lecture 6

Question 1

brain development - location specificity

Answer 1

what a neutron does depends on its input and therefore it depends on the place/location in the network

Question 2

to produce neurons a

Answer 2

precursor structure must be in place - intermediate cell before they become differentiated

Question 3

neurons and glia cells develop from

Answer 3

neural stem cells at the ventricular inner surface and travel to their eventual destination

Question 4

steps of Brain development

Answer 4

1- cell proliferation
2-cell migration
3-connecting cells

Question 5

cell proliferation

Answer 5

undifferentiated stem cells grows an extension to the surface
cell nucleus moves UP and duplicates its DNA
nucleus moves back DOWN
cell retracts extension and divides into two

Question 6

cells behave differently depending on

Answer 6

whether the stem cell has divided vertically or horizontally

Question 7

vertical split

Answer 7

both daughter cells repeat the process

Question 8

horizontal split

Answer 8

one daughter cell repeats the process other moves away and not divide again

Question 9

cell migration

Answer 9

different cell types gave different places of origin

Question 10

pyramidal neurons and astrocytes originate

Answer 10

from dorsal areas and migrate vertically

Question 11

inhibitory interneurons and oligodendroglia originate

Answer 11

from more ventral areas and migrate laterally

Question 12

cortex is not

Answer 12

a single homogenous sheet

organised in a structured way

Question 13

radial glia cells

Answer 13

in the ventricular zone they extend thin processes towards the surface in an ordered pattern

Question 14

ventricular zone is a

Answer 14

photomap if the cortex

Question 15

connecting cells what 3 problems must be solved

Answer 15

find the right direction
find the right target structure
find the right target cells inside target structure

Question 16

find the right direction

Answer 16

right hand sensed and controlled by left hemisphere

right half of the visual field represented in left hemisphere

Question 17

growing axons are guided by

Answer 17

chemical signals in the environment

Question 18

depending on a neurons location it has

Answer 18

different chemical affinities - different likes and dislikes

Question 19

find the right target structure

Answer 19

chemo affinity hypothesis - axons from a specific source structure are only attracted to chemicals from a specific target structure

Question 20

find the right target cell

Answer 20

maps are important for action control

Question 21

general strategy

Answer 21

use it or lose it

initially , axons synapse with cells in their target structure

Question 22

pruning

Answer 22

useful synapse are maintained

useless ones disappear

Question 23

what is a useful synapse

Answer 23

links two neurons that most of the time are either both active or both silent
correlated activity

Question 24

useless

Answer 24

links two neurons that are rarely both active and silent

uncorrelated neural activity

Question 25

hebbian modification

Answer 25

if activity of pre and post synaptic cell is highly correlated synapses strengthen