The Special Senses, Olfaction, Gustation, Hearing & Balance, Vision

Conscious awareness of incoming sensory information Stimulus that reaches the cerebral cortex of the brain results in a sensation of that stimulus.
Are detected by receptors, two classes of receptors- General and Special senses.
General Senses
Receptors scattered through out the body. Include: temperature, pain, touch, stretch, and pressure.
Special Senses
Receptors housed in special sense organs in the head. Olfaction (smell), Gustation (taste), Equilibrium, Hearing, Vision
Speicalize structures that detect specific stimuli and transform that stimulus into electrical energy which is transmitted to the CNS.
sense of smell, These cells possess olfactory hairs where receptors for specific airborne molecules reside. Respond to chemicals to detect odors, System can recognize as many as 50-60 different primary odors as well as many thousands of other chemical stimuli.
sense of taste, receptors are housed in specialized taste buds in papillae on the surface of the tongue. 4 types of papillae, 2 of which have taste buds, Human tongue can detect 5 basic taste sensations.
Taste Sensations.
Sour (acid)
Bitter (often posions & spoiled foods)
Umami (savory or "steak")
Note: Spicy "hot" is not a special taste sensation but rather a general sense (pain)
VII Facial
Nerve impulses from taste buds in anterior 2/3 of tongue are transmitted.
IX Glossopharyngeal
Nerve impulses from taste buds in posterior 1/3 of tongue are transmitted.