What you see is not what is out there in the world – not exactly, at least. Scientists have shown that your brain is tweaking the light coming in from your eyes and making predictions about what you expect to see. The “blind spot” experiment is well known to students. That’s where it can be shown that your brain “fills in” the blind spot of each eyeball (where the optic nerve leaves the retina, with no photoreceptors) with imagery from the surrounding field. A brick wall pattern, for instance, continues seamlessly into the blind spot even though your eye actually receives no light from that part of the retina. Researchers at the University of Glasgow performed four experiments on participants, and monitored brain activity with functional MRI, to see what parts of the visual field were doing when shielded from visual input. Their findings were published in PNAS.1 It appears that the context influences what we “see.” The primary visual cortex (V1) uses context and memory to prepare the image presented to the mind.We used functional magnetic resonance imaging (fMRI) and pattern-classification methods to show that the cortical representation of a nonstimulated quarter-field carries information that can discriminate the surrounding visual context. We show further that the activity patterns in these regions are significantly related to those observed with feed-forward stimulation and that these effects are driven primarily by V1.The way PhysOrg put it, “What our eyes can’t see, the brain fills in.” And it fills it in from prior experience: “The results show that our brains do not rely solely on what is shown to the eyes in order to ‘see’. Instead the brain constructs a complex prediction” of what it expects to see.” One neuroscientist called this “predictive coding.” Dr. Lars Muckli from U of Glasgow explained how this is helpful: “If you are driving a car and a pedestrian is suddenly obscured – say by a pillar box or your rear view mirror – your brain still knows where they are and where they will reappear in your line of vision. Without that ability, we would be lost in everyday life.” For more on image processing done by the eye and brain, see 05/22/2003, 12/30/2003, 05/12/2005, 07/27/2006 and 03/31/2008.1. Smith and Muckli, “Nonstimulated early visual areas carry information about surrounding context,” Proceedings of the National Academy of Sciences USA, published online before print November 1, 2010, doi: 10.1073/pnas.1000233107 (open access). Note: the paper was published Nov 1, 2010, but PhysOrg reported on it April 4, 2011.Unfortunately, Dr. Muckli tossed in this Darwin stinkincense bomb: “The brain’s main function is to minimise surprise – that is what it has evolved to do.” Were you surprised? That not only violates logic, it violates Darwin’s own principle of Stuff Happens. Things don’t evolve to do anything in Darwinland; they just evolve. Implying a purpose for anything invokes teleology – something Darwin and his disciples wanted to eliminate. Enough of that distraction. Findings like these bear on important philosophical questions about the relationship of our senses to external reality. Philosophers have long wondered to what extent we can trust our senses. There is a long chain of causal phenomena interceding between the photons emitted by an object and our perception of that object by the mind. Here we see that our brains are manipulating reality for us in ways that can be tricked by experience or novelty. Those who say they only believe what they can see should realize they cannot see the whole electromagnetic spectrum, for one thing, and the narrow range of visible light they can see is being transformed by their brains. The only worldview that provides grounds for trusting our senses comes from the Bible. Our eyes and brains were created by a Creator who loves honesty and truth, and has equipped his creatures with sufficient equipment to have reasonable, though not exhaustive, access to external reality. Otherwise we would be “lost in everyday life” and unable to respond to him by perceiving his works. Even so, we need to train our equipment to discern the truth, and not deceive ourselves.(Visited 42 times, 1 visits today)FacebookTwitterPinterestSave分享0
marshall kirkpatrick Why Tech Companies Need Simpler Terms of Servic… A Web Developer’s New Best Friend is the AI Wai… Today is global Data Privacy Day and companies all around the world are marking it in different ways. Below we’ve highlighted some of the activities of Microsoft, Google, Facebook, Opera and IBM.Those actions range from implementing new technologies through making blog posts highlighting existing policies. Do you feel like these companies are responsive to your concerns about data privacy in 2011? Microsoft put up a blog post highlighting its strong security measures baked into Hotmail and Windows Live. That’s nice.European mobile mega-browser company Opera posted the results of an interesting survey it commissioned regarding digital privacy concerns around the world. One highlight:Worried about who is watching you online? Some 38% of Russian respondents were most concerned about social-networking websites having too much insight into their online behavior, far ahead of 15% in the United States and 10% in Japan, where social media ranked number 2. U.S. participants were most concerned about the government (35%). Japan held least trust in shopping sites (33%), while only 5% and 6% respectively in Russia and United States shared the same anxiety. Between 13 and 19% of respondents in each country were not worried about anyone gaining insight into their online activities.Facebook implemented HTTPS secure connections so that users don’t get hijacked by Firesheep and other such programs. The company also faced widespread criticism on privacy, again, now for this week’s move to allow advertisers to sponsor particular status updates from users.Google is hosting a public hearing in Washington DC called “The Technology of Privacy: When Geeks Meet Wonks.” A video of that hearing will be posted on the Google Privacy channel on YouTube. Alma Whitten, Google’s Director of Privacy, Product and Engineering, is clearly committed to balancing peoples’ privacy interests with the interests in innovation held by Google and its users.My favorite big company move is probably IBM’s running of a column on the topic on its Smarter Planet blog. Harriet Pearson, VP Security Counsel & Chief Privacy Officer at IBM, focuses on the Internet of Things and the importance of securing trust through privacy in order to build sustainable technology that can change the world.What’s at stake? Plenty. Getting data privacy “right” is an economic and social imperative. Trust and confidence in the security and privacy of the critical systems of our planet – especially the digital version of its central nervous system, the Internet – is foundational to individuals’ continued engagement and reliance on such things as online commerce, e-health and smart grids. If individual consumers don’t feel that their privacy and security are protected, they will not support modernization efforts, even though the capabilities of technology advancements are proven and the potential benefits to society are extensive.What’s at the forefront of your mind about digital privacy, here on this Digital Privacy Day?Disclosure: IBM is also a ReadWriteWeb sponsor. Top Reasons to Go With Managed WordPress Hosting 8 Best WordPress Hosting Solutions on the Market Related Posts Tags:#privacy#web
The Defence Ministry on Saturday denied reports of an Army jawan being abducted by militants from his home in central Kashmir’s Budgam district, saying he is “safe”.The family of Mohammad Yaseen, who is posted with the Jammu and Kashmir Light Infantry (JAKLI) Regiment, had on Friday informed the police that some people came to their house at Qazipora Chadoora in Budgam and took him away.Mr. Yaseen was on leave. However, a Defence spokesperson on Saturday said the reports of the abduction of the jawan were incorrect.“Clarification. Media reports of the abduction of a serving Army soldier on leave from Qazipora, Chadoora, Budgam are incorrect. Individual is safe. Speculations may please be avoided,” the spokesperson said in a tweet.An Army official said they are trying to ascertain where the jawan had been on Friday night which prompted his family to approach the police.