The hierarchical organization of the precuneus captured by functional gradients

Abstract

The precuneus shows considerable heterogeneity in multiple dimensions including anatomy, function, and involvement in brain disorders. Leveraging the state-of-the-art functional gradient approach, we aimed to investigate the hierarchical organization of the precuneus, which may hold promise for a unified understanding of precuneus heterogeneity. Resting-state functional MRI data from 793 healthy individuals were used to discover and validate functional gradients of the precuneus, which were calculated based on the voxel-wise precuneus-to-cerebrum functional connectivity patterns. Then, we further explored the potential relationships of the precuneus functional gradients with cortical morphology, intrinsic geometry, canonical functional networks, and behavioral domains. We found that the precuneus principal and secondary gradients showed dorsoanterior-ventral and ventroposterior-dorsal organizations, respectively. Concurrently, the principal gradient was associated with cortical morphology, and both the principal and secondary gradients showed geometric distance dependence. Importantly, precuneus functional subdivisions corresponding to canonical functional networks (behavioral domains) were distributed along both gradients in a hierarchical manner, i.e., from the sensorimotor network (somatic movement and sensation) at one extreme to the default mode network (abstract cognitive functions) at the other extreme for the principal gradient and from the visual network (vision) at one end to the dorsal attention network (top-down control of attention) at the other end for the secondary gradient. These findings suggest that the precuneus functional gradients may provide mechanistic insights into the multifaceted nature of precuneus heterogeneity.

Cognitive archaeology, and the psychological assessment of extinct minds

“…Besides the paleoneurological inferences on the evolution of these regions in our species, there is in fact no doubt that Homo sapiens , for example, displays a much larger precuneus than other primates (Bruner et al., 2017). The precuneus is crucial for many functions integrating brain, body, and environment (see Cavanna & Trimble, 2006; Jiang et al., 2023; Margulies et al., 2009) (Figure 2d,g). It is associated with a clear longitudinal gradient integrating body perception (anteriorly) with visual perception (posteriorly), providing the neural basis for visual imaging and body–space integration.…”