PT  - JOURNAL ARTICLE
AU  - Arian Ashourvan
AU  - Sérgio Pequito
AU  - Maxwell Bertolero
AU  - Jason Z. Kim
AU  - Danielle S. Bassett
AU  - Brian Litt
TI  - External drivers of BOLD signal’s non-stationarity
AID  - 10.1101/2021.09.07.459325
DP  - 2021 Jan 01
TA  - bioRxiv
PG  - 2021.09.07.459325
4099  - http://biorxiv.org/content/early/2021/09/07/2021.09.07.459325.short
4100  - http://biorxiv.org/content/early/2021/09/07/2021.09.07.459325.full
AB  - A fundamental challenge in neuroscience is to uncover the principles governing how the brain interacts with the external environment. However, assumptions about external stimuli fundamentally constrain current computational models. We show in silico that unknown external stimulation can produce error in the estimated linear time-invariant dynamical system. To address these limitations, we propose an approach to retrieve the external (unknown) input parameters and demonstrate that the estimated system parameters during external input quiescence uncover spatiotemporal profiles of external inputs over external stimulation periods more accurately. Finally, we unveil the expected (and unexpected) sensory and task-related extra-cortical input profiles using functional magnetic resonance imaging data acquired from 96 subjects (Human Connectome Project) during the resting-state and task scans. Together, we provide evidence that this embodied brain activity model offers information about the structure and dimensionality of the BOLD signal’s external drivers and shines light on likely external sources contributing to the BOLD signal’s non-stationarity.Competing Interest StatementThe authors have declared no competing interest.