We’ve all experienced it: you wake up in the middle of the night in your dark room, heart pounding, looking around for the awful threat you’ve escaped… you just had a nightmare! One to two nightmares a week is considered normal in kids, and we still occasionally have them as adults; however, frequent adult nightmares experienced after maturity can be a reaction to severe traumas and/or a symptom of psychological disorders. Of course, nightmares in adulthood can also be a normal reaction to stress or recent traumatic events in your life. The brain continues to work on real-life problems as you sleep, so sometimes nightmares are the result of your brain processing troubling issues in your dreams. However, if you have frequent adult nightmares which interfere with your sleep, ability to work, and quality of life, it could fit the symptoms of nightmare disorder.

Formerly called dream anxiety disorder, nightmare disorder is catalogued 307.47 in the DSM-IV and is a common component of other sleep disorders and trauma-related conditions such as PTSD. Nightmares in adults are only classified as nightmare disorder if the bad dreams are frequent enough to interfere with a person’s waking activities and enjoyment of life. People who have experienced a traumatic event will often relive the scenario in a recurrent nightmare, which is one of the common symptoms associated with PTSD and other anxiety disorders. If you or someone you know suffers from recurrent or frequent bad dreams, there are effective therapeutic ways to deal with them that do not involve taking psychiatric medications or even sleeping pills. Image rehearsal therapy can help you envision and act out a more positive end to your bad dreams while you’re comfortably awake. You can also use lucid dreaming methods to confront threats during your nightmares and transform these dreams into positive experiences.

Cognitive therapies like those above are effective for adult nightmares that stem from trauma, stress and anxiety. On the other hand, nightmare disorder can also accompany deep-seated personality disorders resulting from serious traumas or chemical imbalances in the brain. Recent research has revealed that dissociative disorder and borderline personality disorder are two conditions that may include frequent nightmares in adults as a symptom. This is partly because these two disorders often disrupt the sufferer’s quality and duration of sleep.

Dissociative disorder can be a reaction to extreme trauma in which a sufferer closes him or herself off from the memories and experiences associated with the trauma. It can be accompanied by nightmare disorder if the dissociation is a defense mechanism against recalling a traumatic event. In this case, elements of the sufferer’s trauma might play themselves out in recurring nightmares. People with dissociative disorder are at higher risk for suicide and self-mutilation, and may also have borderline personality disorder.

Nightmare disorder may also be a component of extreme borderline personality disorder: people with severe BPD experience altered stages of sleep, with much heavier Stage 1 (NREM) sleep and lighter Stage 4 (deep) sleep. So, in the stages of sleep when the brain would normally be at its most inactive, the brains of people who have BPD show heightened brain activity, which can cause unusually vivid dreams in someone with BPD. Like dissociative disorder, if borderline personality disorder is a defense mechanism to guard someone against a past trauma, it makes sense that most of these dreams might replicate traumatic content that the person is unable to acknowledge in waking life.

There are other disruptive dream-related disorders that don’t incorporate what we would call nightmares at all. One of these is REM sleep behavior disorder, in which your brain fails to send you into a state of sleep paralysis (REM atonia) before it initiates REM sleep. The result is that sufferers act out their dreams, risking injury to themselves or a sleeping partner. REM sleep behavior disorder is more common in men than women, and more frequent in middle aged and older people. Sufferers’ dreams are often violent or action-filled, but don’t necessarily have to be scary or distressing. However, REM sleep behavior disorder is worth going to a doctor about, as it can indicate degenerative neurological disorders such as narcolepsy, primary dementia and Parkinson’s disease in about 50% of people affected. Lesions in the brain or brain stem, or thalamic abnormalities can also cause REM sleep disorder.

Finally, night terrors — while categorically different from nightmares— can also disrupt sleep in both children and adults. Night terrors occur naturally in about 1-6% of children, and are defined as episodes of extreme terror and panic in the early stages of sleep. They can be characterized by writhing movements and intense vocalizations which some people have described as “bloodcurdling screams”. It can be hard to rouse someone from night terrors, and they may have trouble remembering the dream’s content even though they feel the same level of distress as in nightmares. Adult night terrors can be a sign of psychopathologies such as affective disorder or substance abuse, or they might be a result of sleep disruption resulting from restless leg syndrome or sleep apnea.

On the whole, frequent adult nightmares don’t have to be the result of a psychological disorder requiring medication. Sometimes frequent nightmares in adults are the product of unresolved conflicts, stress and anxiety, or poor health habits. You can usually reduce frequent bad dreams through cognitive therapies and by improving your diet, being regularly active, and maintaining a regular sleep schedule. However, sometimes regular adult nightmares are a sign of deeper psychological issues, and you should always consult a doctor or psychologist if you have persistent nightmares that interfere with your quality of life. Our bodies and brains have evolved to give us warning signals when something’s not right with our physical or emotional health, and our dreams are one such signal; all you have to do is listen to them.