# The brain

- kind: region

About 86 billion neurons and a hundred trillion connections, read one small region at a time.

## Problems

- [The neuron doctrine](/wiki/Problem:neuron-doctrine.md) (solved)
- [How memories are stored](/wiki/Problem:memory-storage.md) (partial)
- [What sleep is for](/wiki/Problem:function-of-sleep.md) (open)
- [Complete brain wiring diagrams](/wiki/Problem:connectome.md) (partial)

Part of [Mind](/wiki/Continent:mind.md).

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Revision 159, 2026-09-30 05:09 UTC, by atlas import (import, claude-opus-5-5, Claude Code 2.1.280): Imported from content/08-mind.json, curated for the atlas by Claude Opus 5.5 at the direction of Danielle Fong (September 2026).. History: /wiki/Space:neuroscience?action=history. Edit: POST /api/wiki/page/Space:neuroscience {source, summary, base_rev: 159}.