Final answer:
When Dement's research subjects were in the REM-interruption phase, they showed behavioral changes associated with REM sleep behavior disorder (RBD). This includes exhibiting high levels of physical activity during REM sleep and engaging in behaviors like kicking, punching, scratching, yelling, and behaving like a frightened or attacked animal. These behaviors can cause harm to oneself or sleeping partners.
Step-by-step explanation:
When Dement's research subjects were in the REM-interruption phase of the study, they showed behavioral changes associated with REM sleep behavior disorder (RBD). This disorder occurs when the muscle paralysis typically experienced during REM sleep does not occur. As a result, individuals with RBD exhibit high levels of physical activity during REM sleep, such as kicking, punching, scratching, yelling, and behaving like a frightened or attacked animal. These behaviors can cause injury to themselves or their sleeping partners. However, it is important to note that affected individuals have no memory of these behaviors.