7.2 The Mechanical Senses

Question 1

Somatosensory system

Answer 1

Sensory network that monitors the surface of the body and its movements

Question 2

Semicircular canals

Answer 2

Structures located in the vestibular organ, oriented in three planes and lined with hair cells; sensitive to the directional tilt of the head

Question 4

Pacinian corpuscle

Answer 4

Reseptor that responds to a sudden displacement of the skin or high-frequency vibrationd on the skin

Question 5

Substance P

Answer 5

A neurotransmitter released by pain axons in the spinal cord

Question 7

Capsaicin

Answer 7

A chemical, found in hot peppers, that produces a painful burning sensation by releasing substance P; high dosages damage pain receptors

Question 8

Dermatome

Answer 8

Area of the body connected to a particular spinal nerve

Question 10

Periaqueductal gray area

Answer 10

Area of the brainstem that is rich in enkephalin synapses

Question 11

Opiod mechanisms

Answer 11

Systems that respond to opiate drugs and similar chemicals

Question 12

Placebo

Answer 12

A drug or other procedure with no pharmacological effects

Question 15

Endorphins

Answer 15

Transmitters that attach to the same receptors as morphine

Question 17

Gate theory

Answer 17

Idea that stimulation of certain axons can close the “gates” for pain messages