Form and Function: The Brain

Brain Connectivity Predicts Function Across the Entire Human Brain

New research from Ohio State University suggests that patterns of connectivity between brain regions can reliably predict their specialized functions, offering a broad perspective on how the brain organizes cognition. This study, conducted by scientists at The Ohio State University, extends previous findings by examining the link across 33 cognitive processes, from sensory perception to executive decision-making.

Unraveling the Brain's Organizational Principle

For decades, neuroscientists have hypothesized that a region's function stems from its connections to other parts of the brain, much like how roads define a city's layout. Past studies demonstrated this for specific areas, such as those involved in vision or social behavior. However, evidence was limited to isolated functions.

This new work provides encouraging results by testing the idea across the whole brain. "We found evidence suggesting that connectivity is a fundamental organizational principle governing brain function, which has implications for understanding what happens when things go wrong in the brain," said Kelly Hiersche, lead author and doctoral student in psychology at The Ohio State University.

Results indicated a consistent correlation, supporting the notion that connectivity acts as a "fingerprint" for each region. "Just like how everyone's fingerprint is unique, we find that different brain regions have uniquely identifying connectivity fingerprints based on what mental function they perform," explained co-author Zeynep Saygin, associate professor of psychology at Ohio State.

Methodology: Combining Large-Scale Data and Computational Models

The researchers analyzed data from the Human Connectome Project, which scanned the brains of 1,018 individuals using functional magnetic resonance imaging (fMRI) to map resting-state connectivity—the patterns of synchronized activity between regions when the brain is at rest.

They paired this with NeuroQuery, an online meta-analysis tool that generates brain activation maps for cognitive terms based on thousands of published studies. This allowed them to model activation for 33 processes, including speech, memory retrieval, and face perception.

Using ridge regression—a statistical method that fits data while preventing overfitting—the team built models linking connectivity to predicted activation. These models were tested across brain lobes and hemispheres, with permutations to confirm robustness.

Key Findings: Strong Ties in Higher-Order Skills

The study revealed robust correlations between connectivity and function throughout the brain. Model fits were high overall, with medians ranging from 0.83 in parietal regions to 0.95 in cingulate areas.

Notably, the tightest links appeared in domain-general skills like executive function and memory, which outperformed sensory and social domains. "These higher-level skills take many years to develop in people, much longer than sensory or social skills," Hiersche noted. "It may be that as you continually use these regions of the brain for them to develop, it results in this very tight link between connectivity and function for these higher-order skills."

Lateralized functions, such as language (typically stronger in the left hemisphere), showed better fits in their dominant side. "Our findings help us understand the connectivity pattern that makes a language area unique, for example, and what makes it different from adjacent areas in the brain," said senior author David Osher, assistant professor of psychology at Ohio State.

"It supports a broadly held hypothesis among neuroscientists, that brain connectivity determines brain function, but this has not been explicitly shown until now, and not across such a large breadth of cognitive domains," Osher added.

Implications for Health and Future Research

This comprehensive view establishes a baseline for normal brain organization in young adults. "A major contribution of this study is that, because of the bird’s eye view of the brain, it can give scientists a baseline of how normal brains work in young adults," Hiersche said. This could aid in studying deviations in conditions like neurodegenerative diseases or developmental disorders.

"Knowing that connectivity is a general organizational principle of brain function across the entire brain provides a foundation for future work in this area" - Kelly Hiersche