How signals from the genitals reach the brain
There are a huge number of nerve endings in the genital organs, which is why the genitals are so sensitive. During stimulation of the genitals, the nerves located within send signals to the spinal cord, from where they reach the brain.
Here are the nerves that transmit information from the genitals to the brain:
- The ilio-inguinal nerve transmits information from the labia majora in women, scrotum and root of the penis in men;
- The pelvic visceral nerves transmit impulses from the vagina and cervix in women and from the rectum in both sexes;
- The pudendal nerve is responsible for transmitting information from the clitoris in women and from the scrotum and penis in men.
Depending on the nerves involved, orgasm can be perceived differently. For example, in women, clitoral orgasm differs from vaginal orgasm, while in men, orgasm from stimulation of the penis will differ from orgasm with additional stimulation of the prostate.
Do not hesitate to try sex toys and new techniques: stimulating different areas of the genitals will help produce new vivid sensations.
So, through the nerves in the genitals, irritation reaches the spinal cord and then is sent to the brain.
How the brain responds to sexual stimulation
There are centers of pleasure in the brain that allow us to understand that something pleasant is happening and compel us to do it again and again.
Dr. Barry Komisaruk from Rutgers University conducted a study on female orgasm. The subjects masturbated in an MRI machine while researchers monitored brain activity at the moment of orgasm. As a result, the researchers discovered An fMRI time-course analysis of brain regions activated during self-stimulation to orgasm in women which pleasure centers are activated during climax.
First, activity is observed:
- in the genital sensory area of the cerebral cortex, which receives impulses from the genitals;
- in the thalamus, responsible for redistributing information from the senses;
- in the cerebellum, which controls muscle functions;
- in the hypothalamus — a part of the limbic system associated with emotions and hormone production.
Closer to the beginning of the orgasm and during it, the following areas are activated:
- the frontal lobes of the brain, responsible for decision-making;
- the entorhinal cortex, involved in spatial orientation and memory formation;
- the anterior cingulate cortex, responsible for emotions and motivation;
- the insula, involved in perceiving and analyzing information received from other organs;
- sections of the limbic system – the amygdala and hippocampus.
A bit later during orgasm, activation peaks:
- in the hypothalamus;
- in the accumbens nucleus, which controls the dopamine response;
- in the caudate nucleus — a part of the striatum where a large amount of dopamine is concentrated.
Also at this time, the levels of oxytocin, which increases the feeling of trust, and vasopressin, which is responsible for the feeling of attachment, rise.
Due to the release of hormones after sex, feelings of attachment and tenderness towards the partner increase.
As seen in the video below, during orgasm almost the entire brain is active. The higher the amount of oxygen in the blood in a certain area of the brain, the brighter color it is marked with. During orgasm, almost the entire brain lights up in yellow and orange, which means that almost all its areas are active.
However, in some areas of the brain, activity still decreases. This is the lateral orbitofrontal cortex, responsible for behavioral control.
Orgasm and lack of control
A team of researchers from the University of Groningen in the Netherlands, led by Janniko Georgiadis, conducted several studies on the brain activity of men and women during sexual stimulation.
Researchers found that there is practically no difference between the brain activity of men and women during sex. In both sexes, during orgasm, the area of the brain located opposite the left eye was shut down: the lateral orbitofrontal cortex, responsible for behavioral control.
Janniko Georgiadis suggests that the lateral orbitofrontal cortex may be the basis of control over sexual behavior. Perhaps only by loosening control can one achieve orgasm.
Deactivation of the lateral orbitofrontal cortex occurs only during orgasm. No other activity has been found to cause a similar effect.
It is likely that rigid control over sexual behavior prevents some people from achieving orgasm.
Also, at the peak of sexual pleasure, deactivation of the amygdala Brain Activation during Human Male Ejaculation and the entorhinal cortex, which are associated with vigilance and fear, occurs. The same suppression of amygdala activity is observed in people under the influence of cocaine. Scientists explain this by the euphoric state that occurs during orgasm as well.
However, not everyone can reach the peak of pleasure. And the reason lies again in the brain.
Possible causes of anorgasmia
Problems with achieving orgasm may be caused by insufficient amounts of dopamine or its receptors.
Sexual dysfunction is observed in 30–50% of people taking selective serotonin reuptake inhibitors (SSRIs): citalopram, sertraline, paroxetine, fluoxetine — a group of third-generation antidepressants. These medications can lower dopamine production, a neurotransmitter that provides pleasurable feelings and regulates the reward pathway — maintaining the desire of a person to repeat the action that brings pleasure.
It cannot be said that orgasm directly depends on dopamine, as after discontinuation of SSRIs, when dopamine levels return to normal, some patients still experience sexual dysfunction for a considerable time. However, dopamine certainly plays a major role in achieving orgasm. To increase your chances of sexual climax, one must ensure an adequate level of this hormone. Here’s what you can do for this:
- Get enough sleep. Quality sleep doesn’t affect dopamine levels, but it helps increase the number of dopamine receptors.
- Eat foods rich in tyrosine. The amino acid tyrosine is synthesized into the amino acid L-DOPA, which is a precursor to dopamine. Tyrosine is abundant in rabbit and turkey meat, beans, lentils, peanuts, and sesame, dairy products (cheese and cottage cheese), sunflower, and pumpkin seeds.
- Watch your weight. People with excess body weight have disturbances in dopamine synthesis in the striatum of the brain Do Dopaminergic Impairments Underlie Physical Inactivity in People with Obesity? .
I hope this knowledge will help you better understand your body and experience vivid sensations more often.
