Your brain processes information through electrical and chemical signals that...
Psychology334 views·Updated 2 Sept 2026·2 pagesUnderstanding Synaptic Transmission: Structure and Function
Demetra@demetra_21
1
of 2
Action Potential and Neural Firing
Think of neurons like tiny electrical switches that can flip from "off" to "on" in milliseconds. At rest, the inside of a neuron is negatively charged compared to the outside, but when stimulated, it rapidly flips to become positively charged through a process called depolarisation.
This electrical flip creates an action potential - basically an electrical impulse that races down the neuron's axon like electricity through a wire. The brilliant thing is that this only happens when the stimulus reaches a specific threshold - it's an all-or-nothing response that fires at the same intensity every time.
If the threshold isn't reached, nothing happens at all. Once it does fire, the neuron quickly returns to its resting state through repolarisation, ready to fire again when needed.
Key Point: The action potential is like a light switch - it's either completely on or completely off, never halfway!
2
of 2
Synaptic Transmission and Chemical Messengers
When that electrical impulse reaches the end of a neuron, something amazing happens - it triggers the release of chemical messengers called neurotransmitters. These chemicals are stored in tiny sacs called vesicles that dump their contents into the gap between neurons (the synaptic cleft) through a process called exocytosis.
The neurotransmitters then drift across this microscopic gap and bind to specific receptors on the next neuron, like keys fitting into locks. Depending on which neurotransmitter it is, this binding can either make the next neuron more likely to fire (excitatory) or less likely (inhibitory).
After doing their job, neurotransmitters are either broken down by enzymes or recycled back into the original neuron through reuptake. Key players include GABA (your brain's brake pedal for anxiety), dopamine (linked to pleasure and addiction), glutamate (essential for learning), and serotonin (your mood booster that also controls sleep).
Remember: Each neurotransmitter has its own specific job - like having different tools for different tasks in your brain's toolkit!
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Psychology334 views·Updated 2 Sept 2026·2 pagesUnderstanding Synaptic Transmission: Structure and Function
Demetra@demetra_21
Your brain processes information through electrical and chemical signals that jump between neurons. Understanding how synaptic transmission works is crucial for grasping how everything from your thoughts to your emotions actually happen at a biological level.
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of 2
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Action Potential and Neural Firing
Think of neurons like tiny electrical switches that can flip from "off" to "on" in milliseconds. At rest, the inside of a neuron is negatively charged compared to the outside, but when stimulated, it rapidly flips to become positively charged through a process called depolarisation.
This electrical flip creates an action potential - basically an electrical impulse that races down the neuron's axon like electricity through a wire. The brilliant thing is that this only happens when the stimulus reaches a specific threshold - it's an all-or-nothing response that fires at the same intensity every time.
If the threshold isn't reached, nothing happens at all. Once it does fire, the neuron quickly returns to its resting state through repolarisation, ready to fire again when needed.
Key Point: The action potential is like a light switch - it's either completely on or completely off, never halfway!
2
of 2Sign up to see the content. It's free!
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Synaptic Transmission and Chemical Messengers
When that electrical impulse reaches the end of a neuron, something amazing happens - it triggers the release of chemical messengers called neurotransmitters. These chemicals are stored in tiny sacs called vesicles that dump their contents into the gap between neurons (the synaptic cleft) through a process called exocytosis.
The neurotransmitters then drift across this microscopic gap and bind to specific receptors on the next neuron, like keys fitting into locks. Depending on which neurotransmitter it is, this binding can either make the next neuron more likely to fire (excitatory) or less likely (inhibitory).
After doing their job, neurotransmitters are either broken down by enzymes or recycled back into the original neuron through reuptake. Key players include GABA (your brain's brake pedal for anxiety), dopamine (linked to pleasure and addiction), glutamate (essential for learning), and serotonin (your mood booster that also controls sleep).
Remember: Each neurotransmitter has its own specific job - like having different tools for different tasks in your brain's toolkit!
We thought you’d never ask...
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.
You can download the app from Google Play Store and Apple App Store.
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