people have all sorts of interesting sexual desires and fetishes.

But is being aroused by non-living objects or non-genital body parts normal?

Within the brain what you find sexy is a combination of cognitive, emotional and physical processes.

Of course the private aspect of sexual behavior has made studying fetishes challenging.

To get around this,

one study used online Yahoo groups to estimate the relative frequency of atypical sexual preferences.

Looking at 5000 online users,

researchers discovered that the greatest number of fetishes were not just of body parts

but of objects associated with body parts like shoes or headphones.

Popular groups included bodily fluids and body size

but the most popular group was by far the feet and toes.

This is because there's actually a Neurological basis for foot fetishes.

If we investigate this visual map showing which areas and proportions of the brain are dedicated to processing sensory functions,

we see that feet, toes and genitals

are all physically right beside each other in the brain.

One study was able to highlight this link between

sexual desires and brain regions with the man who experienced epileptic seizures as well as a fetish for safety pins.

After getting a partial temporal lobectomy or removing part of his brain,

both his seizures and sexual fixation on safety pins stopped.

Sexual fantasies likely developed during early experiences as this is when there is more synapse formation and neurogenesis in your brain.

Sexual imprinting is the process in which we and other animals

learn the characteristics of desirable mates at a young age,

often influenced by those who raised us.

one study found that adopted daughters end up choosing husbands with a significant resemblance to facial traits of their adoptive fathers.

Women who report having a more supportive emotional relationship with their fathers

were also more likely to choose mates with similar features to their dads than those who had negative relationships with their fathers.

But with fetishes this sexual imprinting can be with objects as well.

A study using two groups of sexually naive lab rats had one group wear a small Velcro jacket during their first sexual experience

while the other group, the control wore nothing.

When sexually mature, the control group displayed a normal copulation behavior whether wearing the jacket or not

whereas the jacket group were unable to achieve sexual arousal without their jackets.

This same study has been done with other objects and had similar results.

This could explain why a person with a leather fetish may have difficulty getting off without leather.

A separate study on rats had one group of male rat pups lie on bedding scented with lemon

and the other group lie on unscented beds.

For their first sexual experience,

they had the option of two sexually receptive females

one scented with lemon and one without.

The control group mated with either female at a normal frequency

while the lemon laying group preferred lemon scented females.

But these specific desires or preferences could be blocked by a naloxone which blocks endorphins or the feel-good neurotransmitters from binding to the opioid receptors in the brain,

thus blocking the sexual reward that is attributed with the velcro jacket or the smell of lemons.

While we know a lot about rat fetishes, there isn't much research on rare sexual preference in humans

and in the past they were often listed as mental disorders.

But while your specific sexual desires and fetishes may be unique to you and your experience,

modern science does show that having one in the first place is a normal part of being human.

And if it isn't harming you or someone else, they can exist as part of a healthy sex life.

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