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.
