27.08.2021 President Thomas Bach                                                                                                                         

Attention: Prof Dr Uğur Erdener Chairman, IOC Medical & Scientific Commission                           

International Olympic Committee (IOC)  

Maison Olympique                                                                                                
1007 Lausanne
Switzerland 1007 Lausanne
Tel: +41 21 621 6000, email: pressoffice@olympic.org, web site at www.ioc.org.

Dear Sir,

Brain Cognitive Functions Determine Human Athletic Performance   Not Testosterone Levels

The IOC in a statement titled “IOC Consensus Meeting on Sex Reassignment and Hyperandrogenism November 2015” detailed the Criteria for Transgender Guidelines. Which include that, those who transition from female to male are eligible to compete in the male category without restriction. Secondly, those who transition from male to female are eligible to compete in the female category under the following conditions: the athlete must demonstrate that her total testosterone level in serum has been below 10 nmol/L for at least 12 months prior to her first competition, and remain below 10 nmol/L throughout the period of desired eligibility to compete in the female category.

The committee acknowledged that these guidelines are a living document and will be subject to review in light of any scientific or medical developments. It was on the basis of these guidelines that the transgender weightlifter Laurel Hubbard got to compete at the Tokyo Olympics. The Olympics is just one of the major international events that allow Transgender eligibility criteria. This is unfortunate and totally anti-science. It should be obvious to any attentive observer that gender differences are not set by hormonal level differences alone.

As a leading international neuroscientist, I would like to draw your attention to five most important discoveries in gender differences in brain cognitive functions in the 21st Century.

1.     Men process tasks of general intelligence in the right hemisphere of the brain, while women process same in the left hemisphere of the brain. [Philip C. Njemanze. Cerebral lateralization and general intelligence: Gender differences in a transcranial Doppler study. Brain and Language, 92, 234-239. (2005). https://citeseerx.ist.psu.edu/viewdoc/download?doi=].

This work suggests that, the neural system for general intelligence in men and women are completely different and located on opposite sides of the brain. This profound discovery was validated using other neuroimaging methods by other leading American neuroscientists. The work by [Daniel Tranel, Hanna Damasio, Natalie L. Denburg, Antoine Bechara.

 Does gender play a role in functional asymmetry of ventromedial prefrontal cortex? Brain, 128, 2872 -2881, (2005). https://doi.org/10.1093/brain/awh643 ] using positron emission tomography (PET) studies confirmed the findings by Njemanze, 2005, and suggested that, men and women use different strategies to solve similar problems, men use holistic strategy linked to the right hemisphere, while women use analytic strategy linked to the left hemisphere. Furthermore, another group of American neuroscientists [Jung, R. E., Haier, R. J., Yeo, R. A., Rowland, L. M., Petropoulos, H., Levine, A. S., et al. Sex differences in N-acetylaspartate correlates of general intelligence: An 1H-MRS study of normal human brain.Neuroimage, 26, 965-972. (2005). https://www.researchgate.net/publication/7786353_Sex_differences_in_N-acetylaspartate_correlates_of_general_intelligence_An_1H-MRS_study_of_normal_human_brain ]

In this study, they determined that N-acetylaspartate (NAA), a metabolite found primarily within neurons, is related to intelligence as assessed by the Wechsler Adult Intelligence Scale-III.  In women, but not men, they found a strong association of intelligence with NAA in the left frontal and left occipito-parietal regions of the brain.

2.     Men process faces in the right hemisphere while women process same in the left hemisphere [Philip C. Njemanze. Cerebral lateralisation for facial processing: Gender-related cognitive styles determined using Fourier analysis of mean cerebral blood flow velocity in the middle cerebral arteries Laterality, 12 (1), 31-49, (2007)  https://www.researchgate.net/publication/6707712_Cerebral_lateralisation_for_facial_processing_Gender-related_cognitive_styles_determined_using_Fourier_analysis_of_mean_cerebral_blood_flow velocity_in_the_middle_cerebral_arteries ]

The results have been validated by studies used in a meta-analysis of 817 male (n = 414) and female (n = 403) healthy adults from Asia, Europe and America. The results demonstrated the presence of a sex difference in the way the two cerebral hemispheres process facial information in humans, with a marked right-sided asymmetry of the bioelectrical activity in males and a bilateral or left-sided activity in females. [Alice M. Proverbio. Sexual dimorphism in hemispheric processing of faces in humans: A meta-analysis of 817 cases. Social Cognitive and Affective Neuroscience, nsab043, 1–13. (2021). https://doi.org/10.1093/scan/nsab043 ].

3.     Men process colors in the right hemisphere while women process colors in the left hemisphere. More specifically, gender-related differences in color processing demonstrated a right hemisphere cognitive style for wavelength-differencing in men, and a left hemisphere cognitive style for frequency-differencing in women [Philip C. Njemanze   

Gender-related asymmetric brain vasomotor response to color stimulation: a functional transcranial Doppler spectroscopy study. Experimental & Translational Stroke Medicine, 2:21, (2010). https://etsmjournal.biomedcentral.com/articles/10.1186/2040-7378-2-21 ]. The 3D-color space for women was a mirror-image of that for men, and showed enhanced color constancy [Philip C. Njemanze. Gender-related differences in physiologic color space: a functional transcranial Doppler (fTCD) study, Experimental & Translational Stroke Medicine 3:1, (2011). http://www.etsmjournal.com/content/3/1/1 ].

4.     Our center in conjunction with Helmholtz-Zentrum Dresden- Rossendorf, Leipzig, Germany, undertook experiments using animal models to examine gender differences during color stimulation using PET/MRI.  The metabolic connectivity of the orbital and medial prefrontal cortex evoked by blue stimulation spread through a wide range of brain structures implicated in viscerosensory and visceromotor systems in the left intra-hemispheric regions in male, but in the right-to-left inter-hemispheric regions in female mice. Color functional ocular dominance plasticity was noted in the right eye in male mice but in the left eye in female mice [Njemanze PC, Kranz M, Amend M, Hauser J, Wehrl H, Brust P. (2017) Gender differences in cerebral metabolism for color processing in mice: A PET/MRI Study. PLoS ONE 12(7): e0179919, (2017). https://doi.org/10.1371/journal.pone.0179919  ].

Furthermore, it was uncovered that the neural networks for processing colors in male and female mice were different. In male mice, black-white (luminance) opponency occurred in the subcortical pathways in the dorsal stream in the left visual cortex, while color (chromatic) opponency involved the cortical pathways in the ventral stream in the left visual cortex.

In female mice, luminance processing occurred in the cortical pathways in the ventral stream in the right visual cortex. Conversely, chromatic opponency took place in the subcortical pathways in the dorsal stream in the right visual cortex. [Njemanze PC, Kranz M, Brust P. Fourier Analysis of Cerebral Metabolism of Glucose: Gender Differences in Mechanisms of Color Processing in the Ventral and Dorsal Streams in Mice. Forecasting 2019, 1, 135–156; https://doi.org/10.3390/forecast1010010  ]. Figure 1 summarizes the Human Brain Network for processing in men and women, respectively.

Visual pathways USED.jpg

Figure 1. The Light and Color Processing Pathways in Men and Women.

5.     Light has a dual nature as a wave and particle. Information is carried by light. Men process the light wave, while woman process the light particles called photons. In male mice, there was classical superposition of waves for processing of polarized and yellow lights, in the ventral stream of the left visual cortex.

Conversely, in female mice, polarized light particle evoked changes of quantum superposition in the subcortical region in the dorsal stream in the right visual cortex. Electron ‘tunneling’ occurred in the cytochrome oxidase blobs in the right visual cortex in female mice [Njemanze PC, Kranz M and Peter Brust. Gender Differences in Cerebral Metabolism Induced by Polarized Light in Mice Brain: A Quantum Coherence Model. International Journal of Nuclear Medicine & Radioactive Substances, 3(3): 000135, (2020), https://medwinpublishers.com/IJNMRS/Gender%20Differences%20in%20Cerebral%20Metabolism%20Induced%20by%20Polarized%20Light%20in%20Mice%20Brain%20A%20Quantum%20Coherence%20Model.pdf ].

In summary, men utilize the right brain for general intelligence, facial and color processing, while, women use the left brain for the same. In animals the opposite trend was observed. I postulated the “Theory of Everything in the Brain’ based on the dual nature of light as a wave and as a particle, with men seeing light as a wave and women seeing the light particle, to achieve gender complimentarity for perception of the world around us. Gender differences in the brain of men and women are diverse and natural (Latin: duae res diversae naturae) and cannot be altered by hormonal levels.

Neither can gender differences be legislated into gender sameness to achieve gender equality. It is regrettable that, some authorities at the IOC, US Congress and Council of Europe have chosen an unscientific approach purported as Gender Equality Rights, which has endangered Women’s Sports and is in breach of women’s rights.

The preferred approach is Gender Complimentarity, which takes into account, areas of comparative advantage for men and women respectively, of separate but equal importance. Women’s sports should be as high-profiled as men’s sports and free from contamination with biological men posing as ‘trans-athletes’. Sports are biophysical endeavor based on human bio-physiology and not psycho-social constructs. Empirical approaches to gender separation in sports achieved some of these goals but more work remains to be done. What we have demonstrated through advanced neuroscience research is that, there are real neurobiological gender differences that justify gender separation in sports. We hope that those concerned would take the corrective measures and put an end to the quest for a Genderless Society.

Yours sincerely,


Academician (Prof.) Dr Philip C. Njemanze MD (Hons). Chairman, International Institutes of Advanced Research and Training, Chidicon Medical Center, Owerri, Imo State, Nigeria.

Copies Sent To:

Copies sent to:

His Holiness Pope Francis

UN Secretary General

President of the United States of America

Speaker of the US Congress

President of the Council of Europe

President of the African Union

President of the Federal Republic of Nigeria

World Anti-Doping Agency (adams@wada-ama.org)

International Press and others.


Academician (Prof) Prince Dr Philip C. Njemanze MG (Hons) is a medical doctor and a leading international neuroscientist. Njemanze is a full Academician of the International Academy of Astronautics (IAA), the highest UNESCO body for Space Research. He was a former Principal Investigator of the National Aeronautic and Space Administration (NASA) in the international study of the Brain in Space (Neurolab) and Global Health Monitoring Program at NASA Ames Research Center, Moffett Field California, USA.


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