Verbal memory network mapping in individual patients predicts postoperative functional impairments

Verbal memory decline is a significant concern following temporal lobe surgeries in patients with epilepsy, emphasizing the need for precision presurgical verbal memory mapping to optimize functional outcomes. However, the inter‐individual variability in functional networks and brain function‐structural dissociations pose challenges when relying solely on group‐level atlases or anatomical landmarks for surgical guidance. Here, we aimed to develop and validate a personalized functional mapping technique for verbal memory using precision resting‐state functional MRI (rs‐fMRI) and neurosurgery. A total of 38 patients with refractory epilepsy scheduled for surgical interventions were enrolled and 28 patients were analyzed in the study. Baseline 30‐min rs‐fMRI scanning, verbal memory and language assessments were collected for each patient before surgery. Personalized verbal memory networks (PVMN) were delineated based on preoperative rs‐fMRI data for each patient. The accuracy of PVMN was assessed by comparing post‐operative functional impairments and the overlapping extent between PVMN and surgical lesions. A total of 14 out of 28 patients experienced clinically meaningful declines in verbal memory after surgery. The personalized network and the group‐level atlas exhibited 100% and 75.0% accuracy in predicting postoperative verbal memory declines, respectively. Moreover, six patients with extra‐temporal lesions that overlapped with PVMN showed selective impairments in verbal memory. Furthermore, the lesioned ratio of the personalized network rather than the group‐level atlas was significantly correlated with postoperative declines in verbal memory (personalized networks: r = −0.39, p = .038; group‐level atlas: r = −0.19, p = .332). In conclusion, our personalized functional mapping technique, using precision rs‐fMRI, offers valuable insights into individual variability in the verbal memory network and holds promise in precision verbal memory network mapping in individuals. We used precision resting‐state functional MRI to map personalized verbal memory network (PVMN) for each treatment‐resistant epilepsy patient. PVMN, instead of group‐level functional atlases, effectively predicted post‐operative verbal memory impairments according to its spatial overlap with surgical lesions, indicating the precision PVMN mapping in individuals.