Can Brain Scans See Depression? | ADHD Information
Intuitively, I know differences are there. Either current technology isn't sufficiently evolved to indicate the subtle ones in neuroology that make that difference; researchers aren't sufficiently skilled at patten matching (unlike someone like Fallen who is expert in recognizing patterns); or we don't understand neurophysiology (what functions map to what physical structures) sufficiently to understand what we're seeing on the scans. (And MRIs won't tell us much but fMRIs, MEG, and PET scans, should. From what I understand of them, anyway.) I sure hope this changes and soon because my own research plans (a few years away) count on being able to see and account for scan differences!
It doesn't really matter whether the chicken or egg came first. There is a correspondence between brain and behavioral patterns. Being able to clearly see them, though, is a different matter.
Can Brain Scans See Depression?
New York Times 18th October, 2005
By BENEDICT CAREY
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
,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.
http://www.nytimes.com/2005/10/18/h...agewanted=print
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I am more and more convinced that ADD and ADHD are not brain disorders, but are primitive reflex disorders. A primative reflex can control you and make you uncomfortable all your life until you mature it again.
Watch yourself and your ADHD children. Do they like to sit with their arms and legs bent at the same time? Do you? Are you more comfortable with your arms straight while your legs are bent? and visa versa?
If so, you might have a primitive reflex bothering you, giving you ADHD symptoms.
Did you know that you can mature the STNR reflex and get rid of those symptoms you have had all your life, if they are caused by this primitive reflex?
I thought that you all would want to know and find out for yourselves.
the book is called Stopping ADHD and it is written by two PhD doctors of education from Indianapolis.
Can a brain scan make you depressed???
[QUOTE=Miss Frizzle]OMG!
Davido looks like a brain scan![/QUOTE]
OMG!...Missy looks like David'0!!!
The problem is that the brain is not a computer. It would be great - because you could roll out a schematic and say "look - there's your problem". It's a very complicated organ - and it stores information in a three-dimensional grid. We're just beginning to understand what each cell can do - it will be a while before we can map it and say definitively where exactly a problem is.
PET Scans are getting way more accurate. When they started - you could see a cloud of a type of chemical on the brain - you knew it's at the front, the back top or bottom but that was the extent.
Now, PET scans can target down to a couple of centimeters. We need to get better focus and they are working on that. Eventually, you'll sip a little tag material for a specific chemical in the brain - and they'll be able to follow it right to a few cells. It boggles MY mind!
I don't worry that it's not easily seen now. When you live it - quantatative proof like that is for the naysayers - not me.
Glen, how much do you know about the differences between PET, fMRI, and MEG scanning? I know a little but not even by 1/4.
Despite your protests, you're far more of a quantitative kind of guy than I am a girl. But I am sure in my own mind that even the spiritual stuff has a physiological correlate of some kind.
I'd say "that's the way God created it" but know you don't believe in God, so substitute universe in there or whatever construct works for you as the source of how the universe functions. Actually, the incredible complexity of the brain is one of the things that underlies my belief in some form or force beyond man, because I can't see man devising anything even close. As you said, a computer is a far, far cry. Nor can I envision a kind of intelligence that could create something like a brain.
But that's also neither here nor there. I'm actually just asking what you may know about these various technologies, not debating theology.
I know a lot about all the techs - don't worry that you don't most people don't.
PET - positron emission tomography. They use a mildly radioactive "tag" chemical that bonds to a specific chemical in the body. The body moves it to where the chemical is and it emits a mild radioactivity that's detected. That's why it's always looking like a weather picture - very cloudy. Not accurate where you can say "there's one cell we should look at". they are improving.
MRI is magnetic Resonance imaging. It's kind of like a microwave oven. They bombard all your cells with magnetic fields - strong ones. That's why you go in with the caution of taking all metal off you. The fields shake your cells and they emit a pulse that the sensor picks up. It's very sensitive and that's why they look so good.
CAT is Computer Assisted Tomography - it's just a three-dimensional X-Ray. They are so sensitive now they can see your skin in full view under your clothing, and move it layer by layer. Very cool!
MEG - not familiar with but I'll find out for you!!
I prefer to put things as "It is as it is". Things aren't inherently good, bad or whatever. It just "is". I tend not to dwell when I can help it.
OMG!
Davido looks like a brain scan!
Topic: Can Brain Scans See Depression?
No, but I can. When I look in the mirror...