In 2008, Isaac Katz, a civil service officer, passed away just before reaching his 78th birthday. He had been struggling with cardiovascular problems for some time. His son, Arnon Katz, now a 47-year-old tech entrepreneur, was beside himself with grief, and frustrated by the fact that he would never speak to his father again.
At the time, the younger Katz had been training himself to lucid dream—a phenomenon in which the dreamer becomes aware they are dreaming and can potentially control their actions as well as the content and context of the dream. But despite keeping a dream journal and diligently practicing other techniques, hadn't had any success. All that changed, though, a year after his father’s death.
Katz recalled in a recent phone interview that he was mid-dream when his mother suddenly warned him in a voiceover, "Hey, you're dreaming right now, so don't take what your father is saying too seriously."
Katz told me, "Suddenly everything slowed down and became incredibly vivid and real. I knew I was dreaming, but I felt I was with my father and could choose what to say as if I was awake. When I woke up, I realized that our brains are capable of creating an entire reality apart from waking life." Many other lucid dreamers have said something similar.
Katz said the experience allowed him to finally "close the circle." The frustration he felt in the year following his father's death was gone.
Lucid dreams are generally understood to occur exclusively during REM, the final phase of the sleep cycle that is most closely related to wakefulness and the one generally associated with dreams. Research on the prevalence of lucid dreamers suggests that if you've never had a lucid dream, you may be in the minority.
In a 2004 study of psychology undergrads in Germany, 82 percent of participants reported having experienced a lucid dream at least once. In Japan in 2008, 47 percent of surveyed undergrads had experienced a lucid dream, with 19 percent of participants lucid dreaming frequently (at least once a month). A recent Brazilian study found that 77 percent of those surveyed had experienced a lucid dream.
Another German study attempted to understand lucid dreaming as it relates to age and surveyed students between the ages of 6 and 19. They found that by age 19, more than 50 percent of the sample had experienced at least one lucid dream, with the frequentness of lucid dreams decreasing with age. In a less scientific survey, I was amazed at the number of friends and family members I discovered over the course of writing this article who have lucid dreams.
While it might be possible to broadly estimate how many people have experienced a singular lucid dream, it’s perhaps more difficult to determine how many people are deliberately doing so. Dr. Daniel Erlacher, a sleep researcher and lecturer of sports sciences at the University of Bern who contributed to two of the studies cited above, told me that when we talk about very frequent lucid dreamers—those who have multiple lucid dreams per week—the figure drops to around one percent. These are the people researchers want to get into their labs.
But we needn’t look any further than Facebook pages, blogs, and websites to find a community of passionate lucid dreamers and lucid dreamers in training. Rebecca Turner, now a 30-year-old writer from Kent, England, says she trained herself to lucid dream when she was 14 and has been doing it ever since—up to several nights per week, depending on how much time she devotes to “lucidity practice.” The Facebook page for Turner’s site, World of Lucid Dreaming, has more than 200,000 followers, and on April 12th Turner and some other lucid dreamers are organizing a "Lucid Dreaming Day."
Some people are so good at lucid dreaming, they can indicate to researchers, while they are asleep, that they’ve achieved lucidity. In a method developed in the 1970's by British Psychologist Keith Hearne and in the 1980’s by Stephen LaBerge—a psychophysiologist who did decades of dream research at Stanford and is considered the Godfather of lucid dream research by his fans—sleeping subjects are instructed to sweep their gaze from left to right within their dream twice when they’ve become lucid. Because eye muscles are not paralyzed during REM sleep (unlike the rest of the body’s muscles, which presumably prevents us from physically acting out our dreams, wandering out of the cave and getting eaten by a bear), sweeping your eyes from left to right in dreamland corresponds to doing so in real life.
Researchers can then pinpoint when a dreamer becomes lucid and more accurately track how neurological, respiratory, cardiovascular, and other physiological functions are acting during a lucid dream.
According to LaBerge, his EEG studies from the 1980’s showed that overall, the brain becomes more active at the onset of a lucid dream. His team also observed a physical autonomic reaction—sweating, increased respiration, and heart rate—and a spurt of increased eye movement during the transition into lucidity.
“It makes sense because becoming lucid is a surprise—so your body and brain reacts accordingly,” he said.
More recent studies also seek to discern how the brain acts during a lucid dream. Sergio Mota-Rolim, a researcher at The Federal University of Rio Grande de Norte in Brazil, has recently observed increased alpha brain waves (the waves associated with being awake with closed eyes) in lucid dreamers during REM sleep and conceptualizes lucid dreaming as a type of “micro-awakening” or sub-phase, of REM. In a 2009 study at the University of Frankfurt, Ursula Voss and her team observed an increase in gamma waves and coherence—a rough measurement of coordinated activity in the brain—during lucid dreams. So though researchers suspect something unique is happening in the brain during a lucid dream, the exact process is still unclear.