Cortex Somatosensory Flashcards Preview

Neuroscience > Cortex Somatosensory > Flashcards

Flashcards in Cortex Somatosensory Deck (51):
1

What are the 6 layers of the cortex from outer to inner?

- Molecular
- External granular
- External pyramidal
- Internal granular
- Internal pyramidal
- Multiform

2

What types of fibers enter the external granular layer?

Long associative fibers

3

What types of fibers are found throughout the external granular layer?

- Short associative fibers

4

What types of fibers exit the external pyramidal layer?

Long associative

5

What types of fibers are found within the external pyramidal layer?

- Short associative
- Commissural

6

What types of fibers are found within the internal granular layer?

- Corticalpetal (go everywhere)
- Thalamocortical radiations

7

What types are found in the internal pyramidal layer?

Corticofugal fibers from:
- Striatum
- Brainstem
- Spinal cord

8

What layer has reciprocal connections to the thalamus?

Multiform

9

What gyrus makes up the Sensory cortex?

Postcentral gyrus

10

Is the sensory cortex hetero or homotypical?

Hetero

11

What are the 4 portions of the sensory cortex from anterior to posterior

3a, 3b, 1, 2

12

From what structure do 3a and 3b receive most of their projections?

Thalamus

13

What types of fibers does 3b receive? What sensory information do they carry?

Fast and slow adapting cutaneous receptors (texture, and size and shape of objects)

14

What types of fibers does 3a receive?

Proprioception

15

What areas do 3a and 3b project to?

Areas 1 and 2

16

What are the 5 largest areas of the sensory homunculus?

- Lips
- Tongue
- Feet
- Hand
- Face

17

How are individual modalities of S1 arranged within the cortex?

In columns (one for fast adapting, one for slow adapting fibers)

18

What are the 2 pathways of S1?

- What
- Where

19

Which pathway sends information to S2?

What

20

Which pathway works with the posterior parietal cortex?

Where

21

What structures does the What pathway connect with?

- Insula
- Parietal operculum
- S2

22

What areas make up the Where pathway?

5, 6, 7

23

Which pathway can recognize objects with visual aid?

What

24

Which pathway can determine where an object is in space?

Where

25

What will a lesion to 3b cause?

Loss of discrimination of texture, shape, and size

26

What will a lesion to 1 cause?

Inability to assess texture

27

What will a lesion to 2 cause?

Inability to assess shape and size

28

Why are pain, temperature, and crude touch not affected by a lesion to S1?

The LSTT negates the loss

29

How does S2 connect with S1?

Via the Treanscallosal Connection

30

What are the 5 functions of S2?

- Bimanual coordination
- Rapid transfer of acquired tactile skills
- Texture and shape discrimination
- Acute pain
- Localizes

31

What 2 effects will a lesion of S2 cause?

- Severe impairment of discernment of shape and texture
- Inability to learn tactile discrimination based on shape

32

Is the associative somatosensory cortex homotypical or heterotypical?

Homotypical (most common)

33

What complex plays a large role in the Associative cortex?

Posterior parietal complex

34

What 3 functions does the posterior parietal complex perform?

- Perception and intrepretation of spatial relationships
- Accurate body image
- Learning tasks related to coordination of bod yin psace

35

What function does Area 5 perform in the Associative cortex?

Integrates tractile info from mechanoreceptors in skin and prorioception from muscles and joints

36

What sensory information does area 7 of the associative cortex integrate?

- Vision
- Tactile information
- Propriocpetive information

Aligns body coordinate system with the environment

37

What 5 strange disorders result from lesions to the Associative cortex?

- Tactile agnosia
- Astereognosia
- Amorphognosia
- Ahylognosia
- Neglect syndrome

38

What is tactile agnosia?

- Can't recognize objects, but can describe them through touch

39

What is astereognosia?

Can't recognize object through feel

40

What is amorphognosia?

Can't recognize object through form

41

What is ahylognosia?

Can't feel: weight, texture, or density

42

What is neglect syndrome?

- Ignore portion of body or world

43

Is the motor cortex granular or agranular?

Agranular

44

Is the motor cortex heterotypical or homotypical?

Heterotypical

45

What functions does the insula perform?

- Determines quality and intensity of stimulus
- Affective aspects of pain
- Deals with homeostasis

46

What is the function of the Anterior Cingulate Cortex?

- Generates/ controls emotions
- Unsettling/ unpleasant pain activate

47

What 2 structures make up the parabrachial nucleus?

- Amygdala
- Hypothalamus

48

Where is the allocortex found?

Deep temporal lobe

49

How many layers is the allocortex?

3

50

What are the 3 layers of the allocortex?

- Molecular
- Pyramidal/ granule
- Polymorphic

51

What 4 structures make up the allocortex?

- Subthalamus
- Hippocampus
- Dentate gyrus
- Parahypocampal gyrus