Root Words
Penrose Stairs
Link 

Sensation: Occurs when the brain becomes aware of sensory
impulses

Perception: Occurs when the brain interprets those sensory
impulses.
5 Types of Receptors

Chemoreceptors

Stimulated by changes in chemicals
5 Types of Receptors

Chemoreceptors


Stimulated by changes in chemicals
Pain Receptors

Stimulated by pain receptors
5 Types of Receptors

Chemoreceptors


Pain Receptors


Stimulated by changes in chemicals
Stimulated by pain receptors
Thermoreceptors

Changes in temp.
5 Types of Receptors

Chemoreceptors


Pain Receptors


Stimulated by pain receptors
Thermoreceptors


Stimulated by changes in chemicals
Changes in temp.
Mechanoreceptors

Changes in pressure or movement
5 Types of Receptors

Chemoreceptors


Pain Receptors


Changes in temp.
Mechanoreceptors


Stimulated by pain receptors
Thermoreceptors


Stimulated by changes in chemicals
Changes in pressure or movement
Photoreceptors

Changes in light energy
Touch and Pressure

Touch and pressure derive from 3 kinds of receptors



Free Nerve Endings
Tactile (Meissner’s)Corpuscles
Lamellated (Pacinian)Corpuscles
Free Nerve Endings

Located in Epithelial
Tissue.

Responsible for
sensation of itching
Tactile (Meissner’s)

Oval, connective
tissue

Hairless portion: lips,
fingertips, palms

Sensation of light
touching
Lamellated (Pacinian)

Large connective
fibers

Deeper dermal and
subcutaneous tissue

Senses heavy
pressure
Engaging all pressure
senses
PAIN!!!!

Pain is good, pain
receptors protect the
body from further tissue
damage.

Pain adapts poorly.
Thus, persistent pain
does not fade

Visceral Pain: Pain in
organs (Only receptors
in viscera)
Special Senses (because
you’re “special”)
-
Smell
-
Taste
-
Hearing
-
Equilibrium
-
Sight
Taste

Taste Buds:
chemoreceptors
located primarily on
the tongue

Roughly 10,000 taste
buds on tongue.
~1,000 on roof of
mouth

Each “bud” includes
50-150 Taste Cells

Salivary gland
provides fluid for
chemical to enter
taste cell
5 Taste Sensations
1.
Sweets
2.
Sour
3.
Salty
4.
Bitter
5.
Umami (Japanese
term meaning
delicious)

Taste map is misconception, there are equal taste cells
throughout the tongue