Background: The neural mechanisms of highly superior autobiographical memory (HSAM) are poorly understood. To shed light on the functional magnetic resonance imaging (fMRI)-informed neurobiology of this condition, in this study we characterize for the first time the neurofunctional architecture of a 20-year-old individual (B.B.) with HSAM and no concurrent neurological/psychiatric or other clinical conditions. Materials and Methods: Relying on t-test inferential models comparing a single observation with a control group, we processed B.B.'s resting-state fMRI signal and compared it with the neurofunctional architecture of 16 young adults with normal autobiographical memory. Specifically, we analyzed large-scale brain networks, region-to-region functional connectivity, and connectivity indices informed by graph theory. Results: B.B. showed higher expression of large-scale and region-to-region connectivity, larger segregation of the pallidum and enhanced centrality of the temporal pole, orbitofrontal cortex and cerebellar lobule IX. Conclusion: These findings indicate that HSAM is associated with increased expression of neural pathways that support memory encoding, retrieval, and elaboration, but also with reduced expression of patterns typically involved in information control and metacognition, the use of which would be minimized thanks to automatic and accurate memory processing.
Keywords: autobiographical-memory network; calendar calculator; default-mode network; graph theory; resting state; salience network.