The NEURON is a single brain cell. We have billions! Neuronal communication between two brain cells (neurons) are fundamental to all we think and do. It has a unique structure because of this communication function. I will describe with words the parts of the neuron and then give you some Youtube sources to follow up with illustrations.

QUESTION

NEURON AND NEURONAL COMMUNICATION

The NEURON is a single brain cell. We have billions! Neuronal communication between two brain cells (neurons) are fundamental to all we think and do. It has a unique structure because of this communication function. I will describe with words the parts of the neuron and then give you some Youtube sources to follow up with illustrations.

The body of the neuron contains the dna of the cell. It is encircled by these branch-like parts called DENDRITES (the Greek word for trees) that reach out into space around the cell. At the tip of the dendrite, is the RECEPTOR. That is the part that receives the message from the previous cell. Receptors are very particular about what they receive. Both message and receptor must have the same form for the message to go through. This is because we are bombarded and inundated with so much information and sensations that the brain has multiple ways to filter out what is unnecessary to be able to focus on what we want. The necessary match between message and receptor is one of those filters that reduces the noise coming at you. Think of Cinderella and her shoe—it only fit her foot. Think of OJ and his glove—“if it doesn’t fit, you must acquit” claimed his lawyer. If the match is made the message is received by the receptor, enters the dendrite, travels through the CELL BODY and then meets its next challenge to get through. Here is where it meets the AXON HILLOCK. This is a sort of “jury” that judges whether the message should get through by using two criteria: the message must be repeated enough times, OR it must be strong enough to convince the axon hillock that it is worthy. Think about the role of repetition in learning. That is how you learn! If you want to learn a language or play a musical instrument, what do you do? Practice! That repetition convinces your axon hillock that the message is important and you learn what you have practiced. Or, if a message comes that is particularly strong (think of a stressful or traumatic memory), it will get through. As the child grows, parts of the brain are MYELINATED (MYELIN), a fatty substance that coats the axon to speed the message along. Only the parts of the brain that are myelinated will function well. That is why teenagers make such poor decision because the judgment part of their brains is not fully myelinated yet.

Now, the message shoots down the AXON without interruption—that is, unless you happen to have the autoimmune disease called MS or Multiple Sclerosis. This disease attacks the myelin of the brain and spinal column that coats the axon as an enemy rather than a part of oneself. When these immune cells eat through the myelin, the neuronal messages cannot proceed and functioning of that part of the body either slows or stops. Without MS disrupting the flow, the neuronal message speeds down the axon to the end that is named the AXON TERMINAL. That is where magic happens! All this time the neuronal message has been electrical and now it has to travel across a chemical environment to reach the next cell. In the axon terminal, the electrical message changes into a chemical message in these balloon-like structures called VESICLES. Those vesicles release the chemical message, called NEUROTRANSMITTER, into the space between the cells to reach the next cell where the process repeats again.

That space between the cells, called SYNAPSE, is all-important especially in manipulating the actions of the cells through medication and drugs. The neurotransmitters can do many things in that space. Let’s use antidepressants as an example. If you are depressed, it is because your brain doesn’t have enough of the neurotransmitter called SEROTONIN that produces the feeling of calm and happiness. When one cell tries to send it to the next, the recycling system of the brain washes it away before the next cell can get enough to make you happy and you become depressed. Your psychiatrist writes you a prescription of a type of drug called SSRI (selective serotonin reuptake inhibitor) that will keep the serotonin longer in the synapse so the next cell can receive the message of your happy mood. Pills and ingested substances can create SIDE EFFECTS because they are delivered through your blood stream and so go throughout your body, not just to the intended target.

I would like you to see visuals and discussions of this essay by taking advantage of the Khan Academy lessons on YouTube. Please type in Khan Academy and the following presentations:

Anatomy of Neuron

Neuronal synapses

Psychoactive drugs

Substance Use Disorder

Now I’m sure that you are wondering what your quiz on this material will be, yes? I would like you to make a drawing of all the parts and terms of the neuron (12 total) that I explained above. Label each part and place it accurately on the drawing. See the illustrations in your text, online, and on YouTube.

ANSWER

Exploring Neurons and Neuronal Communication: Structure, Function, and Significance

The neuron is a fundamental building block of the brain, responsible for neuronal communication. Billions of neurons work together to enable our thoughts and actions. To understand the structure and function of a neuron, let’s explore its various components.

The neuron’s body contains the DNA of the cell and is encircled by dendrites, which resemble branches of a tree. Dendrites reach out into the surrounding space, and at their tips, they have receptors. Receptors are highly specific and must match the form of the incoming message for communication to occur (Stangor, 2014). This matching mechanism serves as a filter, reducing the overwhelming amount of information and sensations bombarding our brains. Just like Cinderella’s shoe or OJ’s glove, if the match is made, the message is received by the receptor, travels through the dendrite, and reaches the cell body.

Within the cell body, the message encounters the axon hillock. The axon hillock acts as a “jury,” assessing whether the message should proceed based on two criteria: repetition or strength. Repetition plays a crucial role in learning, as it convinces the axon hillock that the message is important and facilitates the learning process. Alternatively, if a message is particularly strong or emotionally charged, it can overcome the axon hillock’s judgment. As a child grows, certain parts of the brain undergo myelination, a process in which a fatty substance called myelin coats the axon, increasing the speed of message transmission. Only myelinated brain regions function efficiently, which partially explains why teenagers may make impulsive decisions due to incomplete myelination in the judgment areas of their brains.

Assuming there are no interruptions, the message swiftly travels down the axon, reaching the axon terminal. At this point, the electrical message undergoes a transformation into a chemical message within balloon-like structures called vesicles (Lazzara, 2020). These vesicles release neurotransmitters, the chemical messengers, into the synapse, which is the space between two neurons. The synapse plays a crucial role in manipulating neuronal actions through medication and drugs. Neurotransmitters can have various effects in this space.

For example, let’s consider antidepressants. In cases of depression, there is often a deficiency of the neurotransmitter serotonin, which produces feelings of calm and happiness. When one neuron attempts to transmit serotonin to the next, the brain’s recycling system quickly removes it before the next neuron can receive enough to restore a happy mood. To address this, psychiatrists may prescribe selective serotonin reuptake inhibitors (SSRIs), which inhibit the reabsorption of serotonin, allowing it to remain in the synapse for longer. This extended presence enables the subsequent neuron to receive the message of a happier mood. It’s important to note that pills and ingested substances can have side effects since they circulate through the bloodstream and affect the entire body, not just the intended target.

To further explore the visual and interactive aspects of neuron anatomy, neuronal synapses, psychoactive drugs, and substance use disorder, I recommend referring to the Khan Academy lessons on YouTube (Overview of Neuron Structure and Function (Article) | Khan Academy, n.d.). By watching these videos, you can gain a clearer understanding of the concepts discussed in this essay and enhance your knowledge through visual illustrations and detailed explanations.

In summary, neurons are vital for neuronal communication in the brain. Their unique structure enables the transmission of electrical messages through dendrites, the cell body, and the axon. Myelination and the axon terminal facilitate the speedy conduction of messages, while the synapse allows for chemical transmission through neurotransmitters. Understanding the intricacies of neuron structure and communication sheds light on the functioning of our brains and the potential impact of medication and drugs on this complex system.

References

Lazzara, J. (2020, June 10). Biopsychology. Pressbooks. https://open.maricopa.edu/psy101/chapter/biopsychology/ 

Overview of neuron structure and function (article) | Khan Academy. (n.d.). Khan Academy. https://www.khanacademy.org/science/biology/human-biology/neuron-nervous-system/a/overview-of-neuron-structure-and-function 

Stangor, C. (2014, October 17). 4.1 The Neuron Is the Building Block of the Nervous System. Pressbooks. https://opentextbc.ca/introductiontopsychology/chapter/3-1-the-neuron-is-the-building-block-of-the-nervous-system/