Supports my view of sense, Invalidates mechanistic assumptions about eyes.

The genie about the reality of sense just doesn't seem to want to stay in 
the bottle...


*Experiments with tadpoles show ectopic eyes that "see"* 
> Newswise — MEDFORD/SOMERVILLE, Mass. (February 27, 2013) – For the first 
> time, scientists have shown that transplanted eyes located far outside the 
> head in a vertebrate animal model can confer vision without a direct neural 
> connection to the brain.
> Biologists at Tufts University School of Arts and Sciences used a frog 
> model to shed new light – literally – on one of the major questions in 
> regenerative medicine, bioengineering, and sensory augmentation research. 
> "One of the big challenges is to understand how the brain and body adapt 
> to large changes in organization," says Douglas J. Blackiston, Ph.D., first 
> author of the paper "Ectopic Eyes Outside the Head in Xenopus Tadpoles 
> Provide Sensory Data For Light-Mediated Learning," in the February 27 issue 
> of the *Journal of Experimental Biology*. "Here, our research reveals the 
> brain's remarkable ability, or plasticity, to process visual data coming 
> from misplaced eyes, even when they are located far from the head.” 
> Blackiston is a post-doctoral associate in the laboratory of co-author 
> Michael Levin, Ph.D., professor of biology and director of the Center for 
> Regenerative and Developmental Biology at Tufts University. 
> Levin notes, "A primary goal in medicine is to one day be able to restore 
> the function of damaged or missing sensory structures through the use of 
> biological or artificial replacement components. There are many 
> implications of this study, but the primary one from a medical standpoint 
> is that we may not need to make specific connections to the brain when 
> treating sensory disorders such as blindness." 
> In this experiment, the team surgically removed donor embryo eye 
> primordia, marked with fluorescent proteins, and grafted them into the 
> posterior region of recipient embryos. This induced the growth of ectopic 
> eyes. The recipients’ natural eyes were removed, leaving only the ectopic 
> eyes.
> Fluorescence microscopy revealed various innervation patterns but none of 
> the animals developed nerves that connected the ectopic eyes to the brain 
> or cranial region. 
> To determine if the ectopic eyes conveyed visual information, the team 
> developed a computer-controlled visual training system in which quadrants 
> of water were illuminated by either red or blue LED lights. The system 
> could administer a mild electric shock to tadpoles swimming in a particular 
> quadrant. A motion tracking system outfitted with a camera and a computer 
> program allowed the scientists to monitor and record the tadpoles' motion 
> and speed. 
> Eyes See Without Wiring to Brain
> The team made exciting discoveries: Just over 19 percent of the animals 
> with optic nerves that connected to the spine demonstrated learned 
> responses to the lights. They swam away from the red light while the blue 
> light stimulated natural movement.
> Their response to the lights elicited during the experiments was no 
> different from that of a control group of tadpoles with natural eyes 
> intact. Furthermore, this response was not demonstrated by eyeless tadpoles 
> or tadpoles that did not receive any electrical shock.
> "This has never been shown before," says Levin. "No one would have guessed 
> that eyes on the flank of a tadpole could see, especially when wired only 
> to the spinal cord and not the brain."
> The findings suggest a remarkable plasticity in the brain’s ability to 
> incorporate signals from various body regions into behavioral programs that 
> had evolved with a specific and different body plan. 
> "Ectopic eyes performed visual function," says Blackiston. "The brain 
> recognized visual data from eyes that impinged on the spinal cord. We still 
> need to determine if this plasticity in vertebrate brains extends to 
> different ectopic organs or organs appropriate in different species."
> One of the most fascinating areas for future investigation, according to 
> Blackiston and Levin, is the question of exactly how the brain recognizes 
> that the electrical signals coming from tissue near the gut is to be 
> interpreted as visual data. 
> In computer engineering, notes Levin, who majored in computer science and 
> biology as a Tufts undergraduate, this problem is usually solved by a 
> "header"—a piece of metadata attached to a packet of information that 
> indicates its source and type. Whether electric signals from eyes impinging 
> on the spinal cord carry such an identifier of their origin remains a 
> hypothesis to be tested. 
> Research reported in this publication was supported by grants from the 
> National Institute of Mental Health of the National Institutes of Health 
> under award number MH081842-02 and the National Eye Institute, also of the 
> NIH, under award number EY018168, and the Forsyth Institute, under award 
> number 5T32DE007327-09. 
> Additional funders were the Leila Y. Mathers Charitable Foundation and the 
> U.S. Army Medical Research and Materiel Command (USAMRMC, award 
> W81XWH-10-2-0058).
> Blackiston, B. J. and Levin, M. (2013). Ectopic eyes outside the head in 
> Xenopus tadpoles provide sensory data for light-mediated learning.* J. 
> Exp. Biol.* 216, 1031-1040.

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