Action potential (spike)
A brief electrical pulse that an active neuron sends along its length, also called a spike or an action potential. In the lessons, each flash of light marks one.
See it in a lesson
Related terms
- Neuron
- A nerve cell. It receives signals from other cells and, when enough of them add up, sends a signal of its own.
- Synapse
- The junction where one neuron passes its signal to the next. The more synapses two cells share, the stronger the link between them.
- Neurotransmitter
- A chemical that a neuron releases at a synapse to pass its signal on. Some neurotransmitters excite the next cell, and others inhibit it.
- Excitation
- A signal that pushes the next neuron toward firing.
- Inhibition
- A signal that holds the next neuron back from firing. A network needs it to stay stable and precise.
- Acetylcholine
- The main excitatory neurotransmitter in a fly’s brain. In the lessons, cells that release it excite the cells they connect to.
- GABA
- An inhibitory neurotransmitter, in flies and in people. In the lessons, cells that release GABA quiet the cells they connect to.
- Neural circuit
- A group of neurons wired together to do one job, such as recognizing a smell or setting off a jump.
- Connectome
- A complete wiring diagram of a nervous system: every neuron and every synapse between them. The lessons run on the connectome of one real fruit fly.