Question: Can dreams be a cause of mental illness or be why some people have unexplainable fears

Alex Reid answered on 13 Nov 2018: last edited 13 Nov 2018 3:45 pm

Hi thank you for the great question. We are not presently sure why you dream, but our best (educated) guess is that dreams have no ‘function’ of their own like a heart or lung. They are most likely a by-product of other cognitive processes in sleep, such as your memories being formed and reshaped by your brain. This is called ‘memory consolidation’, and when different brain regions talk to each other dreams might be your mind ‘overhearing’ this conversation and trying to make sense of it. It follows that, as a probable by-product, dreams might not directly cause mental health issues. However, if you have a strong fear or phobia, you might pay attention to these things more when awake, and then selectively process memories relating to these more during sleep. As such phobic memories might be expressed more in dream content compared to someone without that phobia. This might be particularly the case in Rapid Eye Movement (REM) sleep, as this is the stage associated the most with both dreaming and emotional memory processing. While there might not be a causal link between dreams and mental health issues (or at least one that I am aware of) this does not mean that dreams are not interesting or useful to study. There is a close link between sleep and mental health complaints, and some disorders, such as Post Traumatic Stress Disorder (PTSD), are often accompanied by terrible nightmares. Also, despite not having a ‘function’ (like a heart or liver) dreams can also be used successfully in some therapies where people might talk with a counselor about their dream content. Dreams can sometimes reveal insights into issues that you might not be so aware of when you are awake and this has therapeutic applications.