Mild cognitive impairment (MCI) describes an intermediate stage from normal cognitive functioning to dementia, and identifies a spectrum of diseases that includes impairment in both memory and non-memory cognitive domains. Our focus is to develop and test novel, individualized, multifocal, physiology-inspired non-invasive brain stimulation (NIBS) approaches aimed at enhancing interregional processing in cognition-related fronto-parieto-cerebello networks with consecutive behavioral modulation of cognitive processes impacting on daily life activities in healthy seniors and MCI patients. We will study the effect of NIBS techniques using transcranial magnetic and electrical stimuli, specifically a transcranial alternating current stimulation and a transcranial magnetic stimulation. Besides the behavioral effects, we will apply multimodal systems neuroscience approaches by means of neuroimaging (structural and functional MRI; s/fMRI) and electrophysiological (EEG, TMS) methods to determine the underlying network mechanisms and patterns of intrinsic connectivity changes. As there is significant spatial heterogeneity in fronto-parietal peak activity in healthy seniors and patients, stimulation targets will be individually defined based on fMRI. By leveraging the mechanistic aspects derived from individualized multifocal stimulation, we expect to better understand the mechanisms through which NIBS techniques act on the brain and improve cognitive functions. We will also test and quantify within a virtual reality (VR) task how well the intervention-driven cognitive improvement translates into daily life.