Title: Psychology / Biopsychology / 05_DevelopmentAndPlasticity
Tags: Biopsychology::05_DevelopmentAndPlasticity Biopsychology::Semester_1

Q: What will the neural tube and neural crest develop into later on?
A: neural tube: central nervous system
neural crest: peripheral nervous system

Q: What is special about stem cells?
A: They are omnipotent, meaning they can develop into any cell in the body. They can also replicate by dividing.

Q: What are neuroblasts?
A: Precursor to cells of the nervous system, they can either become a neuron or a glia cell.

Q: What property of stem cells do neuroblasts retain?
A: The ability to replicate by dividing → this results in potential exponential growth.

Q: How is it defined what kind of cell the neuroblasts develop into?
A: By the surrounding chemical signals (by this logic, location has a great effect)

Q: What is the process of cells traveling inside the brain called?
A: Cell migration

Q: What do radial glia cells do?
A: They provide scaffolding for the migrating neurons to move across.
(When the brain is no longer developing, these glia cells get heavily reduced)

Q: Where do radial glia cells originate?
A: In the ventricular zone.

Q: How many layers does the human neo-cortex have?
A: 6 layers, each with slightly different cells.

Q: What is the purpose of subplates during the development of the neo-cortex?
A: They are large neurons that build a stabilizing basis, they are removed/reduced once the development finishes.

Q: What makes the Layer I of the neo-cortex special?
A: It contains no nerve bodies, only neurites.

Q: How do the layers of the neo-cortex differ?
A: The contained neurons differ in shape, size and function.

Q: How is the neo-cortex of dyslexic people malorganised?
A: Bodies from layer 2 can be found in layer 1 (normally, there should be no bodies in layer 1)

Q: What is it called when neuronblasts develop the dendrites and axon?
A: Differentiation

Q: Do new neurons develop in adults?
A: Yes, however, at a much slower rate

Q: What is the growth cone?
A: A structure at the end of an axon that guides the branching of the axon (basically pulling the axon out of the cell body).

Q: What are filopodia?
A: Finger/Spike like structures coming out of growth cones.

Q: How do neurites find their way towards making correct connections when developing?
A: They are chemically attracted.

Q: Synapses between axons and dendrites are formed in 3 steps. What are those?
A: 1. A filipodium of the dendrite connects to the axon.
2. The axon develops a presynaptic active zone (including vesicles)
3. The axon releases some neurotransmitters so that the postsynaptic receptor cluster can be built using the correct receptors.

Q: What is the purpose of the Nerve Growth Factor?
A: Neurons take it up when releasing neurotransmitters.
If a neuron is inactive and does not receive NGF, it is programmed to suicide.

Q: How does the synaptic density in the frontal cortex change between the ages 1 and 20?
A: The density decreases.

Q: What is neural pruning?
A: Neurons that do not make efficient contact with other cells will die. This results in massive nerve cell loss in the brain shortly before and after birth.

Q: What is the connection between neural pruning and autism?
A: People with autism show a very high brain volume along with a disorganized structure → the pruning was either ineffective or delayed.

Q: What use does synaptic elimination have at neuromuscular junctions?
A: Synaptic elimination enables finer motor skills by reducing the connections so that only the most important connections stay.

Q: What is meant by "neurons that fire together, wire together"?
A: Neurons that fire at the same time process similar information, thus their connection is strengthened, while neurons that fire out of sync lose their link.

Q: What is a Hebbian modification?
A: A form of synaptic rearrangement where neurons that fire synchronously strengthen their synapses, ultimately building their own little circuits (out-of-sync ones weaken theirs).

Q: What is Neurogenesis?
A: The process of neuroblasts creating new nervous system cells by dividing and differentiating.

Q: What was the takeaway of the ferret study of Sur and colleagues?
A: During a sensitive period, the input into the brain parts determines their function.

Q: What stimulates neurogenesis in adult brains?
A: A social and/or enriched environment.

Q: How can stem cells be used to help (animal) stroke patients?
A: Stem cells cause neurons to regrow, leading to a faster recovery of motor function.

Q: Why are stem cells usually not used in humans to restore brain cells?
A: They are hard to control, so uncontrolled growth and tumor building are likely (using already differentiated neurons has a lower risk and has been shown to be effective in mice)

Q: What is the basic idea behind learning-dependant plasticity?
A: Learning new skills changes the structure of the brain in related regions.

Q: What is the concept of cross-modal plasticity?
A: When certain parts of the brain go unused (e.g. blind people), these areas adapt to help out in other functions (e.g. hearing)

Q: Why are blind people better at hearing?
A: Part of their (normally unused) visual cortex now helps out with the processing of auditory information.

Q: On a neuron level, how can certain brain areas take on the jobs of others?
A: The brain develops neurons that respond to multiple signals (e.g. auditory and visual) and thereby connect the two systems.

Q: What happens to the regions of the brain that correspond to certain limbs after amputation?
A: Not a lot. They get modified a bit, but the representation remains in the brain.

Q: What brain activity causes phantom pain?
A: The brain underwent a maladaptive structural change that causes an unwanted coactivation of the areas representing the amputated body part when unrelated actions are being performed.