The lifestyle imbalance

One of the areas of the brain that’s most active during dreaming is the amygdala - the part of the brain associated with the survival instinct and the fight-or-flight response.

One theory suggests dreams may be the brain’s way of getting you ready to deal with a threat. Fortunately, the brainstem sends out nerve signals during REM sleep that relax your muscles. That way you don’t try to run or punch in your sleep.

One theory for why we dream is that it helps facilitate our creative tendencies. 

Without the logic filter, you might normally use in your waking life that can restrict your creative flow, your thoughts and ideas have no restrictions when you’re sleeping.

• One theory is that dreaming helps with sleep's memory-processing function. During sleep, the brain sorts through information gathered during the day, then decides what to keep and what connections to make between new information.
• Another theory is that dreams help with emotional processing by removing some emotional associations.
• Dreams may provide a safe way of testing the brain's reactions to negative events.
• Or dreams are just the by-product of a brain starved of external input.

It is not genetics that determines whether you are an 'early riser' or an 'evening owl'. It is mostly habitual and environmental.

Early research found a connection between night owls and developing schizophrenia later in life. On average, owls also have lower wellbeing and are more likely to develop depression. It could be that owls are experiencing constant jet lag, which may put their bodies under stress.