Finding your way around
An annotated guide to the brain
Remember, many simple and complex psychological functions are mediated by multiple brain regions and – at the same time – a single brain area may control many psychological functions.

CC BY
Illustration by Bret Syfert
- Cortex: The thin, folded structure on the outside surface of the brain.
- Cerebral hemispheres: The two halves of the brain, each of which controls and receives information from the opposite side of the body.
- Pituitary gland: The ‘master gland’ of the body, which releases hormones that control growth, blood pressure, the stress response and the function of the sex organs.
- Substantia nigra: The ‘black substance’ contains cells that produce the neurotransmitter dopamine and the pigment melatonin, giving it a black appearance.
- Hypothalamus: The interface between the brain and pituitary gland. It controls the production and release of hormones.
- Spinal cord: A large bundle of millions of nerve fibres and neuronal cells, which carries information back and forth between the brain and the body.
- Medulla oblongata: Controls vital involuntary functions such as breathing and heart rate.
- Cerebellum: The ‘little brain’ that controls balance and coordinates movements. It’s normally required for learning motor skills, such as riding a bike, and is involved in thought processes.
- Cranial nerve nuclei: Clusters of neurons in the brain stem. Their axons form the cranial nerves.