Task 4 Flashcards
(75 cards)
1
Q
What does the cortex together with the deep nuclei build up on ?
A
- gray matter of the forebrain.
2
Q
Why do we have gyri and sulci ?
A
- Cortical surface area needs to be increased. (because we gained over the last decades to much knowledge)
- Therefore, the cortex is highly folded, forming gyri and sulci.
- gyri = Berg
- sulci= tal
3
Q
How is each area connected ?
A
Via fibers:
- association fibers
- commisural fibers
- Pfrojection fibers
4
Q
How is the neocortex organized ?
A
- 6 layers
- Each layer contains different cells (each layer has predominating cells)
- Phylogenetically most recent part
5
Q
How is the older cortex (allocortex) organized ?
A
- 3 layers
- Main parts are the archiocortex and paleocortex
- Phylogenetically oldest part
6
Q
What is meant by the acrchiocortex ?
A
- Hippocampus
7
Q
What is meant by the plaeocortex ?
A
- olfactory bulb
8
Q
What neuron is located in layer 3 and 5 and what is it major function ?
A
- Pyramidal neurons
- Fuction: mainly output cell of the cortex
9
Q
What neuron is located in layer 2 and 4 and what is it major function ?
A
- Granular neurons
- Function: mainly interneurons
10
Q
How is layer 1 also called and what is major function ?
A
- molecular layer
- Function: neuronal processes
11
Q
How is layer 6 also called and what is major function ?
A
- multiform layer
- Function: output neurons
12
Q
How are cells in layer distributed ?
A
- different areas have different cells distribution
- all depending on areas
13
Q
How are cells distributed in the primary motor cortex ? How is the cortex also called ?
A
- agranular cortex
- not many granular neurons more pyramidal
14
Q
How are cells distributed in the primary sensory cortex ? How is the cortex also called ?
A
- granular cortex
- many granular neurons but less pyramidal
15
Q
What is so sepcial about each functional unit ?
A
- Also called cortical column
- Those are the vertical layer
- 2 main parts are ocular dominance collumns and orientation collumns
- have specific function
16
Q
What was the major finding of Brodmann ?
A
- found areas with different histological organisations
17
Q
What was the major finding of penfield ?
A
- that the different areas from Brodman correlate with functionally different areas
18
Q
What is the major defintion of fibers ?
A
- Relay information to and from specific areas of the brain
19
Q
What is the major function of the association fibers ?
A
- interconnect cortical areas within a hemisphere
20
Q
What is the major function of short association fibers ?
A
- connect neighbour or close by gyri
21
Q
What is the function of long association fibers ?
A
- connect more distant areas
- via four major fibers
22
Q
Name all four long association fibers ?
A
- Superior longitudinal fasciculus
- Inferior occipitofrontal fasciculus
- Superior occipitofrontal fasciculus
- Cingulum
23
Q
Which ares does the Superior longitudinal fasciculus connect ?
A
- frontal, parietal, temporal and occipital lobes
24
Q
What subtypes of fibers does the Superior longitudinal fasciculus contain and what is it function ?
A
- Arcuate fasciculus
- Function: connects the two major language areas
25
Which ares does the Inferior occipitalfrontal fasciculus connect ?
- frontal, temporal and occipital lobes
26
What subtypes of fibers does the inferior occipitalfrontal fasciculus contain and what is it function ?
- Uncinate fasciculus
| - Function: connects frontal and temporal lobe
27
Which areas does the Superior occipitalfrontal fasciculus connect ?
- Location: superior to corpus collosum
| - connection: interconnects frontal, parietal occipital lobes
28
Which ares does the cingulum connect ?
- Location: within limbic lobe
| - connects areas of limbic system/cortex
29
What is the major function of the commissural fibers ?
- connection of similar functional areas between the hemispheres
30
Which ares contains the largest amount of commissural fibers ?
1. corpus callosum
2. Also anterior commissure
2. Also posterior commisure
31
What is the major function of the corpus callosum ?
- connects the two parietal lobes and the posterior parts of the frontal lobes with each other
32
In which major structures is the corpus callosum divided ?
1. Genu
2. Body
3. Splenium
33
What does the body connect ?
- connect parietal lobes with posterior parts of frontal lobe
34
What does the genum connect ?
- connect frontal lobe
35
What does the splenium connect ?
- connect occipital + posterior temporal lobes
36
What is the major function of the projection fibers ?
- information travel to and from the cortex
| - toor from the thalamus basal ganglia, the brainstem, or spinal cord
37
How does the projection fibers work in depth ?
- Converge from corona radiata (al parts of the cortex which contain projection fibres ) in compact bundle called internal capsule !!
38
What is meant by the holistic concept ?
- emphasized the role of the entire cerebral cortex in the execution of any brain function
39
What is meant by the localization paradigm ?
- convinced that these functions are localizable to specific cortical areas
40
According to Brodamanns map, out of how many cytoarchitectonic areas does our cortex exist of ?
- 43 for human and 30 cytoarchitectonic areas for monkeys
41
According to Brodamanns map, out of how many areas in general does our brain exist of ?
- 1 and 52
42
Which areas can not be identified at the cortex and which areas are those ?
- 12-16 and 48-51 not
| - olfactory bulmb, limbic system insular cortices
43
What were back then the problems with Brodmans map ?
- same species had differentail variation in the architectonic structure of areas
- Lack of observer independency, reproducibility & objectivity
- Lack of data on inter-subject variability
- did not contain data on the intrasulcal surface
44
Why was brodmanns map still such a succes ?
- new neuroimaging techniques supported his map (DTI and fibre tracking)
- translate his map from 2D to 3D
45
What is the function of anterogarde and retrograde tracing ?
- allow the detailed descriptions of neuronal projections from a single neuron or a defined population of neurons to their various targets throughout the nervous system.
- it creats a map
- much of neuroanatomy mapping is based on that
46
What is meant by retrograde transport (Inward transport)
- from synapse to soma
| - mediated (controlled) by the motor protein dynein
47
What is meant by anterograde transport (outward transport)
- from sona to synapse
| - mediated or controlled by kinesin
48
Which kind of track are both of the transport pathway following
- microtubules trac
49
How is the general process for anterorgrade and retrograde transport called ?
- AXOPLASMIC TRANSPORT
50
Define AXOPLASMIC TRANSPORT:
- essential for growth and survival
| - movement of (mitochondria), lipids, proteins, vesicles and other parts of the cell between the soma to the synapses
51
What are the advantaged of tracing mapping ?
- Learn specifically where the input to a field comes from & where it sends its output to
52
How does tracing maping work ?
- direct physical injection of various visualizable tracer moleculesin into the brain
53
What are the disadvantages of tracing ?
- injection never matches field of interest
| - substances spreads to close by fields/areas
54
What is the main function of the cerebral cortex ?
Control and information processor
55
What does the the cerbral cortex exist of ?
- cell bodies and capillaries
56
Why is it difficult to study the cerbel cortex ?
- because it has a high complexity
| - High structural variability across individuals
57
What is the structure of the internal capsule ?
- V shaped
- posterior limb
and anterior limb
58
What was the first case of mapping neurological imaging ?
- Phinease gage, broca and epilepsy
| - Afterwards experimental evidence
59
How were brodmanns problems solved ?
- via the Talairach transformation
| - via the cortex surface based approach or also called cortex-based alignment
60
How did the talairach transformation solve the problems from brodmann ?
- finding outer boundaries of the cerebrum
- finding out the anterior and posterior commissure
- rescale subvolumes
according to a specific brain
61
How did the cortex-based alignment solve the problems from brodmann ?
- it created a 2D picture of the entire cortex
62
What is the first principel of the large scale functional organisation ?
- The brain has a non-random small-world organisation
- tries to minimiez wiring coast via modular organization
- Explains random world via Nodes hubs and edges
63
What is the second principel of the large scale functional organisation ?
- The brain has a strong interhemispheric connectivity between homotopic regions
64
What is the third principel of the large scale functional organisation ?
- The brain is Intrinsically organised into multiple coherent networks
- 14 in total
- specific region are active together during differnt task (bilateraly)
65
What is the fourth principel of the large scale functional organisation ?
- The brain also shows during certain kinds of cognition deactivtaion of certain patterns to save resources and to not create conflict
- > Antagonistic nature -> bottlenecks
66
What is the fifth principel of the large scale functional organisation ?
- The brain has a default-mode network
- That means even if we do not engage in any kind of task our brain works
- It works on memories and
important self-referential information processing
- mostly seen in Posterior cingulate cortex & medial prefrontal cortex
67
What is meant with modular organization ?
- a cluster of nodes which all together have a specific function
68
What is meant by Nodes ?
- a singel node represents one part of a module
| - basic structure
69
What is meant by hubs ?
- same as a node but connects to a lot of other nodes becuase a lot of edges are linked towards it
70
What is meant by edges ?
- those are the transmissions between two nodes
71
What is meant by homotopic and heterogeneous region ?
- Homotopic = connection between identical structures in different hemisphere
- heterogeneous region = a connection between two different region across both hemisphere
72
What kind of connectivity does the left hemisphere prefer ?
- connectivity, particularly for cortical regions involved in language
- refereed as lateralisatiom bias
73
What kind of connectivity does the right hemisphere prefer ?
- connectivity with visuospatial and attentional processing
| - refereed as lateralisatiom bias
74
What does intrahemispheric connectivity mean ?
- connectivity in same hemisphere
75
What does interhemispheric connectivity
- connectvity between two hemisphere
