Lust
Lust is driven by initial physical attraction and flirting. In this stage, flirting can include gazing into the eyes, touching, and mirroring in body language. The two chemicals that surface during this stage are the sex hormones (testosterone and estrogen) and pheromones.**The existence of human pheromones was discovered in 1986, finding these chemicals in human sweat **
Falling in love
When you fall in LOVE, you may have many physical symptoms include lose of appetite, insomnia, losing concentration, palms sweat, butterflies in stomach and so on. This is due to the surging of brain chemicals called : DOPAMINE
it's commonly associated with the pleasure system of the brain which provides feelings of enjoyment. It's released by naturally-rewarding experiences such as sex or food.
SEROTONIN
It controls impulses, unruly passions, obsessive behavior. Serotonin is also necessary for normal male mating behaviour.
PHENYLETHYLAMINEIt's a natural amphetamine like the known drug and can cause the same stimulation effects. It contributes to that on-top-of-the-world feeling and gives you the energy.
NOREPINEPHRINE
Its a neurotransmitter which induces euphoria in our brain which excites the body by giving a booster dose of natural adrenaline. This causes the heart to beat faster and blood pressure rises. Therefore, you can experience a pounding heart or sweaty palms when you see someone you're attracted to.
Attachment - Staying together
There is a sense of calm and stability that we feel with a long-term partner, a sort of bond that keeps couples together. This kind of love is driven these hormones:OXYTOCIN
it's sometimes known as "the cuddle chemical". It's the hormone best known for its role in inducing labor by stimulating contractions. In humans, oxytocin is thought to be released during hugging, touching and orgasm in both sexes. In the brain, oxytocin is involve in social recognition and bonding and may be involve in the formation of trust between people and generosity.
VASOPRESSIN
It also called as "the monogamy chemical". Researchers have found that suppression of vasopressin can cause males to abandon their love nest and seek new mates.
ENDORPHINSOur happiness is created by endorphins. Endorphins are natural hormones released from the brain to control our mood. It gives a sense of pure hapiness, well being and satisfaction. They are also biochemical compounds that enhance our immune system, block the lesion of blood vessel, anti-aging, anti-stress and pain-relieving effect and also help to improve our memory.