lowleveljetstream - Filed under 'science'

The Macbeth Effect

I just read a great article by NPR on the Macbeth Effect. 'Stressful
Decision? Washing Hands Could Help Soothe'

Here is the link: http://fluentnews.com/s/24309296

Filed under // research science

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Milano, Italy

Children of Bigger Gut

This is the second post on the effect of sleep deprivation on children and focuses on obesity.

This is really the story of one scientist who just didn't believe what was apparently gospel about children getting fat because of sedentary behavior - especially related to television viewing.

Dr. Elizabeth Vandewater at the University of Texas at Austin took on the challenge to prove that lack of exercise was not the cause of obesity. First, she found that obese children watch no more television than kids who aren't obese. Then she found that children only watch seven minutes more TV today than they did in the 1970's and while video games and internet surfing take up an additional 30 minutes on average on top of TV viewing, obesity appeared in the 1980's well before video gaming and internet usage occupied children's lives. She concluded that there was another cause.

Her proof of lazy science led to an effort to find the cause and it was Dr. Eve Van Cauter who discovered a 'neuroendocrine cascade,' which links sleep to obesity. "Sleep loss increases the hormone ghrelin, which signals hunger, and decreases its metabolic opposite, leptin, which suppresses appetite. Sleep loss also elevates the stress hormone cortisol. Cortisol is lipogenic, meaning it stimulates your body to make fat. Human growth hormone is also disrupted. Normally secreted as a single big pulse at the beginning of sleep, growth hormone is essential for the breakdown of fat."

In light of this discovery, sleep scientists have performed a number of analyses on large datasets of children. All the studies point in the same direction: on average, children who sleep less are fatter than children who sleep more. This inspired other countries to engage in the debate and studies in Japan (first graders), Canada (Kindergarten boys) and Australia (young boys) have concluded that children who get less than 8 hours sleep have a 300% higher rate of obesity than those who get a full ten hours of sleep. Research in Houston among middle schoolers and high schoolers showed that the odds of obesity went up 80% for each hour of lost sleep.

Van Cauter went on to discover that the stage of 'slow-wave sleep' is especially critical to proper insulin sensitivity and glucose tolerance. I will not go in to more detail on this other than to say that children spend over 40% of their sleep time in the 'slow-wave sleep' state, much more than adults and perhaps this an explanation for why obesity is much stronger in children than in adults.

So ironically what Vandewater and Cauter have discovered is that contrary to what was believed about exercise being a key driver against obesity. In fact children should spend more time doing the most sedentary inactivity possible - sleep.

This proves to me that those who challenge current belief systems are the ones who can change our future. It's disruptive and at times annoying but thank goodness for their challenging nature. Here's to the disbelievers.

Studies sourced: Vandewater, Elizabeth, "Media Use and Children's Health," Paper presented at the Population Association Annual Meeting, NYC.

Van Canter, Eve, Kristen Knutson, Rachel Leproult, and Karine Spiegel, "The Impact of Sleep Deprivation on Hormones and Metabolism," Medscape Neurology & Neurosurgery, Vol. 7

Filed under // Psychology Thought leadership health science

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Children of a Lesser Brain

I've just been reading some interesting studies on sleep deprivation in relation to children and the findings are astounding.

This is one of two posts. The first focuses on the brain and the second, on obesity.

Children - from elementary school through high school - are on average getting 1 hour less sleep today than they did 30 years ago and it's having its toll on their ability to do well in school but also potentially has much to do with the terrible teen syndrome.

Let's start by looking at the effect on children's ability. Dr. Avi Sadeh at Tel Aviv University did a test with 4th graders and 6th graders and found that by depriving the 6th graders of 1 hour's sleep per night for three nights, their performance level descended to a level of a normal 4th grader. In other words, a loss of one hour of sleep is equivalent to the loss of two years of cognitive maturation and development.

With the use of fMRI, Sadeh's findings can be further substantiated. Dr. Matthew Walker at UC Berkeley explains the neurobiological functioning based on sleep deprivation.

"Tired children can't remember what they just learned because neurons lose their plasticity, becoming incapable of forming new synaptic connections necessary to encode a memory." He goes on to explain "During sleep, the brain shifts what it learned that day to more efficient storage regions of the brain. Each stage of sleep plays it own unique role in capturing memories. For example studying a foreign language requires learning vocabulary, auditory memory of new sounds, and motor skills to correctly enunciate the new word. The vocabulary is synthesized by the hippocampus early in the night during 'slow-wave sleep,' a deep slumber without dreams. The motor skills of enunciation are processed during stage 2 non-REM sleep, and the auditory memories are encoded across all stages. Memories that are emotionally laden get processed during REM sleep. The more you learned during the day, the more you need to sleep that night.

"To reconsolidate these memories, certain genes appear to upregulate during sleep - they literally turn on, or get activated. One of these genes is essential for synaptic plasticity, the strengthening of neural connections. The brain does synthesize some memories during the day, but they're enhanced and concretized during the night - new inferences and associations are drawn, leading to insights the next day."

Being loose on the discipline around sleep is like being loose on the discipline around drugs and alcohol. All three are harmful. Not forcing your children to get enough sleep is equivalent to depriving them of learning. This will be a significant hurdle for them in their future growth and opportunities. According to a study from Rhode Island, 94% of high schoolers set their own bedtimes. Maybe this is not such a good idea.

Looking in to brain functioning further reveals another interesting fact. Have you found that when you lack sleep, you start to go in to a more negative space in your head? You start doubting and start getting in to a bad insecure space? OK, this might just be me but at least thanks to Dr. Walker I understand what's happening. Emotional context of a memory affects where it gets processed. Negative stimuli gets processed by the amygdala; positive or neutral memories gets processed by the hippocampus. Sleep deprivation hits the hippocampus harder than the amygdala. The result is that sleep-deprived people fail to recall pleasant memories, yet recall gloomy memories just fine.

In Dr. Walker's tests, he found that sleep deprived kids could remember 81% of the words with a negative connotation, like cancer. But they could remember only 31% of the words with a positive or neutral connotation like 'sunshine' or 'basket'.

What does this all mean? Kids apparently are over extended, which is depriving them of sleep. While they may touch more subjects, play more sports and experiment with more extra-curricula activities, their brains are not computing and therefore their cognitive abilities are not able to keep up. We are producing children of a lesser brain.

Oh and don't forget that second tidbit about negativity. While not proven as yet, there's a strong belief that sleep deprivation is causing children's moodiness, depression, and even binge eating. Forcing them to get more sleep may make for a more pleasant household.

Studies sourced: Avi Sadeh, Reut Gruber, and Amiram Raviv, "The Effects of sleep Restriction and Extension on School-Age Children: What a Difference an Hour Makes" Child Development, Vol. 74.

Walker, Matthew P., and Robert Stickgold, "Sleep-Dependant Learning and Memory Consolidation." Neuron, Vol. 44

Walker, Matthew P., and Robert Stickgold, "Sleep, Memory & Plasticity," Annual Review of Psychology, Vol. 57.

Filed under // Psychology Thought leadership health science

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Shot Down

There's some noise on the web about the laser guided mosquito killer that was showed at TED last week.

I find the story behind its invention, by Intellectual Ventures Lab, even more compelling.

Nathan Myhrvold, formerly of Microsoft, created the mosquito killer from parts he bought on Ebay. He used parts from printers, digital cameras and projectors to create a new device that could eventually change the course of Malaria forever.

Even with such basic ingredients, the device can precisely identify a female mosquito from other mosquitoes or other insects. It will only kill the females as they are the ones that bite. Why save the males? Simply because there's no point wasting energy on them. It can kill 50 to 100 mosquitoes a second.

There's that Gutter Technology at play again.

Disappointing Surprises

via wired.co.uk

I found this interesting article in the UK Wired magazine on Kevin Dunbar, a researcher who studies how scientists study things.

The key points are captured below:

"[Kevin] Dunbar came away from his year of living 24/7 with scientists and four years analyzing the data with an unsettling insight: science is a deeply frustrating pursuit. Although the researchers were mostly using established techniques, more than 50 percent of their data was unexpected."

"The scientific process...is supposed to be an orderly pursuit of the truth, full of elegant hypotheses and control variables. However, when experiments were observed up close this idealized version of the lab fell apart, replaced by an endless supply of disappointing surprises".

"So how did they deal with so much failure? Dunbar realized the vast majority of people in the lab followed the same basic strategy. First, they would blame the method. The surprising finding was classified as a mere mistake; perhaps a machine malfunctioned or an enzyme had gone stale. "The scientists were trying to explain away what they didn't understand," Dunbar says. "It's as if they didn't want to believe it."

I love how the end state of blame and disbelief exists even in the most rational work environments. How often do we blame before we work out what went wrong?

Check out the article here http://bit.ly/6PqQec but...

...the real reason for this post is to ignite conversation and thought around John Winsor's project on failure.

Check out his post below
http://www.johnwinsor.com/my_weblog/2010/01/lets-talk-about-the-other-f-word....

Filed under // Thought leadership failure science

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The Macbeth Effect

Children of Bigger Gut

Children of a Lesser Brain

Shot Down

Disappointing Surprises