Born This Way?

Homosexuality, Science, and the Scriptures

J. Alan Branch

• Éditeur: Lexham Press
• Année: 2018
• ISBN:
  9781683591870
• Sujet: Teología y religión
• Sous-sujet: Sexualidad y género en la religión

Lady Gaga's song "Born This Way" has become an anthem for homosexual rights, asserting in a simplistic fashion that same-sex attraction is a trait much like hair or skin color. In Born This Way?, the author surveys the most common scientific arguments in favor of homosexuality and respond to pro-homosexual arguments. A review of the research will show that, while there are some genetic or biological factors that correlate with a higher incidence of same-sex attraction and homosexual behavior, as of yet there is no proof of genetic or biological causation for homosexuality.

Chapter 6

Heterosexual and Homosexual Brain Differences

Many Christians have experienced a family member who has “come out of the closet” and announced he or she is a homosexual. One such friend of mine was quite surprised when his older brother announced to the family he was embracing the gay lifestyle. Eventually, my friend’s brother claimed, “I have a male body, but I have a female brain. That’s why I’m attracted to men.” Apparently, his brother had encountered pro-homosexual arguments asserting homosexual men have a brain structure similar to heterosexual women. For my friend’s brother, being “born this way” meant he was born with a woman’s brain, was attracted to men, and thus was morally free to embrace the gay lifestyle.

But is this claim accurate? Are there substantial differences between the brains of heterosexuals and homosexuals? Do homosexual men have brains more like heterosexual women and do homosexual women have brains more like heterosexual men? In this chapter we will see that while there have been some intriguing findings regarding brain differences of heterosexuals and homosexuals, no definitive link has yet been discovered between a particular brain structure or pattern of organization which necessarily causes homosexuality. To grasp the issues related with these “gay brain” arguments, we will begin by summarizing gender-specific brain differences in animal research, then move to gender differences in the human brain, and conclude with a Christian evaluation of born-this-way arguments based on purported brain differences.

Gender Differences, Born-this-Way Arguments,
and Rodent Brains

Born-this-way arguments about sex-related brain differences find their origin in research on rodent brains.1 One of the most interesting discoveries occurred in 1978 when a team of neurobiologists led by Roger Gorski of UCLA identified differences between the hypothalamus in male and female rats. They observed a small cluster of cells (or a “nucleus”) in the hypothalamus that was five times larger in male rats than in female rats. The difference in this particular area was so pronounced, Gorski found he could determine the animal’s sex with near 100% accuracy using only the naked eye to examine their brains.2 This observable area of in rat brains was named the “sexually dimorphic3 nucleus of the preoptic area” (SDN-POA). While we now know humans do not have a SDN-POA like rats do, this type of research on rodent brains set the trajectory for the following decades concerning scientific inquiry into gender-specific differences in the human brain and corresponding research concerning brain structure and homosexuality.4 If the hypothalamus in rat brains was so very different, many researchers wondered if there were corresponding differences in the human hypothalamus which could explain sexual identity and desire.

At this point, some may wonder why research on rat brains is brought up in debates about homosexuality. From an evolutionary view, all mammals share a common ancestor. Dates for this common ancestor vary widely from between 65 to 200 million years ago, but the implication is rats and humans are long-lost relatives. Born-this-way advocates suspect parts of the hypothalamus in humans and rats are homologous, meaning they share the same evolutionary origins. Based on the premise that rats and humans share a common ancestor and combined with the fact the hypothalamus is connected with our sexual drive, scientific observations of rodent sexual behavior is considered informative for research into human sexual behavior.

Gender Differences in the Human Brain

Born-this-way arguments presume a substantial difference exists between male and female brains. But to what degree are male and female brains actually different? Trying to discover consensus about the exact gender differences in our brains can be confusing. Competing and contradictory assertions abound, but several claims are commonly accepted within the scientific community.5 The most consistently proven difference between male and female brains is that male brains are larger. Pro-homosexual authors Cohler and Galatzer-Levy go so far as to say, “During the past century, numerous researchers have tried to find anatomic factors differentiating the male and female brain. To date, only one reliable difference has been found — regardless of sexual orientation, men have slightly larger brains than women.”6 Another difference is that, as a general rule, male brains have a higher percentage of “white” matter — tissue composed of nerve fibers which connect the various components of the brain like a networking grid — while women have a higher percentage of “gray” matter — tissue containing neurons which are essential for thinking.7 Another common difference is that the amygdala is usually larger in males than females.8 Other claims about sex-related brain differences abound, but the ones mentioned here give a sufficient idea of the types that are generally accepted.

Many believe some of the proposed structural differences between male and female brains account for gender-specific abilities. It is widely held that girls are better at empathizing (the ability to respond to someone with an appropriate emotion), while boys are better at systemizing (the ability to understand how non-human systems work by analyzing them).9 Gender-specific differences are also central to burgeoning research on issues like autism in males and depression in females. Concerning sexual attraction, visual stimuli appear to play a significantly greater role in male sexual desire and behavior.10

In 1989, Allen and Gorski of UCLA made a new discovery relevant to gender differences in humans and identified four cell groups of interest in the preoptic area of the hypothalamus. Allen coined a new name for these cell groups: the “Interstitial Nuclei of the Anterior Hypothalamus” (INAH 1-4). Allen and Gorski said the INAH 2 was twice as large in men as in women and that INAH 3 was 2.8 times as large in men as in women.11 These very specific findings regarding INAH 3 soon became the focus of later studies concerning brain structure, homosexuality, and born-this-way arguments.

In recent decades, the conclusion was reached that human brains are somewhat sexually dimorphic, meaning the brains of males and females exist in two somewhat distinct forms. But the similarities between male and female brains far outweigh the differences. Men and women share the same structures and the various components serve the same functions in both genders. Men and women share equal intelligence. Many sex-specific differences have often been exaggerated by purveyors of pop psychology and the popular media. Differences in particular structures which have been identified are often differences in volume or shape. Nonetheless, as research on gender differences moved forward, some scientists began to speculate that homosexuals may have brain differences which separate them from heterosexuals. The claims and counter-claims regarding findings in this area have often been controversial with significant implications in political arguments for homosexual rights. We will now review particular born-this-way arguments regarding the corpus callosum, the hypothalamus, the anterior commissure, and brain asymmetry.

The Corpus Callosum

One of the most popular subjects of research concerning gender-specific brain differences is the corpus callosum, a thick bundle of nerves that connects the left and right brain. For a number of years, some researchers asserted a significant difference between the thickness of the corpus callosum in males and females, typically claiming that the corpus callosum was thicker in females. Some born-this-way advocates suggested similar trait may differentiate heterosexuals from homosex...