Connectivity and function are coupled across cognitive domains throughout the brain

Abstract

Decades of neuroimaging have revealed that the functional organization of the brain is roughly consistent across individuals and at rest it is resembles group-level task-evoked networks. A fundamental assumption in the field is that the functional specialization of a brain region arises from its connections to the rest of the brain, but limitations in the amount of data that can be feasibly collected in a single individual, leaves open the question: Is the association between task activation and connectivity consistent across the brain and many cognitive tasks? To answer this question, we fit ridge regressions models to activation maps from 33 cognitive domains (generated with NeuroQuery) using resting-state functional connectivity data from the Human Connectome Project as the predictor. We examine how well functional connectivity fits activation and find that all regions and all cognitive domains have a very robust relationship between brain activity and connectivity. The tightest relationship exists for higher-order, domain-general cognitive functions. These results support the claim that connectivity is a general organizational principle of brain function by comprehensively testing this relationship in a large sample of individuals for a broad range of cognitive domains and provide a reference for future studies engaging in individualized predictive models.

Keywords: cognition; connectivity fingerprinting; fMRI; functional connectivity; whole brain.

Figure 1:

A. Expected activation maps (from NeuroQuery, left) and connectivity-based fitted activation (right) for two sample cognitive domains. B. Large colored bars show median fit (with standard error bars) for each domain across regions. Subset black bars show the 99^th percentile performance of the permuted models for each domain. Sensory is in purple, somatosensory is in blue, language is in green, social is in blue-green, decision making is in red, memory is in orange, and executive functioning is in yellow.

Figure 2.

Large colored bars show the median fit (with standard error bars) for each region across domains. Subset black bars show the 99^th percentile performance of the permuted models. Occipital lobe in purple, temporal in green, parietal in dark blue, frontal in red, cingulate in yellow and subcortical in blue.

Figure 3:

Results of one-way ANOVA and test of lateralized functions. A. Main effect of category with mean model fit with standard error bars. *p<0.05, surviving Bonferroni-Holm multiple comparison corrections for 21 comparisons. B. Hemispheric differences for lateralized functions. Mean model fit with standard error bars. *p<0.05, Bonferroni-Holm corrected for 6 comparisons.

Figure 4:

Diagram outlining the model procedures for one domain and one region. This process was repeated for all 33 domains and 82 regions.