Talk:Mikhail Lebedev/Archive 1

Archive 1

ADDITIONAL INFORMATION

Journal covers

• [Journal of Neuroscience]
• [European Journal of Neuroscience]

Synopses of publications

Paying Attention to Memory

DOI: 10.1371/journal.pbio.0020407

Published: October 26, 2004

Copyright: © 2004 Public Library of Science. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Citation: (2004) Paying Attention to Memory. PLoS Biol 2(11): e407

If you could peer inside someone else's head, you'd see a scrunched-up gelatinous mass of tissue, weighing roughly a kilogram, homogeneous to the naked eye—in other words, a brain. The seeming uniformity of the overlying cerebral cortex, which has so outstripped other parts of the brain over the course of evolution that it makes up more than 80% of the brain, is belied by centuries of painstaking neuroscience. Some of the most compelling early evidence that parts of the cortex are specialized in their duties came from gun-shot wounds during the first world war. For instance, bullets lodged in the back of the brain disrupted sight in discrete portions of the visual scene, prompting insights into the localization and function of visual cortex.

The study of the front of the brain has a similar history of injury leading to insight. Phineas Gage, a railroad worker, had a 3.5-foot-long tamping iron blown straight through his frontal lobes and turned from a responsible, mild-mannered geek into an unruly exhibitionist overnight. Parts of the prefrontal cortex that he damaged have since been much studied for their involvement in motivation and emotional control.

More recent work has implicated other parts of the prefrontal cortex in working memory. Working memory is famously illustrated by your ability to temporarily remember a seven-digit telephone number, roughly the amount of information that you can store on-line in working memory for the duration of a task like phoning for a pizza.

Monkeys can be trained to remember information much like you remember a phone number, and then use the memory for gaining a reward (usually juice rather than pizza). They can learn to remember the specific location of a briefly flashed target on a screen and then, when cued, make an eye movement to look directly at that location. Previous research has shown that neurons in the prefrontal cortex maintain high rates of activity while monkeys remember the target location, and gradually the idea that the prefrontal cortex specializes in maintaining these transient memories has risen to dominance over other ideas about its functions.

In this issue of PLoS Biology, Mikhail Lebedev and his colleagues challenge this prevailing view with evidence that most prefrontal cortex neurons may not be so closely tied to working memory after all. As in previous research, they also trained monkeys to make an eye movement to a remembered target, but instead of only seeing one target, the monkeys saw two potential target locations during the course of the task. The monkeys had to pay attention to one of the potential targets, but this was not necessarily the one they would have responded to and was not the one they had to remember. To perform the task successfully, the animals had to engage their working memory, but most of the neurons the researchers recorded increased their activity selectively to the target that was the focus of attention.

Despite decades of research, the degree to which one region of the brain can be thought of as dedicated exclusively to a particular function is still much debated. These results do not refute the idea that the prefrontal cortex plays an important role in working memory. However, the authors suggest that this area may be more important in focusing the attention needed to remember that phone number, rather than actually holding that number in your mind.

Reference: Lebedev, M.A., Messinger, A., Kralik, J.D., Wise, S.P. (2004) Representation of attended versus remembered locations in prefrontal cortex. PLoS Biology, 2: 1919-1935.

Retraining the Brain to Recover Movement

DOI: 10.1371/journal.pbio.0000055

Published: October 13, 2003

Copyright: © 2003 Public Library of Science. This is an open-access article distributed under the terms of the Public Library of Science Open-Access License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Citation: (2003) Retraining the Brain to Recover Movement. PLoS Biol 1(2): e55

Some 200,000 people live with partial or nearly total permanent paralysis in the United States, with spinal cord injuries adding 11,000 new cases each year. Most research aimed at recovering motor function has focused on repairing damaged nerve fibers, which has succeeded in restoring limited movement in animal experiments. But regenerating nerves and restoring complex motor behavior in humans are far more difficult, prompting researchers to explore alternatives to spinal cord rehabilitation. One promising approach involves circumventing neuronal damage by establishing connections between healthy areas of the brain and virtual devices, called brain–machine interfaces (BMIs), programmed to transform neural impulses into signals that can control a robotic device. While experiments have shown that animals using these artificial actuators can learn to adjust their brain activity to move robot arms, many issues remain unresolved, including what type of brain signal would provide the most appropriate inputs to program these machines.

Monkey learns to control BMI

As they report in this paper, Miguel Nicolelis and colleagues have helped clarify some of the fundamental issues surrounding the programming and use of BMIs. Presenting results from a series of long-term studies in monkeys, they demonstrate that the same set of brain cells can control two distinct movements, the reaching and grasping of a robotic arm. This finding has important practical implications for spinal-cord patients—if different cells can perform the same functions, then surgeons have far more flexibility in how and where they can introduce electrodes or other functional enhancements into the brain. The researchers also show how monkeys learn to manipulate a robotic arm using a BMI. And they suggest how to compensate for delays and other limitations inherent in robotic devices to improve performance.

While other studies have focused on discrete areas of the brain—the primary motor cortex in one case and the parietal cortex in another—Nicolelis et al. targeted multiple areas in both regions to operate robotic devices, based on evidence indicating that neurons involved in motor control are found in many areas of the brain. The researchers gathered data on both brain signals and motor coordinates—such as hand position, velocity, and gripping force—to create multiple models for the BMI. They used different models according to which task the monkeys were learning—a reaching task, a hand-gripping task, and a reach-and-grasp task.

The BMI worked best, Nicolelis et al. show, when the programming models incorporated data recorded from large groups of neurons from both frontal and parietal brain regions, supporting the idea that each of these areas contains neurons directing multiple motor coordinates. When the researchers combined all the motor parameter models to optimize the control of the robotic arm through the BMI, they fixed those parameters and transferred control to the BMI and away from the monkeys' direct manipulation via a pole. The monkeys quickly learned that the robotic arm moved without their overt manipulations, and they periodically stopped moving their arms. Amazingly, when the researchers removed the pole, the monkeys were able to make the robotic arm reach and grasp without moving their own arms, though they did have visual feedback on the robotic arm's movements. Even more surprising, the monkeys' ability to manipulate the arm through “brain control” gradually improved over time.

One way the brain retains flexibility in responding to multiple tasks is through visual feedback. The researchers suggest that the success of the model may be the result of providing the monkeys with continuous feedback on their performance. This feedback may help integrate intention and action—including the action of the robotic arm—in the brain, allowing the monkey to get better at manipulating the robotic arm without moving.

By charting the relationship between neural signals and motor movements, Nicolelis et al. demonstrate how BMIs can work with healthy neural areas to reconfigure the brain's motor command neuronal elements and help restore intentional movement. These findings, they say, suggest that such artificial models of arm dynamics could one day be used to retrain the brain of a patient with paralysis, offering patients not only better control of prosthetic devices but the sense that these devices are truly an extension of themselves.

Reference: Carmena, J.M., Lebedev, M.A., Crist, R.E., O’Doherty, J.E., Santucci, D.M., Dimitrov, D.F., Patil, P.G., Henriquez, C.S., Nicolelis, M.A.L. (2003) Learning to control a brain-machine interface for reaching and grasping by primates. PLoS Biology, 1: 193-208.

The problem of vanity in articles about personalities

Recent discussion (see below) has shown that additions to Wikipedia pages that provide references to to the articles about personalities as well as initial versions of the pages heavily weighted to somebody's work can be perceived as vanity information. It appears that the way to cope with this problem is to make such revisions as neutral as possible, describe the reference's meaning rather than simply providing it and making even the initial drafts cover the topic more broadly. --Primate1 14:47, 16 December 2005 (UTC)

I've had this one on my watchlist for a few weeks. I do think the author is adding some vanity information to Wikipedia (for example, the article on Neural oscillations seems heavily weighted toward his work), but any author who has this many publications has a strong argument to notability. If this information is really false, let's put it through AfD at least. (and if this does turn out to be false, check out related articles, too--this would be widespread). --Dvyost 23:26, 17 October 2005 (UTC)

The Neural oscillations article currently is not heavily weighted toward Mikhail Lebedev's work. However, some improvements still will be needed. The article needs a discussion of oscillatory properties of single neurons, oscillatory discharges in sensory systems (early stages of visual processing, olfaction, etc.), as well as oscillations in deep brain structures such as basal ganglia. So, there is indeed room for improvement. --Primate1 14:36, 16 December 2005 (UTC)

The person who put a speedy deletion tag has been identifyied. I've identified the person who put the speedy deletion tag. That's a young man who did it as a joke. I just talked to him. I am removing this tag. As far as Neural oscillations, that's a matter of editing, reshaping and adding more information. Intrinsic neuronal properties, work on olfactory system -- all this should go there. Just give it some time and it will get better.

There seems to be a great deal of vanity edits going on. In articles on Neural Correlates of Consciousness, or Consciousness this author is simply adding a citation to his own paper or listing himself as a notable person in the study of consciousness. This is a clear example of vanity publishing and one of the reasons why Wikipedia gets a bad reputation. patrickw 17:51, 15 December 2005 (UTC)

How is adding a reference to published work a "vanity"? If you think that more references should be added or this particular reference does not cover the topic, simply make your edits. And I am not sure I agree with your explanation of how Wikipedia gets its "bad reputation". Wikipedia articles can be improved only one way: if experts and professionals work on them. By the way, "vanity" is one of the motivating factors for the experts. So, vanity in low doses is not such a bad thing... --Primate1 18:20, 15 December 2005 (UTC)

I agree that these appear to be largely vanity edits designed to promote Mikhail Lebedev rather than promote a thorough understanding of say, consciousness, or neural correlates of consciousness, etc. On the other hand he's clearly made some legitimate contributions, regardless of their exaggerated emphasis here, and possibly should be cited as a reference to some of these articles. This is a bit too far out of my field for me to try to edit it back to a fair balance myself. If you're more knowledgable in this area, I say go for it. --Dvyost 18:29, 15 December 2005 (UTC)

Encephalonseven just pointed out to me, correctly I think, that what I just wrote isn't quite fair. Lebedev has obviously done a lot of important work on this topic and probably should be included in all of these articles. However, I have to admit that seeing someone add a substantial amount of information about a single neuroscientist across our neurology articles does make me leery; I suppose all I'm trying to say is that I'd like to see someone with a clearly unrelated account doublecheck this for accuracy and proportion. Anyway, my apologies if this wasn't quite clear from my comment. --Dvyost 18:51, 15 December 2005 (UTC)

If I understand the idea correctly, the articles are supposed to grow in an incremental way. It is unrealistic to expect that a volunteer would write a comprehensive review that covers everything that has been done in a given field. And this is not how Wikipedia is supposed to work. Take the article Neural ensemble as an example. In its current form, it provides a good overview of the topic and does put any emphasis on a "single neuroscientist". Recently, the following paragraph was added: "The emergence of specific neural assemblies is thought to provide the functional elements of brain activity that execute the basic operations of informational processing (see Fingelkurts An.A. and Fingelkurts Al.A., 2004; 2005)", indicating that some other neuroscientists read the article and revised it to provide more information. This tendency is likely to continue, eventually resulting in a fairly uniform and balanced coverage of the topic. Of course, participants' initiative has a role, and individual players would tend to bias the articles according to their opinions. Given the open access and articles' editability, this is not a significant problem. I do not think that deleting some solid information (e.g., deletion by Patrickwilken of the reference to articles published in PLoS Biology at the PLoS Biology page) is a good way to improve the articles. Such deletions work according the principle: "This article is unbalanced. Let's delete it to make it balanced". Say, if the article on automobile contained a single reference to Ford, would it mean that Ford should be deleted? Such deletetion would make the article more balanced, but would not improve its quality as an encyclopedia article. The implulse to delete in such cases only reflects impatience. Evolution of the articles is a long process that requires time, patience and multiple edits. --Primate1 20:15, 15 December 2005 (UTC)

its a vanity edit if all you are doing is adding yourself into the article. If all you have to say about say neural correlates of consciousness is that you have a paper than that's a blatant vanity edit. If you were work is so important let someone else add it, and why don't you try adding some other people's work in. I have to say as someone who has been very involved in the field that this paper is not well known and that there are many better known papers around. patrickw 15:21, 16 December 2005 (UTC)

The paper you are talking about is a review article that covers a number of problems directly related to the issue of neural correlate of consciousness. It provides lots of references to other people's work. However, your criticism is well taken, and I will try to write a more balanced paragraph. --EncephalonSeven 15:39, 16 December 2005 (UTC)

The paper you are referring to is in a minor journal and has only been cited twice since it was published, and only then by the authors. So yes I think this is a vanity edit and I have removed it from the page again. If you cite so many other works why don't you rewrite the page to talk about them? patrickw 15:52, 16 December 2005 (UTC)

Please read my response attentively before responding. Didn't I say that I would rewrite the paragraph to provide a more balanced view? I trust you that you have good intentions, but objectively your deletions only leave certain authors that you consider important. Because of that, ironically, these particular edits appear as vanity. For example, after your deletions on one of the pages, only Logothesis was left as working on neural correlates of consciousness, whereas there are many others. I tried to fix this problem, and hopefully you will not ruin my work by your pointed deletions.

Since my name is not Logothetis I don't think leaving the leading monkey neuroscientist is a problem. Adding YOURSELF is an vanity edit. You are not meant to create pages about yourself, and add yourself into every possible article. If that's what you want to do you will be sorely disappointed when others come along and remove your edits. As I said elsewhere if you feel what I am doing is wrong I would be happy to talk to a third party. Shall we try to get one of the admins to weigh in on this? We could talk about all the pages you have been working through and adding your references to? patrickw 16:11, 16 December 2005 (UTC)

Sure. That's exactly how it is supposed to work: people read, and people revise the articles. The system should work!

I actually am an admin, but I'm not sure that really qualifies me to help too much as I don't know c*** about this subject (mostly, admin powers just let me fix more vandalism). I can offer one suggestion that might clear this right up, though. Why not move all, or at least most, of the references to these papers into footnotes? That would be more appropriate in terms of Wikipedia style, and would shift the focus of the articles away from individual publications to the concept of "neural oscillations" and what-have-you itself. Individual references to major papers (such as one that initially coined the term, or forever changed the field) could obviously remain, but as the primary purpose is to detail the subject itself, this might help de-clutter the articles. How would that sound to both of you? --Dvyost 19:04, 17 December 2005 (UTC)

The problem with making the neural oscillations article the fundamental knowledge article is that this question is very far from being resolved. Because of that, you cannot really resolve this issue by removing the references to the particular persons. Some think that brain oscillations are really important, others consider them an epiphenomenon. The ones who think that oscillations are important cannot agree on their function an so on. This is a developing field, so I think that the article can be improved in only one way: if more people add information and published research. In my opinion, it would help the reader if he/she can get some information about the people who are involved in this research. As far as the articles on consciousness and neural correlate, I can certainly understand the surprise of partrickw that someone else wanted to add to the subject beyond the circle of his acquientances, his subfield and the literature that he knows. However, he was too fast to make conclusions about the expertise of these people and their importance in the field. This is ubsolutely understandable given the general perception that Wikipedia is under constant attacks by vandals and people with 'evil intentions'. This perception also explains patrickw's comments which are borderline with personal attacks. Regarding the issue of "vanity", we have to decide if we want to live in the real or imaginary world. In imaginary world, there are certainly individuals who want to promote knowledge independent of their own ambitions. In the real world, motivating factors are much less idealistic. However, I do not see any problem here. How does it make any difference if someone points to his own publications that are relevant to the topic? Self-citing is a common practice in scientific literature, so why weekipedia would want to reinvent the wheel? Overall, wikipedia articles on neuroscience look very underdeveloped. So, should we waste time on discussion of peripheral issues? --EncephalonSeven 01:03, 18 December 2005 (UTC)