Lecture 2

Question 1

List the four (five) lobes of the cerebral cortex, and state the major functions of each lobe.

Answer 1

frontal--prefrontal associat
parietal
temporal
occipital
insular

Question 2

Label a diagram to show the location of key cortical regions

Answer 2

ye

Question 3

Map sensory and motor function for the various regions of the body to the cortical “homunculus”; and describe the main arterial supply to each region of the motor and sensory homunculus.

Answer 3

ye

Question 4

Describe how the different cortical regions work together

Answer 4

ye

Question 5

study slide 3

Answer 5

ye

Question 6

study slide 4

Answer 6

ye

Question 7

describe the frontal lobe

Answer 7

frontal–prefrontal association cortex, develops until you’re 25; contains primary motor cortex; the “go” lobe–>tells you to move;
Surrounded by areas of “higher motor function”make the movement from the PMC more complex, can inhibit movement
Motor planning, take in the information and make movement based on that

• Broca’s speech area (motor, expressive)
• premotor/ supplementary
  motor areas

frontal eye fields (scanning visual field)e.g. loud noise, eyes go right to the source of the noise automatically
May have implications in autism

• orbital cortex, olfactory tract

Question 8

study pic on slie 7

Answer 8

ye

Question 9

describe the parietal lobe/cortex

Answer 9

• primary somatosensory sensory cortex
  
  • secondary and tertiary somatosensory cortices
  • connection between receptive and expressive speech areas
    
    • e.g. asked question respond

also involved in trackin movements (smooth pursuit); if someone lacks smooth pursiot they had a stroke in this area; also motor and sensory defects

Question 10

describe the occipital lobe

Answer 10

• visual cortices: primary (17)—see one dimension, secondary (18)—see a few dimension, tertiary (19)—see 3D, estimate height, width, etc
• dorsal areas = where? (analysis of motions and spatial relations). May not be able to identify where objects are
• ventral areas = what? (analysis of form and colour) Can’t recognize what an object is or who someone is

Question 11

study slide 8 and 9 pics

Answer 11

ye

Question 12

describe the temporal lobe

Answer 12

contains Wernicke’s areas;
W’s area: understanding of speech and written langugae; sensory aspect;
arcuate fasciculus between WA and BA–>very big connections a very vulnerable spot in the brain
If someone says t repeat something and you can’tsomething wrong with the area of connection between wernicke and broca’s connections
Hard to name things (e.g. can you get me that…um…um…etc)

also functions in memory; memory (medial portions, including hippocampus) , facial/ color recognition
Why is memory not association (higher function)? –>emotion associated with memory (survival); need to remember who your parents are, what animal tried to eat you, etc
Not unique to humans

Question 13

describe the insula

Answer 13

primary auditory cortex
taste (primary gustatory nucleus)
other visceral sensory—e.g. going “oh crap” when you realize you forgot to plug your car in overnight
social, emotions, limbic

tightly linked to vomiting centre

Question 14

4.1 Define, and label a diagram to show the location of key cortical regions, including motor, sensory,
unimodal, and multimodal regions: (review: be able to label the four (five) lobes of the cerebral
cortex, describe the major functions or each lobe, and describe the major source of blood supply for each lobe)

a. sagittal and lateral fissures, central (Rolandic) sulcus
b. motor regions:
- primary motor cortex (precentral gyrus)
- unimodal motor regions: premotor & supplementary motor regions (paracentral lobule);
Broca’s area
c. sensory regions:
- primary somatosensory (postcentral gyrus), primary auditory, & primary visual cortices
- unimodal association areas (somatosensory, auditory, visual); Wernicke’s area

d. multimodal association cortices: cingulate gyrus, prefrontal cortex

Answer 14

ye

Question 15

Although there is some individual variability, the human brain has some characteristic “lumps and bumps”, or what are properly called gyri (elevations) and sulci (depressions).

These sulci and gyri serve as important landmarks and boundaries for the localization of very different types of cortical functions, even within a given cortical lobe.

Answer 15

ye

Question 16

what does the central sulcus separate?

Answer 16

frontal and parietal lobes; aka ROLANDIC FISSURE

Question 17

what does the lateral sulcus separate?

Answer 17

frontal and parietal lobes from temporal lobes; AKA SYLVIAN FISSURE

Question 18

what does a sulcus often represent?

Answer 18

a significant separation of cortical function:

eg: the central sulcus separates the primary motor cortex (in the frontal cortex) from the primary somatosensory cortex (in the parietal cortex)

Question 19

what does a Rolandic fissue present as?

Answer 19

Kids that have seizures may have Rolandic epilepsy–>means seizures along the Rolandic fissue; distinct motor and sensory deficits; symptoms = lip smacking, hypersalivation (oral cavity affected by these seizures!!)

Question 20

study slide 17

Answer 20

ye

Question 21

study slide 18

Answer 21

ye

Question 22

study slide 19

Answer 22

ye

Question 23

broca’s area = expressive language; wernicke’s area = understand what was said with you

Answer 23

ye

Question 24

what is the primary motor cortex?

Answer 24

a portion of the brain in the precentral gyrus which contains large excitatory neurons (UMN) which project to brainstem and spinal cord to execute movement on CONTRALATERAL side of body
contralateral = deccasates at brain stem (?) and controls the opposite site of the body

Question 25

what are the unimodal association cortices in the frontal lobe?

Answer 25

- premotor and supplementary motor regions (motor planning) | - Broca’s area (expressive language)

Question 26

what are the multimodal association cortices in the frontal lobe?

Answer 26

- cingulate gyrus (medial surface) – limbic - error detector limbic systems usually medial and ventral - prefrontal cortex (lateral surface) – judgement, abstract reasoning, cognition, eye movementstructure that makes you as an adult; youths have a less developed preofrontal cortex; development complete at 25 Two or more purposes

Question 27

study slide 20& 21

Answer 27

ye

Question 28

what is the primary somatosensory cortex?

Answer 28

- located in the postcentral gyrus (parietal lobe) - contains many small neurons which receives different types of somatosensory information from the CONTRALATERAL side of the body

Question 29

what are the uni- and multimodal cortices in the parietal lobe?

Answer 29

Unimodal & multimodal association somatosensory cortices: - processes higher somatosensory information - no specific regions of note, except that damage to these cortices can cause neglect Unimodal & multimodal areas are less defined

Question 30

study slide 23

Answer 30

ye

Question 31

what is the primary auditory cortex?

Answer 31

in temporal lobe;

Question 32

what is wernicke's area?

Answer 32

the area for processing the receptive aspects of speech – sends information to Broca’s area via a pathway called the arcuate fasciculus surrounds primary auditory cortex

Question 33

the primary visual cortex in occipital lobe

Answer 33

ye

Question 34

study slide 25

Answer 34

ye

Question 35

where is the cingulate gyrus located?

Answer 35

on medial surface of the cortex

Question 36

what is the paracentral lobule?

Answer 36

involved in: Supplementary motor area: internally (not stimulus) driven movement-->planning or imagining movements Primary motor cortex: legs and feet (can’t move legs and feet from stroke/issues on medial surface/inside of brain) Primary somatosensory cortex: legs and feet located on the medial surface of the cortex

Question 37

KNOW SLIDE 28

Answer 37

YE

Question 38

Broca sits in frontal because it is associated with motor usage; Wernik. Next to primary auditory cortex

Answer 38

ye

Question 39

describe arterial supply of the brain

Answer 39

``` The ACA (anterior cerebral artery) supplies the medial portions of the cerebral cortex – legs and feet The MCA (middle cerebral artery) supplies the lateral portions of the cerebral cortex – arms, face, oral cavity ``` Broca stroke = difficulty chewing or speaking Wernicke stroke = may not be able to understanding you and your instructionsmay want power of attourney

Question 40

Describe: - the role of primary, unimodal association, and multimodal association cortices in the processing of information - the role played by associational and commissural fibers in the cerebral hemisphere

Answer 40

primary cortices are ground zero for the reception or the production of information (i.e., sensory or motor information); unimodal (aka secondary) cortices process "higher" information for one specific modality (such as planning simple motor behaviors, processing specific aspects of a sensation, etc.); multimodal association cortices: process information across all modalities (motor, sensory, limbic, cognitive)--aka “tertiary cortices”

Question 41

study slide 39 & 40

Answer 41

ye

Question 42

describe the unimodal sensory cortex

Answer 42

-receives its predominant input from primary sensory cortex of specific modality feeling sharpness of an object, cold, etc -performs higher-order sensory processing for that modality a type of ASSOCIATION cortex

Question 43

describe the unimodal motor cortex

Answer 43

- projects predominantly to primary motor cortex - formulates the motor program for complex actions involving multiple joints a type of ASSOCIATION cortex

Question 44

what are association fibres/intrahemispheral fibres for?

Answer 44

``` Single modality of sensation Responsible for: Complex aspects of sensation Compensation for missing pieces of information ``` If someone has a stroke in this visual association area will lack the brain area to fill in the missing pieces

Question 45

study slide 47

Answer 45

ye

Question 46

describe the multimodal cortex

Answer 46

- located in the frontal lobes and parieto-occipital-temporal regions - has bi-directional connections with BOTH motor and sensory association (unimodal) cortices - has bi-directional connections with other cortical regions – including limbic system - performs the highest-order mental functions - integrates abstract motor and sensory info from associational cortices; puts together with the motivational and emotional influences from the limbic system (or “limbic cortex”) can control stuff such as language processing and production (hearing, seeing, touching, and writing, and reading); arithmetic, abstract reasoning, socially appropriate behaviour, concentrating Multiple modalities of sensation Integration of: Sensory information across modalities Sensory with limbic information

Question 47

what are the limbic cortical regions and what are they responsbile for?

Answer 47

1. Cingulate gyrus; 2. orbital frontal cortex; 3. parahippocampal gyrus MAAA: Motivation Assigning emotional significance to sensory information Attending to relevant or interesting stimuli Add “emotional flavour” to cognitive activities

Question 48

what are the functions of multimodal cortices?

Answer 48

- arithmetic - abstract reasoning - language processing and production - socially appropriate behaviour - concentrating