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Senses

dependent on our senses of smell. With aging our olfactory function declines. In the elderly careful
monitoring of appetite is necessary due to the alterations in the olfactory function. Nutritionist suggest
giving a dual approach of supplementation of the trace minerals zinc and iron to enhance the smell and
taste senses.

Disorders of Olfaction

Anosmia
Anosmia is the lack of olfaction, or a loss of the sense of smell. It can be either temporary or
permanent. A related term, hyposmia refers to a decrease in the ability to smell. Some people
may be anosmic for one particular odor. This is called "specific anosmia" and may be genetically
based. Anosmia can have a number of detrimental effects. Patients with anosmia may find food
less appetizing. Loss of smell can also be dangerous because it hinders the detection of gas leaks,
fire, body odor, and spoiled food. The common view of anosmia as trivial can make it more
difficult for a patient to receive the same types of medical aid as someone who has lost other
senses, such as hearing or sight. A temporary loss of smell can be caused by a stuffy nose or
infection. In contrast, a permanent loss of smell may be caused by death of olfactory receptor
neurons in the nose, or by brain injury in which there is damage to the olfactory nerve or damage
to brain areas that process smell. The lack of the sense of smell at birth, usually due to genetic
factors, is referred as congenital anosmia. Anosmia may be an early sign of degenerative brain
diseases such as Parkinson's disease and Alzheimer's disease. Another specific cause of
permanent loss could be from damage to olfactory receptor neurons due to use of nasal sprays. To
avoid loss of smell from nasal sprays, use them for only a short amount of time. Nasal sprays that
are used to treat allergy related congestion are the only nasal sprays that are safe to use for
extended periods of time.

Phantosmia
Phantosmia is the phenomenon of smelling odors that aren't really present. (AKA Phantom odors)
The most common odors are unpleasant smells such as rotting flesh, vomit, feces, smoke etc.
Phantosmia often results from damage to the nervous tissue in the olfactory system. The damage
can be caused by viral infection, trauma, surgery, and possibly exposure to toxins or drugs. It can
also be induced by epilepsy affecting the olfactory cortex. It is also thought the condition can
have psychiatric origins.

Dysosmia
When things smell differently than they should.

The Sense of Vision

Vision needs to have the work of both the eyes and the brain to process any information. The
majority of the stimuli is done in the eyes and then the information is sent to the brain by the way of
nerve impulses. At least one-third of the information of what the eye sees is processed in the cerebral
cortex of the brain.

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