Sexual Orientation - Nature or Nurture?

The subconscious development of sexual orientation during childhood

(Based on: The roots of sexual arousal and sexual orientation, Y. Salu, Medical Hypotheses 76 384-387 2011.   A pre-print copy:  http://www.micropsychology.org/the-roots-of-sexual-arousal-and-sexual-orientation/

SUMMARY: A baby’s brain has innate neural networks that serve as a core around which activity plans are built. The activity plans, which are developed subconsciously, are used later on by the brain for controlling mental and physical activities. For example, our ability to identify foods by their appearance and to think about them can be traced back to neural networks that we are born with. Those networks, which are connected to our taste buds, detect certain nutrients such as sugars, fats and salts that are present in the food that we chew. At the same time, subconscious brain mechanisms detect visual features of that same food, and build from them mental perceptions of foods. Based on those perceptions we can identify foods by their looks, imagine how they might taste, decide if we want to eat them, and so on. Those learned perceptions and their accompanying activity plans are recorded in the brain’s neural networks.

Identifying the sex of another person is the crucial first stage in any sexual interaction. Activity plans for identifying the sex of other people based on arbitrary cues, such as their clothes, are developed during childhood. A baby’s brain has innate neural networks that can distinguish between the voices of men and women. Those auditory networks are the core around which the activity plans for identifying the sex of other people are developed. Those core auditory neural networks must have connections to centers that control the physical aspects of sexual behavior. The innate connections between the auditory and the sex control networks determine the sexual orientation of a person at puberty. 

The details of the connections between those innate auditory and sexual control networks may vary from one baby to another. Those variations affect how the sexual activity plans evolve during childhood and eventually emerge at puberty, expressing the sexual orientation of the person. It all depends on which voice detection network is innately connected to the sexual control network. If a baby’s network that detects men’s voice is innately connected to the sexual control network, then at puberty that baby will become sexually attracted to men. If a baby’s network that detects women’s voice is innately connected to the sexual control network, then when reaching puberty that baby will become sexually attracted to women.

Nature and Nurture

Many of our behaviors have components that we are born with and components that we learn. For example, speech communication. We are born with organs that produce speech, organs that can hear it, and a brain that controls speaking and hearing and relates them to our other activities. These are the ‘nature’, or the innate components of speech communication. The language that we speak is the ‘nurture’, or the learned component. Innate learning mechanisms fuse the external information that we learn with the parts of the system that we are born with. Those learning mechanisms enable us to learn the language subconsciously from the surroundings in which we grow up. In addition, there are also innate mechanisms that enable us to learn language cognitively, by being taught by others.

Sexual Attraction

Sexual behavior is a complex behavior. It is divided into sub-behaviors according to the sexual orientation of the involved individuals. We say that a person is engaged in a homosexual act when he or she are of the same sex as their sex partners. We say that the act is heterosexual when the participants are of opposite sexes. (Those definitions apply also when a person is fantasizing and the partner is not a real person.)

A sexual event progresses in stages. First, a person has to identify a suitable partner. Let’s call that person recruiter, and his or her partner target. The target has to possess features that arouse the recruiter. Once a contact between the two is made, they usually arouse each other throughout the event.

In some animals sexual interaction is controlled by pheromones. One partner has innate organs that release molecules of pheromones into the air. Those molecules are picked up and recognized by innate organs of the second partner. That triggers that partner’s motion toward the first one, using innate motion mechanisms. The two then meet and mate using innate mechanisms that coordinate their activities. Humans do not use pheromones for identifying their partners and connecting with them. In general, we do not have organs and innate mechanisms that are dedicated solely to identifying sexual partners.

During childhood, the sex organs are still developing, and adult-like sexual arousal does not exist. Human sexuality emerges at puberty; young men and women suddenly feel sexual attraction to other people. Already then, the attraction is hetero- or homo-sexual. The youngsters have acquired those traits subconsciously, on their own, during childhood, by just being embedded in the society in which they grew up. This has been happening throughout history, in any society, all around the world. Since visual cues that humans use for identifying their sex partners vary significantly with local fashion habits, and since humans do not communicate by pheromones, humans must be relying on innate learning mechanisms that teach them how to identify their sex partners. Those learning mechanism must rely on innate universal cues that distinguish between men and women, and that can be easily noticed by the children as they grow up. Human sexual orientation that emerges at puberty is the outcome of those innate, subconscious learning mechanisms.

Innate Learning Mechanisms

One subconscious learning mechanism is grouping-by-association. This mechanism groups together different items that are associated with a common cue. For example, foods that trigger salt detectors in our mouth are grouped in our mind as a group: salty food. Individuals that are nice to us are grouped in our mind as a group: nice people, and so on. In the case of salty food, the grouping is based on an innate cue; salt sensors are innate. In the case of friendly people, the grouping is based on learned cues. Once the brain forms a group, it keeps adding to it new members as they occur. The brain then treats the group as one entity in its thoughts. For example, we may decide to avoid salty food, or to befriend nice people.

Conditioning is another set of subconscious learning mechanisms. In the famous Pavlov’s experiments, dogs learned to salivate when they heard a bell’s ring that was associated with tasting food, which triggered salivation. In general terms, something that is associated with a trigger of an activity becomes also a trigger of that activity. Quite often, conditioning and grouping-by-association work together. For example, if a bell’s ring is first associated with a flash of light, and then a dog is conditioned to salivate to the bell’s ring, the dog would salivate also to the flash of light, even though it was not part of the training to salivate.

Grouping-by-association and conditioning build new behaviors around innate cues and innate behaviors. They are the underlying subconscious mechanisms that the brain employs during childhood, as it builds the sexual orientation that emerges at puberty.

Subconscious Development of Sexual Orientation

Using grouping-by-association, children learn subconsciously to distinguish between men and women. To achieve it, they must rely on an innate universal cue that children can detect, and which distinguishes between men and women. (Adult’s sex organs distinguish between men and women, but quite often they are not visible to children.)  One such cue, and probably the only one, is human voice. We can identify the sex of people by hearing their voice. This is the case everywhere around the world, and it has been so for millennia. At first, infants subconsciously form in their minds perceptions about two groups of people: one group, women, includes people with high-pitch voice. The other group, men, includes people with low-pitch voice. As they grow up, children encounter other local cues, such as clothing or hair styles, which are typical to each sex in the child’s local environment. The children use those local cues in addition to the voice when they identify the sex of a person.

The brain has auditory centers that process sound, and sex-control centers that control sexual activities. Certain auditory circuitries are innately tuned to distinguish between the voices of men and women. The specific innate connections between those circuitries and the sex-control centers determine the sexual orientation of the person at puberty.

When the auditory centers detect certain sound patterns, they send signals that can trigger the sex-control centers. In children, the undeveloped sex organs cannot be activated by the sex-control centers. However, by conditioning and by grouping-by-association, circuitries are developed subconsciously that enable the brain to distinguish between the sexes, and to activate the sex-control centers based on those distinctions. Those circuitries and connections become fully functional at puberty, and they determine the person’s sexual orientation. This is analogous to learning processes in other animals. For example, the dog’s salivation organs are the analog of the sex organs. The neural circuitry that controls salivation is the analog of the circuitry that controls sexual functions. The taste sensors are the analog of the auditory sensors. The cues that are associated with the innate taste sensations are the analog of the cues that are associated with the innate sensations of voice. Similarly to the dog that learns to salivate to the sound of a bell, a human learns to be sexually attracted to other humans by the way that they are dressed and look.

The Nature Component of Sexual Orientation

More specifically, the sexual orientation of a person is developed subconsciously from innate brain circuitries in the brain of that person as follows:

  • A boy whose innate auditory circuits that detect high pitch voice are connected to his sex control center will be attracted to women. He will become straight at puberty.
  • A boy whose innate auditory circuits that detect low pitch voice are connected to his sex control center will be attracted to men. He will become gay at puberty.
  • A girl whose innate auditory circuits that detect low pitch voice are connected to her sex control center will be attracted to men. She will become straight at puberty.
  • A girl whose innate auditory circuits that detect high pitch voice are connected to her sex control center will be attracted to women. She will become lesbian at puberty.
  • Children whose innate auditory circuits that detect high pitch voice and those that detect low pitch voice are both connected to the sex control center will be attracted to both men and women. They will become bi-sexual at puberty.

The gender of the target is a necessary feature that the recruiter is looking for. However, this is not the only feature. There are additional features that the target broadcasts such as looks and readiness, and cues from the surroundings such as available amenities, safety, and so on. The brain integrates those cues, and based on all of them decides whether to arouse the body and continue the sexual activity, or to turn it off.

While the sexual orientation of people had been established subconsciously by the time they have reached puberty, they continue to adopt new arousal cues and to develop new behavior patterns. Those cues and behavior patterns are learned, among other ways, from gratifying sexual experiences, and from being told by others.

Additional reading

The role of the amygdala in the development of sexual arousal, Y. Salu, Electronic Journal of Human Sexuality Vol 16, June 9, 2013 http://ejhs.org/volume16/Amygdala.html    A pre-print copy: http://www.micropsychology.org/sexual-arousal-and-the-amygdala/

Micropsychology: The roots of mental function and sexuality, by Yehuda Salu