(Image: bzztbomb)
Researchers at the University of Minnesota’s Center for Magnetic Resonance Research (CMRR) have found a small population of neurons that is involved in measuring time, which is a process that has traditionally been difficult to study in the lab.
In the study, which is published October 30 in the open access journal PLOS Biology, the researchers developed a task in which monkeys could only rely on their internal sense of the passage of time. Their task design eliminated all external cues which could have served as “clocks”.
The monkeys were trained to move their eyes consistently at regular time intervals without any external cues or immediate expectation of reward. Researchers found that despite the lack of sensory information, the monkeys were remarkably precise and consistent in their timed behaviors. This consistency could be explained by activity in a specific region of the brain called the lateral intraparietal area (LIP). Interestingly, the researchers found that LIP activity during their task was different from activity in previous studies that had failed to eliminate external cues or expectation of reward.
“In contrast to previous studies that observed a build-up of activity associated with the passage of time, we found that LIP activity decreased at a constant rate between timed movements,” said lead researcher Geoffrey Ghose, Ph.D., associate professor of neuroscience at the University of Minnesota. “Importantly, the animals’ timing varied after these neurons were more, or less, active. It’s as if the activity of these neurons was serving as an internal hourglass.”
By developing a model to help explain the differences in timing signals they see relative to previous studies, their study also suggests that there is no “central clock” in the brain that is relied upon for all tasks involving timing. Instead, it appears as though each of the brain’s circuits responsible for different actions are capable of independently producing an accurate timing signal.
One important direction for future research is to explore how such precise timing signals arise as a consequence of practice and learning, and whether, when the signals are altered, there are clear effects on behavior.
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neuroticthought reblogged neurosciencestuffSource: medicalxpress.comHow does the brain measure time? -
Have you ever heard of the amazing and inspirational Carl Sagan?
Carl Sagan was an American astronomer, astrophysicist, cosmologist, author and science communicator. Why inspirational? Well, there are many intelligent beings in the world but not all of them are capable of communicating and appealing to the people like Carl Sagan did. Carl Sagan did this through his books and various media (The Cosmos being especially popular).
Why bring him up now?
Well, today, along with many other humans, Carl Sagan was born 78 years ago on November 9th 1934. So happy Carl Sagan Day!
“For small creatures such as we the vastness is bearable only through love.” - Carl Sagan.
“If you wish to make an apple pie from scratch, you must first invent the Universe”. - Carl Sagan.
I recommend all of you to listen to this video by Symphony of Science “A glorious dawn ft. Stephen Hawking”: http://www.youtube.com/watch?v=zSgiXGELjbc
Picture source:
http://blogs.agu.org/wildwildscience/2010/12/20/carl-sagan-passed-14-years-ago-today-his-legacy-endures/
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Yesterday we did a historic thing. We generated 87,834 phone calls to U.S. Representatives in a concerted effort to protect the Internet. Extraordinary. There’s no doubt that we’ve been heard.
So just to keep you updated: The well-intentioned, but immensely flawed “Stop Online Piracy Act” is still in the House Judiciary Committee. The hearing was yesterday and now members will debate and bring amendments to the bill. The Committee will reconvene in a few weeks — the date has yet to be scheduled. Nothing has been brought to a final vote. Everything is still very much in play. We’ll keep you posted on what’s going on and what you can do to help. But for now, we want to thank you.
One encouraging thing we heard yesterday:
I don’t believe this bill has any chance on the House floor. I think it’s way too extreme, it infringes on too many areas that our leadership will know is simply too dangerous to do in its current form.
— Representative Darrell Issa
We also want to express our tremendous gratitude to our friends at Mobile Commons who, on 30 minutes notice, hooked us up with their amazing platform (and provided their expertise) to automatically connect callers with their Representatives.
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Skysurvey.org is the largest ever true color all-sky photograph. 5 kilopixel panorama of 37,440 exposures from 2 hemispheres. This is what you’d see if the Earth suddenly became transparent and the sky were 3000 times brighter. I love how strongly you can perceive the disc of the Milky Way; we’re at the outer edge so there’s a lot of stars between us and the core.
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“Sam Harris on the ‘selfish gene’ and moral behavior
“Many people imagine that the theory of evolution entails selfishness as a biological imperative. This popular misconception has been very harmful to the reputation of science. In truth, human cooperation and its attendant moral emotions are fully compatible with biological evolution. Selection pressure at the level of ‘selfish’ genes would surely incline creatures like ourselves to make sacrifices for our relatives, for the simple reason that one’s relatives can be counted on to share one’s genes: while this truth might not be obvious through introspection, your brother’s or sister’s reproductive success is, in part, your own. This phenomenon, known as kin selection, was not given a formal analysis until the 1960s in the work of William Hamilton, but it was at least implicit in the understanding of earlier biologists. Legend has it that J.B.S. Haldane was once asked if he would risk his life to save a drowning brother, to which he quipped, ‘No, but I would save two brothers or eight cousins.’
The work of evolutionary biologist Robert Trivers on reciprocal altruism has gone a long way toward explaining cooperation among unrelated friends and strangers. Trivers’s model incorporates many of the psychological and social factors related to altruism and reciprocity, including friendship, moralistic aggression (i.e., the punishment of cheaters), guilt, sympathy, and gratitude, along with a tendency to deceive others by mimicking these states. As first suggested by Darwin, and recently elaborated by the psychologist Geoffrey Miller, sexual selection may have further encouraged the development of moral behavior. Because moral virtue is attractive to both sexes, it might function as a kind of peacock’s tail: costly to produce and maintain, but beneficial to one’s genes in the end.
Clearly, our selfish and selfless interests do not always conflict. In fact, the well-being of others, especially those closest to us, is one of our primary (and, indeed, most selfish) interests. While much remains to be understood about the biology of our moral impulses, kin selection, reciprocal altruism, and sexual selection explain how we have evolved to be, not merely atomized selves in thrall to our self-interest, but social selves disposed to serve a common interest with others.” ”— Sam Harris, American author, and CEO of Project Reason. He received a Ph.D. in neuroscience from UCLA, and is a graduate in philosophy from Stanford University, The Moral Landscape, Free Press, 2010. -
Source: funguerilla.com
Scientific photographer Steve Gschmeissner, 61, from Bedford, uses a Scanning Electron Microscope (SEM) to magnify his favourite specimens by up to a million times. The results show incredibly detailed images of creepy crawlies in 3D.
The SEM is far more powerful than regular light microscopes that can only magnify by up to 1000 times. It builds extreme close-ups of anything that can fit inside the 4ft high device by bombarding it with electrons. The electrons send back messages which help to build up a super-accurate image – revealing every tiny feature of the insects’ bodies down to the last hair – in spectacular fashion.
