neuron theory

biology

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July 1, 2026

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The neuron theory, proposed by Santiago Ramón y Cajal in 1889, posits that the nervous system is composed of individual, structurally independent units called neurons. These neurons communicate with each other across small gaps, rather than through direct physical continuity. This fundamental concept remains a guiding principle in neuroscience, even though it's not universally true.12

Neurons are the basic cells of the nervous system, responsible for processing and transmitting information via electrical and chemical signals. A typical neuron includes a cell body (soma) containing the nucleus, dendrites that receive signals, and an axon that transmits signals away from the cell body. Neurons communicate at synapses, using neurotransmitters to pass signals to other cells.3

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nervous system
The nerve cell
…hypothesis, now known as the neuron theory, each nerve cell communicates with others through contiguity rather than continuity. That is, communication between adjacent but separate cells must take place across the space and barriers separating them. It has since been proved that Cajal’s theory is not universally true, but his…
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…hypothesis, now known as the neuron theory, each nerve cell communicates with others through contiguity rather than continuity. That is, communication between adjacent but separate cells must take place across the space and barriers separating them. It has since been proved that Cajal’s theory is not universally true, but his…
Read More

Wilhelm His
…to the development of the neuron theory, which states that the neuron, or nerve cell, is the basic unit of the nervous system.
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…to the development of the neuron theory, which states that the neuron, or nerve cell, is the basic unit of the nervous system.
Read More