Why, where and how do top-down and bottom-up signals interact in the primate brain?

• DOI: 10.31234/osf.io/7mryq_v2
• Publication Date: 2025-05-13T17:44:06Z
• Authors: Yujie Hou; Julien Vezoli; Kenneth Knoblauch; Rainer Göbel; Martin Vinck; Henry Kennedy

Here we propose a roadmap for addressing hierarchical predictive coding theory (hPC) in the primate brain. hPC proposes that perception arises from integration of bottom-up (BU) pathways carrying sensory evidence with top-down (TD) priors and expectations. However, there is surprising little concerning location functional mechanisms underlying such BU-TD integration. This can be overcome by future parallel experiments humans non-human primates (NHPs). Molecular characterization NHP cortico-cortical BU TD projection cell types will allow tracing these circuits exerting causal control to explore visual paradigms behaving NHPs. Identical human subjects undergoing ultra-high field laminar fMRI scanning indicate homologous In human, long-distance expectations suggest claustrum might involved hPC. Recent connectomic transcriptomic characterisation cortical claustral loops enable similar approach pathways’ participation signals as used pathways.