They're incredible. Amazing. Magical. But perhaps the most fantastic thing about lucid dreams – in which the dreamer becomes aware they're dreaming – is how realistic they seem.
Sadly, only about half of us ever experience lucid dreams in our lives, and efforts to trigger the phenomenon have delivered mixed results. But a study published in 2018 revealed one of the most effective ways of inducing lucid dreaming yet.
Building on their own previous research, researchers at the University of Wisconsin–Madison and the Lucidity Institute in Hawaii wanted to investigate how chemicals called acetylcholinesterase inhibitors (AChEls) might promote lucid dreaming.
The neurotransmitter acetylcholine is thought to help modulate REM sleep, and AChEls help this compound to aggregate in the brain by inhibiting an enzyme (called acetylcholinesterase) that inactivates acetylcholine.
As it happens, a common drug used to treat memory decline in Alzheimer's disease – known as galantamine – is a fast-acting AChEI with only mild side effects, so researchers recruited 121 participants to see what effect the drug had on their ability to have and recall lucid dreams.
It's worth pointing out these volunteers weren't just everyday people, but enthusiasts with an established interest in lucid dreams, who also had undertaken training with lucid dream induction protocols (including what is known as the MILD technique).
When this cognitive training was combined with galantamine, lucid stuff started to happen.
Over three consecutive nights, participants took increasing doses of the drug, starting with a placebo, then 4 mg, then 8 mg on the final night.
Each night, participants woke 4.5 hours after lights out, practiced their dream induction techniques, ingested their capsules, and returned to sleep.
The combination of the induction technique paired with the Alzheimer's medication looks to indeed help trigger lucid dreams, and the higher dosage delivered a stronger result.
While taking the 'active' placebo (0 mg of galantamine but still using the MILD technique), 14 percent of participants reported a lucid dream, but this increased to 27 percent when 4 mg was consumed and rose to 42 percent with an 8 mg dose.
"This combined protocol resulted in a total of 69 out of 121 participants (57 percent) successfully having a lucid dream on at least one out of two nights on an active dose of galantamine," the researchers wrote in their 2018 paper.
"This protocol is one of the most effective methods for inducing lucid dreams known to-date, and holds promise for making lucid dreaming available to a wider population."
That's important because in addition to helping people enjoy fantastic dreams where they can help control what happens, the research could also help explain the links between lucid dreams and consciousness and help people to confront their fears and process trauma while safely asleep.
"This new method finally has the success rate we need to be able to properly do research on lucid dreaming," psychologist Denholm Aspy from the University of Adelaide in Australia, who wasn't involved in the study, explained to New Scientist at the time.
Until we know more about the safety of this technique, nobody should be experimenting with galantamine on their own. But once more research is done, these findings may ultimately beckon an almost limitless world of imaginary fun and adventure.
"As I ran my hand along a brick wall… I could feel the coarse texture and the outline of individual bricks," said one of the team, cognitive neuroscientist Benjamin Baird from the University of Wisconsin–Madison, recalling his own experience of galantamine.
"It's like going into the holodeck in Star Trek where you can have any imaginable experience you choose."
The findings were reported in PLOS One.
A version of this article was first published in August 2018.