Sex Drive Explained by Neuroscience

By Adriana Pasarari

1. Your brain predicts everything you do

Your brain predicts everything you do. Our brain makes predictions based on the information we have accumulated up to the present moment (Barrett, 2020). This also applies to sex drive. By drawing on your knowledge of sexuality and past sexual experiences, your brain anticipates when you will feel sexual arousal. When you encounter stimuli associated with sexual pleasure, your brain predicts another enjoyable sexual experience and prepares your body for sexual intercourse.

Sex drive can’t be explained solely by neuroscience; your body functions as a system, so multiple factors influence your sex drive. The endocrine system, psychological factors, and the society we grew up in all affect an individual’s sexuality. Negative past sexual experiences can alter how your brain predicts sexual arousal, potentially leading to a diminished or absent sex drive. Furthermore, if you are physically or emotionally exhausted, your brain lacks the energy to make predictions, which can contribute to a reduced sex drive.

2. Sex drive as a reward system

Sex drive as a reward system: Sex can be viewed as a reward system, with the reward varying from person to person—it may be an orgasm, a sexual encounter itself, or an emotional connection.

The following neurotransmitters play a role in sex drive:

>  Steroid hormones prepare the brain to receive sexual stimuli. This preparation occurs when androgens, estrogens, and progestins bind to specific hormone receptor complexes. This process leads to the synthesis of various neurotransmitter receptors, creating a neurochemical state in which sexual stimuli are selectively attended to and are more likely to provoke sexual responses. Steroid hormones activate mechanisms of sexual excitation by directing the synthesis of enzymes and receptors for several interactive neurochemical systems.  These include dopamine, norepinephrine, melanocortin, and oxytocin systems operating in hypothalamic and limbic regions of the brain to stimulate sexual arousal, attention, and behaviors related to both plasma testosterone and hyperprolactinemia (Pfaus J. G., 2009, p.1510). 

>   Dopamine, aside from its key role in the reward system, stimulates the autonomic nervous system—encouraging genital blood flow through the parasympathetic system.

>    Norepinephrine contributes to sexual motivation; however, high levels can provoke a state of fear.

>   Oxytocin, a neuropeptide, is often called the 'bonding hormone' due to its role in sexual behavior.

>   Serotonin is linked to satiety and sexual inhibition

(Pfaus J. G., 2009).

>  dopamine, norepinephrine, oxytocin, and adrenaline enhance sex drive, while serotonin, endorphins, prolactin, progesterone, and cortisol inhibit it (Sayin, H. Ü., 2019).

3. Neuroimaging human sexual response

Neuroimaging in human sexual response: Ruesink and Georgiadis (2017) indicate that neuroimaging reveals a "sexual wanting pattern" present in the occipitotemporal cortex, superior parietal lobule, ventral striatum, amygdala/hippocampus, orbitofrontal cortex, anterior cingulate cortex, and anterior insula, along with a “sexual liking pattern” that includes the hypothalamus, anterior and posterior insula, ventral premotor cortex, middle cingulate cortex, and inferior parietal lobule (p. 185).

The discussion can continue into the differences in sex drives between genders; however, it would be unfair to address this and review studies on the topic in a world where there remains such stigma surrounding women’s sexuality. Yes, the biological factor is significant for any individual’s sex drive, but can we accurately measure it with statistical tools when the societal factor is so predominant?

References

1. Barrett, L. F. (2020). Seven and a half lessons about the brain. Houghton Mifflin Harcourt.

2. Pfaus, J. G. (2009). Pathways of sexual desire. The Journal of Sexual Medicine, 6(6), 1506–1533. https://doi.org/10.1111/j.1743-6109.2009.01309.x

3. Ruesink, G. B., & Georgiadis, J. R. (2017). Brain imaging of human sexual response: Recent developments and future directions. Current Sexual Health Reports, 9, 183–191. https://doi.org/10.1007/s11930-017-0123-4

4. Sayin, H. Ü. (2019). Getting high on dopamine: Neuroscientific aspects of pleasure. SexuS Journal, 4(11), 883–906.