Lecture 4 part 2

Question 1

What are sound waves? How do we hear them?

Answer 1

compression and expansion of air molecules; ear detects these brief changes in pressure

Question 2

What determines the intensity of sound waves?

Answer 2

amplitude

Question 3

What determines the pitch of sound waves?

Answer 3

wavelength

Question 4

What is the pathway of hearing?

Answer 4

1. soundwaves make eardrum vibrate
2. tiny bones in the middle ear transmit vibrations to the cochlea
3. ripples in the fluid of the cochlea bend the hair cells (on surface of the cochlea) triggers neural impulse
4. axons from these nerve cells transmit a signal to the auditory cortex

Question 5

how many dB is a normal conversation?

Answer 5

60dB

Question 6

What is place theory?

Answer 6

theory that links the pitch heard with the place where the cochlea’s membrane is stimulated; best explains high pitches

Question 8

What is frequency theory?

Answer 8

the rate at which the nerve impulses travel up the auditory nerve matches the frequency of a tone; best explains low pitches

Question 9

Touch is a mix of four distinct skin senses:

Answer 9

pressure, warmth, cold, pain

Question 10

What are the old thoughts on pain research?

Answer 10

pain=tissue damage (not true)

there is a specific pain centre in the brain

Question 11

Why do people get phantom limb pain?

Answer 11

mismatch between feedback brain expects and the feedback that it recieves

Question 12

What is the purpose of pain? (4)

Answer 12

• response to a threat
• influences action
• early warning system
• protects us from ourselves and environment

Question 13

what is nociception?

Answer 13

response to body’s sensory nervous system towards real or potential harm

Question 14

What are nociceptors?

Answer 14

nerve cell endings that initiate the sensation of pain

Question 15

What is the pathway of perceiving pain?

Answer 15

stimulus–peripheral nociceptors– spinal cord– thalamus– somatosensory cortex–limbic system–frontal cortex

Question 16

What are the roles of the thalamus– somatosensory cortex–limbic system–frontal cortex in nociception?

Answer 16

thalamus: control centre
somatosensory cortex: identify and localize pain
limbic system: emotion
frontal cortex: interprets and assigns meaning

Question 17

How does pain work? (chemical process of triggering nociceptors)

Answer 17

• cells get damaged, then produce chemicals like arachidonic acid
• cox-1/cox-2 enzymes convert acid into prostaglandins H2
• prostaglandins H2 is converted into other chemicals that do things like raise body temp, cause inflammation

Question 18

where do pain medications work?

Answer 18

enzymes cox-1 and cox-2 active sites

Question 19

How does aspirin/ibuprofen work?

Answer 19

• it blocks prostaglandins from forming
• enters enzyme active site and leaves half of itself there
• blocks channel that arachidonic acid binds to

Question 20

What are the biopsychosocial factors that influence pain?

Answer 20

• beliefs about pain
• fears/ expectations
• memories/experience/trauma
• emotional state
• personality
• attention

Question 21

What personality do people with chronic pain have?

Answer 21

• people pleasers
• overly self-critical
• need to be perfect
• overly conscientious

Question 22

What is the definition of chronic pain?

Answer 22

pain lasting more than 3 months, brain becomes more sensitive to pain and nerves amplify the messages

Question 23

How do we taste?

Answer 23

molecules of a substance are dissolved in our saliva and bind to taste receptors on taste buds

Question 24

What are the five taste receptors? What are their evolutionary purposes?

Answer 24

Sweet: energy
Salty: need sodium for physiological processes
Sour: poison
Bitter: poison
umami: proteins for tissue repair

Question 25

What are the components of flavour?

Answer 25

smell + taste + texture

Question 26

Explain the physical pathway to tasting

Answer 26

each bump on tongue=200+ taste buds
each bud has a pore with 50-100 receptors