Sex , Brain and Neurochemistry : The Perfect Pleasure Cocktail

• Sex is not only felt — it’s processed.

Have you ever wondered why someone can stop thinking with their head and start feeling with their entire body when desire kicks in? Did you know your brain mixes hormones, emotions, and chemistry into a true sensory explosion?

We all know how complex the brain is — made up of 60% fat, with a storage capacity considered limitless, and information traveling between neurons at an estimated speed of 268 mph (431 km/h). It’s a curious organ, and its involvement in sex is incredibly intricate. With this article, I aim to help readers better understand its fascinating role.

• Pleasure hormones: the chemicals of desire

A key piece in all of this: hormones. But what exactly are they? Hormones are chemical substances secreted into the bloodstream by specialized cells, whose goal is to instruct other cells to perform specific functions.

During sexual activity, the brain coordinates an increase in breathing and heart rate, along with peripheral vasodilation, which makes us blush. The skin becomes more sensitive, sensory and nerve endings become sharper, and the body becomes more responsive to touch. The adrenal gland produces steroids, epinephrine, and norepinephrine, which control heart rate, blood pressure, and other bodily functions.

Soon after, cortisol production rises, increasing blood glucose levels to provide energy. Other hormones that are part of this wonderful cocktail include insulin and glucagon. During sex, even the body’s pH changes, which makes us breathe faster, decreasing oxygen concentration in the brain and heightening excitability.

Thyroid hormones are also released, keeping the metabolism active so energy doesn’t run low at a critical moment. Hormones released by the kidneys activate the renin-angiotensin-aldosterone system, which retains sodium and water — so when we sweat during sex, we don’t dehydrate as easily.

Dopamine helps us feel more pleasure and satisfaction, while oxytocin — often called “the love hormone” — makes your partner appear more attractive and emotionally valuable during the act.

• Between hormones and emotions: feelings also have a brain map

I mentioned at the beginning that the brain mixes hormones, chemistry, and emotions during sex. It’s important to understand what these emotions are and how they occur. Emotions are combinations of various hormones, like those mentioned above. Different areas of the brain are involved in emotional responses to reality — especially the limbic system. Within this system are the amygdala and hypothalamus, which is considered the emotional center of the brain.

The relationship between emotions and the brain is bidirectional — the brain influences the generation and regulation of emotions, and emotions, in turn, can affect brain function and performance.

The limbic system is essential for processing, interpreting, and regulating emotions, whether they arise from internal or external stimuli. In other words, this system gives meaning to emotions and adjusts them according to the situation. In the case of sex, we can observe how hormonal changes trigger a wide range of physiological changes.

• Orgasm and the brain: when the body shuts down and pleasure erupts

An orgasm involves a central activation that engages multiple brain regions — the sensory cortex, limbic system, and hypothalamus are among the key players.

An orgasm is the intense and pleasurable climax of sexual arousal, characterized by rhythmic contractions of pelvic floor muscles, a surge of pleasure, and a following sense of relaxation and satisfaction.

But what if we defined orgasm more technically? It would be something like: the peak intensity of arousal generated by afferent and reafferent stimulation of visceral and/or somatic sensory receptors, triggered exogenously and/or endogenously, associated with higher-order cognitive processes, followed by release and resolution (decrease) of arousal.

It sounds complex — and it is — all thanks to the nervous system.

In this context, the emotional and phenomenological experience of orgasm has been linked to the deactivation of certain brain areas, such as the prefrontal, temporal, and entorhinal cortex. This is interpreted as an enhanced perception of pleasure and a sensation of fullness that accompanies the sensory climax.

Based on current research, it’s not entirely clear whether the brain controls the orgasm — or whether the orgasm controls the brain. In fact, some studies show that many areas deactivate at the peak of sexual climax, suggesting that the brain almost “shuts down,” except for the brainstem (which controls cardiovascular activity) and the cerebellum (responsible for movement).

• Why do some people feel emotions incompatible with sex?

This is a topic I intend to explore more deeply in future articles, as it’s both complex and common. Although biologically we are designed to respond to sex with desire, pleasure, and connection, human emotional reality is far more complicated. It’s not all about hormones and neurotransmitters — personal history, past experiences, and psychological context also shape our sexual experience.

The brain stores emotional memories, and if someone has lived through a negative experience — trauma, coercion, shame, or even a repressive upbringing — that memory can be unconsciously triggered during sexual situations. In such cases, emotions like fear, guilt, rejection, or anxiety may replace desire, even when the body reacts “normally” on a physiological level.

That’s because the limbic system not only processes pleasure — it also processes emotional pain, and it may prioritize protection over enjoyment. The amygdala, which governs intense emotional responses, may go into alert mode in situations that, for others, would trigger arousal.

We also can’t forget the role of the prefrontal cortex — the brain’s rational control center. If there’s an internal narrative of conflict, negative beliefs about sex, or low self-esteem, this part of the brain may “block” or inhibit sexual desire, even if other brain regions are ready to enjoy.

In short, sex is not just felt by the body — it’s also negotiated through each person’s emotional history. That’s why understanding the brain is also a way of reconciling with our own sexuality.

Conclusion

Sex is not just skin on skin — it’s synapse on synapse. Every touch sparks circuits. Every orgasm shuts down brain areas and resets others — like a hard reset of pleasure. At its core, making love is also doing neuroscience with your body. And now that you know everything that lights up up there when you surrender to it… how can anyone resist the erotic mystery of the brain?

References:

Urbeconomica. (2023). Sex: A neurochemical party. Retrieved from: https://www.urbeconomica.com/columnistas/pienso-luego-existo/42943-el-sexo-una-fiesta-neuroquimica

Northwestern Medicine. (2025). 11 curious facts about the brain. Retrieved from: https://www.nm.org/healthbeat/healthy-tips/11-datos-curiosos-sobre-el-cerebro

National Autonomous University of Mexico (UNAM). (2022). Sex: What happens in your body?. Retrieved from: https://unamglobal.unam.mx/global_revista/sexo-que-pasa-en-tu-cuerpo/

Bupa Health. (n.d.). Emotions and the brain. Retrieved from: https://www.bupasalud.com/salud/emociones-y-cerebro

National Geographic Spain. (2024). What happens in the brain during orgasm? Neuroscience explains it. Retrieved from: https://www.nationalgeographic.com.es/ciencia/que-ocurre-en-cerebro-cuando-tiene-un-orgasmo-neurociencia-explica_21602

NeuronUP. (2022). The sexual brain: Neuroscience and sex-related differences. Retrieved from: https://neuronup.com/neurociencia/cerebro-neurociencia/el-cerebro-sexual-neurociencia-y-diferencias-ligadas-al-sexo/

This article includes AI-assisted content