L16 - Neurodevelopment Flashcards
What are the main phases of prenatal development?
Zygote (fertilised egg)
Embryo (week 8 till birth)
Fetus (remaining prenatal development)
What is the aim of neurodevelopment?
To form a functional nervous system through precise cellular processes
E.g., cell migration, differentiation and synaptogenesis
What happens during fertilisation?
Sperm enters the egg forming a zygote with 46 chromosomes that rapidly divides and develops
What are the 3 cell layers formed after one week of development?
Ectoderm (develops in nervous system)
Mesoderm
Endoderm
what is the neural tube?
A structure formed by the ectoderm that eventually becomes the brain and spinal cord
What are the 6 stages of nervous system development?
Neurogenesis
Cell migration
Differentiation
Synaptogenesis
Neuronal cell death
Synapse rearrangement
What is neurogenesis?
The mitotic division of non-neuronal cells to produce neurons
What’s cell migration?
They guide neurons to their final destinations by acting as scaffolding.
What’s differentiation?
The process where cells acquire their specific functions and structures as neurons.
What’s synaptogenesis?
Formation of synaptic connections through the growth of axons and dendrites
What’s neuronal cell death?
A natural process where excess neurons die to refine neural circuits.
What’s synapse rearrangement?
The process where some synapses are strengthened while others are eliminated to optimise neural connections.
What role do radial glial cells play in cell migration?
They guide neurons to their final destinations by acting as scaffolding
How does neuronal connections from circuits?
Repeated use strengthens connections, while unused connections are pruned.
What’s synaptic pruning?
The elimination of unused synaptic connections to enhance efficiency
What role do early experiences play in brain architecture?
They shape neural circuits by reinforcing frequently used pathways
What’s myelination?
The process where glial cells wrap axons in myelin, speeding up signal transmission
When is myelination most active?
During the first few years of life, continuing into adulthood
How does myelination affect cognitive development?
It correlated with improves processing speed and the maturation of complex brain functions
What is a common pathology of myelin?
Multiple sclerosis, where the immune system attacks the myelin sheath
How does the infant brain differ from the adult brain?
The infant brain has fewer established connections and is less myelinated, making it more plastic but less efficient
Why os the infant brain more plastic than the adult brain?
It’s rapidly forming and recognising connections in response to environmental stimuli
How are cognitive, social and emotional development interconnected?
They rely on shared neural circuits that form critical developmental periods
What is the importance of early neural circuits?
Simple circuits provide the foundation for more complex abilities like memory, language, and motor skills.
What is the role of genes in neurodevelopment?
Genes provide the blueprint, but environmental experiences act as the “software” driving development.
Why is early intervention critical in neurodevelopmental disorders?
Early experiences have long-lasting effects on brain architecture, making timely interventions crucial.
