Memory dysfunction can result from impairments along a continuum of information processing, from poor initial acquisition of information during learning to disturbed retrieval of stored memory when it is later needed to perform a task1. The heterogeneous nature of TBI-related memory impairment is well-known, and there is a critical need to better understand such disease heterogeneity in order to enhance diagnosis and therapeutic management2. Several subtypes of memory dysfunction after TBI have been identified3,4. First, some TBI survivors exhibit impaired memory acquisition/encoding (e.g., frontal system damage)5. Second, some exhibit impaired memory consolidation/storage impairment (e.g., prominent damage to temporal lobe systems6). Third, some show impairment in retrieval of information5,7. This heterogeneity results from the variable nature and severity of underlying brain trauma resulting from unpredictable mechanical forces2,8.