Psychology: A Self-Teaching Guide

closed. Neurons located near the surface of the skin are the ones that give us the

sensation of light touch.

Deep touchcan be induced by placing substantial pressure on the surface of

the skin. If someone shakes your hand too tightly or grips your arm with force,

you will experience deep touch. Deep touch is also known as the sensation of

pressure.Neurons located well below the surface of the skin are the ones that give

us the sensation of deep touch.

(a) The four skin senses are.

(b) What skin sense can be induced by placing substantial pressure on the surface of the

skin?

Answers: (a) light touch, deep touch, temperature, and pain; (b) Deep touch.

Temperatureis induced by variations in the amount of heat being conducted

to or away from the skin. When heat is being conducted toward the skin, we usu-

ally experience an increase in warmth. For example, the surrounding air temper-

ature might be raised by turning on a furnace, and heat will be conducted toward

the skin. When heat is being conducted away from the skin, we usually experi-

ence an increase in cold. For example, your bare feet will usually feel cold on a tile

surface. This is because the skin of your feet makes such good contact with the

hard surface that heat is carried away from your body. Two basic kinds of neurons

for temperature are “hot” receptors and “cold” receptors.

Painis a skin sense induced by tissue damage. A hard blow to the body or

being cut by a knife will usually cause pain. Be clear that the kind of pain being

described here is not the only type of pain. But the kind of pain associated with

the skin is called cutaneous pain.Neurons in the skin that can detect tissue damage

are the ones that give us this particular pain sensation.

(a) When heat is being conducted away from the skin we usually experience an

increase in.

(b) What skin sense is induced by tissue damage?

Answers: (a) cold; (b) Pain.

Smell: The Nose Knows

You may think to yourself, “Someone in this room is wearing a perfume that I

can’t stand!” How do you know? You can’t see the perfume. You can’t hear the

perfume. But you, with your sense of smell, know.

The sense of smell allows us to detect the presence of some, but not all, air-

borne chemical substances. The sense of smell is also known as olfaction.The

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