortly after the encoding of schema-related and -unrelated verbal information in human patients. We found a significant difference in memory of schema-related and -unrelated words in patients that was absent in controls. This effect was driven by a benefit for schema-related words, thus suggesting that propofol administration facilitated the consolidation of previously encoded schema-related information. Our results suggest that schema-relatedness of newly learned information significantly influences the involvement of brain networks shortly after encoding. They further support the hypothesis of a competitive interaction between networks supporting schema-related and -unrelated memoranda during early memory consolidation.