Final answer:
In a lucid dream, an individual becomes aware they are dreaming and can control the dream. The concept of lucid dreaming has been of interest to psychologists such as Freud and Hobson and may involve the sleep hormone melatonin.
Step-by-step explanation:
In a lucid dream, a person becomes aware of the fact that they are dreaming and as such, they can control the dream's content. This phenomenon has caught the interest of many researchers and psychologists, including Sigmund Freud, who differentiated between the manifest content and the latent content of dreams. Where manifest content represents the actual storyline of the dream, latent content is thought to hold the hidden psychological meaning. Additionally, lucid dreaming has been studied about our waking lives by theorists like Alan Hobson, who proposed the activation-synthesis theory, describing dreams as our brain's attempt to make sense of random neural activity during REM sleep. Moreover, lucid dreams may even be associated with higher levels of melatonin, a hormone influential in regulating sleep-wake cycles, suggesting a biological component to these experiences.