One of the best ways to use essential oils is Inhalation.

The sense of smell is the only one of the five senses that are linked directly to the limbic or the emotional brain. This area of the brain includes the: Olfactory Bulb, Hippocampus, Amygdala and the Hypothalmus
With inhalation the olfactory bulb or the nerves in your nose are stimulated by the small essential oil molecules which then send a signal to different parts of the limbic brain.
The Amygdala is involved in processing our basic emotions like joy, fear, anxiety, anger... and deciding which memories are stored & where.

The Hippocampus processes our long-term memories as well as our recollection of facts and events.
The Hypothalamus is considered the hormone control centre of the body, it works with the pituitary gland to stimulate different processes in the body like appetite, sleep cycles, your sex drive, and blood pressure among others.
How it works
For example, if you use a relaxing essential oil for inhalation, different parts of the limbic brain go to work releasing neurochemicals and hormones to slow your heart rate and help to lower blood pressure.
How to use essential oils for Inhalation:
-use a personal inhaler up to 4 times per day as needed (dependant on age, health of person using it)
- use a candle or ultrasonic diffuser (Use for 30 - 60 minutes, 2 - 3 times per day or use the intermittant setting on the ultrasonic diffuser.)
How Safe is Inhalation?
According to author & aromatherapist, Robert Tisserand ” (inhalation) from a safety standpoint presents a very low risk to most people”.
“Inhalation is still the quickest method of absorption in therapeutic aromatherapy. Topical applications come in second and should be applied to the areas of concern. “Amy Kreydin, The Barefoot Dragonfly.
My Blog is for general information only & is not meant to diagnose or replace medical advice.
Essential Oils are for external use only & should always be diluted before topical use.My blog doesn't include all of the precautions or possible interactions that may occur.
References:
http://www.amykreydin.com/10-epic-essential-oil-myths-and-dangerous-uses-of-2014/
http://thebrain.mcgill.ca/flash/d/d_05/d_05_cr/d_05_cr_her/d_05_cr_her.
http://www.brightfocus.org/alzheimers/infographic/brain-anatomy-and-limbic-system
http://www.quinessence.com/blog/the-limbic-system
http://www.healthline.com/human-body-maps/hippocampus
http://www.healthline.com/human-body-maps/amygdala
http://www.healthline.com/human-body-
Photos are from Canstock photo. The Limbic brain is from Dreamstime.com/