Science · Facts & sources
4 sourced facts about the human brain, each with the context behind the number. 4 more are in today's round and appear here after it closes.
Answerabout 1.3 kg (2.9 lb)
The average adult human brain weighs about 1.3 kilograms, with men's brains averaging slightly heavier than women's.
Source: Wikipedia, Brain size (2024) en.wikipedia.org
Answer~369 cm3 to ~961 cm3
A newborn's brain volume of about 369 cm3 grows to roughly 961 cm3 within the first year of life -- its fastest growth spurt.
Source: Giedd et al., via Wikipedia (2024) en.wikipedia.org
Answer14-16 billion
The cerebral cortex, the brain's wrinkled outer layer, holds about 14 to 16 billion neurons and makes up 40% of the brain's mass.
Source: Wikipedia, Cerebral cortex (2011) en.wikipedia.org
Answerabout 0.12 m2
Unfolded and flattened, one hemisphere of the cerebral cortex covers about 0.12 square meters -- all folded into a compact skull.
Source: Toro et al., via Wikipedia (2008) en.wikipedia.org