Individual differences in memory generalization - Project summary Memory allows us to remember specific details of past events. Memory also allows us to build complex knowledge and generalize to new situation, by integrating information acquired across several experiences. While hippocampus has been long known to support memory specificity, more recent interests have focused on the hippocampal role in memory integration and generalization. To what degree memory generalization relies on unique mechanisms, distinct from the ability to remember specific details, is a matter of much debate. Furthermore, specificity-generalization dissociations may exist along the long axis of the hippocampus, across the hippocampal subfields, or through hippocampal interactions with distinct cortical regions. A key challenge in resolving among current theories and designing new ways to test them is that generalization has been measured using a range of tasks, but whether they capture the same underlying mechanism has not been evaluated. Establishing a common denominator (or a distinction) across generalization studies is a critical step towards reconciling results from isolated lines of research and informing future research of hippocampal-based generalization. Individual differences provide a unique means to uncover the degree to which different tasks rely on shared or distinct underlying cognitive processes. In the proposed R03 Small Project Grant, participants (N=200) will complete a range of memory tasks, including several putative memory generalization and putative memory specificity measures typically used in different labs. The primary proposed analyses will reveal the degree to which distinct generalization tasks measure the same memory generalization capability and the degree to which memory generalization ability is dissociable from the ability to remember specific details. The work will yield a rich dataset that will be freely shared on Open Science Framework (or equivalent) platform and that can be queried for many questions. Easy-to-use and documented code for collecting each memory measure will be shared with the data for any lab to adopt. By establishing equivalency or distinctions among different memory measures, the results will support informed synthesis of existing work and facilitate crosspollination of ideas across labs. Dissociating specificity and generalization processes within each task and establishing validated generalization measures will pave way for future neuroimaging research testing current generalization theories. More broadly, the results will inform current theories of memory function and may help shed light on mixed patterns of memory specificity and generalization impairments in neurological diseases, anxiety, depression, autism, or following a stroke.
