Reply to Del Giudice et al., Chekroud et al., and Rosenblatt: Do brains of females and males belong to two distinct populations?

  title={Reply to Del Giudice et al., Chekroud et al., and Rosenblatt: Do brains of females and males belong to two distinct populations?},
  author={Daphna Joel and Ariel Persico and J{\"u}rgen H{\"a}nggi and Jared Pool and Zohar Berman},
  journal={Proceedings of the National Academy of Sciences},
  pages={E1969 - E1970}
We are glad that our paper (1) raised discussions on the relations between sex and the brain and on our new methodological approach. Clearly, sex affects the brain, as evidenced in differences between brains from females and brains from males in both macroscopic and microscopic features. However, the fact that sex affects the brain does not necessarily entail that there are two distinct types of brains, “male brains” and “female brains,” as there are two distinct types of genitalia (2⇓–4… 

Analyzing brain data by sex: Are we asking the right question?

A mixture analysis of MRI-derived measures of grey and white matter revealed that 282 brain measures were better described by the hypothesis that women and men sample from the same two phenotypes, and that, for the most part, they do so with quite similar probabilities.

Beyond the binary: Rethinking sex and the brain

  • D. Joel
  • Psychology, Biology
    Neuroscience & Biobehavioral Reviews
  • 2021

Testing the masculinization hypothesis in a sample of 23,935 human brains

Results do not support the masculinization hypothesis but are consistent with the mosaic hypothesis as well as with other lines of evidence showing that the brain architectures typical of women are also typical of men, and vice versa, and that sex category explains a very small part of the variability in human brain structure.

Sex on the brain: Are gender‐dependent structural and functional differences associated with behavior?

  • A. Grabowska
  • Psychology, Biology
    Journal of neuroscience research
  • 2017
It is argued that some sex differences in the brain may serve to prevent (in the case where they are maladaptive), rather than to produce, differences at the behavioral/skill level.

Sex and gender affect the social brain: Beyond simplicity

  • M. A. Pavlova
  • Psychology, Biology
    Journal of neuroscience research
  • 2017
Clarification of how neurobiological sex and sociocultural gender affect the social brain would provide novel insights into understanding gender‐specific vulnerability to neuropsychiatric disorders.

Sex differences and the neurobiology of affective disorders

This article attempts to provide a framework for thinking about how sex and reproductive hormones (particularly estradiol as an example) might contribute to affective illness, and suggests several models that might explain a sex-dependent differential regulation of affect and susceptibility to Affective illness.

Analysis of Human Brain Structure Reveals that the Brain “Types” Typical of Males Are Also Typical of Females, and Vice Versa

The present findings demonstrate that sex category, whether one is female or male, is not a major predictor of the variability of human brain structure, and the brain types typical of females are also typical of males, and vice versa, and large sex differences are found only in the prevalence of some rare brain types.

Gender/Sex, Sexual Orientation, and Identity Are in the Body: How Did They Get There?

This review of theoretical and empirical approaches to the development of gender/sex and sexual orientation (SO) looks at both identities as deeply embodied, and considers how thinking about embodied cognition helps to address intersubjectivity and the emergence of subjective identity.

Untangling the Gordian Knot of Human Sexuality

It is now evident that humans cannot be characterized as member of 1 of 2 clearly defined units: male or female, and individuals exist on a continuum: those who do not conform unequivocally to the dyadic view of human sex in terms of anatomy, gender identity, and/or sexual behavior should be characterize as having variations in rather than disorders of sexual development.



Male or Female? Brains are Intersex

  • D. Joel
  • Psychology, Biology
    Front. Integr. Neurosci.
  • 2011
It is argued that human brains are composed of an ever-changing heterogeneous mosaic of “male’ and “female” brain characteristics that cannot be aligned on a continuum between a “ male brain” and a ”female brain.

Joel et al.'s method systematically fails to detect large, consistent sex differences

It is argued that claim i is based on faulty methodology, and claim ii is misleading if extended to overall sex differences in brain structure.

Sex beyond the genitalia: The human brain mosaic

This study demonstrates that, although there are sex/gender differences in the brain, human brains do not belong to one of two distinct categories: male brain/female brain and most brains are comprised of unique “mosaics” of features.

Patterns in the human brain mosaic discriminate males from females

The authors convincingly establish that there is little evidence for this strict sexually dimorphic view of human brains, counter to the popular lay conception of a “male” and “female” brain.

Beyond sex differences: new approaches for thinking about variation in brain structure and function

An approach to thinking about variation in brain structure and function that pulls us outside the sex differences formulation is offered, arguing that the existence of differences between the brains of males and females does not unravel the relations between sex and the brain nor is it sufficient to characterize a population of brains.

Genetic-gonadal-genitals sex (3G-sex) and the misconception of brain and gender, or, why 3G-males and 3G-females have intersex brain and intersex gender

  • D. Joel
  • Biology, Psychology
    Biology of Sex Differences
  • 2012
The categorization of individuals as “male” or “female” is based on chromosome complement and gonadal and genital phenotype, but although only ~1% percent of humans are 3G-“intersex”, when it comes to brain and gender, the authors all have an intersex brain (a mosaic of “ male” and “ female” brain characteristics).

Brain size, sex, and the aging brain

It is revealed that brain size is more important than Sex in explaining interindividual differences in compartmental volumes and when statistically controlling for brain size Sex differences and Sex × Age interactions practically disappear.

Multivariate revisit to “sex beyond the genitalia”

It is found that no single variable can separate human males from females, in contrast to genitalia-related data, which easily separate genders.

How sexually dimorphic are we? Review and synthesis

It is concluded that this frequency of deviation from the ideal male or female may be as high as 2% of live births and the frequency of individuals receiving “corrective” genital surgery probably runs between 1 and 2 per 1,000 live births.

The hypothesis of neuronal interconnectivity as a function of brain size—a general organization principle of the human connectome

The hypothesis of neuronal interconnectivity as a function of brain size might account for shorter and more symmetrical interhemispheric transfer times in women and for empirical evidence that visual and auditory processing are stronger lateralized in men is investigated.