Neurons are electrically excitable cells that transmit signals throughout your body, and right now, billions of them are firing in patterns so intricate that nobody fully understands how they generate consciousness [1]. But we do know how they work mechanistically.
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Neurons are electrically excitable cells that transmit signals throughout your body, and right now, billions of them are firing in patterns so intricate that nobody fully understands how they generate consciousness [1]. But we do know how they work mechanistically. And that story begins with the neuron's architecture.
A typical neuron is comprised of a soma, or cell body [1]. From that cell body, two types of structures branch outward, each with its own job. Dendrites are branches that receive messages from other nerve cells, acting like antennae [2]. They're the neuron's listening equipment. On the other end, axons carry outgoing messages from the cell body to other cells, such as a nearby neuron or muscle cell [2]. So information flows in through the dendrites and out through the axon. At the very tip of the axon sit axon terminals, also called terminal buttons, which are responsible for transmitting signals to other neurons [3].
But here's the part that really matters: the gap between neurons. The synapse is the junction between the axon of one neuron and the dendrite of another, often including a space called the synaptic cleft [4]. That tiny gap is where the real magic of communication happens. Neurotransmission is the process by which neurons pass information to each other at synapses [5].
So how do they actually cross that gap? Neurotransmitters are chemicals stored in vesicles within the axon terminal and are released into the synapse to carry signals [6]. A neurotransmitter is a chemical released from a neuron following an action potential—that electrical impulse traveling down the axon—which then travels across the synapse to excite or inhibit the target neuron [4]. The sending neuron fires electrically. Then it switches to chemistry to send its message across the gap. Then the receiving neuron converts that chemistry back into electricity.
The body uses several key neurotransmitters to fine-tune this process [7]. Acetylcholine, dopamine, and serotonin each carry different kinds of information—controlling muscle movement, motivation, mood, and much more [7]. Each one is like a different voice in a vast conversation happening at trillions of synapses every second.
This foundation explains how individual neurons talk to each other. The next layer—how those conversations coordinate across entire brain regions—reveals how the brain actually thinks.
But a brain region in isolation tells only half the story. The real power of your brain emerges when you pull back and see the whole network at work.
Think of it this way: individual neurons fire, but the brain works as a team. Structure and function aren't separate things — they're two sides of the same coin. The brain operates through a network approach, where interconnected regions collectively support every behavior you produce, from moving your hand to remembering a face [8]. The key insight is this: the network itself, rather than any single brain region, is the true unit for understanding how your brain supports behavior [8]. When you read a sentence, recall a memory, or feel afraid, you're not activating one isolated brain area. Instead, processes supporting behavior are implemented by the dynamic interaction and recruitment of multiple brain areas into multi-region assemblies [8].
Scientists have mapped several of these large-scale networks. The default mode network and the central executive network are examples of these coordinated systems [9]. These networks don't operate in isolation — they communicate constantly, reshaping themselves based on what you're doing and learning.
Here's where it gets really interesting. Your brain's architecture isn't fixed. Neuroimaging studies have focused on localizing specific brain regions differentially activated during cognitive tasks such as reading, calculating, and musical processing [10], but what's emerged is something more dynamic. Higher cognitive functions, including attention, memory, and planning, take place in the cerebral cortex and are generally related to conscious perceptions [11]. The temporal lobes specifically are involved in short-term memory, speech, musical rhythm, and some degree of smell recognition [12]. Meanwhile, deeper structures like the midbrain contain neuron clusters and neural pathways that facilitate functions like hearing and movement [12].
But here's the part that bends your mind: your brain rewires itself constantly through experience. This process, called neuroplasticity, means the structure you're born with isn't your destiny. Cognitive training can enhance resting-state brain networks, particularly the default mode network and the central executive network, leading to greater connectivity and improved white matter integrity [13]. Even engaging in artistic practice creates changes in neural network connections and increases cognitive flexibility [14].
Yet aging complicates this picture. Significant negative plasticity, affecting brain function, can occur with aging even in the absence of disease pathology [9]. The brain operates as an interconnected network where different regions coordinate responses and behaviors, with neural pathways facilitating communication between sensory input, emotional reactions, and rational thought [15]. That coordination is what makes you you — not one region, but the ceaseless conversation between them all.
Thanks for listening to this VocaCast briefing. Until next time.