Brain overlapping system-level architecture influenced by external magnetic stimulation and internal gene expression in AD-spectrum patients.

The brain overlapping system-level architecture is associated with functional information integration in the multiple roles of the same region, and it has been developed as an underlying novel biomarker of brain disease and may characterise the indicators for the treatment of Alzheimer's disease (AD). However, it remains uncertain whether these changes are influenced by external magnetic stimulation and internal gene expression. A total of 73 AD-spectrum patients (52 with true stimulation and 21 with sham stimulation) were underwent four-week neuronavigated transcranial magnetic stimulation (rTMS). Shannon-entropy diversity coefficient analysis was used to explore the brain overlapping system of the neuroimaging data in these pre- and posttreatment patients. Transcription-neuroimaging association analysis was further performed via gene expression data from the Allen Human Brain Atlas. Compared with the rTMS_sham stimulation group, the rTMS_true stimulation group achieved the goal of cognitive improvement through the reconstruction of functional information integration in the multiple roles of 27 regions associated with the brain overlapping system, involving the attentional network, sensorimotor network, default mode network and limbic network. Furthermore, these overlapping regions were closely linked to gene expression on cellular homeostasis and immune inflammation, and support vector regression analysis revealed that the baseline diversity coefficients of the attentional and sensorimotor networks can effectively predict memory improvement after rTMS treatment. These findings highlight the brain overlapping system associated with cognitive improvement, and provide the first evidence that external magnetic stimulation and internal gene expression could influence these overlapping regions in AD-spectrum patients.