Ever wondered what happens in your brain during sex?
How amazing is it when you find something that makes you feel good?
Well, an activity as old as the hills has been found to be great for boosting your health and wellbeing. Something that costs nothing and can be the source of great fun.
We're talking about sex, of course!
There really is nothing like it for getting your heart racing, your blood pumping and your muscles working; all contribute to working up a bit of a sweat and enjoying a warm glow afterwards.
While all this is taking place, have you ever wondered what happens to your brain during sex? Here's a quick guide to sex chemistry:
Sex in the name of science
There have been some intensive studies of brain activity during the human orgasm thanks to brave volunteers who have been willing to find their pleasure points inside scanning machines.
This has helped scientists to map a chain reaction that occurs, and the interplay between different parts of the brain and nervous system.
Breaking down the neurological response
The first stage is your genitals becoming aroused, as they are communicating with the emotional control centre of your brain – the limbic system. 
This includes stimulation of your hippocampus, the part of the brain that deals with memory and fantasy. So this gives you an explanation for why, when you're aroused, your brain starts playing around with all sorts of sexual notions, thoughts and ideas.
The brain’s reaction to erotic stimulation across your body is to produce particular types of neurochemicals. These are like chemical messengers travelling around your nervous system, communicating, supporting emotional and physical responses, and connecting everything up. 
Pleasure and pain connection
Interestingly though, part of the brain that becomes stimulated by sexual activity is responsible for both pleasure and pain receptors. As sex continues, the activity in this part of your brain gets more intense, which explains why heightened sexual sensation can sometimes seem closely related to pain.
It could also explain why some people get sexual pleasure from creating pain during sex, such as biting and hair pulling.
And then there's the orgasm
All this heightened sensitivity and sensation caused by the different parts of your brain receiving stimulation can build to a crescendo.
This flood of neurochemicals working together around your body builds to such a level of intensity that your neural network is all joining the party.
As the climax occurs, the increased muscle tension – then the release – are all part of the brain’s natural response to intensifying sensations.
At this point, your body releases hormones that also add to the fireworks and are responsible for the afterglow.
This includes oxytocin. This neurotransmitter (created during sex by the hypothalamus) can sometimes trigger powerful uterine contractions in women – that pulsing sensation some get during orgasm.
The brain’s reward for this continues onwards.
Post-orgasm, you could well benefit from a rush of a hormone called dopamine, a chemical which is closely associated with pleasure and reward. Dopamine is synthesised from the amino acid tyrosine, before being released from neurons in your brain. It floats in the space between one neuron and another, 'bumping' against receptors which then sends a signal to the receiving neuron. 
That zoned out feeling that can occur following sex? That is – in effect – your brain 'rebooting' itself after all that stimulation and activity.
All very scientific and interesting. Armed with that insight, now you can relax and enjoy!