A study done in Japan conducted on keypunch operators demonstrated the benefits and
effects of odors on the body's responses. When the air was scented with lavender, errors
per hour dropped by 21%, with jasmine by 33% and with lemon 54%!! The Japanese have
now developed an environmental fragrance system that delivers scent through air conditioning ducts under computer control.

How does this work with the body? In order for a substance to be smelled, it must be
volatile. It is then capable of entering a gaseous state so that molecules can enter the
nostrils. The sense of smell is located in two regions of the nasal mucous membranes, on
the roof and upper part of both walls of the nasal cavity. There are slender nerve cells here
called olfactory cilia, covered with a thin film of mucus. In one area of the olfactory
mucous membrane regions, humans carry about 10 million olfactory nerve cells.

The human nose is highly sensitive and capable of distinguishing hundreds of thousands
of different odors even in small amounts. Methyl mercaptan, diluted to a proportion of one
molecule in fifty thousand of inhaled air, can still be detected as GARLIC. Such odors do
affect us even if we cannot consciously perceive them. When an odor is inhaled, it
stimulates the olfactory epithelium in the upper portion of the nasal cavity. This membrane
contains over 20 million nerve endings. The chemicals of the odor attach to specific
receptors to become an electrical impulse, which is amplified by the olfactory bulbs,
enlarged areas on the end of each olfactory nerve. The olfactory nerves are the only set of
cranial nerves to have direct contact with the outside environment. Most drugs or other
remedies do not have the benefit of such direct access as the essential oils through
aromatherapy do.

Researchers have demonstrated that there is a strong connection between the sense of
smell and the brain. Prenatally, if the left nasal cavity is malformed, so is the left
hemisphere of the brain. After birth, if air devoid of odors is inhaled, the brain shows further
degenerative changes. Olfactory nerve cells are also the only type of nerve cells in the
body that have shown the ability to regenerate. This should give us an idea of how
important the olfaction is.

From the olfactory bulb, the message/odor travels along the olfactory tract of the nerve
and enters the limbic system. The limbic system was previously called the rhinecephalon,
meaning "smell brain". There are many different areas of the brain, the amygdala and
hippocampus being the memory centers, playing a role in emotional responses. At this
point, odor may trigger a recent or distant memory.

Then the signal is passed on to the hypothalamus, which is the very middle of the limbic
system. This structure controls most of the involuntary and endocrine functions of the
body, along with many aspects of emotional behavior, especially fear and rage. This direct
effect that smell can have on the hypothalamus perhaps suggests why aromatherapy is
considered one of the most valuable tools in the treatment of stress and anxiety-related
problems.

Essential oils trigger different responses in everyone. Very often a person's response to
their first encounter with aromatherapy is a simple "I feel better". The importance of the
effect, whatever the complaint may be - physical or psychological, should not be
overlooked. A positive mental attitude is very important for a person's full recovery.

Some oils that have been used for counteracting depression, moodiness and lack of
confidence are: clary sage, grapefruit, jasmine and rose. They can create feeling of
euphoria.

Another part of the brain sends signals along nerve pathways to pain inhibitory centers of
the nervous system. Stimulation of this center can suppress many strong pain signals,
but can also create a sedating effect in the body due to secretion of the neurotransmitter
serotonin. Serotonin controls mood, hunger, sleep, pain and depression, among other
things. Essential oils that trigger similar responses include chamomile, cedarwood,
lavender, marjoram, Melissa and orange.

There is much information available to show how the body responds to the power of
essential oils when you inhale them and stimulate your body to react. We often take
smells for granted and don't realize the connection between them and our body's
responses.