Lecture 5 - Sensory Systems

Question 1

Whats the organisation of sensory systems ?

Answer 1

Peripheral sensory receptors
Spinal cord
Sensory thalamus
Primary sensory cortex
Unimodal assocaition cortex
Multimodal association cortex

Question 2

Whats the link between taste and smell?

Answer 2

Smelling food all helps us to taste our food

Question 3

Whats the gustatory pathway?

Answer 3

Taste buds
Going to either
- taste receptor cells or touch, pain receptors
Goes to brainstem
Goes to thalamus
The tast receptor cells goes to the taste centres of somatosensory cortex
And the touch and pain receptors go to the somatosensory cortex

Question 4

Whats area V4 for?

Answer 4

Colour processing

Question 5

Explain more about area V4?

Answer 5

Individual neurons in the V4 response to a variety of wavelengths

Question 6

What happens when you damage the V4?

Answer 6

Achromatopsia - inability to perceive colour
Patients see the world in black and white
Inability to image or remember colour
Vision otherwise normal

Question 7

Whats area V5 known for?

Answer 7

Movement perception

Question 8

Describe area V5?

Answer 8

Neurones respond to movement

Question 9

What happens when you damage area v5?

Answer 9

Akinetopsia (motion blindness) - can’t see motion smoothly

UNAFFECTED IN colour, perception, object recognition, etc
- able to judge movement of tactile or auditory stimuli

Question 10

What does the left visual field project for laterality of vision?

Answer 10

Projects bilaterally to right visual cortex

Question 11

What does the right visual field project for laterality of vision?

Answer 11

Bilaterally to left visual cortex

Question 12

Whats area v3?

Answer 12

Building a visual represention of the object

Question 13

Whats area v2?

Answer 13

Virtual vision

Question 14

Whats the ventral stream?

Answer 14

Structural information and object recognition

Question 15

Whats the dorsal stream?

Answer 15

Spatial information

Question 16

Describe the ear cochlea?

Answer 16

Sound waves converted into vibrations in basilar membrane
Hair cells in organ of corti transduce movement of basilar membrane into electrical signal
Information is transmitted along vestibulo-cochlear nerve

Question 17

Describe the auditory processing pathway ?

Answer 17

Cochlea - ear
Cochlear nucleas - pons
Superior Oliver’s nucleus - pons
Inferior colliculus - thalamus
Medial eniculate nucleas - thalamus
Auditory cortex - cortex

Question 18

Where is processing originally thought to be in?

Answer 18

The auditory cortex

Question 19

When’s auditory discrimination possible in the absence of?

Can someone still tell sounds apart (auditory discrimination), even if something is missing or impaired?

Answer 19

Auditory cortex like direction, pitch and tunes
So
Initial processing occurs in pons and thalamus

Question 20

What does auditory cortex analyse?

Answer 20

Analyses the complex aspects of sound

Question 21

What are the two types of analysis in complex aspects of sound?

Answer 21

Dorsal stream in the partial lobe - spatial analysis
Ventral stream in the temporal lobe - component analysis

Question 22

What is localisation of sound dependent on?

Answer 22

On different characterises of a sound arriving at each ear

Question 23

Describe intensity difference?

Answer 23

Difference in intensity of sound between the two ear

Question 24

Whats latency?

Answer 24

• phase shift between the two ears
• due to slightly different distance to reach each ear

Question 25

Whats duplex theroy?

Answer 25

Sound location depends on a combination of intensity and latency

Question 26

Where is the semicircular canals found in?

Answer 26

The vestibular organ - inner ear

Question 27

What does the semicircular canals detect?

Answer 27

Detects head rotation and tilt around three axes

Question 28

Explain the direction for head movement to information being transmitted to brain?

Answer 28

Head movement Movement of endolymph Displacement of capula Stimulation of hair cells Activation of CN VIII, vestibulocochlear nerve Information transmitted to brain

Question 29

Whats the two things in the vestibular nuclei?

Answer 29

Medial and lateral which are brain stems

Question 30

Whats in the medial?

Answer 30

Neck muscles Head orientation

Question 31

Whats in the lateral ?

Answer 31

Peripheral muscles Postural muscles balance

Question 32

What causes motion sickness?

Answer 32

May be caused by a mismatch between visual information and information from the vestibular organ

Question 33

What maintains the relative position for the head?

Answer 33

As head orates, eyes move to compensate maintain the relative position

Question 34

When does vestibule-ocular reflex occur and what are they depdent on?

Answer 34

Occurs even with eyes closed Not dependent on visual input but dependent on vestibular input

Question 35

Where is auditory receptors contained in?

Answer 35

Cochlea of the ear

Question 36

Whats the lateral vestibular muscles responsible for?

Answer 36

Maintaining posture and balance

Question 37

Whats the medial vestibular nucleas responsible for?

Answer 37

Head oriention and ocular reflexes Maintain gaze during head movement

Question 38

Whats the flow for somatosensory perception?

Answer 38

Spinal cord - peripheral - sensory receptors Brainstem - cranial - sensory receptors Thalamus Somatosensory cortex - cingualte cortex Other cortical area

Question 39

Where is pain and temperature detected for peripheral sensory receptors?

Answer 39

Free nerve endings

Question 40

Whats the sensory receptor for touch?

Answer 40

Merkels disc Meissners corpuscle

Question 41

Whats the sensory receptor for vibrations?

Answer 41

Pacinian corpuscle

Question 42

What’s thee sensory receptor for stretch?

Answer 42

Ruffinis ending

Question 43

Whats the sensory receptor for touch and movement?

Answer 43

Hair follicle receptor

Question 44

What is nociception?

Answer 44

The perception of noxious somatosensory information

Question 45

Whats the subjective sensation evoked by nocicpetion?

Answer 45

Pain

Question 46

Whats the modulation of nocicpetion or pain?

Answer 46

Analgesia

Question 47

Whats the main sense organ for somatosensory perception?

Answer 47

The skin

Question 48

Whats the main sense organ for somatosensory perception?

Answer 48

The skin

Question 49

Where does somatosensory (touch) perception occur?

Answer 49

In somatosensory cortex - post central gyrus