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Working memory (WM) allows goal-relevant information to be encoded and maintained in mind, even when the contents of WM are incongruent with the immediate environment. While regions of heteromodal cortex are important for WM, the neural mechanisms that relate to individual differences in the encoding and maintenance of goal-relevant information remain unclear. Here, we used behavioral correlates of two large-scale heteromodal networks at rest, the default mode (DMN) and frontoparietal (FPN) networks, to understand their contributions to distinct features of WM. We assessed each individual’s ability to resist distracting information during the encoding and maintenance phases of a visuospatial WM task. Individuals with stronger connectivity of DMN with medial visual and retrosplenial cortex were less affected by encoding distraction. Conversely, weaker connectivity of both DMN and FPN with visual regions was associated with better WM performance when target information was no longer in the environment and distractors were presented in the maintenance phase. Our study suggests that stronger coupling between heteromodal cortex and visual–spatial regions supports WM encoding by reducing the influence of concurrently presented distractors, while weaker visual coupling is associated with better maintenance of goal-relevant information because it relates to the capacity to ignore task-irrelevant changes in the environment.

Auditory language comprehension recruits cortical regions that are both close to sensory-motor landmarks (supporting auditory and motor features) and far from these landmarks (supporting word meaning). We investigated whether the responsiveness of these regions in task-based functional MRI is related to individual differences in their physical distance to primary sensorimotor landmarks. Parcels in the auditory network, that were equally responsive across story and math tasks, showed stronger activation in individuals who had less distance between these parcels and transverse temporal sulcus, in line with the predictions of the “tethering hypothesis,” which suggests that greater proximity to input regions might increase the fidelity of sensory processing. Conversely, language and default mode parcels, which were more active for the story task, showed positive correlations between individual differences in activation and sensory-motor distance from primary sensory-motor landmarks, consistent with the view that physical separation from sensory-motor inputs supports aspects of cognition that draw on semantic memory. These results demonstrate that distance from sensorimotor regions provides an organizing principle of functional differentiation within the cortex. The relationship between activation and geodesic distance to sensory-motor landmarks is in opposite directions for cortical regions that are proximal to the heteromodal (DMN and language network) and unimodal ends of the principal gradient of intrinsic connectivity.

auditory semantic relatedness task

Jieyu Zhou,1,* Jiping Ding,2,* Xingkai Ma,3,* Meichao Zhang,2 Zirong Huo,1 Yuan Yao,2 Dong Li,2 Zhentao Wang1 1Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, People’s Republic of China; 2Department of Radiation Oncology, Shanghai Ninth People’s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People’s Republic of China; 3Department of Otolaryngology, Zhangjiagang First People’s Hospital, Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, People’s Republic of China*These authors contributed equally to this workCorrespondence: Dong Li; Zhentao Wang Email lidong@shsmu.edu.cn; 13916548333@163.comPurpose: Radioresistance is a vital obstacle for the prognosis of human nasopharyngeal carcinoma (NPC), but the underlying mechanism is still unknown. Here, we explored the role of the NRF2/KEAP1 pathway in radioresistance of NPC cell lines.Materials and Methods: We selected NPC cell lines CNE-1 and CNE-2, treated them with ionization, and subsequently determined the levels of NRF2, KEAP1, antioxidant enzymes, and ROS. We then evaluated the effect of NRF2 or KEAP1 inhibition on cell proliferation, colony formation, and radiosensitivity in CNE2 cells.Results: We discovered that the NRF2/KEAP1 signaling pathway can be activated by radiotherapy in NPC cells, while NRF2 knockdown enhances the sensitivity of CNE-2 cells to radiation treatment. In contrast, the silencing of KEAP1 inhibits the sensitivity of CNE-2 cells to radiation treatment.Conclusion: Our results suggest that NRF2/KEAP1 signaling may serve as an essential regulator of the radioresistance of NPC and may be applied as a novel therapeutic approach for the sensitization of NPC to radiation.Keywords: nasopharyngeal carcinoma, NRF2, KEAP1, radiosensitivity