# Neuroplasticity

By [Bhau](https://paragraph.com/@bhau) · 2022-02-03

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![](https://storage.googleapis.com/papyrus_images/a04539557538fda8ee7453ab73bedfbf734d545452910d23573598298e21aae5.png)

### THE ORGANIZATION OF BEHAVIOR

…is summarized by the phrase above. Also known as the [Cell Assembly theory](https://en.wikipedia.org/wiki/Hebbian_theory#:~:text=Hebbian%20theory%20is%20a%20neuroscientific,neurons%20during%20the%20learning%20process.), this model was introduced by Donald Hebb in the book titled _The Organization of Behavior_. This fundamental principle,

“Neurons that fire together, wire together; and neurons out of sync, fail to link,”
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is a simple and elegant framework to contextualize [Associative Learning](https://en.wikipedia.org/wiki/Learning#Associative_learning) and understand **Neuroplasticity** - the brain’s **_capacity for Re-Organization_**.

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Zooming in to the brain…
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![](https://storage.googleapis.com/papyrus_images/e8fcdec01c3f4a2c6c1d596beff00fa5ef5e2d5f1e3e01860cac87a2bb2bd498.gif)

…we can find the basic unit of our nervous system - the **Neuron**.

When neurons “fire,” they communicate with other connected neurons:

![](https://storage.googleapis.com/papyrus_images/e73724e47dabe548da559591a7139aa2e745caa8e8937ee64eff30fa2d865433.gif)

Information, in the form of electricity, is transmitted downstream along connected neurons. The scientific term for this kind of “firing electricity” is known as an [Action Potential](https://en.wikipedia.org/wiki/Action_potential).

The place where a neuron connects with another neuron is called a **Synapse**:

![](https://storage.googleapis.com/papyrus_images/6bae5cd80aa4bb6e506c7a0235178fef52a254dbab67b91bc0525689b6cc28f1.gif)

At the Synapse, this **_electricity is converted into chemical energy_**, and information is passed along through molecules known as **_Neurotransmitters_** (_triangles above_).

When Neurotransmitters traverse the Synapse across the synaptic cleft, they bind to the **_Post_\-Synaptic** Neuron:

![](https://storage.googleapis.com/papyrus_images/55731254f397ff83ea7a01c54519ac50ab26da421461f723d93e9fc13de1c0bd.gif)

Here, the chemical energy is **_converted back into electricity_**, causing the Post-Synaptic Neuron to fire.

And because each neuron branches off to connect with **numerous** other neurons…

![Dendrites (left) receive signals, and Axons (right) transmit them to other neurons at the Synapse. ](https://storage.googleapis.com/papyrus_images/89dff76a6a4f6c74c3d23cc9cff9e79d4945bb56e256fc1c8be1b1b8e747bd27.gif)

Dendrites (left) receive signals, and Axons (right) transmit them to other neurons at the Synapse.

![Dendrites (top) receive signals, and Axons (bottom) transmit them to other neurons at the Synapse.](https://storage.googleapis.com/papyrus_images/239f29bd79640490cf4ea514cd72e75cdeb05292fb32e5b16314172bef100890.gif)

Dendrites (top) receive signals, and Axons (bottom) transmit them to other neurons at the Synapse.

…information is distributed throughout the brain in this manner…

![](https://storage.googleapis.com/papyrus_images/507f9247fc237a1c4159897402042e71e1d4b25a6e6d34037cbb8a1e00c83e1c.gif)

…on the order of milliseconds.

Continuously.

Neuroplasticity in Motion:
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![](https://storage.googleapis.com/papyrus_images/2d2de38cdc74adee1252012b4146595b79a1e4759f24a8ed3047d9c3a6b539dc.gif)

Left: As the neurons fire, they wire together to strengthen the Synapse.

Right: As the neurons fall out of sync, the Synapse weakens and un-links.

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Learning and Memory
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As information is distributed along neurons connected within **_Neural Networks_**, it is stored in the form of [Engrams](https://en.wikipedia.org/wiki/Engram_\(neuropsychology\)).

The **more the neurons fire, the more potently they wire** to integrate the data being processed.

![](https://storage.googleapis.com/papyrus_images/6f5fa17d45030f62ca8c599b7d938890f87ef04f390d0f3e276ddb9295ce61bd.jpg)

**Synaptic strength** of the Post-synaptic neuron (green) is much greater after **_Repeated Stimulation_** for 1 week. This is measured not only through the synaptic receptor density of the neuron, but also through recordings of a stronger neuronal impulse.

**_Repeated Stimulation_** mentioned above includes the kind of stimulation conducted through **TMS**:

### Electrical stimulation vis-à-vis Magnetic stimulation.

How does this increase the synaptic strength?
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The answer is **Long Term Potentiation**:

![](https://storage.googleapis.com/papyrus_images/852e70619b95ce39f6b2889f6782a82bda597f5b214884b04163648d2df6ee22.gif)

**Long-Term Potentiaion** ([**LTP**](https://en.wikipedia.org/wiki/Long-term_potentiation)) describes the **_long-lasting_** persistent strengthening of synapses brought about by **_repeated stimulation._**

For reference, **Long-Term Depression** ([**LTD**](https://en.wikipedia.org/wiki/Long-term_depression)) is the opposite of this process. It entails the un-linking of neurons after falling out of sync.

Key Takeaways:
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### REPEATED NEURONAL STIMULATION (TMS)

### ↓

### GREATER SYNAPTIC STRENGTH

### ↓

### ROBUST LEARNING

### ↓

### DEEPER CONSOLIDATION OF BEHAVIOR INTO MEMORY

Zooming out…
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![](https://storage.googleapis.com/papyrus_images/fdf79a3385cee0c7c856cbfdbb63216c37a9604ebfd9945a043a229ec2e13e7a.gif)

…we can see how changes at the **_Micro_** level (**Neurons**) would influence pathways and connections at the **_Macro_** level ([**Connectome**](https://en.wikipedia.org/wiki/Connectome)).

The **Connectome** - the neural connections in our brains - was mapped by the **Human Connectome Project** (_similar to the mapping of our genes in the Human Genome Project_):

![](https://storage.googleapis.com/papyrus_images/fe7ef91386f07aaff464d479a2f967220751e64cfe2f63727c457e3e9b35178b.jpg)

These neural connections give rise to what are known as **Structural and Functional Brain Networks**. And as we’ve explored here, these networks can be reconfigured by leveraging Neuroplasticity.

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*Originally published on [Bhau](https://paragraph.com/@bhau/neuroplasticity)*