Q: Why do we dream?

A: There are many theories about why we dream, but no one really knows for sure.  Some say dreams have no purpose or meaning, while others say dreams are necessary for emotional and physical health.

According to some current theories, dreaming is:

• A form of memory processing that aids in the consolidation of learning
• A means by which our minds work through difficult, complicated thoughts, emotions and experiences
• The way our brains respond to biochemical changes and electrical impulses

Do you ever wonder about nightmares, specifically? They are a hallmark symptom of post-traumatic stress disorder (PTSD). Depression and anxiety often are accompanied by nightmares, with people who are depressed or anxious are more likely to have stressful, disturbing or frightening dreams, sometimes in the form of recurring dreams.

If people walk around or move freely while dreaming, they may have REM behavior disorder (RBD), which is a condition where the normal paralysis that occurs during REM sleep doesn’t occur. People with this condition can move during this sleep phase, and often act out physically in reaction to their dreams, which can lead to injury to the sleeper or a bed partner.

— Sleep psychologist Michelle Drerup, PsyD