Recruiting the right hemisphere: Sex differences in inter-hemispheric communication during semantic verbal fluency

Area of Science:

• Cognitive Neuroscience
• Neuroimaging
• Sex Differences Research

Background:

• Sex differences in cognitive functions are a subject of ongoing debate.
• Previous research suggests distinct processing strategies between sexes, potentially reflected in brain networks.
• The direct link between brain networks and cognitive strategies in sex differences remains largely speculative.

Purpose of the Study:

• To investigate for the first time the link between sex differences in brain activation patterns and cognitive processing strategies.
• To utilize a semantic verbal fluency task to explore these sex-based differences in neural recruitment.

Main Methods:

• A large sample of 35 men and 35 women underwent functional magnetic resonance imaging (fMRI) thrice.
• Participants completed a semantic verbal fluency task, allowing for the analysis of clustering and switching strategies.
• Analyses included brain activation patterns, lateralization indices, and connectivity analyses.

Main Results:

• Men showed significantly higher activation in brain networks associated with clustering strategies.
• Women demonstrated higher activation in brain networks linked to switching strategies.
• Men exhibited stronger right-hemisphere recruitment during clustering, while women showed stronger right-hemisphere recruitment during switching.

Conclusions:

• The study establishes a direct link between sex differences in brain activation and distinct cognitive processing strategies during verbal fluency.
• Findings suggest sex-specific recruitment of brain networks, particularly hemispheric lateralization, underlies differential strategy use.
• These results provide a neurobiological explanation for previously observed behavioral differences in performance and strategy selection between men and women.