Dreams: The Mysteries of Sleep

Nightmares flash across our minds, vivid and frightening, and our hearts pound. And unlike most dreams, nightmares often awaken us. Some distinctive moment of fear or panic jolts us into consciousness and out of the anxious dreamscape.

Young children experience the most frequent nightmares, and most will grow out of them. Still, everyone has a nightmare now and then, and some have them often enough to be diagnosed with dream disorder. A nightmare theme may recur again and again, known as a repeating nightmare. Nightmares are also a common symptom of post-traumatic stress disorder (PTSD).

It's thought that stress or trauma can trigger nightmares. But what makes them startling enough to wake us out of the depths of sleep? Two different brain regions could provide some answers.

REM sleep, named for the rapid eye movement that is the hallmark of this phase of sleep, provides the setting for the most vivid of dreams and of nightmares. It's a sleep stage that is deep yet active. During REM, our limbic system, the brain's centre of emotion, lights up with activity. At the same time, our prefrontal cortex, the region of reason and logic, dozes. So, you have wide-awake emotion while reason is asleep at the wheel. No wonder you can dream yourself into the most outrageous situations and just shrug it off. In the case of nightmares, though, your mind can take you into some pretty terrifying territory.

Aside from stress or trauma, nightmares may arise from:

• eating right before going to sleep
• fever
• grief
• certain medications or withdrawal from a drug
• drinking too much alcohol
• sleep or breathing disorders (e.g., sleep apnea)

Anti-anxiety and anti-depressant medications are sometimes prescribed for people dealing with nightmares, especially when a nightmare is due to a medical condition (e.g., post-traumatic stress disorder). Hypnosis and therapy provide relief to some people. You may sleep more soundly with some of these self-care tips:

• Follow a regular fitness routine. Steady levels of activity could help you fall asleep more quickly and more soundly.
• Practice relaxation techniques to reduce muscle tension.
• Avoid food or caffeine too near to your bedtime.
• Talk to friends or family about your nightmares.
• Follow a good sleeping routine. Go to bed at the same time every day and wake up at the same time every day.