8.2 multisensory intergration

Question 1

What are the 3 main auditory systems?

Answer 1

• outer ear
• midddle ear
• inner ear

Question 2

What part of the ear amplifies vibrations?

Answer 2

middle ear

Question 3

What part of the ear contains hair cells that transduce sound?

Answer 3

inner ear

Question 4

How does sound become a neural signal?

Answer 4

• Sound waves vibrate the eardrum
• move the ossicles
• push the oval window of the cochlea

Question 5

Hair cell activation produces neural impulses sent via the auditory nerve to which 3 brain areas?

Answer 5

• the inferior colliculus
• the medial geniculate nucleus (thalamus)
• the audiatory cortex (temporal lobe)

Question 6

Which 2 theories explain how we perceive pitch?

Answer 6

• temporal theory
• place theory

Question 7

How does the temporal theory work?

Answer 7

Hair cells fire action potentials at a rate that matches the sound frequency. (only low frequencies)

Question 8

How does place theory work?

Answer 8

The different parts of the basilar membrane respond to different frequencies

Question 9

Does the base of the basilar membrane respond to high or low frequencies of sound?

Answer 9

high frequencies

Question 10

Does the tip of the basilar membrane respond to high or low frequencies of sound?

Answer 10

low frequencies

Question 11

Which frequency of sound relies on place coding?

Answer 11

higher frequencies (above 4,000Hz)

Question 12

How do monaural cues work? (one ear)

Answer 12

shape of the inna alters sound dependent on vertical position (above/behind/in front)

Question 13

What is the role of binaural cues? (two ears)

Answer 13

used ro locate sounds along the horizontal axis

Question 14

What are the 2 key differences that help the brain determine direction? (binaural cues)

Answer 14

• interaural level differences (sound is louder to closer ear)
• interaural timing differences (sound reaches one ear earlier)

Question 15

What is conductive hearing loss?

Answer 15

when sound cannot reach the cochlea

Question 16

What is sensorineural hearing loss?

Answer 16

damage to the inner ear/ audiatory nerve

Question 17

How is conductive loss treated?

Answer 17

hearing aids

Question 18

can sensorineural loss be treated with hearing aids?

Answer 18

no, but choclea implants can help

Question 19

Why are taste and smell chemical senses?

Answer 19

their receptors resond to molecules

Question 20

What areas of the brain are involved with taste bud receptors?

Answer 20

medulla, thalamus, limbic system and gustatory cortex

Question 21

What is the role of olfactory receptors?

Answer 21

to send signals to the olfactory bulb then limbic and cortical areas in response to odor molecules.

Question 22

What are pheromones?

Answer 22

chemical signals used for communication

Question 23

What are the 4 specialised receptors on the skin?

Answer 23

• Meissner’s corpuscles
• pacinian corpuscles
• Merkel’s disks
• Ruffini copuscles

Question 24

What on the skin is detected by Meissner’s corpuscles?

Answer 24

light pressure, low frequency vibration

Question 25

What on the skin is detected by the pacinian corpuscle?

Answer 25

deep pressure, high frequency vibration

Question 26

What on the skin is detected by Merkel's disks?

Answer 26

light, substained pressure

Question 27

What on the skin is detected by Ruffini corpuscles?

Answer 27

skin stretch

Question 28

What is inflammatory pain caused by?

Answer 28

tissue damage

Question 29

What is neuropathic pain caused by?

Answer 29

damage to neurons

Question 30

What is the role of the vestibular system? (inner ear)

Answer 30

meaintains balance and posture

Question 31

What does vestibular information work with to maintain balance and posture?

Answer 31

- proprioception (sensing body postition) - Kinesthesia (sensing body movement)

Question 32

What are the 5 key principles of preception in Gestalt psychology?

Answer 32

- figure-ground - proximity - similarity - continuity - closure

Question 33

Olfactory: what is the mucus layer?

Answer 33

a layer of snot rgat traps smell particles

Question 34

Olfactory: what are olfactory hairs?

Answer 34

extensions of the receptor cells that reiceve the chemicals

Question 35

what is the role of the olfactory filments?

Answer 35

sends the messages to the olfactory bulb

Question 36

What is the role of the olfactory bulb?

Answer 36

collects signals and relays them to the tract

Question 37

What is the role of the olfactory tract?

Answer 37

gathers the signals and tells the brain there is a stink in the air

Question 38

Olfactory: what is the role of the limbic system?

Answer 38

interprets info and tarnslates it for the brain

Question 39

What is the role of the gustatory hairs?

Answer 39

stimulation of hese long microvilli sends a signal to larger cells

Question 40

What is the role of the gustatory cells?

Answer 40

signals from the hairs send a wave of depolarization to sensory nerves

Question 41

What is the role of the sensory nerves?

Answer 41

cranial nerves 7,9 + 10 are stimulated

Question 42

What is the role of saliva?

Answer 42

breaks down the material as you chew

Question 43

What are the 5 different kinds of taste?

Answer 43

- sweet - sour - salty - bitter - umami

Question 44

What is the role of the encapsulated nerve endings?

Answer 44

repsond to different vibration frequencies and pressures, project to the spinal cord via A-beta sensory afferents (fast)

Question 45

What is the role of the un-encapsulated nerve endings?

Answer 45

repsond to temp, pressure and pain, project to the spinal cord via the A-delta and C sensory afferent (slow)

Question 46

What are the somatosensory receptive fields?

Answer 46

a portion f skin that, when stimulated, activates a somatosensory neuron

Question 47

What is the role of the thalamus in the somatosensory system?

Answer 47

somatosensory input from the dorsal column- medial lemniscal and trigeminal pathways pass through the ventral posterior nuclei of the thalamus and the project to the somatosenssory cortex.

Question 48

What are the 2 key features of the sensory and motor homunculi?

Answer 48

- somatotopy - cortical magnification

Question 49

What is somatotopy?

Answer 49

adjacent parts of skin surface are represented by adjacent parts of the cortex

Question 50

What is cortical magnification?

Answer 50

proportion of cortex devoted to body parts is related to their sensitiity/ functional importance

Question 51

Where in the brain is the superior colliculus?

Answer 51

midbrain

Question 52

What is the role of the superior colliculus?

Answer 52

contains neurons that respond to visual, audiatory and tactile stimulus, merges info from different sensory modalities to enable efficient reactions

Question 53

What is the temporal and spacial rule?

Answer 53

when signals arrive at the same time from the same location

Question 54

What is the McGurk effect?

Answer 54

demonstartes that visual speech can influence preception also when the acoustic signal is clear