2. Neurodevelopment & Neuronal Plasticity Flashcards
Initially the neural tube is o____-c____ thick, t____ on both e____
As the neural tube widens, the extensions of the cells e____ still holding on to the o____ wall
one-cell, touching, ends
elongates, outer
Neurogenesis does not take place with neuronal division… neurons do not d____. Immature cells called s____ cells divide to form p____ cells. Each p____ cell can be a n____ or a g____.
divide
stem
progenitor (precursor)
progenitor
neuroblast, glioblast
It was noticed in early observations that the cells undergoing m____ were always c____ to the inner surface of the neural tube, known as the v____ z____ (brain’s nursery)
mitosis, closer, ventricular zone
The neural tube gives rise to the v____ s____ in a mature brain
ventricular system
Cell migration refers to the m____ of the newly formed cells towards the o____ layers
movement, outer
The cortex develops in an i____-o____ manner, and this is seen across s____
inside-out, species
A p____ m____ predisposes cells born in a certain region to migrate to a certain location of the c____
primitive map, cortex
Cell migration occurs with the help of:
1. C____ s____
2. P____ s____ provided by r____ glia
- Chemical signals
- Physical support, radial
A large wave of neurons are still m____ in the f____ c____ after b____. Most of these will become i____ G____ i____
migrating, frontal cortex, birth
inhibitory GABAergic interneurons
Once they arrive at their destination, i____ neurons begin to express g____ that will allow them to become a particular type of cell. They start to form an a____ and d____ that will give them their distinct shape.
immature, genes
axon, dendrites
Dendritic development involves d____ a____ and growth of d____ s____
dendritic arborisation (branching), dendritic spines
Induction is the ongoing c____-c____ interactions via the s____ of c____ where cells influence the fate of their neighbouring cells
cell-cell, secretion, chemicals
In cell Differentiation and Maturation, if immature cells are r____ from a given region, they will be replaced by s____ neurons that will arrive in this area and acquire the same c____
removed, subsequent, characteristics
Because of the ability of immature cells to differentiate into any type of cell based on the a____ c____ (p____), they can be used t____ to help tackle diseases such as P____ disease
area characteristics, pluripotency, therapeutically, Parkinson’s
Synaptogenesis is guided by a variety of c____ and s____
cues and signals
The growing end of the axon is called a g____ c____. The axons extend by adding m____ to the t____ of the axon
growth cone, microtubules, tip
Growth cones are attracted to c____ released from t____ s____. These chemicals are c____ a____ molecules and t____ molecules.
chemicals, target sites, cell adhesion, tropic
In synpatogenesis, once a successful c____ has been made, a____ and t____ induce each other to construct m____ to help them a____ to one another and to form a s____
contact, axon, target, machinery, attach, synapse
The majority of our synapses take place a____ b____ and continue to r____ themselves throughout l____
after birth, rearrange, life
Filopodia can make p____ C____ WITH OTHER CELLS (C____ G____) OR THEY CAN BE C____ G____ (C____)
physical contact
contact guidence
chemically guided
chemotropism
Filopodia have p____ on their m____ which serve as r____ that ‘r____’ various molecules to which they will a____ to or not
proteins, membrane, receptors, recognise, adhere
Growth cones d____ and s____ among a wide range of guidance cues
detect, select
Both contact guidance and chemotropism can be either a____ or r____ to the growth cone
attractive, repulsive
The same cue may be attractive to one cone and repulsive to another or the nature of the relationship may change with time
Successful synapses are those which are a____ and thus are m____ and s____
active, maintained, strengthened
Synpases that are not successful are e____. This is called s____ p____
eliminated. Synaptic pruning
The determining factor is successful synapses is e____. This is the “u____ i____ o____ l____ i____” principle
experience
use it or lose it
Due to the ability of the brain to c____ form new synapses and e____ others, there is p____
constantly, eliminate, plasticity
Synaptic rearrangement occurs throughout l____ and is related to learning or e____
life, experience
Adolescence is a period of increased s____ p____. The p____ c____ is still immature while other areas are better developed such as the l____ s____.
synaptic pruning
prefrontal cortex
limbic system
Gogtay et al 2004 (NIMH) did brain scans of 4-25y olds every 2 years and found that…
1. G____ m____ thickens in childhood but then it begins to thin out g____
2. S____ p____ starting from the b____ to the f____ by early adulthood
3. Increase in w____ m____ which peaks in adulthood
4. Perhaps a second phase of “u____ i____ o____ l____ i____”
5. The process is completed earlier in g____ than in b____
grey matter thickens in childhood but then it begins to thin out gradually
Synaptic pruning starting from the back to the front by early adulthood
Increase in white matter (myelination) which peaks in adulthood
Perhaps a second phase of “use it or lose it”
The process is completed earlier in girls than in boys
The official word for Programmed Cell Death is a____
Apoptosis
When axons initially reach their targets, they form synapses with several cells, there is overabundance. In fact, there are more neurons and more connections than we will eventually need, so some will have to go.Many will not form active synapses and will be eliminated. This is called n____ d____.
Neural Darwinism
Apoptosis is an a____ process. Cells that undergo apoptosis are e____ g____ that enable them to d____ (d____ g____ called c____)
active
expressing genes
die]death genes called caspases
Proteins s____ by t___- cells called s____ s____ promote the survival and growth of neurons. It was discovered that there are several such proteins, a family of these factors named n____ f____
secreted, target, survival signals.
neurotrophic factors
In order to avoid apoptosis and survive, a neuron will need:
1. N____ (growth factors) from its t____ cells
2. A____ c____ with other neurons which leads to the s____ of the s____
- Neurotrophins, target
- Active communication, strengthening, synapses
Myelination refers to the process by which g____ form a f____ s____ that covers the a____ of the neurons
glia, fatty sheath, axons
Myelin speeds up the t____ of neural i____ and allows for its ‘s____ c____’
transmission, impulses, ‘saltatory conduction’
There is a correlation between myelination and the ability to g____
grasp
There are a few “n____” regions in the adult human brain. O____ e____ contains cells that c____ d____ to provide new o____ s____ neurons and replace d____ ones. Also, cells produced in the s____ z____ (SVZ) of the lateral ventricles migrate to replace i____ in the adult o____ b____. This long path of migration towards the o____ b____ is called the R____ M____ S____ (RMS).
neurogenic
Olfactory epithelium
continuously divide
olfactory sensory
damaged
sub ventricular zone
interneurons
olfactory bulb
olfactory bulb
Rostral Migratory Stream
Newborn cells from the s____ z____ (SVZ) migrate to the o____ b____ and become i____. A____ wrap around the migrating neurons to create a ‘p____’ that keeps them on the right path. This occurs t____ l____.
subzentricular zone
olfactory bulb
interneurons
Astrocytes
pipeline
throughout life
The g____ l____ of the d____ g____ of the hippocampus was the first neurogenic area to be d____. New neurons are c____ and a____ to the d____ g____ throughout life.
granular layer
dentate gyrus
discovered
created and added
dentate gyrus
Recovery is better in y____ brains than in o____ brains and it is better in the p____ than it is in the b____
younger, older
periphery, brain
The mechanisms of recovery in the brain mainly involve new branching of a____ and d____, a process known as c____ s____. New branches formed by non-damaged axons a____ to v____ spots of dendrites and cell bodies. The cells s____ n____ that allow c____ s____ to occur.
axons and dendrites
collateral sprouting
attach
vacant
secrete neurotrophins
collateral sprouting
The brain adapts according to e____ stimuli, known as n____
environmental
neuroplasticity (synaptic plasticity)
Researchers asked sighted and blind people to feel Braille letters or other items and say whether they were the same or different. PET scans indicated substantial activity in the o____ c____ of blind people whilst they performed these tasks.
occipital cortex
fMRI study with blind participants showed robust activity in the v____ c____ while reading B____, despite complete a____ of vision.
visual cortex
Braille
absence
Blind people recruit brain areas usually used for vision to perform a____ l____ tasks
auditory localisation tasks
Rats raised in an enriched environment develop a t____ c____ and have increased d____ b____. Much of the enhancement was due to p____ a____. Increased d____ b____ was correlated with i____ a____ to l____.
thicker cortex
increased dendritic branching
physical activity
dendritic branching
improved ability to learn
A critical period is a period during which the brain is most s____ to a s____ e____.
sensitiver
specific experience
Sensitive periods, accordion got Bateson (1979) could be conceived of as a b____ o____ of a window of v____, of n____ and also of o____.
brief opening
vulnerability, need, opportunity
E____ studies show evidence for e____ factors that lead to p____ later in life
Epidemiological, environmental, pathology
