Special Senses

Chemical Senses

Olfaction

Nasal Cavity

Nasal Bones: Models

Nasal Bone: Drawings

Nasal Cavity Lining

Olfactory Epithelium Location

Olfactory Mucosa

Olfactory Receptor Cells (OC)Basal Cells (BC)Sustentacular Cells (SC)

Olfactory Bulb

Olfactory Modalities

Aromatic Fragrant Repulsive Ethereal Resinous Spicy Burned Putrid

Gaseous or Volatile Liquids16 Chemical Elements produce Odor Sensation

Smell Physiology

Olfactory Tract

CN I and Rhinencephalon

CN 1 enteringBase of brain atOlfactory Gyrus

Olfaction and the Limbic System

Gustation

Tongue Anatomy

Tongue Papilla

Taste Bud Histology

Taste Bud Stimulus

Taste Maps

Sweet– Responds to sugars– Responds to AA

Sour– Responds to H+

Salty– Responds to NaCl, salts– Responds to metal ions

Bitter– Responds to alkaloids

Areas of Innervation

Taste Sensations

TemperatureConcentrationOrderInteraction

Nerves for Taste: CN VII, IX, XII

Chorda tympani of CN 7 Lingual Branch of CN 9 Pharyngeal Branch of

CN 10

Myelinated Delta A fibers go to the Nucleus Tractus Solitarius Thalamus Parietal Lobe

Gustatory Pathway

CN VII, IX, X Medulla Thalamus Parietal Lobe: Gustatory Cortex

Effects on Taste

Smell Temperature of food Texture of food Visual appearance of

food

Problems

Glossitis

Cancer of the Tongue