Schemas, as memory representations of typical contexts, allow for generalization from previous experiences while often improving memory organization and accuracy. However, these advantageous characteristics of schematic memory may come at the cost of episode-specific information. In the human brain, this tradeoff between general and specific knowledge has been linked to differential contributions of the medial temporal lobes (MTL) to episode-specific memory and the ventromedial prefrontal cortex (vmPFC) to generalized, schematic memory. Here, we used a neuropsychological approach to test whether participants with focal vmPFC damage (n = 6) would show a reduced influence of schematic memory relative to healthy normal comparison participants (n = 12) in a recognition task that presented schematically congruent or incongruent contexts at study. As predicted, normal comparison participants were more likely to identify items as old after studying them in congruent contexts, and this effect was reflected in increased true and false recognition. These effects of prior context on recognition were not observed in the vmPFC group, suggesting that vmPFC damage reduced the influence of schematic memory. These findings are consistent with the proposition that the vmPFC plays an important role in integrating previous experience into ongoing memory processes while acting as part of a larger memory network.
Significance statement: In the human brain, new memories are strongly influenced by existing knowledge of relevant context (sometimes called "schemas"). Schemas can benefit memory by expediting learning and increasing capacity in familiar contexts, but these benefits may simultaneously reduce episode-specific memory. Here we show that damage to the human ventromedial prefrontal cortex (vmPFC) reduced the influence of existing knowledge on new memories. Our findings suggest that the vmPFC plays a key role in schematic memory processes by integrating previous experiences and contextual information to influence memory. These findings provide novel insight into the brain regions necessary for normal schematic memory and enhance our understanding of the brain networks supporting memory processes.
Keywords: contextual congruence; false recognition; schema; schematic memory; ventromedial prefrontal cortex; vmPFC.
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