Lecture 8- Neuroplasticity

Question 1

what is neuroplasticity

Answer 1

the ability of neural circuits to change through growth and reorganization happening through development

Question 2

where do stem cells align during development

Answer 2

along ventricular wall and central canal of sp cord

Question 3

what do stem cells differentiate into during development

Answer 3

glioblast and neuroblasts

Question 4

what glioblast develops before

Answer 4

radial glia which innervates the pia mater

Question 5

where does post natal neuroplasticity take place

Answer 5

migrate horizontally after climbing glial process

Question 6

what does neuroblasts develop into

Answer 6

neurites

Question 7

what are neurites

Answer 7

extension from neuron soma
defines neuron types and functions
can develop into axons

Question 8

what are types of neurites

Answer 8

multipolar- UMN, LMN and most interneurons
pseudounipolar- DRG, sensory neurons
bipolar- olfactory, visual, some interneurons

Question 9

what is the importance of polarity of neurons

Answer 9

distinctive proteins attracted to neurite tip by directional stimuli

Question 10

how does neurotrophins function as chemoattraction factors

Answer 10

different traget cells secret different neurotrophins- cytokines which call for specific fuhnctions

Question 11

what are the functions of neutrophins

Answer 11

retrograde to somata for survival

Question 12

where does neurotrophins as chemoattraction factors take place

Answer 12

peripheral process of sensory neurons in DRG

pseudounipolar neurites

Question 13

what is block apoptosis

Answer 13

neurites die in order sequence d/t not getting neurotrophins

Question 14

what is the importance of chemorepulsion

Answer 14

cytokines avoid abnormal intercations

Question 15

what is self avoidance

Answer 15

intra- neuronal repulsion

same dendrite from same soma

Question 16

what is tiling

Answer 16

inter-neuronal repulsion

different dendrites repulse

Question 17

what is the balance of chemoattraction and chemorepulsion

Answer 17

attraction is the direction of the neurite extension where repulsion is the turning along the extension

Question 18

how does CN II show a balance of chemoattraction and repulsion

Answer 18

temporal retina has chemoattraction towards the same side its on

nasal retina has chemoattraction from cont5ra side and is repulsed from ipsi, thus creating the optic chiasm

Question 18

what gene defines external genitalia

Answer 18

SRY gene on Y chromosome

Question 19

what synthesizes male sexual hormones

Answer 19

cholestrol

Question 20

how does sexual hormones for the male brain develop and affect behavior

Answer 20

2 phases- prenatal and puberty

different LMN neural pools
amgydala for males= voilence d/t fewer astrocytes to insulate and inhibit neurons

Question 21

how does sexual hormones for the female brain develop and affect behavior

Answer 21

1 phase- puberty phase

more astrocytes= less violence

Question 22

what improves the production of dendrites and neurites

Answer 22

sexual hormones

Question 23

t/f

sexual hormones inhibit spinogenesis along dendrites

Answer 23

false, they help the production of spine sprouting

Question 24

where are major synaptic points during development of sexual hormones

Answer 24

dendritic spine

Question 25

where in the brain does oxytocin affect in praire vole

Answer 25

prefrontal cortex caudate/putamen nucleus accumbens

Question 26

where in the brain does oxytocin affect in montane vole

Answer 26

not in

Question 27

where in the brain does ADH affect in praire vole

Answer 27

ventral pallidum

Question 28

where in the brain does ADH affect in montane vole

Answer 28

lateral septal nuclei

Question 29

how does oxytocin and ADH affect behavior in the prairie vole

Answer 29

monogamy meaning that both parents will help

Question 30

how does oxytocin and ADH affect behavior in the montane vole

Answer 30

polygamy meaning only females will raise

Question 31

what is the difference in the female brain vs male brain

Answer 31

female- more developed limbic lobe, olfactry n, SMA meaning more emotional, more internal cues, but difficult spatial orientation male- more developed orbitofrontal, corpus callosum, amygdala

Question 32

how can a more developed corpus callosum in the male brain be bad

Answer 32

if a stroke occurs, slower recovery d/t more damage

Question 33

when synapses start forming in early stages, what is happening

Answer 33

axons extend to target structures due to the amount of neurotrophins mainly to dendrites, axons, cell bodies and target cells

Question 34

how are synapses formed

Answer 34

by complex proteins to form chemical or electrical

Question 35

what happens in late stages of synaptogenesis

Answer 35

synapse pruning if not strengthened

Question 36

what receptors are available during synaptogenesis and pruning in the post synaptic membrane

Answer 36

AMPA and NMDA

Question 37

what is the function of the AMPA receptor in post synaptic membrane

Answer 37

ligand gated ion channel dependent on presynaptic stimuli then will depolarize post synaptic membrane changing NMDA

Question 38

what is the function of the NMDA receptor in post synaptic membrane

Answer 38

Ca2 channel blocked by Mg2

Question 39

what happens when their is above 5 uM of Ca2 in post synaptic membrane

Answer 39

activate kinase transfers more AMPA to post synaptic membrane that strengthens the synapse leading to LTP

Question 40

what happens when their is below 1 uM of Ca2 in post synaptic membrane

Answer 40

activate phosphates leading to endocytosis of AMPA in post synaptic membrane leading to pruning and LTD

Question 41

what are the critical stages of development during pruning of the synapse

Answer 41

birth- guided extension 2- over amount of synapse 6- synapse prune= mature neural connection

Question 42

when does myelination complete

Answer 42

until late 20

Question 43

what is the importance of pruning

Answer 43

helps each neuron send an output conveying different messages done by LTP and LTD LTP- strengthening synapses most used LTD- decrease strength synapse and get rid of synapse not used

Question 44

where are stem cells housed

Answer 44

dentate gyrus of hippocampus and subventricular zone (septal nuclei)

Question 45

how do blast cells migrate

Answer 45

along radial glial process then horizontal transfer

Question 46

what is the function of neuroblasts during neurogenesis

Answer 46

only for granule cells in hippocampus granule and periglomerular cells in olfactory bulb, rostral migration

Question 47

what is the function of glioblast during neurogenesis

Answer 47

mainly oligodendrocytes

Question 48

what is diaschisis

Answer 48

local injury results in both local and distant functional loss ex. MCA stroke affects whole brain, occipital, and L hemineglect

Question 49

what are the 3 types of neuroplasticities

Answer 49

peripheral axon injury- potential full regrowth CNS- activating glia, loss of neurons and function CNS- activating glia, rarely neurogenesis for lost neurons, restore function

Question 50

how does neuroplasticity of CNS regenerate axons

Answer 50

disruption of BBB, recruits glia and last weeks while invading immune cells last months. Both contribute to glial scar formation which can block regeneration of axons

Question 51

what is chromatolysis

Answer 51

death of neurons, no neurotrophins transported back to cell body

Question 52

how does intra-modality reorganization of neuroplasticity work

Answer 52

when the non used part of the brain is used for the same sensory non M1 used for feet now used for hand. more homunculus for hand

Question 53

how does inter-modality reorganization of neuroplasticity work

Answer 53

braille reading for blind patients increases connection to S1 while decreasing connection to dorsal/ventral stream and motor cortex