1. A few interesting facts about Smell
In another study – a consumer test of shampoos – a shampoo which participants ranked last on general performance in an initial test, was ranked first in a second test after its fragrance had been altered. In the second test, participants said that the shampoo was easier to rinse out, foamed better and left the hair more glossy. Only the fragrance had been changed.
There is also evidence to suggest that what you think you’re smelling affects your response to an odor. In 2001, Herz and von Clef found that participants rated an identical odor as more pleasant when it was presented with a positive label (“parmesan cheese”) rather than a negative label (“vomit”).

2. A few interesting facts about Smell
Smell is extremely important when it comes to attraction between two people.  Research has shown that our body odour can help us subconsciously choose our partners.  Kissing is thought by some scientists to have developed from sniffing; that first kiss being essentially a primal behaviour during which we smell and taste our partner to decide if they are a match.
The mood-improving effects of pleasant smells may not always work to our advantage: by enhancing our positive perceptions and emotions, pleasant scents can cloud our judgement. In an experiment in a Las Vegas casino, the amount of money gambled in a slot machine increased by over 45% when the site was odorised with a pleasant aroma!

3. Smell is a chemical sense
Air carrying aromas is inhaled through mouth or nose

4. Odour molecules get trapped in mucus
The molecules “open” certain olfactory receptors on the olfactory neurons
People have about 450 different types of receptors
the receptors are like locks and the keys are the odour molecules
only certain molecule unlock certain receptors
This is a very complex process

5. Smell is unique among the senses
Olfactory receptors send signals to the olfactory bulb
Smell info then directed to
THALAMUS (like the switchboard operator of your brain)
AMYGDALA (seat of emotions)
HIPPOCAMPUS (key to memory)
CORTEX (higher thoughts)

6. Our sense of smell is 10,000 times more sensitive than any other of our senses and recognition of smell is immediate. Other senses like touch and taste must travel through the body via neurons and the spinal cord before reaching the brain whereas the olfactory response is immediate, extending directly to the brain. This is the only place where our central nervous system is directly exposed to the environment.
This is what makes smell so powerful. We don’t have time to analyse it. Other senses such as sight and sound are processed by the cognitive centres in the brain. Smell bypasses these and goes straight to the core of our being.