The Brain
The brain controls thought, movement and body functions.
About this topic
The brain is the control centre of the nervous system. The cerebrum, divided into two hemispheres and lobes, handles thinking, memory, language and voluntary movement; the cerebellum coordinates balance and movement; the medulla controls breathing and heartbeat; the hypothalamus regulates temperature and hunger, and links to the pituitary gland.
The cerebral cortex has areas for vision, hearing, touch and speech. The brain contains about 86 billion neurons. Neuroplasticity lets it change with learning, and imaging like MRI studies its activity.
A famous case is Phineas Gage, a railway worker whose frontal lobe was damaged by an iron rod in 1848, changing his personality, showing that the frontal lobes affect behaviour. The hypothalamus controls temperature and hunger, the pituitary gland sits beneath it, and the medulla controls heartbeat and breathing. Different areas of the cerebral cortex handle vision, hearing, touch and movement.
Imaging methods like MRI and PET scans show brain activity, and strokes happen when blood supply to a region is blocked. The brain uses around 20 percent of the body's energy. A common myth is that we use only 10 percent of our brain; imaging shows we use all of it. Another is that the left and right brains make people either logical or creative; both sides work together.
Key ideas
- Cerebrum for thinking
- Cerebellum for balance
- Brainstem for breathing
Quick check
Use cases: where The Brain helps
- Homework: review the key idea behind The Brain before you start a problem set.
- Exam revision: use the quick check to test whether you can recall The Brain without notes.
- Visual learning: play with the interactive lab to see how The Brain changes when you adjust its inputs.
- Teaching a friend: explain The Brain in your own words, then compare your version with the key ideas.
Biology underpins medicine, farming, conservation and biotechnology.
Frequently asked questions
What is The Brain?
The brain controls thought, movement and body functions.
What will I learn in The Brain?
Cerebrum for thinking. Cerebellum for balance. Brainstem for breathing.
Is The Brain part of Biology?
Yes. It is one of 150 Biology topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.
Does the The Brain lab work on a phone or tablet?
Yes. The animation resizes to fit your screen and supports touch, so you can drag, tap and slide with your finger.
How should I study The Brain?
Read the summary and key ideas first, play with the interactive lab to see the idea in motion, then answer the quick check. If you get a question wrong, go back to the key idea it tests.
Do I need an account, and is my progress saved?
No account is needed. Marking a topic as learned is saved in your own browser, so it stays on that device and is not sent to a server.