How a neuron cell is working
A neuron has got many thousand dendrites.
Impulse flow: dendrites ⇒ cell ⇒ axon
presynaptic: dendrites of another neuron.
postsynaptic: from axon to dendrites of a second neuron.
We have a thousand trillion synapses in our brain.
The message that travels in the axon is electrical, but most synapses transform it into a chemical one. The end of the axon, the “terminal button” near the synapse, contains vesicles, tiny pockets filled with molecules called “neurotransmitters” (glutamate, for example). When the electrical signal reaches the terminal button of an axon, the vesicles open, and the molecules flow into the synaptic space that separates the two neurons. This is why we call these molecules neurotransmitters: they transmit a message from one neuron to the next. A moment after they are released from the presynaptic terminal, the molecules attach themselves to the membrane of the second, postsynaptic neuron, at particular points called “receptors.” Neurotransmitters are to receptors like keys are to locks: they literally open doors in the membrane of the postsynaptic neuron. Ions, positively or negatively charged atoms, pour into those open channels and generate an electric current within the postsynaptic neuron. The cycle is complete: the message went from electrical to chemical, then from chemical back to electrical, and in the process, it crossed the space between the two neurons.
(p.85)
Neurons that fire together, wire together
this is what happens when we learn. We get more neurons to fire at the same time so the signal gets stronger.
see also
Tags: neuroscience science
Superlink: 050 🧠Neuroscience
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Erstellt: 27-04-22 10:32