# Computational reconstruction of evolutionary selection in human brain networks

## TL;DR

This paper introduces a new method to study how human brain networks evolved, linking genetic data with brain imaging to uncover evolutionary patterns in social and cognitive traits.

## Contribution

The novel contribution is an integrated workflow combining evolutionary genetics and fMRI data using a biclustering algorithm to explore brain evolution.

## Key findings

- Evolutionary selection peaks were found in brain networks related to social interaction and theory of mind across hominid ancestry.
- The identified traits involve multiple cell types, including excitatory and inhibitory neurons, and non-neuronal cells.
- Gene Ontology terms linked to these traits are enriched for synaptic organization and neuronal morphology.

## Abstract

The accumulation of genomic and brain data opens new opportunities for resource friendly, data driven brain exploration. A key challenge is to develop versatile and accessible strategies that integrate and mine multimodal datasets for novel neuroscientific insights. Here, we optimized an integrated workflow for mapping multigenic evolutionary traits in the human brain across cognitive, cellular, and molecular levels.

At the input stage, the workflow fuses an evolutionary genetic dataset with searchable synthetic functional magnetic resonance imaging (fMRI) databases that are pre clustered into concise psychological domains for improved interpretability. At its core, a Genetic Algorithm for Generalized Biclustering (GABi) mines gene sets under evolutionary selection that also show high expression correlation with fMRI networks.

Applying this workflow, we identified evolutionary patterns spanning cognitive traits, brain cell types, and molecular mechanisms. Focusing on socio affective traits, the algorithm highlighted peaks in adaptive selection in networks for social interaction (language) and social concepts (theory of mind) across hominid, early hominin, and anatomically modern human (AMH) ancestry. These traits emerge from a broad spectrum of excitatory (glutamatergic) and inhibitory (GABAergic) neuronal, as well as non neuronal, cell types. The associated Gene Ontology (GO) terms were enriched for cell signaling, synaptic organization, and neuronal morphology.

Together, these findings demonstrate an integrated workflow for molecular to systems level exploration of the brain and provide new perspectives on the evolutionary history of human socio affective functions. This approach can be adapted to screen for functional traits in the context of mental disorders or applied to the brains of other phylogenies in a similar manner.