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Scientists finally know why sleep deprivation leads to mental sluggishness
Scientists didn’t know why the sleep deprived experienced cognitive lapses, until now.
Few things are worse for your health than long-term sleep deprivation. The sleep deprived have a higher risk of quite a number of conditions including heart disease, hypertension, type 2 diabetes, obesity, and depression. Lack of sleep also has a deleterious effect on the brain, particularly on memory and cognition.
Besides harried work schedules and our obsessions with our smart phones, sleep disorders are prevalent, with 50-70 million American adults experiencing one. Sleep apnea and insomnia are two of the most common examples. The issue has gotten so serious that the CDC has dubbed insufficient sleep a public health problem. 1 in 3 adults don't get enough sleep, a CDC report last year found.
On a societal level, sleep deprivation accounts for lost productivity, medical errors, and car and industrial accidents. One study showed that medical students doing their residency, which sometimes includes as long as 30-hour shifts, are more prone to mistakes. What scientists didn't know was why the sleep deprived suffered cognitive lapses, like forgetfulness or slower response time. That is until now.
1 in 3 US adults don't get enough sleep, which affects their health and cognition. Credit: Getty Images.
Dr. Itzhak Fried is a neurosurgeon at UCLA and Tel Aviv University. Along with colleagues, he recently discovered the neural underpinnings of sleep deprivation. The team also showed how such deficiencies lead to cognitive lapses. The authors describe their findings in a new paper published in the journal Nature Medicine. Dr. Fried and his team found that neurons literally can't function properly when we lack sleep. “This leads to cognitive lapses in how we perceive and react to the world around us," he said.
The study began with 12 patients who all suffer intractable epilepsy. Each patient was undergoing depth electrode monitoring. This is where a small hole is drilled into the skull and an electrode is placed inside. This is to determine where the seizures are emanating from, with the hope of correcting the issue through surgery.
Sleep deprivation can trigger a seizure. To shorten their stay in the hospital, the patients stayed up all night to evoke one. Researchers asked them several times over the course of the night to identify a number of images as fast as they could. These were six images of celebrities, famous landmarks, and animals. The implanted electrodes meanwhile recorded the combined firing of 1,500 neurons, which includes the brain activity of all 12 volunteers. Specific attention was given to the temporal lobe, responsible for memory and processing sensory information, including visual perception.
This exercise was performed on 24 separate occasions. As the night wore on and patients got drowsier, their ability to name the pictures quickly slowed, as did their neural activity. The neurons fired weakly and transmissions to other parts of the brain moved more slowly. As a result, participant response-time lagged.
Sleep deprivation literally slows down your brain activity. Credit: Getty Images.
“Slow, sleep-like waves disrupted the patients' brain activity and performance of tasks," Fried said in a press release. “This phenomenon suggests that select regions of the patients' brains were dozing, causing mental lapses, while the rest of the brain was awake and running as usual." Fried likened sleep deprivation to being drunk. “Yet no legal or medical standards exist for identifying overtired drivers on the road the same way we target drunk drivers," he said.
When the brain is sleep deprived, information isn't encoded by neurons as it should be, which is why our reaction time is slowed. It's like when a sleepy driver misses the fact that a person has stepped into the road. “The very act of seeing the pedestrian slows down in the driver's overtired brain," Fried said. “It takes longer for his brain to register what he's perceiving." The next phase is to come to understand the mechanism completely. For instance, why do neurons slow down due to sleep deprivation and why is their firing weaker?
To learn more about this experiment, click here:
What is human dignity? Here's a primer, told through 200 years of great essays, lectures, and novels.
- Human dignity means that each of our lives have an unimpeachable value simply because we are human, and therefore we are deserving of a baseline level of respect.
- That baseline requires more than the absence of violence, discrimination, and authoritarianism. It means giving individuals the freedom to pursue their own happiness and purpose.
- We look at incredible writings from the last 200 years that illustrate the push for human dignity in regards to slavery, equality, communism, free speech and education.
The inherent worth of all human beings<p>Human dignity is the inherent worth of each individual human being. Recognizing human dignity means respecting human beings' special value—value that sets us apart from other animals; value that is intrinsic and cannot be lost.</p> <p>Liberalism—the broad political philosophy that organizes society around liberty, justice, and equality—is rooted in the idea of human dignity. Liberalism assumes each of our lives, plans, and preferences have some unimpeachable value, not because of any objective evaluation or contribution to a greater good, but simply because they belong to a human being. We are human, and therefore deserving of a baseline level of respect. </p> <p>Because so many of us take human dignity for granted—just a fact of our humanness—it's usually only when someone's dignity is ignored or violated that we feel compelled to talk about it. </p> <p>But human dignity means more than the absence of violence, discrimination, and authoritarianism. It means giving individuals the freedom to pursue their own happiness and purpose—a freedom that can be hampered by restrictive social institutions or the tyranny of the majority. The liberal ideal of the good society is not just peaceful but also pluralistic: It is a society in which we respect others' right to think and live differently than we do.</p>
From the 19th century to today<p>With <a href="https://books.google.com/ngrams/graph?year_start=1800&year_end=2019&content=human+dignity&corpus=26&smoothing=3&direct_url=t1%3B%2Chuman%20dignity%3B%2Cc0" target="_blank" rel="noopener noreferrer">Google Books Ngram Viewer</a>, we can chart mentions of human dignity from 1800-2019.</p><img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDg0ODU0My9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTY1MTUwMzE4MX0.bu0D_0uQuyNLyJjfRESNhu7twkJ5nxu8pQtfa1w3hZs/img.png?width=980" id="7ef38" class="rm-shortcode" data-rm-shortcode-id="9974c7bef3812fcb36858f325889e3c6" data-rm-shortcode-name="rebelmouse-image" />
American novelist, writer, playwright, poet, essayist and civil rights activist James Baldwin at his home in Saint-Paul-de-Vence, southern France, on November 6, 1979.
Credit: Ralph Gatti/AFP via Getty Images
The future of dignity<p>Around the world, people are still working toward the full and equal recognition of human dignity. Every year, new speeches and writings help us understand what dignity is—not only what it looks like when dignity is violated but also what it looks like when dignity is honored. In his posthumous essay, Congressman Lewis wrote, "When historians pick up their pens to write the story of the 21st century, let them say that it was your generation who laid down the heavy burdens of hate at last and that peace finally triumphed over violence, aggression and war."</p> <p>The more we talk about human dignity, the better we understand it. And the sooner we can make progress toward a shared vision of peace, freedom, and mutual respect for all. </p>
Scientists find that bursts of gamma rays may exceed the speed of light and cause time-reversibility.
- Astrophysicists propose that gamma-ray bursts may exceed the speed of light.
- The superluminal jets may also be responsible for time-reversibility.
- The finding doesn't go against Einstein's theory because this effect happens in the jet medium not a vacuum.
Jet bursting out of a blazar. Black-hole-powered galaxies called blazars are the most common sources detected by NASA's Fermi Gamma-ray Space Telescope.
Cosmic death beams: Understanding gamma ray bursts<div class="rm-shortcode" data-media_id="cu2knVEk" data-player_id="FvQKszTI" data-rm-shortcode-id="c6cfd20fdf31c82cb206ade8ce21ba3f"> <div id="botr_cu2knVEk_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/cu2knVEk-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/cu2knVEk-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/cu2knVEk-FvQKszTI.js"></script> </div>
Researchers dramatically improve the accuracy of a number that connects fundamental forces.
- A team of physicists carried out experiments to determine the precise value of the fine-structure constant.
- This pure number describes the strength of the electromagnetic forces between elementary particles.
- The scientists improved the accuracy of this measurement by 2.5 times.
The process for measuring the fine-structure constant involved a beam of light from a laser that caused an atom to recoil. The red and blue colors indicate the light wave's peaks and troughs, respectively.
Scientists at Washington University are patenting a new electrolyzer designed for frigid Martian water.
- Mars explorers will need more oxygen and hydrogen than they can carry to the Red Planet.
- Martian water may be able to provide these elements, but it is extremely salty water.
- The new method can pull oxygen and hydrogen for breathing and fuel from Martian brine.