Spinal Cord Injuries
Spinal cord injuries interrupt messages between the brain and body. They may cause a
person to lose the ability to feel or move parts of the body. This is called paralysis.
Whether paralysis occurs—and what parts of the body are affected if it does—depend on
the location and seriousness of the injury. In addition to car crashes and sports injuries,
diving accidents are a common cause of spinal cord injuries.
Some people recover from spinal cord injuries. However, many people are paralyzed for life.
Thanks to the work of Christopher Reeve (Figure20.36), more research is being done on
spinal cord injuries now than ever before. For example, scientists are trying to discover ways
to regrow damaged spinal cord neurons.
Figure 20.36: FormerSupermanstar, Christopher Reeve, was paralyzed from the neck down
in a fall from a horse; the injury crushed his spinal cord so his brain could no longer com-
municate with his body. ( 35 )
Dangers of Alcohol and Other Drugs
Adrugis any chemical substance that affects the body or brain. Some drugs are medicines
(Figure20.37). Although these drugs are helpful when used properly, they can be misused
like any other drugs. Drugs that aren’t medicines include both legal and illegal drugs.
Examples of legal drugs are alcohol and caffeine. Although these drugs can be used legally
by adults, they can still do harm. Examples of illegal drugs include marijuana and cocaine.