Term (literally "concerning the olfactory nerve") for the perception of the smell (olfactus = smell) via the nose in contrast to the perception of the taste via the tongue and the palate. The olfactory nerve (lat. Olfactory nerve) is the first and shortest of the 12 cranial nerves. It is for the transmission of the smell impressions from the olfactory mucosa (2 x 5 cm²), which is twice the size of a postage stamp, in the upper nasal cavity area with 20 million olfactory cells ( receptors ) responsible for the primary olfactory cortex in the cerebrum. The sense of smell is the most complex chemical sense. It depends on the individual amount of an odorant, from when it is perceived. This is called Perceptual threshold (Perception limit).
As part of a wine review (Tasting) or wine address (Description) is sometimes differentiated into "nasal" (also pronasal or orthonasal) when inhaling through the nose and "retronasal" when exhaling through the nasopharynx. However, there are two in the sense of smell sensory Systems involved. In addition to the olfactory system, this is also the nasal-trigeminal system with a share of around 30%. odor and the taste but interact and influence each other; an exact distinction is therefore not possible. See the other two senses below gustatory (tasting) and trigeminal (tactile = groping, touching).