How many neurons are in a human brain?

Q: How many neurons are in a human brain?

86 billion neurons (86,000,000,000). 86 billion, with about 100 trillion connections between them. More connections than stars in the Milky Way. Source: Herculano-Houzel, 2009

86 billion

neurons

86,000,000,000 exactly, give or take

86 billion, with about 100 trillion connections between them. More connections than stars in the Milky Way.SOURCEHerculano-Houzel, 2009

Scale check: 86 billion is roughly more than everyone alive today.

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