But are they really a good idea? Some scientists say it will soon be possible to connect a sick person’s head to a healthy body. Few proposals have caused so much controversy.
2030 forecast: human head transplants

Glossary
Laboratory - A room for scientific experiments or research.
Neurosurgeon - A surgeon specialising in the brain, spinal cord and nervous system.
Transplants - When a part of one individual's body is given to another in surgery.
Controversial - Causing a lot of angry public discussion and disagreement.
Unethical - Not morally right.
Spinal cord - The bundle of nerves enclosed in the spine, connecting parts of the body to the brain.
Paralysed - Unable to move.
Chronic - A condition which recurs over time, or lasts for several years.
Clone - To create an exact genetic copy of an organism or cell.