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9.1 Somatosensory Receptors

1.
Free nerve endings transmit pain signals related to mechanical, thermal, or chemical sources. They are called ________.
2 .
The area of skin in which touch can activate a touch receptor is called that touch receptor’s ________.

9.2 Somatosensation in the Central Nervous System

3.
The body surface is represented by different segments of the spinal cord, each of which is called a ________.
4 .
It is believed that the center controlling the descending inhibition of pain is located in the ________ in the midbrain.

9.3 Pain and Itch

5.
________ pain results from direct injury to nerves in the peripheral or central nervous systems and often involves a burning or electric sensation.

9.4 Pain Relief

6 .
The easiest and most common starting point to treat pain is over-the-counter (OTC) drugs, which mostly work by reducing ________.
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