Functional Neural Architecture Supporting Highly Superior Autobiographical Memory

Background: The neural mechanisms of Highly Superior Autobiographical Memory are poorly understood. To shed light on the fMRI-informed neurobiology of this condition, in this study we characterise for the first time the neurofunctional architecture of a 20-year old individual (BB) with Highly Superior Autobiographical Memory and no concurrent neurological/psychiatric or other clinical conditions. Method: Relying on t-test inferential models comparing a single observation with a control group, we processed BB's resting-state fMRI signal and compared it with the neurofunctional architecture of 16 young adults with normal autobiographical memory. Specifically, we analysed large-scale brain networks, region-to-region functional connectivity and connectivity indices informed by graph theory. Results: BB 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 Highly Superior Autobiographical Memory 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 minimised thanks to automatic and accurate memory processing.