Saturday, May 16, 2009

Legal Highs

The past couple of weeks has seen British newspapers and politicians fretting about "legal highs". Legal highs are perfectly legal substances that "help people get out of their minds yet stay within the law" as the Guardian puts it.

Like Ritalin and booze, you mean? No, they're talking about things like
spice arctic synergy. You know, spice arctic synergy, the famous drug. No? Well, you know about it now, and so does everyone who reads the Guardian. I would be interested to see what the sales of spice arctic synergy are like in the next few weeks.

From what I can tell "spice" is just the latest of the many brands of "herbal highs" that can be bought in head shops and other such "alternative" retailers. Other famous brands are Druid's Fantasy, Aztec Acid, and Wizard's Willy. (I may have made some of those up.) These are blends of possibly psychoactive plants which can be smoked or eaten; the effects are supposedly a bit like cannabis or magic mushrooms but, at least so far as I'm told, mostly consist of nausea and headache. And wasting £20.

The consumer base for these silly products largely consists of teenagers who aren't cool enough to buy any proper drugs. On the drug credibility scale, most "legal highs" rank somewhere between sniffing glue and drinking your own pee after taking mushrooms in order to recapture some of the hallucinogens. (That works, allegedly.) No self-respecting drug user would be seen dead with any. Ban them, on the other hand, and everyone will want some.

To be fair, there are some genuinely potent legal drugs out there. Salvia divinorum, for example, contains a pharmacologically unique dissociative hallucinogen called salvinorin. Back when I was an uncool teenager a few friends of mine tried it, but they only ever took it once. The experience apparently amounted to ten minutes of terror and indescribable visions that seem to last hours; no-one I know who's taken it enjoyed it, and in the case of one of them it let him to vow never to take any hallucinogens ever again. I tried some, but it did nothing at all (except waste my money.) So it's a bit unpredictable.

Should it be banned? Maybe. It's certainly not stuff I would want my kids to go near, if I had any. Hypocritical as that might be. But that doesn't mean it's actually harmful, still less that prohibiting it would prevent harm overall (I suspect people would just find another drug to take, maybe an even dodgier one.) It would be worth a serious and evidence-based look, like all areas of drug policy, but given that the government have a history of hysterical shrieking whenever their own appointed experts try to do that, I'm not hopeful.

And when I read that one MP has made it his personal mission to stop Salvia, I just couldn't stop thinking of bisturbile cranabolic amphetamoids.

Legal Highs

The past couple of weeks has seen British newspapers and politicians fretting about "legal highs". Legal highs are perfectly legal substances that "help people get out of their minds yet stay within the law" as the Guardian puts it.

Like Ritalin and booze, you mean? No, they're talking about things like
spice arctic synergy. You know, spice arctic synergy, the famous drug. No? Well, you know about it now, and so does everyone who reads the Guardian. I would be interested to see what the sales of spice arctic synergy are like in the next few weeks.

From what I can tell "spice" is just the latest of the many brands of "herbal highs" that can be bought in head shops and other such "alternative" retailers. Other famous brands are Druid's Fantasy, Aztec Acid, and Wizard's Willy. (I may have made some of those up.) These are blends of possibly psychoactive plants which can be smoked or eaten; the effects are supposedly a bit like cannabis or magic mushrooms but, at least so far as I'm told, mostly consist of nausea and headache. And wasting £20.

The consumer base for these silly products largely consists of teenagers who aren't cool enough to buy any proper drugs. On the drug credibility scale, most "legal highs" rank somewhere between sniffing glue and drinking your own pee after taking mushrooms in order to recapture some of the hallucinogens. (That works, allegedly.) No self-respecting drug user would be seen dead with any. Ban them, on the other hand, and everyone will want some.

To be fair, there are some genuinely potent legal drugs out there. Salvia divinorum, for example, contains a pharmacologically unique dissociative hallucinogen called salvinorin. Back when I was an uncool teenager a few friends of mine tried it, but they only ever took it once. The experience apparently amounted to ten minutes of terror and indescribable visions that seem to last hours; no-one I know who's taken it enjoyed it, and in the case of one of them it let him to vow never to take any hallucinogens ever again. I tried some, but it did nothing at all (except waste my money.) So it's a bit unpredictable.

Should it be banned? Maybe. It's certainly not stuff I would want my kids to go near, if I had any. Hypocritical as that might be. But that doesn't mean it's actually harmful, still less that prohibiting it would prevent harm overall (I suspect people would just find another drug to take, maybe an even dodgier one.) It would be worth a serious and evidence-based look, like all areas of drug policy, but given that the government have a history of hysterical shrieking whenever their own appointed experts try to do that, I'm not hopeful.

And when I read that one MP has made it his personal mission to stop Salvia, I just couldn't stop thinking of bisturbile cranabolic amphetamoids.

Friday, May 15, 2009

Science vs. Free Will, Again

The question of whether we have "free will" has kept philosophers occupied for at least 2000 years. Wouldn't it be nice if science came along and sorted the whole thing out?
That's the reason why so many people are excited about reports like the one just published in Science, Movement Intention After Parietal Cortex Stimulation in Humans. The report itself is extremely straightforward. The authors, a team of French neurosurgeons, used electrodes to stimulate various points on the surface of the brains of seven patients. The patients were all suffering from brain tumours in various places, and they were undergoing surgery to remove them. As often happens, the authors decided to try to squeeze a little research out of the procedure as well.

The authors stimulated points in various areas of the brain, but the most interesting results came from the premotor cortex (the blue area on the picture above) and the posterior parietal cortex (red and yellow).

When certain points on the premotor cortex were stimulated, the patients moved. But they were not aware that they had done so. For example:
...during stimulation patient PM1 exhibited a large multijoint movement involving flexion of the left wrist, fingers, and elbow ... He did not spontaneously comment on this, and when asked whether he had felt a movement he responded negatively.
That's pretty interesting in itself, but even more so is what happened when the posterior parietal cortex got zapped. Stimulation here produced a desire or intention to move, although no movement actually occured:
Stimulation of all these sites produced a pure intention, that is, a felt desire to move without any overt movement being produced... Without prompting by the examiner, all three patients spontaneously used terms such as “will,” “desire,” and “wanting to,” which convey the voluntary character of the movement intention and its attribution to an internal source, that is, located within the self.
And as if that wasn't enough philosophically-provocative fun, high intensity stimulation of the same area made the patients believe that they had in fact moved, although they didn't move a muscle:
[with higher electrode currents] conscious motor intentions were replaced by a sensation that a movement had been accomplished [but] no actual movement was observed. Thus, these patients experienced awareness of an illusory movement. For example, patient PP3 reported after low-intensity stimulation of one site (5 mA, 4 s; site a in Fig. 1), “I felt a desire to lick my lips” and at a higher intensity (8 mA, 4 s), “I moved my mouth, I talked, what did I say?”
Wow. What are we to make of all this?

A while back I wrote about Wilder Penfield's idea of "double conciousness" which Christian neurosurgeon Michael Egnor described approvingly as
Penfield found that he could invoke all sorts of things- movements, sensations, memories. But in every instance (hundreds of thousands of individual stimulations- in different locations in each patient- during his career), the patients were aware that the stimulation was being done to them, but not by them. There was a part of the mind that was independent of brain stimulation and that constituted a part of subjective experience that Penfield was not able to manipulate with his surgery.

Penfield called this "double consciousness", meaning that there was a part of subjective experience that he could invoke or modify materially, and a different part that was immune to such manipulation.
So Penfield, one of the great pioneers of 20th century neuroscience, claimed that stimulation of the brain could never produce desires or intentions which were experienced as the subject's "own". The person whose brain you were stimulating always felt that whatever happened to them came from outside.

But this French report directly contradicts that. We can only speculate as to why. It could be that Penfield just never hit the right spot, but this seems extremely unlikely, as he did a lot of stimulating over the course of his career. A cynic might ask whether Penfield did observe similar phenomena and just never reported them, but if we're going to go down that road, it's equally likely that these neurosurgeons just made it all up. Fortunately, any neurosurgeon should be able to try to replicate these results with a few prods of an electrode, so it shouldn't take long before the truth becomes clearer.

If these present results hold up, they'll certainly suggest some interesting ideas about the organisation of the brain - such as that the perception of movement depends upon the neurones encoding the intention to move rather than those involved in producing the actual motor act.

It would also be interesting to find out what happens when you simulataneously stimulate the premotor spot which makes your arm move, and the posterior parietal spot which makes you want to move your arm. Would that make you want to move your arm - and do so? If so, that would suggest that something very similar to that is going on whenever we do anything. What is life, but wanting to move, and moving?

But whether that's true or not, intentions (and everything else) are still something that happens in the brain, and the brain is a material object subject to the laws of physics. Neuroscience can tell us how exactly it all fits together, but at the end of the day, it's all a bunch of cells. Free will, in other words, appears to be in trouble, whatever the details of the brain's mechanisms happen to be.

ResearchBlogging.orgDesmurget, M., Reilly, K., Richard, N., Szathmari, A., Mottolese, C., & Sirigu, A. (2009). Movement Intention After Parietal Cortex Stimulation in Humans Science, 324 (5928), 811-813 DOI: 10.1126/science.1169896

Science vs. Free Will, Again

The question of whether we have "free will" has kept philosophers occupied for at least 2000 years. Wouldn't it be nice if science came along and sorted the whole thing out?
That's the reason why so many people are excited about reports like the one just published in Science, Movement Intention After Parietal Cortex Stimulation in Humans. The report itself is extremely straightforward. The authors, a team of French neurosurgeons, used electrodes to stimulate various points on the surface of the brains of seven patients. The patients were all suffering from brain tumours in various places, and they were undergoing surgery to remove them. As often happens, the authors decided to try to squeeze a little research out of the procedure as well.

The authors stimulated points in various areas of the brain, but the most interesting results came from the premotor cortex (the blue area on the picture above) and the posterior parietal cortex (red and yellow).

When certain points on the premotor cortex were stimulated, the patients moved. But they were not aware that they had done so. For example:
...during stimulation patient PM1 exhibited a large multijoint movement involving flexion of the left wrist, fingers, and elbow ... He did not spontaneously comment on this, and when asked whether he had felt a movement he responded negatively.
That's pretty interesting in itself, but even more so is what happened when the posterior parietal cortex got zapped. Stimulation here produced a desire or intention to move, although no movement actually occured:
Stimulation of all these sites produced a pure intention, that is, a felt desire to move without any overt movement being produced... Without prompting by the examiner, all three patients spontaneously used terms such as “will,” “desire,” and “wanting to,” which convey the voluntary character of the movement intention and its attribution to an internal source, that is, located within the self.
And as if that wasn't enough philosophically-provocative fun, high intensity stimulation of the same area made the patients believe that they had in fact moved, although they didn't move a muscle:
[with higher electrode currents] conscious motor intentions were replaced by a sensation that a movement had been accomplished [but] no actual movement was observed. Thus, these patients experienced awareness of an illusory movement. For example, patient PP3 reported after low-intensity stimulation of one site (5 mA, 4 s; site a in Fig. 1), “I felt a desire to lick my lips” and at a higher intensity (8 mA, 4 s), “I moved my mouth, I talked, what did I say?”
Wow. What are we to make of all this?

A while back I wrote about Wilder Penfield's idea of "double conciousness" which Christian neurosurgeon Michael Egnor described approvingly as
Penfield found that he could invoke all sorts of things- movements, sensations, memories. But in every instance (hundreds of thousands of individual stimulations- in different locations in each patient- during his career), the patients were aware that the stimulation was being done to them, but not by them. There was a part of the mind that was independent of brain stimulation and that constituted a part of subjective experience that Penfield was not able to manipulate with his surgery.

Penfield called this "double consciousness", meaning that there was a part of subjective experience that he could invoke or modify materially, and a different part that was immune to such manipulation.
So Penfield, one of the great pioneers of 20th century neuroscience, claimed that stimulation of the brain could never produce desires or intentions which were experienced as the subject's "own". The person whose brain you were stimulating always felt that whatever happened to them came from outside.

But this French report directly contradicts that. We can only speculate as to why. It could be that Penfield just never hit the right spot, but this seems extremely unlikely, as he did a lot of stimulating over the course of his career. A cynic might ask whether Penfield did observe similar phenomena and just never reported them, but if we're going to go down that road, it's equally likely that these neurosurgeons just made it all up. Fortunately, any neurosurgeon should be able to try to replicate these results with a few prods of an electrode, so it shouldn't take long before the truth becomes clearer.

If these present results hold up, they'll certainly suggest some interesting ideas about the organisation of the brain - such as that the perception of movement depends upon the neurones encoding the intention to move rather than those involved in producing the actual motor act.

It would also be interesting to find out what happens when you simulataneously stimulate the premotor spot which makes your arm move, and the posterior parietal spot which makes you want to move your arm. Would that make you want to move your arm - and do so? If so, that would suggest that something very similar to that is going on whenever we do anything. What is life, but wanting to move, and moving?

But whether that's true or not, intentions (and everything else) are still something that happens in the brain, and the brain is a material object subject to the laws of physics. Neuroscience can tell us how exactly it all fits together, but at the end of the day, it's all a bunch of cells. Free will, in other words, appears to be in trouble, whatever the details of the brain's mechanisms happen to be.

ResearchBlogging.orgDesmurget, M., Reilly, K., Richard, N., Szathmari, A., Mottolese, C., & Sirigu, A. (2009). Movement Intention After Parietal Cortex Stimulation in Humans Science, 324 (5928), 811-813 DOI: 10.1126/science.1169896

Wednesday, May 13, 2009

Annotated Links #2

In the NY Times, Daphne Merkin writes about her life with recurrent and "treatment-resistant" depression. A Journey Through Darkness is eloquent and honest, but it offers no convincing explanations as to the origin of her bouts of melancholy. Sometimes she is depressed and then eventually the state passes. In Merkin's account, and in my personal experience, being depressed is a brute fact. It is experienced, not understood. To call it a "journey" or anything else which implies some kind of narrative is misleading. And when a depression passes, it goes with a whimper not a bang:
It was about 4:30, the time of day that, by mid-August, brings with it a whiff of summer’s end. I looked up into the startlingly blue sky; one of the dogs was sitting at my side, her warm body against my leg, drying me off after the swim I had recently taken. I could begin to see the curve of fall up ahead. There would be new books to read, new films to see and new restaurants to try. I envisioned myself writing again, and it didn’t seem like a totally preposterous idea. I had things I wanted to say. Everything felt fragile and freshly come upon, but for now, at least, my depression had stepped back, giving me room to move forward. I had forgotten what it was like to be without it, and for a moment I floundered, wondering how I would recognize myself. I knew for certain it would return, sneaking up on me when I wasn’t looking, but meanwhile there were bound to be glimpses of light if only I stayed around and held fast to the long perspective. It was a chance that seemed worth taking.
The Royal Swedish Academy of Sciences issues a welcome statement condemning "lie-detector" peddlers Nemesysco for their attempt to gag two Swedish scientists. (See also Ministry of Truth for an extensive take-down of Nemesysco and all who use their products). Although, given that this happened several months ago, they certainly took their time about it...
Incidents of this kind are a threat to research freedom and, by extension, to the free dissemination of information in society. Threats to sue must not be used to restrict scientific discussion.
Finally, I know I said I don't believe in music reviews, but Neko Case is brilliant.

Annotated Links #2

In the NY Times, Daphne Merkin writes about her life with recurrent and "treatment-resistant" depression. A Journey Through Darkness is eloquent and honest, but it offers no convincing explanations as to the origin of her bouts of melancholy. Sometimes she is depressed and then eventually the state passes. In Merkin's account, and in my personal experience, being depressed is a brute fact. It is experienced, not understood. To call it a "journey" or anything else which implies some kind of narrative is misleading. And when a depression passes, it goes with a whimper not a bang:
It was about 4:30, the time of day that, by mid-August, brings with it a whiff of summer’s end. I looked up into the startlingly blue sky; one of the dogs was sitting at my side, her warm body against my leg, drying me off after the swim I had recently taken. I could begin to see the curve of fall up ahead. There would be new books to read, new films to see and new restaurants to try. I envisioned myself writing again, and it didn’t seem like a totally preposterous idea. I had things I wanted to say. Everything felt fragile and freshly come upon, but for now, at least, my depression had stepped back, giving me room to move forward. I had forgotten what it was like to be without it, and for a moment I floundered, wondering how I would recognize myself. I knew for certain it would return, sneaking up on me when I wasn’t looking, but meanwhile there were bound to be glimpses of light if only I stayed around and held fast to the long perspective. It was a chance that seemed worth taking.
The Royal Swedish Academy of Sciences issues a welcome statement condemning "lie-detector" peddlers Nemesysco for their attempt to gag two Swedish scientists. (See also Ministry of Truth for an extensive take-down of Nemesysco and all who use their products). Although, given that this happened several months ago, they certainly took their time about it...
Incidents of this kind are a threat to research freedom and, by extension, to the free dissemination of information in society. Threats to sue must not be used to restrict scientific discussion.
Finally, I know I said I don't believe in music reviews, but Neko Case is brilliant.

Thursday, May 7, 2009

Lithium and Antidepressants in Tap Water

Lithium, as everyone knows, is a song by Nirvana. (It's also a different, and worse, song by Evanescence). It's also a chemical element. And it's a drug, used in psychiatry to treat bipolar disorder and, sometimes, severe depression.

One thing which lithium seems to do rather well - or at least better than other drugs - is make people less likely to commit suicide. At least, that's what most authorities say, so let's assume it's true.

Now a Japanese team report that the amount of lithium in tap water are negatively correlated with suicide rates - Lithium levels in drinking water and risk of suicide. (Someone has helpfully put this up on Scribd for people without academic access).

They analyzed the water supplies in the 18 subdivisions of Oita prefecture in southern Japan, and compared the lithium levels in the water with the average suicide rate (normalized for age and gender). Here's what happened -
Now, on paper that's a pretty solid correlation. But how believable is it? The maximum lithium level in the water was found to be 59 micrograms per liter. By contrast, if someone were taking lithium for bipolar disorder, they would on average be taking about 1 gram of lithium carbonate (Li2CO3) per day, which works out at about 100 mg of lithium (and 900 mg of inert carbonate).

Assuming that people drink about two liters of tap water per day (almost certainly they drink less), that's about 120 micrograms per day. That's 0.12 mg. So about a thousand-fold less than you'd take if you were bipolar.

Could such a tiny amount of lithium do anything? Well, maybe. It's not impossible that it would have some small effect on suicide rates, but it seems very unlikely that it would account for the difference between a rate of 120 and a rate of 80 which is what the graph seems to imply. The effect is just too large to be credible, if you ask me.

Although that said, another paper just out found that tiny amounts of antidepressants (the amounts that you find in rivers because so many people take them and some of them are stay in urine) could affect the behaviour of baby fish. And presumably also baby humans. Unfortunately I can't access this study, so I don't know whether that's nonsense or not, but it's food for thought.

ResearchBlogging.orgOhgami, H., Terao, T., Shiotsuki, I., Ishii, N., & Iwata, N. (2009). Lithium levels in drinking water and risk of suicide The British Journal of Psychiatry, 194 (5), 464-465 DOI: 10.1192/bjp.bp.108.055798