The Short Answer: What Is a Brain Circuit?

  • Published6 Jun 2019
  • Source BrainFacts/SfN

Neuroscientist Nick Spitzer explains how the billions of neurons in the brain give rise to brain circuits.



Nick Spitzer: My Name is Nick Spitzer, I’m the Atkinson Family Distinguished Professor at the University of California San Diego.

Screen Text: What is a circuit?

Nick Spitzer: So, circuits are connections of neurons. We have 86 billion neurons in our brains, and they’re connected to each other, each neuron has about 10,000 inputs, connections. So, the circuit is the path that the electrical activity follows as it moves from one nerve cell to the next, to the next, to the next. And perhaps at the end, to an effector organ, such as a muscle, that would cause contraction, and ultimately, in a coordinated way, behavior.

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