Corticol Organisation And Function

Question 1

what is the cerebral cortex and where is it found?

Answer 1

Surface of brain covers it all

Question 2

Organisation of cerebral cortex

Answer 2

organised into lobes → frontal, temporal x2, parietal x2, occipital
Further organized unto cortical layers and columns

Question 3

What are folds called

Answer 3

gyri (ridges) and sulci (grooves)

Question 4

define cytoarchitecture?

Answer 4

e.g. cell size, spacing/packing density and layering

Question 5

Frontal lobe

Answer 5

regulate + initiate motor function

language

cognitive functions e.g. planning

memory

attention

Question 6

Parietal lobe

Answer 6

Sensation
Sensory aspects of language
Spatial orientation
Self perception

Question 7

Occipital and temporal lobe

Answer 7

Visual info
Temporal-hearing emotions and memory

Question 8

what does the limbic lobe include?

Answer 8

amygdala, hippocampus, cingulate gyrus, mamillary body

Question 9

What’s Limbic lobe concerned with

Answer 9

Memory
Emotion
Motivation
Learning

Question 10

Insular cortex

Answer 10

In lateral fissure
Concerned with visceral sensation autonomic control and interoreception

Question 11

grey matter vs white matter → what is each made of, which is the outer layer?

Answer 11

grey matter on the outside

grey = neuronal cell bodies, glial cells

white = myelinated axons arranged in tracts

Question 12

three types of white matter tracts?

Answer 12

• association fibresconnect areas in the same hemisphere
• commissural fibresconnect homologous structures in opposite hemispheres
• projection fibresconnect cortex with lower brain structures

Question 13

association fibres split into which categories?

Answer 13

Short and long fibres

Question 14

main association fibres → what do they connect?

Answer 14

• superior longitudinal fasciculusfrontal ↔ occipital
• arcuate fasciculusfrontal ↔ temporal
• inferior longitudinal fasciculustemporal ↔ occipital
• uncinate fasciculus (under arcuate and shorter)anterior frontal ↔ temporal

Question 15

main commissural fibres?

Answer 15

corpus callosum

anterior commissure

Question 16

two types of projection fibres for projection

Answer 16

afferent (towards cortex) and efferent (away from cortex)

• internal capsule → between thalamus and basal ganglia

Question 17

where do projection fibres converge?

Answer 17

internal capsule → between thalamus and basal ganglia

Question 18

difference between primary and secondary/association cortices?

Answer 18

predictable vs less predictable function

topographical organisation present vs absent

left-right symmetry present vs weak/absent

• premotor area (more lateral) and supplementary area (more medial) → both anterior

Question 19

association cortices for frontal lobe

Answer 19

premotor area (more lateral) and supplementary area (more medial) → both anterior

Question 20

what are these three involved in?

Answer 20

primary controls fine voluntary movement, provides descending signals to execute these

supplementary area involved in planning internally cued complex movements

pre-motor area involved in planning externally cued complex movements

Question 21

where is the primary somatosensory cortex and what is its secondary cortex?

Answer 21

found posterior to central sulcus → postcentral gyrus, posterior to that is somatosensory association

Question 22

difference in function between these two? Parietal

Answer 22

primary processes somatic sensations from receptors, association interprets eg fine touch vibration two point discrimination proprioreception and pain and tempsignificance of sensory info e.g. recognising object in hand, awareness of self and personal space

Question 23

occipital lobe → primary visual vs visual association functions?

Answer 23

primary processes visual stimuli, visual association gives meaning and interpretation

Question 24

temporal lobe → primary auditory vs auditory association functions?

Answer 24

processes stimuli / gives meaning and interpretation

Question 25

main other association areas?

Answer 25

prefrontal cortex, Broca’s area, Wernicke’s area

Question 26

difference between Broca and Wernicke?

Answer 26

Broca = production of language, Wernicke = understanding of language

lesions cause expressive aphasia / receptive aphasia

Question 27

function after lesion impairment → examples?

Answer 27

• frontalbehavioural change
• parietalcontralateral neglect, lack of awareness of self/personal space on one side
• temporalloss of ability to form new memories, recognise stuff
• occipitalblindness for primary / deficits in interpretation for association e.g. prosopagnosia → inability to recognise faces

Broca’s area
Expressive aphasia poor production of speech

Wernickes
Receptive aphasia poor comprehension of speech production is fine

Question 28

what does a PET scan show?

Answer 28

positron emission tomography → blood flow directly to a brain region

Question 29

what does an fMRI scan show?

Answer 29

functional magnetic resonance imaging → amount of blood oxygen in a brain region

Question 30

what do MEG and EEGs show?

Answer 30

magnetoencephalography & electroencephalography → event-related magnetic/electrical potentials

Question 31

what is TMS and what does it do?

Answer 31

transcranial magnetic stimulation → helps stimulate the brain and assess functional integrity of circuits, investigate function of a brain area

Question 32

what is tDCS?

Answer 32

transcranial direct current stimulation → direct current over the scalp to increase/decrease neuronal firing rates

Question 33

what is DTI and what is it useful for?

Answer 33

diffusion tensor imaging → assess structure based on diffusion of water molecules

Question 34

Prefrontal cortex

Answer 34

Attention
Adjusting social behaviour
Planning
Personality expression
Decision making