## TL;DR

The human brain (~1.4 kg) is the most complex known object in the universe with ~86 billion neurons and ~100 trillion synapses. Regions: cerebrum (thinking, sensory, motor), cerebellum (coordination), brainstem (life support), limbic system (emotion, memory). Consciousness remains one of science's greatest mysteries.

## Core Explanation

Cerebral cortex: folded outer layer, 4 lobes (frontal: planning/personality, parietal: touch/spatial, temporal: hearing/memory, occipital: vision). Broca's area (speech production), Wernicke's area (comprehension). Left brain: language, logic. Right brain: spatial, creative (oversimplified — both sides collaborate). Corpus callosum: connects hemispheres. Brain plasticity: rewires throughout life (neuroplasticity).

## Further Reading

- [Principles of Neural Science (6th Ed, Kandel et al.)](https://www.mheducation.com/highered/product/principles-neural-science-kandel-koester-mack-siegelbaum/9781259642234.html)