Special Senses

This section is dedicated to our senses: touch, hearing, vision, taste, and smell.

Touch: Skin Receptors

Several kinds of receptors help us utilized our sense of touch to detect temperature, pain, pressure, and other sensations.

• Nociceptors (bare nerve endings)- help us detect pain.
• Meissner's Corpuscles- detect light pressure.
• Pacinian Corpuscles-look like thumbprints and detect deeper pressure.
• Thermoreceptors- detect temperature changes.

Hearing: the Ear.

• Moving from the outer ear (auricle) to the inner ear, we have the: tympanic membrane (eardrum), auditory ossicles (malleus, incus, and stapes), semicircular canals (filled with fluid and help maintain equilibrium), the cochlea, the auditory nerve, and the eustachian tube.
• The ear processes sound waves!
• The ear functions as our sense of hearing, as well as to maintain our equilibrium (balance).

Okay, this is a little cheezy, okay, really cheezy, but I made this song up as part of a project for medical terminology. It helps me to remember terminology for the ear, maybe it will help you. It goes like this:   "Otology, audiology, study of the ear and how we hear. Aur/i, Aur/o, Ot/o are the combining forms for ear. Otologist and audiologist, I can say and spell just fine. But otorhinolaryngologist takes a lot of time. Ear, nose, and throat doctor makes more sense to me. How 'bout even shorter? Just call this one an ENT!"

Vision: The Eyes

• Sensitivity to light does NOT equal vision!
• Vision requires two (2) components: the eyes and the capacity to form an image within the brain.
• Why? Because our eyes "see" everything upside down when it is first perceived, our brain is what actually flips the image, so it appears upright.
• Our eyes have two photoreceptors, rods (detect black/white light intensity) and cones (detect color). Both rods and cones are found in the retina.
• In animals, the tapetum lucidum amplifies available light, allowing them to have much better night vision than we do. The reflection of light from the tapetum lucidum is what you see when there is an animal in your headlights at night.

Gustation: Taste

• Found on the tongue, our tastebuds are actually chemoreceptors.
• We have five (5) primary taste sensations: sweet, sour, salty, bitter, and umami (savory, meaty).

Olfaction: Smell

• Olfactory receptors are chemoreceptors located in the nose.
• Receptor axons lead to the olfactory lobe, where they are processed.
• Olfactory receptors are important for taste as well.

Links!

Special Senses Quiz:

• http://www.ivcc.edu/caley/107/quizzes/107Q4-1.html

Parts of the Eye Quiz:

• http://www.mercksharpdohme.com/disease/glaucoma/the_eye/quiz/home.html

The Ear:

• http://www.iurc.montp.inserm.fr/cric/audition/english/ear/fear.htm