Smell Disturbance Anatomy
To better understand altered smell sense, it helps to understand the anatomy of the nasal passages.
Nerves that sense odors are located in the upper part of the nose. Impulses are then sent to several areas of the brain where smell is interpreted and kept in memory.
The sense of smell is related to the sense of taste. People with a poor sense of smell also tend to have a decreased ability to taste.
- Busenbark, K.L., Huber, S.I., Greer, G., Pahwa, R. & Koller, W.C. Olfactory function in essential tremor. Neurology 42:1631-1632, 1992. 
- Deems, D.A., Doty, R.L., Settle, R.G., Moore-Gillon, V., Shaman, P., Mester, A.F., Kimmelman, C.P. Brightman, V.J. & Snow, J.B., Jr. Smell and taste disorders: A study of 750 patients from the University of Pennsylvania Smell and Taste Center (1981-1986). Archives of Otolaryngology -- Head and Neck Surgery 117:519-528, 1991.