Skip to main content

Verified by Psychology Today

Simple Imagery Exercises Can Change Nightmares

A recent study explores how imagery exercises can treat nightmares.

The majority of adults experience at least once yearly nightmares – intensely negative dreams that cause distress on awakening. 2-5% of adults experiences nightmares on a weekly basis, and this can be associated with severe distress and interfere with quality of life and psychological health.

Nightmares often have recurring themes, and it's thought that the nightmare story or 'script' is in some way stuck in our memory; the nightmare script replays in full anytime any element related to the theme is activated. For example, a nightmare of a tidal wave might be triggered by an initially innocuous dream of building a sandcastle – the sand element can trigger the whole nightmare script to replay.

Treatments for nightmares typically focus on activating the nightmare script in the waking state and then doing one of two things: 1) imagery rescripting, which is attempting to alter the script and change elements of the dream so that it becomes less distressing, or 2) imaginal exposure, which is attempting to decrease negative reactions to the nightmare over time.

Often, these two techniques are combined together, or combined with other therapeutic and psychoeducation techniques, such as keeping a sleep and dream diary and discussing waking life.

A recent study aimed to assess whether rescripting or exposure can ameliorate nightmares in the absence of any other therapeutic techniques, and to discern which factors predict treatment outcomes.

For example, the authors suspected that one factor which could predict patient outcomes would be whether they increase their ability to tolerate negative emotions over the course of treatment. In other words, is it simply that through working with the nightmare in waking life, the patient becomes more able to handle the negative emotions elicited by the nightmare?

Or is it that working with the nightmare in waking life instills more of a sense of control and mastery over the content of the nightmare?

The authors conducted a randomized controlled trial to compare patient outcomes following resripting or exposure treatments to a control condition without treatment (35, 33, and 36 patients per group). Patients had at least one nightmare per week, with recurring themes in their nightmares.

Treatments consisted of three weekly 60-minute one-on-one sessions. Both rescripting and exposure sessions began with a brief imagery exercise to reactivate the nightmare and its emotions.

After this exercise, rescripting treatment asked participants to imagine changing the nightmare script in their mind into a less distressing story and to continue imagining this 'rescripted' dream as vividly as possible for the remainder of the session. Exposure participants were simply asked to imagine their nightmare script as vividly as possible for the whole session.

Participants also rated their response to the following statements on a 0-100 scale at the beginning of the study, after each treatment session, and at the end of the study:

(1) When I think about my nightmares, I get emotional
(2) I think that I can predict the emotions elicited by my nightmares
(3) I think that I can control the emotions elicited by my nightmares
(4) I think that I can tolerate the emotions elicited by my nightmares
(5) I think that I am in control of the content of my nightmares
(6) How would you evaluate the quality of last night’s sleep?
(7) Nightmares have a negative influence on my daily functioning

Analyses could then be conducted to see which of these measures related to improvements in nightmare distress and nightmare frequency over the course of the treatment.

Further analysis showed that feeling able to control the content of the nightmare (item 5, 'mastery') specifically mediated improvements following the rescripting, but not the exposure treatment. Feeling mastery and agency over nightmares can be empowering for patients, and is clinically important because feeling helpless is one of the most common and debilitating symptoms of nightmares.

Becoming more able to tolerate the negative emotions elicited by nightmares (item 4) mediated outcomes from both treatments. Increasing a patient's ability to tolerate and sit with heir negative dreams in waking life thus seems to be key to treatment, and avoiding thinking about nightmares may impede recovery. Even in the absence of nightmares, studies have shown that suppressing negative thoughts in waking leads to an increase in distressing dreams of the suppressed thoughts (dream rebound – see previous blog here).

There did not seem to be any role of sleep quality in treatment outcomes, though the authors emphasize that the treatments were intentionally stripped of any sleep education. It's possible that combining treatments with sleep education could be more impactful in that improved sleep might further support recovery.

Overall, the study shows that being able to tolerate nightmare emotions and having a sense of control over nightmare content are both key changes that take place over the course of treatment, and thus may be used as targets for future research and therapy.


A. E. Kunze, J. Lancee, N. Morina, et al., Mediators of Change in Imagery Rescripting and Imaginal Exposure for Nightmares: Evidence From a Randomized Wait-List Controlled Trial, Behavior Therapy,