Ever wondered how your brain cells actually talk to each... Show more
Understanding Synaptic Transmission

How Neurons Communicate
Your brain is constantly buzzing with electrical and chemical activity. When a neuron gets activated, it switches from being negatively charged (at rest) to positively charged, creating an action potential - basically an electrical impulse that races down the neuron's axon.
But here's where it gets interesting: neurons don't actually touch each other. They're separated by tiny gaps called synapses, and this is where the magic of communication happens through synaptic transmission.
At the end of each neuron, you'll find little storage bubbles called synaptic vesicles packed with chemical messengers called neurotransmitters. When that electrical impulse arrives, these chemicals get released into the synapse gap, where they float across and bind to special receptors on the next neuron.
Key Point: Think of neurotransmitters like keys that only fit specific locks (receptors) - once they connect, they can either excite or calm down the receiving neuron.
This process only works in one direction because the sending equipment (vesicles) is only on the pre-synaptic side, whilst the receiving equipment (receptors) is only on the post-synaptic side. It's like having a one-way postal system that keeps your brain's messages organised and flowing in the right direction.
The receiving neuron then adds up all the excitatory signals (like noradrenaline, which make it more likely to fire) and inhibitory signals (like serotonin, which make it less likely to fire) through a process called summation. This determines whether it'll pass the message along or not.
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Understanding Synaptic Transmission
Ever wondered how your brain cells actually talk to each other? Synaptic transmission is the fascinating process that lets neurons communicate by sending chemical messages across tiny gaps, determining everything from your thoughts to your movements.

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How Neurons Communicate
Your brain is constantly buzzing with electrical and chemical activity. When a neuron gets activated, it switches from being negatively charged (at rest) to positively charged, creating an action potential - basically an electrical impulse that races down the neuron's axon.
But here's where it gets interesting: neurons don't actually touch each other. They're separated by tiny gaps called synapses, and this is where the magic of communication happens through synaptic transmission.
At the end of each neuron, you'll find little storage bubbles called synaptic vesicles packed with chemical messengers called neurotransmitters. When that electrical impulse arrives, these chemicals get released into the synapse gap, where they float across and bind to special receptors on the next neuron.
Key Point: Think of neurotransmitters like keys that only fit specific locks (receptors) - once they connect, they can either excite or calm down the receiving neuron.
This process only works in one direction because the sending equipment (vesicles) is only on the pre-synaptic side, whilst the receiving equipment (receptors) is only on the post-synaptic side. It's like having a one-way postal system that keeps your brain's messages organised and flowing in the right direction.
The receiving neuron then adds up all the excitatory signals (like noradrenaline, which make it more likely to fire) and inhibitory signals (like serotonin, which make it less likely to fire) through a process called summation. This determines whether it'll pass the message along or not.
We thought you’d never ask...
What is the Knowunity AI companion?
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
Where can I download the Knowunity app?
You can download the app from Google Play Store and Apple App Store.
Is Knowunity really free of charge?
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
Most popular content: Neurotransmitters
1Most popular content in Psychology
9Most popular content
9Can't find what you're looking for? Explore other subjects.
Students love us — and so will you.
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.