Fig. 1

Reproducing individual neural activity during task execution at different levels of cognitive decline (A): EEG recordings were collected during task execution from participants in several stages of cognitive decline. B The BNM simulates EEG activity during virtual task execution (see Methods, “Virtual version of cognitive task” paragraph). C Cognitive task is modelled by a virtual stimulus propagating along the ventral stream of visual information. D, E Both experimental (D) and simulated (E) EEGs were pre-processed to extract ERP components. F Relevant EEG features such as encoding functional connectivity and N1 waveforms were computed from extracted ERP in both experimental and simulated signals. G Experimental and simulated ERPs are compared to tune the parameters of the BNM for each participant, using a gradient descent algorithm. The algorithm determines the combination of model parameters that minimizes difference between experimental and simulated signals. The procedure is repeated for each participant. H The determination of personalized parameter combinations allowed us to reproduce individual EEG signals. Signals were reproduced across several EEG channel groups, specifically occipital channels, prominent in encoding processes (top) and central channels, prominent in decision processes (bottom). I Personalized parameters also allowed to reconstruct a BNM for each participant, investigating structural configurations associated with each cognitive condition. Abbreviations: \(cp\): connectivity parameter (parameter of connectivity degeneration); EEG: electroencephalography; ERP: Event-Related Potential; exp: experimental, IT: Inferior Temporal Cortex; \(lp\): local parameter (parameter of synaptic degeneration); sim: simulated; V1: Primary Visual Cortex, V2: Secondary Visual Cortex, V4: Visual Area V4