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Let's lead with last month's autism news: the UW Daily reports that "an international autism study group, with the help of UW scientists, found a gene linked to a child’s chance of having autism." But before you get too worked up, they also mention that: "Scientists believe there may be anywhere from five to 15 major genes that must come together to contribute to autism, as well as an additional 30 - 40 minor genes."
The excitement around the neurexin 1 gene is not due to hopes of a cure: the goal at this point is to find a way to tell early on which child may have a significant chance of developing autism, so that they can receive intervention as early as six to twelve months of age, during critical developmental periods. At this point, it can be difficult to spot autism until delayed developmental effects are visible.
We learned two things at the final lecture in the 2007 Edwards Psychology Lecture Series at the UW, which we'll get to in a second. First, did you know that the UW psychology department receives $100,000 in research money annually? (So $15,000 probably does count as real money.)
Scott Murray's latest research on vision and the brain proves that Missouri's state slogan smacks more of egocentric paranoia than a fondness for reliable truth. It turns out that even very early in the vision process -- in the cortical retinotopic mapping previously believed to be simply the "results" of light striking the retina -- your brain is interpreting the data. In Murray's experiments with object size, he's shown that the earliest visual map your brain creates already incorporates perceptual effects (notably, depth perception that creates senses of relative size).
Seeing may be believing, but only because we have no choice in what we see. Visual reality is not a more or less one-to-one relationship with the external world, but a tool to help us move around, act appropriately for survival, in most instances. That was the thread taken up by visiting professor Melvyn Goodale, from the University of Western Ontario.
Despite being an outspoken Canadian chauvinist (claiming to have a larger Tesla magnet than ours!), Goodale was somehow allowed entry to the U.S. -- we can only hope he was kept under close surveillance. His research has involved distinguishing between two separate visual systems that we think are the same one: the ventral (occipital to temporal lobe) and dorsal (occipital to parietal lobe) visual streams.
The ventral stream is what we "see," a detailed picture, full of edges, color, and shading. But the older dorsal stream is, Goodale believes, the foundation of vision. He says that vision evolved as a system for the control of distal action and movement (pointing to the euglena alga, an early sun worshiper which reacts to light and dark with flagellar activity). For us, the dorsal stream allows us to form and hold in mind motor coordinates for the space around us -- more accurate and less prone to visual illusion than the ventral stream.
Thanks to research on patients who have damage to either the ventral or dorsal stream, Goodale has been able to determine that these areas function mostly independently of each other, though we imagine that what we see is wholly what we're reacting to. Yet most of our movements are based on a kind of vision we're unconscious of (we do have the option of relying on perceptual memory with our eyes closed, but most of us aren't very good at it).
As an example of conscious/unconscious vision, Goodale pointed out that object constancy is the basis of our perception: no matter how different an object looks from above, behind, below, from right or left, from far or near, we see it as a single object. But to interact with any object, to pick it up, walk around it, or kick it, we need to see it exactly as its located in space, from a singular orientation (people with damage to their dorsal stream don't "pre-set" their hand's grasp when reaching for a larger or smaller object).
It is our opinion that this discrepancy in viewpoint is somehow related to those times we've accidentally slapped a pint of beer off the table because it wasn't where it looked like it was. Now we'll have science to fall back on for future defense.
Image from Mighty Optical Illusions.
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Too much in house banter. For those not asosciated with whatever researchfacility/personal fued, you are experiencing with different scientists, it is very distracting to filter them out of what should be an informatory article. Place your character disagreements in loftier terms. Even sciens editorials should have rules.
Gretchen, I'm guessing you found this post via a search engine. Just so you know, this is a city blog, not a science editorial. (This post follows a post about kitchen faucet replacement.) And Goodale's remarks about Canadian-U.S. rivalry were completely facetious and charming.