Do you dream when you are in a coma?

As a neuroscientist with a focus on the study of consciousness and the brain, I can tell you that the question of whether a person dreams during a coma is a complex one. A coma is a state of unconsciousness where a person is unresponsive to their environment and cannot be awakened. While it's difficult to study the brain activity of comatose patients directly, some research suggests that certain brain patterns associated with dreaming, such as rapid eye movement (REM), may not be present or may be significantly altered.

However, the absence of typical REM sleep does not necessarily mean that dreaming is impossible. Some studies have indicated that patients who have recovered from a coma have reported experiences that could be interpreted as dreams. But these reports are anecdotal and not consistent across all patients.

It's also important to note that dreaming is thought to serve various cognitive functions, and the brain activity during a coma may be too disrupted to support the complex processes involved in dreaming. Therefore, while it's not possible to say definitively that a person does not dream in a coma, the evidence suggests that if dreaming occurs, it is likely to be different from the dreaming that takes place during a normal sleep cycle.

They do not respond to touch, sound or pain, and cannot be awakened. Their brains often show no signs of the normal sleep-wakefulness cycle, which means they are unlikely to be dreaming. Yet many people who have recovered from comas report dreams into which something of the outside world penetrated.