Week 9: Vision & Audition

Question 1

What is sensation?

Answer 1

Matter in which our sense organs receive information from the environment

detection of a stimulus, comes in from the outside

Question 2

What is perception?

Answer 2

manner by which people select, organise and interpret sensations

understanding a stimulus based on what we already know

Question 3

What is transduction?

Answer 3

manner by which physical energy is converted into sensory neural impulses

Question 4

What is the neocortex?

Answer 4

thin sheet of cells covering the brain organised into 6 stereotypical layers

Question 5

What are the 6 layers of neocortex?

Answer 5

1-3 is cortico-cortical (interoffice mail)
4 - thalamo-cortical (inbox)
5- cortico-fugal
6- cortico-thalamic -which are both the outbox

Question 6

What lobe is responsible for vision?

Answer 6

occipital

Question 7

what lobe is responsible for audition?

Answer 7

temporal

Question 8

Why is the thalamus a major sensory region of cerebral cortex?

Answer 8

responsible for relaying all sensory information apart from smell

it is the gatway to the cortex

Question 9

what is the primary pathway for vision?

Answer 9

retina - optic nerve - optic chiasm - thalamus - occipital lobe

Question 10

what is the primary pathway for audition?

Answer 10

auditory nerve - cochlear nuclei - superior olivary nuclei - inferior colliculus - medial geniculate - auditory cortex

• geniculate is the same as thalamus

Question 11

what are soundwaves?

Answer 11

hearing occurs via sound waves which results from the rapid changes in air pressure caused by vibrating objects

Question 12

what is pitch?

Answer 12

frequency of vibration measured in hertz

Question 13

what is loudness?

Answer 13

function of sound wave intensity; amplitude

Question 14

what is timbre?

Answer 14

provides information about nature or complexity of the sound

Question 15

where are the primary auditory receptors located?

Answer 15

cochlear (similar to the retina)

tiny hair cells convert sound energy to neural impulses and send them along to primary auditory cortex

Question 16

what does the central auditory system consist of?

Answer 16

cochlea, superior olives, colliculi, thalamus and primary auditory cortex

Question 17

What is the pinna?

Answer 17

external ear

Question 18

what is the Tympanic membrane (TM)?

Answer 18

eardrum

Question 19

What is the middle ear?

Answer 19

hollow region that contains ossicles between TM and cochlear

Question 20

what are the ossicles?

Answer 20

middle ear bones which consist of:

• malleus
• incus
• stapes

*sound waves make these bones move around

Question 21

what is the cochlea?

Answer 21

snail-shaped structure of the inner ear which contains the Organ of Corti

Question 22

what is the organ of corti?

Answer 22

sensory organ for the auditory system contained within cochlea

Basilar membrane, hair cells and tectorial membrane are contained within organ

Question 23

what is the oval window?

Answer 23

opening door of cochlea where stapes is located

Question 24

what is the round window?

Answer 24

opening in the cochlea

Question 25

what is the tectorial membrane?

Answer 25

rests on the hair cells

Question 26

what is the basilar membrane?

Answer 26

has base and apex natural sounds excite cells across membrane low frequency sounds excite cells near apex high frequency sounds excite cells near base

Question 27

how is an action potential triggered in the auditory nerve?

Answer 27

stimulation of the hair cells trigger AP minimum movement needed is 1-100 picometres to generate sound

Question 28

What is anterior pathway (PFC) more involved in?

Answer 28

identifying sounds - the what

Question 29

what is the posterior pathway (PPC) more involved in?

Answer 29

locating sounds - the where

Question 30

what is smell?

Answer 30

perception of odorant | does not pass through thalamus

Question 31

what is an odorant?

Answer 31

molecules that give off smell bind to receptors in olfactory cilia

Question 32

what is the golmeruli?

Answer 32

clusters of convergent olfactory sensory neurons

Question 33

where are the receptors for taste located?

Answer 33

in the tongue and oral cavity, in clusters called taste buds

Question 34

what are the 4 primary tastes?

Answer 34

sweet, salty, sour and bitter *5th is savory

Question 35

which 2 tastes do not have receptors?

Answer 35

salty and sour they merely act on ion channels

Question 36

what is the gustation pathway?

Answer 36

solitary tract - thalamus - cortex

Question 37

what are the 3 separate interacting systems of touch?

Answer 37

Exteroceptive - external stimuli Proprioceptive - body position Interoceptive - internal body conditions

Question 38

What are the 5 touch receptors?

Answer 38

``` Merke disks - regular touch Meissner's Corpuscles - light touch Pacinian Corpuscles - deep pressure Ruffini Corpuscles - temperature Nociceptors - pain ```

Question 39

what are the 2 major touch pathways?

Answer 39

Dorsal colum medial leniscus system - mainly touch and proprioception Anterolateral system - mainly pain and temperature

Question 40

what is hue?

Answer 40

wavelength

Question 41

what is brightness?

Answer 41

intensity

Question 42

what is saturation?

Answer 42

purity

Question 43

what are the receptors in the visual system?

Answer 43

rods and cones located at the back of the eyeball

Question 44

what are cones?

Answer 44

For phototopic or daytime vision and are the only receptors found in the fovea Used for high acuity colour info in good lighting

Question 45

what are rods?

Answer 45

For scotopic or night time vision Have high sensitivity, low acuity vision in dim light lacks detail and colour info

Question 46

how does visual processing occur in occipital lobe?

Answer 46

retina - lateral geniculate nucleus of the thalamus - extra striate cortex

Question 47

what is the MT in charge of?

Answer 47

motion | if damaged, you can not see motion anymore but can see when still

Question 48

Which structure provides representation of multi-sensory space?

Answer 48

superior colliculus

Question 49

what are the 2 types of deafness

Answer 49

Conductive - damage to ossicles | Nerve - damage to cochlea

Question 50

what is anosmia?

Answer 50

inability to smell

Question 51

what is ageusia?

Answer 51

inability to taste

Question 52

what is asterognosia?

Answer 52

inability to recognise objects by touch

Question 53

what is asomatognosia?

Answer 53

failure to recognise parts of ones own body

Question 54

what is achromatopsia?

Answer 54

loss of colour vision

Question 55

what is akinetopsia?

Answer 55

selective loss of motion perception

Question 56

what is neglect syndrome?

Answer 56

involuntary failure to attend to sensory stimuli presented in the side of space opposite to the site of brain injury

Question 57

What is scotomas?

Answer 57

discrete regions of blindness