Earlier this year, a puzzling report appeared in the journal Sleep Medicine. It described two Italian people who never truly slept. They might lie down and close their eyes, but read-outs of brain activity showed none of the normal patterns associated with sleep. Their behaviour was pretty odd, too. Though largely unaware of their surroundings during these rest periods, they would walk around, yell, tremble violently and their hearts would race. The remainder of the time they were conscious and aware but prone to powerful, dream-like hallucinations.
Both had been diagnosed with a neurodegenerative disorder called multiple system atrophy. According to the report’s authors, Roberto Vetrugno and colleagues from the University of Bologna, Italy, the disease had damaged the pair’s brains to such an extent that they had entered status dissociatus, a kind of twilight zone in which the boundaries between sleep and wakefulness completely break down (Sleep Medicine, vol 10, p 247).
An article about the breakdown between sleep and wakefulness, tying together a bunch of different phenomena, like morning grogginess, insomnia, sleep paralysis, sleepwalking, night terrors, “microsleep”, sleep deprivation and “mosaic sleep”, in which some parts of the brain fall asleep while the rest is awake — “It is like having a temporary mental disorder without anyone, including yourself, being aware of it.” Interesting stuff.
I think one of the most interesting findings regarding literacy and the human cortex is the fact that there are actually two distinct pathways activated by the sight of letters. (The brain is stuffed full of redundancies.) As the lab of Stanislas Dehaene has found, when people are reading “routinized, familiar passages” a part of the brain known as the visual word form area (VWFA, or the ventral pathway) is activated. This pathway processes letters and words in parallel, allowing us to read quickly and effortlessly. It’s the pathway that literate readers almost always rely upon.
But Dehaene and colleagues have also found a second reading pathway in the brain, which is activated when we’re reading prose that is “unfamiliar”. (The scientists trigger this effect in a variety of ways, such as rotating the letters, or using a hard to read font, or filling the prose with obscure words.) As expected, when the words were more degraded or unusual, subjects took longer to comprehend them. By studying this process in an fMRI machine, Dehaene could see why: reading text that was highly degraded or presented in an unusual fashion meant that we relied on a completely different neural route, known as the dorsal reading pathway. Although scientists had previously assumed that the dorsal route ceased to be active once we learned how to read, Deheane’s research demonstrates that even literate adults still rely, in some situations, on the same patterns of brain activity as a first-grader, carefully sounding out the syllables.
Did you slow down as you read the above? I know I did the moment I became conscious of the fact that I’m supposed to be able to read it effortlessly. (found here)
Europa has more liquid water than the Earth. What has made the chances of finding life there seem small is that its sea lies under miles of ice. But now, scientists think enough oxygen reaches the sea to support not only bacteria but macroscopic life. (I say: forget manned missions to the Moon or Mars, let’s go to Europa!)
Given the amount of media fuss about the cervical cancer vaccine recently, particularly in the UK, this is very timely. And quite beautifully presented.
The most striking point is the difference between the odds of dying after the vaccine (15,200,000:1) and dying in a road accident the year after the vaccine (a mere 10,000:1).
Striking because the newspaper inches given to each of these causes of death is pretty much the reverse…
This math may not have many scientific applications, but it’s simply beautiful: CellarAcademic explains infinite set theory in simple terms (parts one and two). Also, I took a stab at explaining some of this a while back. (via Tristan)
Since man first touched the moon and brought pieces of it back to Earth, scientists have thought that the lunar surface was bone dry. But new observations from three different spacecraft have put this notion to rest with what has been called “unambiguous evidence” of water across the surface of the moon.
The moon remains drier than any desert on Earth, but the water is said to exist on the moon in very small quantities. One ton of the top layer of the lunar surface would hold about 32 ounces of water, researchers said.
On September 2, 1859, the Earth witnessed the perfect solar storm. If anything on the same scale happened today, “the damage could range upwards of a $1 trillion, largely because of disruptions to the electrical grid.”
