Lecture 22 - Developmental & Recovery of Function

Question 1

What is FAS

Answer 1

• Microcephaly
• Tissue loss.
• Cerebral dysgenesis.
• Abnormalities of glial and neuronal migration.
• Holoprosencephaly. (brain can’t develop into two hemispheres properly)

Question 2

neural mass development

Answer 2

• Neonatal brain weighs about 350 grams.
• By adulthood, this weight has increased to around 1200 to 1400 grams.
• By the age of 2 years, brain has reached 75% of its adult weight.

Question 3

why ‘free play’, unstructured is so beneficial

Answer 3

•Because it specifically requires PFC functions like reasoning and imagination.

Question 4

First 1000 days

Answer 4

• Pregnancy àTwo Years old.
• “The brain’s window of opportunity”
• Most critical time for neural development
• Good attachment
• Good toys
• Period of highest brain plasticity
• Considered to be crucial in laying foundations of optimum health, growth, and neurodevelopment across the lifespan.
• Period of highest plasticity.

Question 5

the brain the first 1000 days

Answer 5

• The human brain at 5 months post-conception is a smooth, bi-lobed structure.
• By 9 months, i.e. term birth, it has gyri and sulci indicative of significant complexity, looking far more like the walnut-like adult brain.
• At birth, rapidly developing brain areas include the hippocampus and the visual and auditory cortices.
• Characterized by rapid rates of neuronal proliferation, growth and differentiation, myelination, and synaptogenesis.
• Different regions and processes of the brain exhibit growth trajectories that span and peak at different times during these 1000 days.

First postnatal year:

•Rapid growth of the language processing areas as well as early development of the PFC that will control “higher processing” such as attention, inhibition, and flexibility.

Question 6

Baby/Toddler brain devel

Answer 6

• Prenatal – All five senses begin to function before birth.
• 2-6 months– Significant ‘wiring’ of the brain occurs in the first months of a child’s life.
• 6-9 months – By nine months brain has already undergone a rapid growth spurt that helps form connections between what they see, hear, feel and taste.
• 3 years –By three years of age, a child’s brain has around 1000 trillion synapses.

Question 7

brain dev 3-5 years/adolescence

Answer 7

• 3-5years – Child’s brain development is built upon the now solid foundation created in the first five years.
• Adolescence – When adolescence is reached, synapses will number around 500 trillion(half), a figure that remains relatively steady into adulthood.

Question 8

Neuronal Migration

Answer 8

• Method by which neurons travel from their origin or birthplace to their final position in the brain.
• Migration during development brings different classes of neurons together so that they can interact appropriately.
• Involves three distinct phases: extension of the leading process, movement of the cell body, and retraction of the trailing process.

they move like a caterpillar

Question 9

Exuberant synaptogenesis:

Answer 9

•Explosion of synapse formation during early brain development.

Question 10

Synaptic Pruning

Answer 10

• Up to two years: a steady increase in the synapses in the brain.
• After this period of rapid proliferation, connections are reduced through a process called pruning, so that brain circuits become more efficient.
• Connections proliferate and prune in a prescribed order, with later, more complex brain circuits built upon earlier, simpler circuits.
• By adulthood, 50% of these synapses have been shed (or “shit” in New Zealand)

Question 11

Kennard Principle:

Answer 11

• The earlier in life a brain lesion occurs, the more likely it is for some compensation mechanism to reverse at least some of the lesion’s negative effects.
• “the younger the kid, the better the recovery”

Question 12

Theories of Recovery of Function

• Artifact Theory
• Anatomical Reorganization Theory
• Functional Adaptation Theory

Question 13

Artifact Theory

Answer 13

•Claims that function is not really lost, just temporarily suppressed or impaired.

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• Consider a person with a TBI as just being “suppressed” in being able to perform a particular behavior.
• Hopeful, but not overly realistic. Ex, HM will never get some function back

Question 14

Anatomical Reorganization Theory

Answer 14

• Claims that after brain injury, other areas of the brain take over the functions of the areas that have been damaged.
• More in line with the research
• We see this in movement (phantom limb), language, girl with half a brain

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Question 15

Functional Adaptation

Answer 15

•Refers to the ability of the person to relearn, through other means that those originally employed, behaviors that were lost in the damage.

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• This relearning is then capable of enhancing the reorganization of the nervous system.
• Behaviour and practice can reactivate/activate brain areas/restructure

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Question 16

Boosting Neuroprotection

Answer 16

• Intermittent fasting: increases synaptic adaptation, promotes neuron growth, improve overall cognitive function, and decreases the risk of neurodegenerative disease.
• Traveling: exposes your brain to novel stimuli and new environments, opening up new pathways and activity in the brain.
• Using mnemonic devices: memory training can enhance connectivity in the prefrontal parietal network and prevent some age-related memory loss.
• Learning a musical instrument: may increase connectivity between brain regions and help form new neural networks.
• Non-dominant hand exercises: can form new neural pathways and strengthen the connectivity between neurons.
• Reading fiction: increases and enhances connectivity in the brain.
• Expanding your vocabulary: activates the visual and auditory processes as well as memory processing.
• Creating artwork: enhances the connectivity of the brain at rest (the “default mode network” or DMN), which can boost introspection, memory, empathy, attention, and focus.
• Dancing: reduces the risk of Alzheimer’s and increases neural connectivity.
• Sleeping: encourages learning retention through the growth of the dendritic spines that act as connections between neurons and help transfer information across cells (Nguyen, 2016).