The room is dark, carpeted, and almost silent, except for one speaker in the corner about to play the sound of a jet taking off.<\/p>\n
A volunteer lies still under a tangle of wires taped to her scalp.<\/p>\n
She has slept here before, under conditions she did not choose.<\/p>\n
Tonight the trendy fix goes up against the cheapest thing<\/strong> in the drawer.<\/p>\n One is a staticky hush marketed to soothe restless sleepers everywhere, the other a foam plug nobody bothers to advertise.<\/p>\n So why did the cheap one win<\/strong>?<\/p>\n The pink noise<\/strong> used here is not random hiss. Like white noise it contains every frequency people can hear, but it plays the lower ones more prominently, which is why it gets compared to rain and ocean waves. The idea behind piping it into a bedroom is masking.<\/p>\n So a steady wash of sound should, in theory, bury sudden spikes, like a passing truck or a slammed door, so the sleeping brain never has to notice them. Earplugs attack the problem from the opposite end instead.<\/p>\n They do not try to out compete the noise with more noise. They cut it at the ear<\/strong>, letting the room return to something closer to true silence, while masking adds new information<\/strong> all night long.<\/p>\n That difference is the proposed explanation for what the measurements showed, not a settled mechanism. The authors themselves note that research on the effects of broadband noise on sleep remains scarce and inconclusive<\/strong>.<\/p>\n The headline result is that the two kinds of sound are fundamentally different. Intermittent environmental noise primarily shortened N3 deep sleep, while continuous pink noise shortened REM sleep instead. Those are not interchangeable losses, because deep sleep clusters early in the night and REM builds later, so a fix aimed at one can leave the other exposed.<\/p>\n Layering pink noise over aircraft noise made things worse than either alone. Both deep sleep and REM sleep were significantly shorter than on quiet control nights, and time awake rose<\/strong> by about 15 minutes, which had not happened on either noise condition by itself.<\/p>\n Participants also reported lighter sleep, more awakenings<\/strong> and worse overall quality under aircraft noise or pink noise, unless they used earplugs.<\/p>\n Researchers at a Pennsylvania medical school ran the trial and published it in a sleep journal. It was a randomized, controlled, crossover study in 25 healthy adults<\/strong> across seven laboratory nights, each one monitored with brainwave sensors through the night.<\/p>\n The nights compared a quiet control, realistic traffic noise events, pink noise at two volumes, the two combined, and environmental noise paired with earplugs. The group skewed toward younger women, and the environmental track ranged from traffic sounds to sonic booms, with nobody reporting a prior sleep disorder or routine use of sound machines.<\/p>\n Which is what makes the earplug numbers so striking. Aircraft noise, compared with none, was linked to about 23 fewer minutes per night in N3, the deepest stage, and earplugs recovered 16<\/strong>.9 of those 23.4 minutes, or roughly 72 percent, without touching REM sleep.<\/p>\n Pink noise told a different story. Alone at 50 decibels, roughly the sound of moderate rainfall, it was linked to a nearly 19 minute decrease<\/strong> in REM sleep. The standard earplugs used in the study provided an average attenuation of 25.5 decibels<\/strong>, a figure ordinary foam plugs can roughly match.<\/p>\n The paper<\/a> is blunt about the comparison. Earplugs emerged as clearly superior to constant pink noise for blunting the effects of intermittent environmental noise, the authors wrote.<\/p>\n The lead author, a psychiatry professor at the medical school, told reporters<\/a> he did not expect pink noise to disturb sleep to that degree, though it did help participants sleep through traffic sounds. The steady foam plug<\/strong> still beat it at blocking noise out entirely.<\/p>\n The researcher has not written sound machines off entirely. Pink noise eased some of the deep sleep reduction and fragmentation caused by intermittent environmental noise, and for people whose main problem is fragmented sleep, he said it could still help overall.<\/p>\n His sharper warning is about children, whose brains are still developing and who spend far more time<\/strong> in REM sleep than adults. The study itself did not test babies or children, and it was run in a lab bed none of the volunteers had slept in before.<\/p>\n Even so, the pattern is worth carrying home, built on the same kind of tightly controlled monitoring<\/a> used elsewhere to measure what bodies do under steady stress, the same discipline behind lab comparisons<\/a> of cheap household fixes against pricier alternatives.<\/p>\n The authors conclude that earplugs, used by as many as 16 percent of Americans<\/strong> to sleep, are likely effective, while the broader health effects of pink noise and other broadband sleep aids still need more thorough study. For now the humble foam plug<\/strong> is the option that held up where brainwaves, not guesswork, were doing the measuring.<\/p>\n","protected":false},"excerpt":{"rendered":" The room is dark, carpeted, and almost silent, except for one speaker in the corner about to play the sound of a jet taking off. A volunteer lies still under a tangle of wires taped to her scalp. She has slept here before, under conditions she did not choose. Tonight the trendy fix goes up … Read more<\/a><\/p>\n","protected":false},"author":28,"featured_media":45179,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"rank_math_focus_keyword":"volunteers slept 7","rank_math_title":"Volunteers slept 7 nights wired up in a sealed laboratory bedroom, and plain foam earplugs gave back more than 70 percent of the deep sleep that outside noise had taken","rank_math_description":"A sealed sleep lab trial found pink noise trimmed REM sleep overnight, while plain foam earplugs recovered most of the deep sleep that outside noise destr","footnotes":""},"categories":[25],"tags":[],"class_list":["post-45174","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-human-science"],"_links":{"self":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/45174","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/users\/28"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/comments?post=45174"}],"version-history":[{"count":1,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/45174\/revisions"}],"predecessor-version":[{"id":45180,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/posts\/45174\/revisions\/45180"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/media\/45179"}],"wp:attachment":[{"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/media?parent=45174"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/categories?post=45174"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ecoportal.net\/en\/wp-json\/wp\/v2\/tags?post=45174"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Masking a noisy night with more sound is not the same as removing it<\/h2>\n
Bursts of outside noise and a constant hum hit two different sleep stages<\/h2>\n
Twenty five adults spent seven nights wired up for the trial<\/h2>\n
More than 70 percent of the lost deep sleep came back with foam<\/h2>\n
What eight years of caveats still leave open about your own bedroom<\/h2>\n