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November 19, 2005

BehindTheMedspeak: Why can't brain scans see depression?

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For the longest time now, we've been told that the wondrous advances in imaging technology of recent years will make the diagnosis and subsequent focused, quantifiably effective–or–not treatment of depression a reality.

And yet we are no closer now than we were before the decade of the brain began.

It ended in 2000, by the way, with most such promises unkept.

Why?

Because it turns out that the markers for depression — if they even exist — are far more elusive than anyone had reason to believe they would be.

Benedict Carey wrote an excellent article for the October 18 New York Times Science section headlined, "Can Brain Scans See Depression?"

Long answer short: no.

Here's Carey's excellent piece.

    Can Brain Scans See Depression?

    They seem almost alive: snapshots of the living human brain.

    Not long ago, scientists predicted that these images, produced by sophisticated brain-scanning techniques, would help cut through the mystery of mental illness, revealing clear brain abnormalities and allowing doctors to better diagnose and treat a wide variety of disorders.

    And nearly every week, it seems, imaging researchers announce another finding, a potential key to understanding depression, attention deficit disorder, anxiety.

    Yet for a variety of reasons, the hopes and claims for brain imaging in psychiatry have far outpaced the science, experts say.

    After almost 30 years, researchers have not developed any standardized tool for diagnosing or treating psychiatric disorders based on imaging studies.

    Several promising lines of research are under way.

    But imaging technology has not lived up to the hopes invested in it in the 1990's - labeled the "Decade of the Brain" by the American Psychiatric Association - when many scientists believed that brain scans would turn on the lights in what had been a locked black box.

    Now, with imaging studies being published at a rate of more than 500 a year, and commercial imaging clinics opening in some parts of the country, some experts say that the technology has been oversold as a psychiatric tool.

    Other researchers remain optimistic, but they wonder what the data add up to, and whether it is time for the field to rethink its approach and its expectations.

    "I have been waiting for my work in the lab to affect my job on the weekend, when I practice as a child psychiatrist," said Dr. Jay Giedd, chief of brain imaging in the child psychiatry branch at the National Institute of Mental Health, who has done M.R.I. scans in children Monday through Friday for 14 years.

    "It hasn't happened. In this field, every year you hear, 'Oh, it's more complicated than we thought.' Well, you hear that for 10 years, and you start to see a pattern."

    Psychiatrists still consider imaging technologies like M.R.I., for magnetic resonance imaging, and PET, for positron emission topography, to be crucial research tools.

    And the scanning technologies are invaluable as a way to detect physical problems like head trauma, seizure activity or tumors.

    Moreover, the experts point out, progress in psychiatry is by its nature painstakingly slow, and decades of groundwork typically precede any real advances.

    But there is a growing sense that brain scan research is still years away from providing psychiatry with anything like the kind of clear tests for mental illness that were hoped for.

    "I think that, with some notable exceptions, the community of scientists was excessively optimistic about how quickly imaging would have an impact on psychiatry," said Dr. Steven Hyman, a professor of neurobiology at Harvard and the former director of the National Institute of Mental Health.

    "In their enthusiasm, people forgot that the human brain is the most complex object in the history of human inquiry, and it's not at all easy to see what's going wrong."

    For one thing, brains are as variable as personalities.

    In a range of studies, researchers have found that people with schizophrenia suffer a progressive loss of their brain cells: a 20-year-old who develops the disorder, for example, might lose 5 percent to 10 percent of overall brain volume over the next decade, studies suggest.

    Ten percent is a lot, and losses of volume in the frontal lobes are associated with measurable impairment in schizophrenia, psychiatrists have found.

    But brain volume varies by at least 10 percent from person to person, so volume scans of patients by themselves cannot tell who is sick, the experts say.

    Studies using brain scans to measure levels of brain activity often suffer from the same problem: what looks like a "hot spot" of activity change in one person's brain may be a normal change in someone else's.

    "The differences observed are not in and of themselves outside the range of variation seen in the normal population," said Dr. Jeffrey Lieberman, chairman of the psychiatry department at Columbia University Medical Center and director of the New York State Psychiatric Institute.

    To make matters even more complicated, many findings are disputed. In people with severe depression, for instance, researchers have found apparent shrinkage of a part of the temporal lobe called the hippocampus, which is critical for memory.

    But other investigators have not been able to replicate this finding, and people with injuries to the hippocampus typically suffer amnesia, not depression, psychiatrists say.

    For problems like attention-deficit disorder and bipolar disorder, the experts say, psychiatrists have much less research on which to base their theories.

    Most fundamentally, imaging research has not answered the underlying question that the technology itself has raised: which comes first, the disease or the apparent difference in brain structure or function that is being observed?

    For a definitive answer, researchers would need to follow thousands of people from childhood through adulthood, taking brain scans regularly, and matching them with scans from peers who did not develop a disorder, experts say.

    Given the expense and difficulty, such a study may never be done, Dr. Hyman said.

    One investigator has used imaging research to fashion a small, experimental psychiatric treatment.

    In a series of studies of people with severe depression, Dr. Helen Mayberg, a professor of psychiatry at Emory University in Atlanta, found a baffling pattern of activity.

    Using PET scanning technology, Dr. Mayberg found sharp dips and spikes of activity in about a half-dozen areas of these patients' brains as their moods improved while they were taking either antidepressant drugs or placebos.

    The changes were similar in all patients, but it was difficult to tell how the scattering of the dips and spikes were related.

    By analyzing the peaks and valleys on the scans as part of a circuit - networked together, like a string of Christmas lights - Dr. Mayberg found that one spot in particular seemed to modulate the entire system, like a transformer or a dimmer.

    She confirmed the importance of this spot, called Brodmann area 25, by scanning the brains of mentally healthy people while they remembered painful episodes from their lives: while sad they, too, showed increased activity in this area.

    In March, Dr. Mayberg and a team based at the Rotman Research Institute in Toronto reported on six patients who had had electrodes implanted in their brains next to Brodmann area 25.

    All had been severely depressed for at least a year, and they had responded poorly to available therapies.

    The implanted electrodes, often used to treat Parkinson's disease, produce a current that slows neural activity, for reasons scientists do not yet understand.

    So far, the researchers reported in the journal Neuron, four of the six people have shown significant and lasting recovery; all four are still on antidepressant drugs but at reduced doses.

    And all four have returned to work or their usual routines, Dr. Mayberg said.

    The widely reported experiment has generated more than 300 requests from people to be considered for the operation, she added.

    "It's very important to understand that this is experimental, and the next step is to replicate what we did, with a placebo, and that could send us right back to the drawing board," Dr. Mayberg said in an interview.

    The findings so far are encouraging, she said, "but the idea that this is something for every severely depressed patient - well, shame on us if we suggest that.

    The brain is a very big place and we had better have a very good idea of what we're doing before holding this out as a treatment."

    Many people would rather not wait for the science of imaging to mature, however.

    At clinics in California, Washington, Illinois, Texas and elsewhere, doctors offer brain scans to people with a variety of conditions, from attention-deficit hyperactivity disorder, often called A.D.H.D., to depression and aggressive behavior.

    Dr. Daniel Amen, an adult and child psychiatrist based in Newport Beach, Calif., said he performed 28,000 scans on adults and children over the past 14 years, using a technique called Spect, or single photon emission computed tomography.

    In an interview, Dr. Amen said that it was unconscionable that the profession of psychiatry was not making more use of brain scans.

    "Here we are, giving five or six different medications to children without even looking at the organ we're changing," he said.

    He said the scans had helped him to distinguish between children with attention deficit problems who respond well to stimulants like Ritalin and those who do poorly on the drugs.

    In a series of books and medical articles, Dr. Amen argued that the images helped convince people that the behavior problems had a biological basis and needed treatment, with drugs or other therapies.

    "They increase compliance with treatment and decrease the shame and guilt" associated with the disorders, he said.

    At the Brainwaves Neuroimaging Clinic in Houston, doctors use the scans to diagnose and choose treatment for a range of psychiatric problems, according to a clinic spokeswoman.

    And a variety of doctors advertise the imaging services, particularly for attention-deficit disorder, on the Internet.

    But the experts who study imaging and psychiatry say there is no evidence that a brain scan, which can cost more than $1,000, adds significantly to standard individual psychiatric exams.

    "The thing for people to understand is that right now, the only thing imaging can tell you is whether you have a brain tumor," or some other neurological damage, said Paul Root Wolpe, a professor of psychiatry and sociology at the University of Pennsylvania's Center for Bioethics.

    He added, "This imaging technology is so far from prime time that to spend thousands of dollars on it doesn't make any sense."

    The big payoff from imaging technology, some experts say, may come as researchers combine the scans with other techniques, like genetic or biochemical tests.

    By radioactively marking specific receptors in the brain, for example, researchers are using brain scans to measure how brain chemicals known to affect mood, like dopamine, behave in people with schizophrenia, compared with mentally healthy peers.

    Imaging researchers are also studying depression-related circuits to see how they may arise from genetic variations known to put people at risk for depression.

    And as always, the technology itself is improving: a new generation of M.R.I. scanners, with double the resolution power of the current machines, is becoming more widely available, Dr. Lieberman said.

    "With increased resolution, we'll be able to do more sensitive and more precise work, and I would not be surprised if anatomy alone based on volume will be a diagnostic feature," he said.

    "We have gained an enormous amount knowledge from thousands of imaging studies, we are on the threshold of applying that knowledge, and now it's a matter of getting over the threshold."

    But for now, neither he nor anyone else can say when that will happen.

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Efforts to "see" depression bring to mind the early 20th–century experiments that established that the weight of the average human body decreased by 21 grams immediately following death.

Good idea for a movie title (and a superb film)

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even if it didn't turn out to be true.

But I digress.

Perhaps depression is like the soul: I don't know of a single person, religious or not, who believes that the soul has weight.

Rather, everyone considers it an intangible thing, like structure or order: it's a way of arranging things.

And, like structure or order, the soul isn't likely to make a balance beam quiver when it alights or disappears.

November 19, 2005 at 04:01 PM | Permalink | Comments (0) | TrackBack

World's most elegant kitchen scale

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It's the stainless steel Hanson Book Scale (above).

Stores on a shelf like a book when not in use.

Capacity: 2 kg/ 4 lb.4 oz.

Graduation: 1 g/ 1/8 oz.

Auto–Off LED display measures 42 x 16 mm.

Requires one CR2032 lithium battery (included).

£36.99 ($63.50; €54) here.

November 19, 2005 at 03:01 PM | Permalink | Comments (0) | TrackBack

It's what's for dinner — Specialty food industry goes online

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Over 2,400 members of the National Association for the Specialty Food Trade (NASFT) have buried the truffle

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and pulled their resources together into one comprehensive website.

Access to thousands of previously inaccessible/nearly unobtainable gourmet food products.

Especially useful for those in such places as Topeka, Kansas, who can't stop by the local Dean & DeLuca on the way home to pick up a few things for dinner.

Search by product, keyword or company right here.

November 19, 2005 at 02:01 PM | Permalink | Comments (0) | TrackBack

Moon Shoes Mini Trampolines

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From the website:

    Moon Shoes are trampolines made for feet so kids can jump with an anti–gravity effect.

    Made with high–density plastic and adjustable nylon straps.

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    Sure footing; non–skid soles.

    Fits up to size 9 men's shoe.

    For ages 7 (years) and over, up to 180 lbs.

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The purple ones pictured above are $37.95 here.

If you prefer black (below),

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they'll cost you $39.98 here.

November 19, 2005 at 01:01 PM | Permalink | Comments (1) | TrackBack

'If the brain is the theatre, consciousness is the play'

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Jay Ingram is an award–winning Canadian science journalist whose latest book (above) was called to my attention by Matt Penning last evening.

Ingram wrote an intriguing summary of his book which appeared yesterday on the website Quantum Biocommunication Technology; it follows.

    Raising The Curtain On Consciousness

    If the brain is the theatre, consciousness is the play.

    But who or what controls what we watch and how we watch it?

    Imagine what it would be like to live in a completely different world, an alien place in which you couldn’t even know your own mind, a place where, bombarded by sensory stimuli, your mind could extract only the merest hint of the total, and yet you somehow believed—or were made to believe—that you were all-seeing and all-knowing.

    Imagine further that this was a world where you were, in effect, an automaton, a self-deluded one at that, that walked and talked and acted at the behest of a whole set of mental modules whose operations you knew nothing about.

    Imagine that one of those modules, entirely of its own volition, routinely took the sparse data available to it and concocted bizarre stories to explain what was happening.

    Think of a world where an array of photons bombarding the retina becomes a three-dimensional space full of objects and textures, which can then be transformed to an internal image of the same scene, which later, when the brain is in a completely different chemical state, can be brought to mind once again, but this time in a wholly foreign setting.

    The strangest thing about this world is that seemingly magical transformations take place: ideas, visions, hallucinations and memories are created by electricity and chemistry, crossing the boundary between the physical and the immaterial in a manner that defies logic and science.

    The mystery is deepened by the fact that tinkering with the chemistry, the electrical circuitry or even the physical substrate of the brain can dramatically change those thoughts and images, without shedding any light at all on how they are created.

    Well, look no farther.

    This is exactly the world that you now inhabit.

    It is the world of the conscious mind, a world that is not at all what it seems.

    The science of consciousness has, in the last two decades, transformed our thinking about the brain and how it creates the world you experience.

    There are actually several Theatres of the Mind.

    One is the little theatre in your head that seems to be the place where the events in your conscious mind run, like a never-ending film. It is the home of your mind’s eye.

    It is a theatre with an audience of one: you.

    Only you can tell the rest of us what’s playing.

    It’s one thing for us to feel that way, but sometimes that inner theatre concept worms its way into people’s minds so thoroughly that even researchers seem to be envisioning it when they discuss consciousness.

    Philosopher Daniel Dennett has spent years skewering this idea of what he dismisses as the "Cartesian theatre."

    He argues that consciousness is not being processed, edited and presented to anyone/anything in the brain.

    There is no anyone/anything—consciousness is the end of the line.

    He’s been effective.

    Consciousness experts take pains to dissociate themselves from any notion of an inner theatre, but at the same time, one of the most popular theories of how consciousness works, called the "global workspace," is best viewed as—what else?—a theatre, with consciousness being played out on the stage.

    But it is being played for no one: it just is.

    Illuminating the theatre of the mind has become, in the last few years, one of the most challenging and exciting areas of science.

    That is what this book is about.

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Tell you what: Philip K. Dick (below)

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never died.

Rather, he's been reincarnated in the person of one Jay Ingram.

Ingram's book is available at Amazon Canada for $25.43 (Canadian).

[via Matt Penning]

November 19, 2005 at 12:01 PM | Permalink | Comments (0) | TrackBack

Slotless Knife Block

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Back on October 25 I remarked here on how the slots in knife blocks had somehow done a 90° turn while we weren't looking.

Now comes the Kapoosh™ (don't ask) Universal Knife Block (above and below) with no slots at all.

Bonus: you can put whatever utensils you like in it — not just knives.

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How about that cherry pitter? And the meat thermometer?

Holds up to 20 knives and/or utensils.

Bonus #2: You can remove the black polypropylene rods and their base and stick 'em in the dishwasher (below).

Bet you can't do that with your wooden knife block.

Or Martin Robitsch's version of one, employing the same principle of sticks insteads of slots.

Well, of course you could but the results wouldn't be something to write home about.

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$39.95 here.

November 19, 2005 at 11:01 AM | Permalink | Comments (2) | TrackBack

Grilling salmon on a cedar plank: 'A gimmick' that adds nothing (except burnt wood)

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I've mentioned before that I think Robert L. Wolke is one of the best food writers around.

He addresses topics head–on and brings to them a refreshing "no sacred cows" approach.

For example, in his Washington Post Food section column of November 9 debunking what he calls the myth of planking fish, especially salmon, to produce a unique and delicious flavor.

Here's his piece (from the newspaper — not of fish, booboo...).

    Believe What You Will, I Still Say Planking Is a Gimmick

    From a reader: I have read your column with great enthusiasm and interest over the last 10 years. I usually find it to be educational and helpful, and I had assumed well researched. Your planking story was a huge disappointment because you have many facts wrong and your research was lacking.

    Wolke: Oh, yeah? Well, I may be wrong, but so are you!

    My column has run for about eight years, not 10.

    Seriously, I do welcome comments of all sorts from my readers.

    Yours is not the only reproof I received following my skeptical column about cooking salmon on a cedar plank.

    I said the wood added little or no flavor beyond that of its smoke when it chars, and I questioned whether the early Northwest Indians really did cook on planks, lacking as they did steel saws and lumber mills.

    Here are some comments from readers who took me to task.

    • From the chairman of a university anthropology department: "Aboriginals . . . on the Northwest coast were making stone axes, mauls, adzes and wedges there by 4400 B.C. The mauls and wedges were used to split straight-grained cedar logs into planks, which they used for building houses and boats as well as (presumably) planking salmon. So while they didn't have lumber mills with band saws they were nevertheless able to make lots of cedar planks. Now I'll just have to try it [planking] myself."

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    • From a chef: "I attended a multi-day seminar at the Smithsonian on fish and seafood. A wonderful presentation was given by a Native American from the Pacific Northwest about the 3-day salmon festival that is still held in various places by different tribes.... As for the salmon, it is prepared the same way it has been for millennia: Make a big fire, butterfly the salmon and make a cedar slat frame that can be held in the ground, vertically around the fire.... The women... move the apparatus to the correct heat, where you can hold your palm up to the fire for 5 seconds. The searing holds the juices inside and the salmon, when done, literally bursts with juices and flavor when it is punctured.

    "You only steamed and smoked your fish. To do it correctly requires indirect heat (half of your grill). Cedar shingles work better and can be purchased at Home Depot ready to go (untreated bundle). Soak them, layer with sliced onions and lemon and top with dill, salt and pepper and put into a 450-degree or hotter grill. Roast at high temperature for 20 minutes or until done. If it has not created a crunchy crust, you cooked it at too low a temperature."

    Well, sorry, folks, but I still must wonder whether the good flavor of planked salmon, done either way, isn't due to the high-temperature searing, rather than to the infusion of any unique "cedar chemicals" into the fish.

    The following Q&A, I believe, reinforces my position.

    Q. When purchasing cedar some years ago to line a closet shelf, I found that regular cedar (such as you probably bought at Home Depot) is not the same as "aromatic cedar." I had to go to a specialty lumber store in the Washington, D.C., area to find the aromatic kind. I wonder if the early Northwest Indians had an even more aromatic type of cedar that they used to plank their fish?

    A. No, oddly enough it's the other way around; the Indians' wood was substantially less aromatic.

    The USDA Forest Service's Tree List catalogues nine species whose common names include the word "cedar," only a few of which belong to the true cedar genus Cedrus .

    The aromatic Eastern Redcedar, actually a juniper tree, Juniperus virginiana, has the property of repelling clothes moths and has long been used in cedar chests and closet linings. But it doesn't grow west of the Rockies.

    It is the Western Redcedar, Thuja plicata, also known as the Giant Arborvitae, native to the Pacific Northwest, that the Chinook and other Indian tribes used for dugout canoes, totem poles, woven bark clothing and, presumably, cooking planks.

    It does not have the pungent, moth-repelling scent at all.

    Maybe that's why young Native American women didn't have hope chests. (Or maybe not.)

    Thus, the "cedar" the Indians used wasn't the wood we may think it was, and they used it not as a flavoring agent but only as a way of propping the fish up at the right distance from a hot fire.

    The bottom line: Grilling or baking on a "cedar" plank is a gimmick.

    But if you insist on buying wooden boards from "gourmet" cookware suppliers at anywhere from 20 to 60 bucks a throw, your self-esteem will require that you taste "cedar's unique, spicy, citrus-y flavor" in whatever you cook on them.

    And you will hear tom-toms.

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Robert L. Wolke (www.robertwolke.com) is professor emeritus of chemistry at the University of Pittsburgh. His latest book is "What Einstein Told His Cook 2, the Sequel: Further Adventures in Kitchen Science" (W.W. Norton, 2005). He can be reached at wolke@pitt.edu.

November 19, 2005 at 10:01 AM | Permalink | Comments (6) | TrackBack

Jelly Watch

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$90 here.

November 19, 2005 at 09:01 AM | Permalink | Comments (0) | TrackBack

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