The Physics Network is Distinct from the Multiple Demand System in the Human Brain

Abstract

Recent studies implicate regions of the human bilateral fronto-parietal cortices in intuitive physical reasoning--our ability to perceive, predict, and plan in the physical world. However, it remains unclear whether this "Physics Network" (PN) constitutes a distinct and domain-specific system, or whether instead it overlaps with the nearby domain-general multiple demand (MD) network. To answer this question, we scanned participants (N = 20) with fMRI in a pre-registered study and measured spatial overlap, response profile differences, and resting-state correlation between the PN and MD networks. We find that: (1) The PN and MD networks overlap only minimally within individual participants, (2) Each network exhibits distinct functional profiles across a broad array of tasks, and (3) Time courses of functional response are more correlated between subregions within the same network than subregions between networks. These findings indicate that the Physics Network is dissociable from the Multiple Demand system both spatially and functionally, supporting its distinct role in intuitive physical reasoning.