neurodudes

Maurer, D., & Mondloch, C. Neonatal synesthesia: A re-evaluation. In L. Robertson & N. Sagiv (Eds.), Attention on Synesthesia: Cognition, Development and Neuroscience, Oxford University Press, 2004. Pp. 193-213.

This article postulates that babies experience synaesthesia.

I’m not convinced of that hypothesis because (although I only skimmed the article), I couldn’t find any evidence of something that infants and synaesthetes do that non-synaesthetes do not do. But it still reviews some interesting facts.

There are apparently a number of tasks that demonstrate, to quote the article, “paradoxical evidence of U-shaped development of cross-modal perception: Babies demonstrated successful linking of information across sensory modalities near birth, failed at similar tasks later in infancy, and then appeared to gradually learn cross-modal links in the second half of the first year of life.”

The article also reviews evidence for mysterious, presumably innate cross-modal correspondences in normal adults. For example, high frequency sounds go together with lighter colors. Angular shapes go with aggression, strongness, and loudness. Brighter light goes with loudness.

This Is Your Brain Under Hypnosis - New York Times

Very interesting stuff. Subjects were hypnotized and told that days later they would see “gibberish” symbols printed in particular colors. They needed to report back the color that the word appeared in. (For those unfamiliar, the Stroop test presents color words, like “red”, in a different color, such as the word “red” written with green ink. People have difficulty reporting the color of the word because we have a strong need to “read” the written word.)

The highly hypnotizable subjects (grouped according to a predetermined measure) essentially showed no Stroop effect (ie. no reaction time difference with conflicting word and color). And, with fMRI, they saw that normally activated visual-reading areas were not activated in these subjects.

His Holiness has spoken. He wants neuro-drugs to take and electrodes stuck in his brain so that he doesn’t have to spend hours meditating each day. (Enlightenment now!) If you want to do hot stuff, study physics or brain science. His interest in neuroscience stems from a long-standing interest in body hair. Yes, body hair. Americans need to figure their own way through this whole intelligent design business. Not all antidepressants are alike; for instance, the Dalai Lama is against tranquilizers. Definitely against tranquilizers. And, perhaps most surprisingly, His Holiness, approves of animal research — when it’s done right and with respect.

Minute-by-minute liveblog follows after the jump.
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Although Bayle and I are always surprised when we see how many people are actually reading Neurodudes every day (”you really like us! you really do!”), I think we realized we had hit a new milestone when Ray Kurzweil’s book agent called to give us an advance copy of his new book. Let me be clear here: We will gladly review any AI-/neuro-related books you send us. Free books are great! (Heck, we’ll even do an occasional historical biography, if you send us one.)

There’s a lot to say about Kurzweil’’s new book, The Singularity is Near (book website; book on Amazon). This book is similar to his previous books (Age of Intelligent Machines, Age of Spiritual Machines) in style and research but the thesis here is that we are on the precipice of a major change in human civilization: We are soon going to create entities of superior intelligence in all aspects to our own selves. This is the Singularity.

Full book review after the jump (more…)

A funny and insightful philosophy article by Jaron Lanier about consciousness and the possibility of “zombies”, i.e. humans who act like the rest of us but who aren’t conscious.

http://www.davidchess.com/words/poc/lanier_zombie.html

The way that general anesthetics work is still somewhat mysterious. Here’s one intriguing hypothesis.

Anesthetics increase conduction velocity in myelinated fibers. Perhaps they disrupt the carefully calibrated timing of axonal transmission. This may selectively interfere with spike timing-based computation, while leaving rate-based computation intact. If consciousness (or some general class of higher-order functions) is spike timing based, but lower-order functions are rate-based, this would explain why anesthetics selectively affect higher-order functions.

Swindale, Nicholas V. Neural Synchrony, Axonal Path Lengths, and General Anesthesia: A Hypothesis. Neuroscientist 2003 9: 440-445

I didn’t read the article yet (I don’t have access privs to that journal), but it looks cool.

(related NeuroWiki page: GeneralAnesthesia)

Jeremy Wolfe has written a review of Christof Koch’s new book on consciousness. This one seems directed more toward the casual reader.

Review is here.

Really elegant study in Nature Neuroscience showing how attention (consciousness for you philosophers…) can modulate perception. Most previous work that I’ve seen has been about how attention changes response time but this study shows how the percept itself can change.

The neat part is that the experimenters found a way of assaying stimulus salience (contrast, in this case) without directly asking. It’s interesting to see how this “Holy Grail of Consciousness” is being scientifically deconstructed bit-by-bit with rather simple experiments. Check out the full article here or click below for the news & views.
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