Ewha Med J.  2024 Apr;47(2):e16. 10.12771/emj.2024.e16.

Current status and significance of research on sex differences in neuroscience: a narrative review and bibliometric analysis

• Kim H
• Lee H

• KMID: 2556305
• DOI: http://doi.org/10.12771/emj.2024.e16

Abstract

This review aims to highlight the importance of research on structural, functional, molecular-biological, and disease-specific sex differences in the brain, and to examine current bibliometric indicators related to research on sex differences. The Web of Science Core Collection was searched for related articles from 2010 to 2023. Structural and functional brain differences according to sex, including variations in communication patterns between hemispheres, may play a role in mental disorders. Sex differences in neurotransmitters such as serotonin, dopamine, and γ-aminobutyric acid contribute to disparities in mental health, addiction, and neurodevelopmental conditions. Neurodevelopmental disorders such as autism spectrum disorder and schizophrenia exhibit sex-based differences in prevalence, symptoms, brain changes, and neurotransmitter disruptions under hormonal influence. There is a growing body of research on depression, adolescence, the hippocampus, the amygdala, and cognition, highlighting the importance of considering sex/gender factors. Recent studies on sex differences in brain diseases have identified variations in brain structure, function, and neurophysiological substances, as well as in hormones and genes between the sexes. The incidence of psychiatric disorders such as autism spectrum disorder, depression, anxiety, and Alzheimer's disease is increasingly being linked to sex differences, and the need for research into the mechanisms underlying these differences is gaining recognition. However, there remains a significant gap in sex-specific neuroscience research related to the diagnosis, treatment, prevention, and management of these conditions. Advancing inclusive research will require comprehensive training, a consensus on methodology, diverse perspectives through collaborative frameworks, governmental/institutional support, and dedicated funding to create suitable research environments and implementation strategies.

Keyword

Neuroscience research, Bibliometric analysis; Mental health; Psychiatry; Sex characteristics

Figure

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  Fig. 1. Several neurological disorders that exhibit sex differences. Male bias (grey), female bias (yellow). ADHD, attention-deficit/hyperactivity disorder.

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  Fig. 2. Trends in sex/gender-specific papers (number of publications) in neuroscience (red), psychiatry (pink), behavioral sciences (green), cell biology (blue), and biology (purple).

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  Fig. 3. Keyword co-occurrence networks in brain research. The colors of circles are used to identify the clusters resulting from analyses of the relationships provided by the VOS Viewer software (red: disorders, blue: complex, green: method, purple: addiction, cluster size: frequency).

Reference

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