User:Neuromath99/sandbox

Brain development

I am interested in neuroscience and gender studies; how our brains dictate who we are and who we become. In the same vein, I am interesting in child gender and sexuality development in terms of brain maturation and chemistry.

Women in the military, Gender Inequality in China, Neuroscience in Sexuality, Women in Nazi Germany, Reich Bride Schools

For Neuroscience of sex differences: brain diseases and sex differences

Stress and Gender from "Large-scale network balances in the transition from adaptive to maladaptive stress responses" by Homberg, Kozicz, and Fernandez

• Women's prefrontal cortexes and amgydalas are more responsive to stress than men's, however men tend to have a stronger hypothalamic response to stress compared to women. In terms of stress-prone diseases, women are more likely to suffer from post-traumatic stress disorder and clinical depression than men and girls who are more likely to perceive stressful situations as dangerous or threatening have a more active amygdala compared to boys.

Studies in humans have shown no difference between the sexes in the activation of the HPA-axis after physical exercise.

HPA axis- complex set of interactions between the hypothalamus and the pituitary glands and the adrenal glands that are at the top of each kidney.

Sex and Gender Affect the Social Brain: Beyond Simplicity by Marina A. Pavlova The idea that the human brain is intersex and does not belong to two specific genders has been ventured by the scientific community.

• the brain is not only female or male, and there are many common structures.
• The male brain is exposed to a completely different hormonal environment than the female brain starting in utero.
• sex differences in a specific behavior are often not predictable by the existence or lack of sex differences under other environmental conditions
• Experimental manipulation of gender-related stereotypic information in laboratory settings leads to fluctuations in behavior and corresponding brain activity
• in a study of gender stereotypes it was found that females tended to be more strongly affected by implicit compared with explicit negative information, whereas in males this relationship was opposite.
• positive stereotypes create efficient task-specific neural processes, whereas negative stereotypes elicit activity in areas involved in processing of negative emotions.
• Interaction between dissociated gender and sex may result in structural and functional alterations (or lack thereof) in the brain of transsexual

individuals, particularly during transition from the biological sex to the actual gender identity

• Sex-related differences in the brain do not always parallel behavior. Several types of interrelations between behavior

and underlying brain mechanisms with respect to sex differences may occur.

• Gender-related differences both in overt behavioral and in brain responses are detectable either at the behavioral level or in

brain activation.

Major Contribution

The terms sex and gender are often incorrectly used interchangeably in academic institutions and popular media. Sex is determined by biology while gender identity is primarily determined by psychological, social, and cultural influences.

A combination of numerous factors influence the many different dimensions of gender identity. Two of the models that have been developed to explain the differences in gender identity are the polygenic threshold and the culture-behavior-brain (CBB) loop model. The polygenic threshold model states that many genes contribute to complex traits. In the context of studying gender identity, it implies that no single set of genetic variants can possibly account for the differences in gender identity.Studies have shown that hundreds of thousands of genes contribute to variance in gender identity. These genes have only been linked to gender identity and have not been proven to directly create observable differences in gender identity traits. The polygenic threshold model also includes the idea that the human population exists in a spectrum of gender identities despite the fact that there may be decisive divisions of specific phenotypes in individuals.

Studies into the biological differences in transgender brains have resulted in contradictory conclusions that cannot account for the masculinization or feminization of the brain. Some studies have found differences in transgender brains in prenatal exposure to sexual hormones and genetic factors which point to distinct phenotypes in the brain for transgender men and women. However, other studies -especially those focusing on sexual chromosome deviations- have found no biological differences between transgender and cisgender brains. Studies on sexual hormone related genes have not obtained reliable results because they have not had a large enough population of transgender subjects and contained multiple testing errors. For these reasons, no clear and distinct genetic relationship with transexualism can be asserted until further testing is completed. This lack of adequate research creates the question of the origins of the differences in transsexual brains. Some experts still believe that there is an inherent difference in the brains of transsexuals from birth, while others theorize that the variance arises from culture and the behaviors and lifestyles that come with it.. Some researchers postulate that transsexualism is the result of a divergence between the sexual brain and genitals caused by androgens or genetic differences during fetal development. Those that believe that differences in transgender and cisgender brains are not present from birth cite that human's brains are changed by behavior, thought processes, and the social world. There is a continuous interaction between genes, the brain, and the environment. The thought processes of the brain and the environment of the individual can change neural structure as well as what genes are expressed and how they are expressed.

The nervous system has a great amount of plasticity. The structure and functionality of the brain changes as a result of accepting certain beliefs and performing certain behaviors. The adapted brain then directs behaviors fitting specific cultural expectations and sociocultural environments. After the brain has changed to match certain expectations, it can revert back to its initial conditions based on biological sex.

Although sex and gender are two distinct topics, research on the neuroscience of sex and gender are interwoven and many scientists do not accurately distinguish between the two. In order for research to advance and allow meaningful conclusions to be drawn without the presence of lurking variables, the two concepts need to be untangled from each other.

Annotated Bibliography for work on Neuroscience of Sex Differences

1. "Adult Development and Quality of Life of Transgender and Gender Nonconforming People"

Main Claims:

• There are distinct phenotypes of the brain for transgender men and women.
• Transgender men brains' phenotype shows a mixture of feminine and masculine traits.
• Transgender women brains' consist of feminine and masculine traits.
• Hypothesized that changes in transgender brains are due to androgen suppression or exogenous testosterone.

How it can fit into article: Transgender individuals show the differences in gender in single individuals that show differences from both sexes in brain anatomy.

Author Walter Bockting is a professor of Medical Psychology at Colombia University.

Bockting, Walter, et al. “Adult Development and Quality of Life of Transgender and Gender Nonconforming People.” Current Opinion Endocrinol Diabetes Obesity, 23 Apr. 2016, pp. 188–197. Science.gov, doi:10.1097/MED.0000000000000232.

Bockting, W., Coleman, E., Deutsch, M. B., Guillamon, A., Meyer, I., Meyer, W., . . . Ettner, R. (2016). Adult development and quality of life of transgender and gender nonconforming people. Current Opinion in Endocrinology & Diabetes and Obesity, 23(2), 188-197. doi:10.1097/med.0000000000000232

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4809047/

2. "Gender Development and the Human Brain"

Main Claims:

• Prenatal testosterone plays a role in sex differences and sexual orientation.
• Gender is multidimensional.
• Few sex differences in the brain have been linked to behavior.

How it can fit in the article: It says that gender is not based one one singular factor and many things must be taken into account. This slightly contradicts the articles citing direct impacts of certain sex differences in the brain to gendered behavior.

Author Melissa Hines is a professor in the psychology department at Cambridge University.

Hines, Melissa. “Gender Development and the Human Brain.” Annual Review of Neuroscience, vol. 34, 2011, pp. 69–88. Web of Science, doi:10.1146/annurev-neuro-061010-113654.

Hines, M. (2011). Gender Development and the Human Brain. Annual Review of Neuroscience, 34, 69-88. doi:10.1146/annurev-neuro-061010-113654

https://www-annualreviews-org.echo.louisville.edu/doi/10.1146/annurev-neuro-061010-113654

3. "New Directions in the Study of Gender Similarities and Differences"

Main Claims:

• The brain's plasticity allows it to adapt to new environments and experiences.
• Different regions of the brain are activated differently in males and females and others are activated by the same triggers.

How it can be used in the article: Brain plasticity is not mentioned very thoroughly, and not at all in the context of gender. It is a good contrast to the rest of the article which portrays brain functions as concrete between the different sexes.

Author Janet Shibley Hyde is a professor in psychology and women's studies at the University of Wisconsin-Madison.

Hyde, Janet Shibley. “New Directions in the Study of Gender Similarities and Differences.” Current Directions in Psychological Science, vol. 16, no. 5, 2007, pp. 259–263., doi:10.1111/j.1467-8721.2007.00516.x.

Hyde, J. S. (2007). New Directions in the Study of Gender Similarities and Differences. Current Directions in Psychological Science, 16(5), 259-263. doi:10.1111/j.1467-8721.2007.00516.x

https://s3.us-east-1.amazonaws.com/learn-us-east-1-prod-fleet01-xythos/5b5739b6d55fd/5721663?response-content-disposition=inline%3B%20filename%2A%3DUTF-8%27%27New%2520directions.pdf&response-content-type=application%2Fpdf&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20181019T035742Z&X-Amz-SignedHeaders=host&X-Amz-Expires=21600&X-Amz-Credential=AKIAIBGJ7RCS23L3LEJQ%2F20181019%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=066df7100d9ba576e7dcd38939541be1f4bb26a9d97dd2ad67f98bea30794647

4. "Transsexualism: A Different Viewpoint to Brain Change"

Main Claims:

• CBB loop model to explain gender- it originates at the individual level and is spread to the population level from social interactions.
• The brain can adapt itself to new culture. The can go back to the way it was originally.

How it fits into the article: It ties into the article by Shibley Hyde in the plasticity of the brain and it's ability to adapt. It will offer the same purpose as the Shibley Hyde article as well.

The authors are associated with and published this article on behalf of the University of Tehran located in Iran.

Mohammadi, Mohammad Reza, and Ali Khaleghi. “Transsexualism: A Different Viewpoint to Brain Changes.” Clinical Psychopharmacology and Neuroscience, vol. 16, no. 2, 2018, pp. 136–143., doi:10.9758/cpn.2018.16.2.136.

Mohammadi, M. R., & Khaleghi, A. (2018). Transsexualism: A Different Viewpoint to Brain Changes. Clinical Psychopharmacology and Neuroscience, 16(2), 136-143. doi:10.9758/cpn.2018.16.2.136

https://www-ncbi-nlm-nih-gov.echo.louisville.edu/pmc/?cmd=Search&term=1738-1088%5Bjour%5D+AND+16%5Bvolume%5D+AND+136%5Bpage%5D+AND+2018%5Bpdat%5D&otool=kyuloulib

5. "Sex and Gender Affect the Social Brain: Beyond Simplicity"

Main Claims:

• Research historically has oversimplified sex and gender or overlooked it entirely.
• In order to advance research in the neuroscience of sex and gender differences, the two concepts need to be unraveled from each other and regarded as the complex and multi-dimensional issues that they are.

How it fits into the article: It calls out the need to unravel the interlacing of gender and sex in neuroscience research, because they are two separate concepts. The article itself is evidence of the tie between the two concepts that people perceive as the same, but in reality aren't the same.

Author Marina Pavlova is a researcher in the department of Biomedical Magnetic Resonance at the University of Tuebingen.

Pavlova, Marina A. “Sex and Gender Affect the Social Brain: Beyond Simplicity.” Journal of Neuroscience Research, vol. 95, no. 1-2, 2016, pp. 235–250., doi:10.1002/jnr.23871.

Pavlova, M. A. (2016). Sex and gender affect the social brain: Beyond simplicity. Journal of Neuroscience Research, 95(1-2), 235-250. doi:10.1002/jnr.23871

https://onlinelibrary-wiley-com.echo.louisville.edu/doi/full/10.1002/jnr.23871

6. "The Biological Contributions to Gender Identity and Gender Diversity: Bringing Data to the Table"

Main Claims:

• The polygenic threshold model as an explanation for the genetics involved in determining gender.
• There are major genetic factors to identifying as cisgender or transgender; while environmental factors play smaller roles.

As of 2014, Tinca Polderman is an assistant professor at the Center of Neurogenomics and Cognitive Research in the Department of Complex Trait Genetics at Vrije Universiteit Amsterdam.

Polderman, Tinca J. C., et al. “The Biological Contributions to Gender Identity and Gender Diversity: Bringing Data to the Table.” Behavior Genetics, vol. 48, no. 2, 2018, pp. 95–108. Web of Science, doi:10.1007/s10519-018-9889-z.

Polderman, T. J., Kreukels, B. P., Irwig, M. S., Beach, L., Chan, Y., Derks, E. M., . . . Davis, L. K. (2018). The Biological Contributions to Gender Identity and Gender Diversity: Bringing Data to the Table. Behavior Genetics, 48(2), 95-108. doi:10.1007/s10519-018-9889-z

https://link-springer-com.echo.louisville.edu/content/pdf/10.1007%2Fs10519-018-9889-z.pdf

7. Delusions of Gender: How Our Minds, Society, and Neurosexism Create Difference

Main Claims:

• Neuroscientists have a responsibility to take into account how their results can be extrapolated and misappropriated.
• Some scientist link differences in brain structures to behavior, but that is a fallacy when there are so many things that contribute to behavior.
• Brain "facts" tend to be taken as concrete without many questions.
• "Our brains are changed by our behavior, our thinking, our social world. The new neuroconstructive perspective of brain development emphasizes the sheer exhilarating tangle of continuous interaction among genes, brain, and environment... Our environment, our behavior, even our thinking can all change what genes are expressed. And thinking, learning, sensing can all change neural structure directly." (Fine, 177).
• "...speculation becomes elevated to the status of fact... Once in the public domain these supposed facts about male and female brains become part of the culture... they reinforce and legitimate the gender stereotypes that interact with our minds, helping to create the very gender inequalities that the neuroscientific claims seek to explain" (186).

How it fits into the article: It addresses the dangers in extrapolating differences in brain structure to observable and non-observable behaviors. Many of the sources in the article are primary and are very close to crossing the line of extrapolation. It also supports the claims of other authors that gender is composed of more than just genetics and biology; environment plays a large role as well.

Author Cordelia Fine is a philosopher, psychologist and writer; as well as a full professor of History and Philosophy of Science at The University of Melbourne.

Fine, Cordelia. Delusions of Gender: How Our Minds, Society, and Neurosexism Create Difference. W.W. Norton, 2011.

Fine, C. (2011). Delusions of gender: How our minds, society, and neurosexism create difference. New York: W.W. Norton.

8. "Gender and Creativity: An Overview of Psychological and Neuroscientific Literature"

Main Claims:

• "...No study has systematically investigated what proportion of the gender-dependent variance in creative achievement is attributable to biological or sociocultural factors. This is unsurprising given the sheer complexity of the challenge involved in undertaking such a research venture. Scientific investigations of gender differences in cognition and behavior have not been conducted thus far with a view to determine the causes of potential variability."

How it fits into the article: It substantiates claims by other articles that there has not been enough scientific research that is able to separate the biological factors from the societal ones. Only after these factors are isolated in studies can an affirmative line be drawn between sex and gender.

Author Anna Abraham is a professor of psychology in the School of Social Sciences at Leeds Beckett University.

Abraham, Anna. “Gender and Creativity: an Overview of Psychological and Neuroscientific Literature.” Brain Imaging and Behavior, vol. 10, no. 2, Sept. 2015, pp. 609–618., doi:10.1007/s11682-015-9410-8.

Abraham, A. (2015). Gender and creativity: An Overview of Psychological and Neuroscientific Literature. Brain Imaging and Behavior, 10(2), 609-618. doi:10.1007/s11682-015-9410-8

https://link-springer-com.echo.louisville.edu/content/pdf/10.1007%2Fs11682-015-9410-8.pdf