15 Neural Plasticity

Summary

This lecture delves into neuroplasticity, the brain's remarkable ability to adapt and change throughout life. It highlights key developmental stages like neurogenesis, synaptogenesis, and pruning, which shape neural networks. The importance of myelination for efficient neural communication is underscored, with examples of how it facilitates learning and memory. The discussion also touches on long-term potentiation, enhancing neural connections with use, and the detrimental effects of autoimmune disorders like multiple sclerosis on myelin sheaths, impacting nerve function and information processing.

Takeaways

• 🧠 Neuroplasticity is the brain's ability to change and adapt throughout life, with the most significant changes occurring during early development.
• 🌱 Brain changes are evident as we learn, form new memories, and adapt to new information, demonstrating the brain's adaptability.
• 🤕 After brain injuries, neuroplasticity can lead to the growth of new synapses or the takeover of functions by other parts of the brain, such as the visual cortex activation in Braille readers.
• 🌱 Neurogenesis involves the growth of dendrites and axons, creating a vast number of neurons, especially during early brain development.
• 🔗 Synaptogenesis is the formation of new synapses, which occurs throughout life but is most prominent in early development.
• ✂️ Pruning is the process where the brain eliminates up to 70% of neurons to streamline neural organization and enhance efficiency.
• 🛤️ Myelination is the process of insulating axons with myelin sheaths, which are produced by oligodendrocytes in the central nervous system and Schwann cells in the peripheral nervous system, to speed up electrical signal transmission.
• 🚀 Long-term potentiation is the strengthening of synaptic connections with use, which can lead to more efficient information processing and is likened to the concept of muscle memory.
• 📚 Spreading out study sessions can reinforce neural connections through long-term potentiation, improving recall and demonstrating the value of consistent practice over cramming.
• 🩺 Autoimmune disorders like multiple sclerosis can damage the myelin sheath, leading to nerve dysfunction and impaired communication between neurons, which can manifest in various symptoms affecting daily life.

Q & A

What is neuroplasticity?

Neuroplasticity is the ability of the nervous system to change and adapt in response to information, experiences, and injury. It involves the brain's capacity to reorganize itself by forming new neural connections throughout life.

How does the brain change as we learn?

As we learn, our brain adapts by forming new memories and creating new neural pathways. This process involves the strengthening of synaptic connections, which allows for more efficient information processing.

What happens to the brain following an injury?

Following a brain injury, the brain may exhibit neuroplasticity by forming new synapses or having other parts of the brain take over functions of the injured area. For example, the visual cortex in blind individuals who read Braille can become activated.

What is neurogenesis and how does it relate to neuroplasticity?

Neurogenesis is the growth of neurons, including the development of dendrites and axons. It is a foundational process for neuroplasticity as it provides the structural basis for new neural connections.

Can you explain synaptogenesis and its role in the brain's development?

Synaptogenesis is the formation of new synapses, which are the connections between neurons. This process is crucial for the brain's development as it allows for the creation of new pathways for communication between neurons.

What is pruning in the context of brain development?

Pruning is the process by which the brain selectively eliminates unnecessary neurons and synapses, streamlining neural organization. This helps to optimize the brain's efficiency by removing redundant connections.

How does myelination contribute to the efficiency of neural connections?

Myelination is the process by which a myelin sheath forms around axons, insulating them and speeding up the conduction of electrical impulses. This increases the efficiency of neural communication, similar to how a highway is more efficient than side streets.

What are the differences between oligodendrocytes and Schwann cells in myelination?

Oligodendrocytes are cells in the central nervous system that can myelinate multiple axons simultaneously, while Schwann cells in the peripheral nervous system myelinate only one axon at a time.

What is long-term potentiation and how does it relate to learning and memory?

Long-term potentiation is a process where synaptic connections between neurons become stronger with use, leading to more efficient information processing. It is thought to be a mechanism by which the brain consolidates learning and memory.

How can the lack of myelin affect the nervous system?

The lack of myelin can lead to nerve dysfunction and impaired communication between neurons, as seen in conditions like multiple sclerosis. This can result in various symptoms such as fatigue, vision problems, and difficulty thinking or moving.