How does aromatherapy and essential oils work?

It is most commonly recognised that Essential Oils have appealing aromas that can trigger memories and feelings. They also have identified properties that can contact the Olfactory Nerve directly when you smell and inhale them, allowing direct interaction with the Limbic System in the brain, and then having effect on the Hypothalamus, Pituitary Gland and Cerebral Cortex. The properties of Essential Oils can also be absorbed into the blood stream either through the lungs when inhaled or by absorption through the skin when used in massage. Once inside the body they have therapeutic effect on other body organs and systems by stimulating and regulating hormonal secretions, activating thermal receptors, destroying microbes on the skin, and stimulating the immune system.