# Dynamic brain lateralization patterns in Chinese naturalistic language comprehension and association with sex differences: a 7T functional magnetic resonance imaging study

## TL;DR

This study explores how the brain's left and right hemispheres work together during Chinese language processing and finds sex differences in how rational and emotional content is handled.

## Contribution

The study reveals dynamic brain lateralization states during Chinese language comprehension and links them to sex differences influenced by hormones.

## Key findings

- Two dynamic lateralization states were identified during Chinese language processing.
- Males showed a stronger tendency for left-lateralized rational content processing, while females favored right-lateralized emotional content.
- Genetic analysis suggests sex hormones influence these lateralization patterns.

## Abstract

Although language is traditionally regarded as unique to humans and predominantly left-lateralized in the brain, the dynamic interplay between cerebral hemispheres during language processing remains poorly understood.

Using 400 functional magnetic resonance imaging scans acquired with a 7T scanner under diverse narrative stimuli, this study examined whole-brain functional dynamic lateralization patterns during Chinese language processing and explored potential sex differences.

We identified two distinct dynamic lateralization states. While core language regions consistently showed left-lateralization, other brain regions displayed reversed lateralization. These two states—characterized by higher-level functional regions lateralizing either left or right—corresponded to the processing of rational and emotional content, respectively. Notably, males showed a stronger tendency toward the former state, whereas females inclined toward the latter, particularly during the processing of rational content. Genetic analyses further suggested that sex differences in these lateralization states may be influenced by sex hormones.

This study offers novel insights into the dynamic organization of cerebral lateralization during Chinese language processing.