Refinement of Synapses and Plasticity Over the Lifespan Flashcards Preview

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Flashcards in Refinement of Synapses and Plasticity Over the Lifespan Deck (55)
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1
Q

True or False:

The synaptic connections are essential for brain function

A

True

2
Q

Does plasticity occur throughout the lifespan

A

Yes, it weakens as we age

3
Q

What happens once an axon tip reaches its destination

A

Rudimentary synapses start to form

4
Q

Does migration lead to wiring that is perfect

A

No it is only approximate

5
Q

How is detailed tuning of neural connections occur (2)

A
  1. Eliminating the extra links

2. Strengthening functional synapses based on neural activity

6
Q

True or False:

During development there is constant rearrangement of synaptic connections

A

True

7
Q

What is the purpose of refining/pruning our synaptic connections

A

It gives us specificity

8
Q

What is the somatotopy of our brain due to (hamonculus)

A

Refinement of synapses due to relative sensory and motor experiences

9
Q

True or False:

Any loss of motor or sensory input will result in changes to the somatotopy over time

A

True

10
Q

What are the 2 important steps of brain wiring

A
  1. Establishing correct pathways and targets

2. Fine tuning based on experience

11
Q

What is synaptic plasticity

A

The variability in strength of a signal transmitted through a synapse

12
Q

True or False:

Once a neuron is placed is overproduces synapses in an orderly manner

A

False

13
Q

When does the majority of the cortex develop

A

The first 2 years of life

14
Q

What is older the brainstem or cortex

A

Brainstem

15
Q

Where are neurons initially produced

A

Along the central canal in the neural tube

16
Q

After the neurons are produced around the central canal where do they migrate to

A

Their final destination in the brain

17
Q

Once the neurons reach their destination in the brain what do they do

A

Collect together to form each of the various brain structures

18
Q

How many synapses are there per cortical neuron

A

15000

19
Q

How many synapses are formed per second in the first 2 years

A

1.8 million per second

20
Q

How much does the cerebral cortex thicken in the first year

A

It triples

21
Q

True or False:

The quantity of information cannot be genetically micromanaged by chemical environments alone

A

True, experience plays a huge role

22
Q

What is experience expectant

A

Common early experiences that provide essential catalysts for normal brain development

23
Q

What is an example of experience expectant

A

Early visual stimulation, hearing, language, and coordinating vision and movement

24
Q

True or False:
The developing brain does not require these typical experiences, that are unique to each species, and relies on them as a component of its growth

A

False, It is required

25
Q

What is experience dependent

A

Idiosyncratic/individual experience that fosters new brain growth and refines existing brain structuress

26
Q

What is an example of experience dependent

A

Reading, golf, singing, music, vocab

27
Q

Who determined how plasticity occurred

A

Hebb

28
Q

What did Hebb say about plasticity

A

Neurons that fire together wire together, but neurons that fire out of sync lose their link

29
Q

Example of Hebb’s plasticity

A

If you show a kid a ball and say the word ball both synapses will be strengthened eventually leading to increased strength of synapse that allows us to make a mental image of the ball. After awhile you can say ball and the kid will get a mental image of a ball

30
Q

True or False:

Synapses are vacated when they are not strengthened

A

True

31
Q

What is a sensitive period

A

Anatomy and physiology are especially sensitive to modulation of the experience

32
Q

Does a sensitive period occur rapidly of gradually

A

Gradually

33
Q

What is a critical period

A

Period of maximal sensitivity in which appropriate stimulation is essential for the normal development of a pathway or set of connections

34
Q

Does a critical period occur rapidly or gradually

A

Rapidly

35
Q

Can development beyond the critical period happen

A

Nope

36
Q

What is a critical period associated with

A

A lot of synapse formation or proliferation of cells

37
Q

Where is the right visual field represented on in the retina

A

The left hemiretina

38
Q

Where do the two primary visual cortices share information with each other

A

The splenium of the posterior corpus callosum

39
Q

True or False:

Ocular dominance is time dependent

A

True

40
Q

What are ocular dominance columns

A

Stripes of neurons in the primary visual cortex of some mammals

41
Q

Do the ocular dominance columns respond to both eyes or only one eye

A

One eye only

42
Q

True or False:

The ocular dominance columns span multiple cortical layers

A

True

43
Q

What is monocular deprivation

A

Depriving one eye from recieveing sensory input

44
Q

What does monocular deprivation causes (2)

A
  1. Columns to degrade
  2. Non-deprived eye forms synapses with the cortical cells that would have been occupied by those representing input from the deficient eye
45
Q

Prenatally what provides the feedback to establish which neural circuits are the right ones to strengthen

A

Spontaneous activity and input

46
Q

Prenatally what controls the motor control of the fetus

A

The midbrain

47
Q

Why is the midbrain in charge of motor control of the fetus

A

The cortex is not developed

48
Q

How are the motor neural circuits strengthened prenatally

A

The fetus moves their limbs

49
Q

True or False:

Research indicates that newborns preferentially recognize the sounds of their native language over others

A

True

50
Q

How are the auditory neural circuits strengthened

A

Speech signals reaching the womb

51
Q

How are visual neural circuits strengthened

A

Systematic moving patterns of activity of neighboring retinal ganglion cells are spontaneously generated

52
Q

What do the retinal ganglion cells firing do

A

Tells the thalamus to send input to the visual cortex producing bursts of color

53
Q

What are some circumstances that may alter the normal somatotopy (4)

A

Stroke, hypoxia, toxins, loss of limb

54
Q

True or False:

Any loss of input or output can affect the plasticity of synapses and representation of the affected area in the brain

A

True

55
Q

What are 4 principles that can effect plasticity

A
  1. Intensive motor skills repetition
  2. Enriched physical and social environments
  3. Aerobic exercise
  4. Constraint induced movement therapy