I do fMRI research, and I can tell you that this poster does not constitute a successful critique of modern fMRI methods.
The result reported here is only significant when not properly accounting for multiple comparisons or spatial extent. When the authors do use an appropriate method (such as False Discovery Rate), the poster reports that no voxels survive thresholding. In the vast majority of circumstances no one accepts a 3-voxel "activation" in fMRI precisely because they are likely to happen by chance alone.
The paper says: Identical t-contrasts controlling the false discovery rate (FDR) and familywise
error rate (FWER) were completed. These contrasts indicated no active
voxels, even at relaxed statistical thresholds (p = 0.25).
Basically, this shows that when you do your thresholding wrong, you get meaningless results. Nothing to see here.
fMRI is not a viable procedure to be performed involuntarily. It's very susceptible to movement artifacts, all you'd have to do is wobble your head and you screw everything up. The only way you could really force someone to comply would be to sedate them, in which case they aren't going to be answering questions.
The results of an MRI scan are composite images of increasing spatial resolution taken over a time span of minutes to tens of minutes. If a person's "liar region" of the brain lit up during a scan, that only means that region was active at some point during the scan, which could have occurred for any number of reasons during that time span.
This is poor characterization of how fMRI works. fMRI is not a "composite of increasing spatial resolution over a times span of minutes". Rather, an entire image of the brain is acquired very quickly, about every 2 seconds, and the timecourse of change in those images is statistically compared to the changes in activity of the subject during that time. For example, in a study like this you would look for signal changes that were correlated with the lying events compared with the honest events.
Seconds are long in terms of psychological time, but you design the timing of experiment in such a way that allows you to compare among the conditions of interest.
It's not unreasonable to predict the results of an election with a random sample. For instance, if you are a news organization you may want to do this. However, the official results should not be based on a prediction, they should be the actual counted results. Statistical predictions have a chance of being wrong.
Furthermore, the idea of "random" sample is pretty far-fetched when you are counting votes from certain locations and the proportion of votes for each candidates varied by location. Once you have enough information to take a truly random sample you also have enough information to actually count the votes.
Sure, but the misconception is that the game of poker fairly played favors the house. People erroneously believe this because they relate it to other forms of gambling where this is the case.
Cheating is another issue, and it's true the we need better regulations on this -- which is part of the reason the law should be changed or clarified. That said, what has kept things above water so far (with a few notable exceptions like the scandal at Absolute Poker) is that the money these sites make from rake is enormous. The motivation to attract more players with a reputation of fairness is really the best way for them to make money. Cheating the very high limit players is pretty much the only way this could go down -- which is what happened at AP, where they were caught when people noticed the anomalous winnings of certain players.
First, you ahve no garuntee you will get paid.
second, you ahve no way of knowing if it's fair.
You can skew the odds 10% in the houses favor, and no one would notice. probably more.
The persistence of these myths is quite remarkable, and may have something to do with the current legal situation.
As others have pointed out, poker is not a game which is skewed in the house's favor. The house takes a percentage of every pot, called the rake. In poker players play against one another, and while there is a chance element, chance does not favor anyone in the long run. In the long run, the difference in earnings between two players can be attributed to the choices they make. That is why poker is considered a game of skill and many governments have recognized this distinction. Poker is legal in California, for example, because the courts have ruled it to be a game of skill.
What is especially silly about this new legal move is that it rests on very shaky legal ground. The prosecutor has cited the Wire Act, but federal courts have already ruled that the wire act only applies to sports betting. It's also strange timing since the UIGEA which attempts to prevent gambling-related money transfers is scheduled to begin being enforced later this year.
As to the fairness of the games, that could only be ensured and improved with proper regulation. Hopefully the attention brought to this situation by this case will ultimately result in the legality of online poker being clarified. Barney Frank has introduced a bill to legalize and regulate online poker. If this is an issue you support, I urge you to let your congressperson know.
How much longer till we can figure out how our brain "codes" things then exploit it for our own benefit?
We have already begun to do this. For example, understanding the binocular cues for depth perception have given us 3D movies that provide us with the illusion of depth. Providing input to the the brain directly may eventually be more efficient than presenting sensory information through our sensory apparatus, but probably not for a long time. For providing fictional experiences I think it's still going to be more practical to use the eyes and the ears compared with the auditory and visual cortices for quite a while.
The signals in that video are recorded from the scalp. Basically when you filter the electrical signals from the brain through the skull you lose a lot of spatial resolution. Given that spatial maps are one important way the brain encodes information having the electrodes actually on the surface of the brain makes a huge difference in the amount of information you have access to.
That said, this is not really a new technology, merely a new application of electrocorticography. Non-invasive it is not, since it involves opening up the skull. It's only "less invasive" compared with poking an electrode deep into the brain.
More related to why you can't tickle yourself. It is pretty well established now that the brain is in the business of predicting sensory events. With regards to touch, the activations in somatosensory cortex are very similar when you anticipate touch compared with when you actually experience it.
In fact the kind of phantom limb studied in this article is not the kind most people are familiar with, due to amputation. This is a "supernumerary phantom limb". In SPL, the patient still has both arms, but after stroke experiences a third, additional arm. The nice thing about this methodologically is that they can compare imagination of movements with the existing paralyzed arm to the experienced movements of the SPL. How much of this applies to the more "typical" phantom limb is an important question.
OK. Yeah I saw the 60 minutes episode and it wasn't clear if they were using a pre-existing model or not.
I believe you if it was in the presentation, but in general that is *much* harder problem since you can't really get voxel to voxel correspondence when registering brains across people.
It seems as though two people thinking about a given noun (e.g. a hammer) really have similarities in their fMRI patterns.
I'm pretty sure this research doesn't say that. A separate computational model was computed for each individual subject. The successful ability to predict which noun they were thinking about is for that individual person only.
fMRI does not measure changes in glucose metabolism, it measures changes in blood oxygenation.
Re:Offered his brain for further scientific study
on
The Unforgettable Amnesiac
·
· Score: 4, Informative
Yes, H.M. was aware of his condition, which is typical of temporal lobe amnesia. (Patients who also have damage to the frontal lobes as in Korsakoff's syndrome are often unaware of their memory deficit, a form of anosognosia.)
One of the quotes from H.M. I always read in my neuroscience classes:
"Right now I'm wondering, have I done or said anything amiss? You see, at this moment everything looks clear to me, but what happened just before? That's what worries me. It's like waking from a dream; I just don't remember.... Every day is alone in itself, whatever enjoyment I've had, whatever sorrow."
There were not hundreds of accounts, but there were several.
Some of them were identified by anomalous statistics, but some were caught by following the money transfers among accounts. At some point a "good samaritan" from inside the company posted some transfer histories to the forum where this was being investigated, which allowed some of the dots to be connected.
Also, most of the sites supposedly have their software written so that they can always look back after the fact and examine the hand histories for collusion, but no one can access the hole cards while a hand is live.
Casino gambling in general is a sucker bet (even under strict conditions the odds always favor the house), but online gaming and other unregulated gambling is ESPECIALLY so
This is exactly how poker differs from other casino games. Since players play against each other, the game is not biased against anyone. The house takes a cut of each pot (the rake), but skill determines who wins in the long run. For example, here in California poker is legal while other gambling games are not since it is considered a game of skill.
I do however agree with the need for regulation. I've been following this particular case from the beginning and the scary part is that nothing would have been uncovered if it weren't for the diligence of the players, who discovered the anomalies in several player's statistics, dug deeper and deeper to find the facts, and then pressed and pressed these companies to hold them accountable. Russ Hamilton, the cheater behind the scenes is a former World Series of Poker winner who was one of the founders of Ultimate Bet and seems to have set this whole scheme up from the beginning.
It's even worse than that, the iPhone keeps copies of all your emails, and records phone numbers you have called as well as keeping a database of all your personal contacts!!! The thing is a 5 ounce privacy invasion machine!
Slashdot Mirror
I do fMRI research, and I can tell you that this poster does not constitute a successful critique of modern fMRI methods.
The result reported here is only significant when not properly accounting for multiple comparisons or spatial extent. When the authors do use an appropriate method (such as False Discovery Rate), the poster reports that no voxels survive thresholding. In the vast majority of circumstances no one accepts a 3-voxel "activation" in fMRI precisely because they are likely to happen by chance alone.
The paper says: Identical t-contrasts controlling the false discovery rate (FDR) and familywise error rate (FWER) were completed. These contrasts indicated no active voxels, even at relaxed statistical thresholds (p = 0.25).
Basically, this shows that when you do your thresholding wrong, you get meaningless results. Nothing to see here.
fMRI is not a viable procedure to be performed involuntarily. It's very susceptible to movement artifacts, all you'd have to do is wobble your head and you screw everything up. The only way you could really force someone to comply would be to sedate them, in which case they aren't going to be answering questions.
This is poor characterization of how fMRI works. fMRI is not a "composite of increasing spatial resolution over a times span of minutes". Rather, an entire image of the brain is acquired very quickly, about every 2 seconds, and the timecourse of change in those images is statistically compared to the changes in activity of the subject during that time. For example, in a study like this you would look for signal changes that were correlated with the lying events compared with the honest events.
Seconds are long in terms of psychological time, but you design the timing of experiment in such a way that allows you to compare among the conditions of interest.
Is it a crime? I mean to ask if there are laws that prevent this form of accounting, or if it is just a sleazy loophole which is not in fact criminal.
The upgrade to 3.0 is free.
You could be walking backwards.
(i should have said 'representative' sample, not 'random' sample)
It's not unreasonable to predict the results of an election with a random sample. For instance, if you are a news organization you may want to do this. However, the official results should not be based on a prediction, they should be the actual counted results. Statistical predictions have a chance of being wrong.
Furthermore, the idea of "random" sample is pretty far-fetched when you are counting votes from certain locations and the proportion of votes for each candidates varied by location. Once you have enough information to take a truly random sample you also have enough information to actually count the votes.
I believe the concern is that the house may cheat by having players with access to the hole cards.
Sure, but the misconception is that the game of poker fairly played favors the house. People erroneously believe this because they relate it to other forms of gambling where this is the case.
Cheating is another issue, and it's true the we need better regulations on this -- which is part of the reason the law should be changed or clarified. That said, what has kept things above water so far (with a few notable exceptions like the scandal at Absolute Poker) is that the money these sites make from rake is enormous. The motivation to attract more players with a reputation of fairness is really the best way for them to make money. Cheating the very high limit players is pretty much the only way this could go down -- which is what happened at AP, where they were caught when people noticed the anomalous winnings of certain players.
The persistence of these myths is quite remarkable, and may have something to do with the current legal situation.
As others have pointed out, poker is not a game which is skewed in the house's favor. The house takes a percentage of every pot, called the rake. In poker players play against one another, and while there is a chance element, chance does not favor anyone in the long run. In the long run, the difference in earnings between two players can be attributed to the choices they make. That is why poker is considered a game of skill and many governments have recognized this distinction. Poker is legal in California, for example, because the courts have ruled it to be a game of skill.
What is especially silly about this new legal move is that it rests on very shaky legal ground. The prosecutor has cited the Wire Act, but federal courts have already ruled that the wire act only applies to sports betting. It's also strange timing since the UIGEA which attempts to prevent gambling-related money transfers is scheduled to begin being enforced later this year.
As to the fairness of the games, that could only be ensured and improved with proper regulation. Hopefully the attention brought to this situation by this case will ultimately result in the legality of online poker being clarified. Barney Frank has introduced a bill to legalize and regulate online poker. If this is an issue you support, I urge you to let your congressperson know.
We have already begun to do this. For example, understanding the binocular cues for depth perception have given us 3D movies that provide us with the illusion of depth. Providing input to the the brain directly may eventually be more efficient than presenting sensory information through our sensory apparatus, but probably not for a long time. For providing fictional experiences I think it's still going to be more practical to use the eyes and the ears compared with the auditory and visual cortices for quite a while.
The signals in that video are recorded from the scalp. Basically when you filter the electrical signals from the brain through the skull you lose a lot of spatial resolution. Given that spatial maps are one important way the brain encodes information having the electrodes actually on the surface of the brain makes a huge difference in the amount of information you have access to.
That said, this is not really a new technology, merely a new application of electrocorticography. Non-invasive it is not, since it involves opening up the skull. It's only "less invasive" compared with poking an electrode deep into the brain.
More related to why you can't tickle yourself. It is pretty well established now that the brain is in the business of predicting sensory events. With regards to touch, the activations in somatosensory cortex are very similar when you anticipate touch compared with when you actually experience it.
In fact the kind of phantom limb studied in this article is not the kind most people are familiar with, due to amputation. This is a "supernumerary phantom limb". In SPL, the patient still has both arms, but after stroke experiences a third, additional arm. The nice thing about this methodologically is that they can compare imagination of movements with the existing paralyzed arm to the experienced movements of the SPL. How much of this applies to the more "typical" phantom limb is an important question.
OK. Yeah I saw the 60 minutes episode and it wasn't clear if they were using a pre-existing model or not.
I believe you if it was in the presentation, but in general that is *much* harder problem since you can't really get voxel to voxel correspondence when registering brains across people.
I'm pretty sure this research doesn't say that. A separate computational model was computed for each individual subject. The successful ability to predict which noun they were thinking about is for that individual person only.
fMRI does not measure changes in glucose metabolism, it measures changes in blood oxygenation.
Yes, H.M. was aware of his condition, which is typical of temporal lobe amnesia. (Patients who also have damage to the frontal lobes as in Korsakoff's syndrome are often unaware of their memory deficit, a form of anosognosia.)
One of the quotes from H.M. I always read in my neuroscience classes:
"Right now I'm wondering, have I done or said anything amiss? You see, at this moment everything looks clear to me, but what happened just before? That's what worries me. It's like waking from a dream; I just don't remember.... Every day is alone in itself, whatever enjoyment I've had, whatever sorrow."
RIP, Henry.
Is it possible he has access because he's a senator?
There were not hundreds of accounts, but there were several.
Some of them were identified by anomalous statistics, but some were caught by following the money transfers among accounts. At some point a "good samaritan" from inside the company posted some transfer histories to the forum where this was being investigated, which allowed some of the dots to be connected.
Also, most of the sites supposedly have their software written so that they can always look back after the fact and examine the hand histories for collusion, but no one can access the hole cards while a hand is live.
This is exactly how poker differs from other casino games. Since players play against each other, the game is not biased against anyone. The house takes a cut of each pot (the rake), but skill determines who wins in the long run. For example, here in California poker is legal while other gambling games are not since it is considered a game of skill.
I do however agree with the need for regulation. I've been following this particular case from the beginning and the scary part is that nothing would have been uncovered if it weren't for the diligence of the players, who discovered the anomalies in several player's statistics, dug deeper and deeper to find the facts, and then pressed and pressed these companies to hold them accountable. Russ Hamilton, the cheater behind the scenes is a former World Series of Poker winner who was one of the founders of Ultimate Bet and seems to have set this whole scheme up from the beginning.
I read TFA and I still have no idea what the legal basis of this claim is. Does anyone have any idea on what grounds they are suing?
It's even worse than that, the iPhone keeps copies of all your emails, and records phone numbers you have called as well as keeping a database of all your personal contacts!!! The thing is a 5 ounce privacy invasion machine!