Nightmare Review

Written by remrama

As I write/think more about lucid dreaming (LD) grants, I’m more excited about the possibility of using LD for therapy (lucid dreming therapy; LDT). But I’m definitely ignorant on the nightmare literature, so this very recent review seems appropriate. It seems to be fairly comprehensive, and also has a clear clinical focus.

Gieselmann et al., 2019, Journal of Sleep Research

Great read! As someone familiar with dreams but not at all with nightmares, and wanting to get an understanding of the clinical situation, this was perfect. I think I picked up lots of useful things to highlight for the grant I’m writing, and also many ideas for future work (although I presume some of it’s been done I just need to search for it).

Nightmares (NMs) are tough to define. They make an important distinction between NM frequency and NM distress, and the latter is more associated with psychiatric symptoms. Another distinction is that between NMs and night terrors: while NMs involve immediate/clear awakenings and vivid recall of the dream, night terrors involve a “hazier” awakening with fragmented recall of a negative experience (this distinction seems a bit unclear to me). Another interesting comparison is between “posttraumatic” and “idiopathic” NMS: posttraumatic NMs are more episodic replays of waking events, and these are considered more severe on a variety of NM measures, with more negative waking consequences. Idiopathic NMs are the more strange/fantastical negative dream experiences. Then moving to NM disorder, where severe NM disorder is when they occur nightly, and moderate NM disorder is classified as weekly NMs.

It was nice how the aetiology (and resulting treatment approaches) was broken down into different mechanisms, such as neural circuitry and state/trait features.Also there was a clear distinction between hyperarousal and fear extinction contributions to NM disorder. I found myself focusing more on the fear extinction aspect since it is more relevant to ongoing work in our lab, and it seemed like there was lots of space for new studies to be ran based on these ideas. The maain idea here was that normal sleep aids in fear extinction through associating fearful memories with other non-fear memories, and this doesn’t occur in situations of NMs. This is a neat idea, though it’s unclear to me just through this review whether that has empirical support or not. There were 3 main references I’ll have to dig into supporting an “affect network dysfunction model” (AND; here, here and here), which will probably answer that question. This model makes specific neural predictions that I think haven’t been tested yet?? From the article: “The theory formulated above that impaired fear extinction and elevated hyperarousal are necessary to elicit nightmares remains hypothetical and should be investigated empirically.”

Lastly I wanna point out some important things I should extract and highlight in the current grant proposal I’m writing. There were a number of important issues brough up about NM disorder, and also a bit about lucid dreaming therapy (LDT) that I could point out.