On The Validity of Brain Scans as Proofs of Psychiatric
by Dean Blehert
Dr. Grace Jackson, a psychiatrist and an expert on brain
imaging, refutes the validity of the attempts by various psychiatrists
to defend the "science" of their diagnoses by using
comparative brain scans. Her article, which, I've linked below
my own write-up, along with her references, is technical enough
to leave many readers in the dark, so I've tried to put her
main points into simple, non-technical language first, then
link the article for those who want all the technical details.
This way the data may be more usefully forwarded to others.
Dr. Jackson doesn't go into the most basic lies in psychiatry's
science, but since many may be impressed when a psychiatrist
on TV holds up brain scans, it's useful to know a bit about
the science and NON-science behind these scans. Here's my
understanding of Dr. Jackson's points:
Psychiatrists are attempting to refute the assertion that
there's no real science behind psychiatry. The chief criticism
is that psychiatry defines sets of symptoms as diseases caused
by chemical imbalances in the brain (especially, lacks of
certain neuro-transmitter chemicals) -- and does so with no
evidence that any such chemical imbalances exist. Psychiatrists
reply by holding up photos of brain scans. One photo will
be (allegedly) a scan of the brain of someone with a psychiatric
"illness", for example, ADHD; the other scan will
be that of someone (allegedly) normal. The psychiatrists say,
look at the pattern of neural activity in the "ADHD"
brain, and note how it's not like the pattern of activity
in the "normal" brain. When the ADHD person is given
an anti-ADHD drug (like Ritalin), then it looks like the normal
brain. And that's been the basis for psychiatric classification
of illnesses, all very scientific.
[Note: Of course, the last sentence above is simply a lie:
The illnesses were created by vote long before the brain scans
were developed to justify the vote.]
This use of brain scans to prove the existence of mental
illness is bogus for several reasons:
1. The people who show these brain scans to the press don't
differentiate between the two broad categories of brain scans,
Anatomical and Functional. The anatomical scans are reliable,
well-established techniques, in use for over 50 years. The
functional scans are still relatively controversial research
The anatomical scans give us a view of the brain, not in
action, but static. They don't show activity well. They do
show tumors, brain damage and other relatively unchanging
phenomena. They don't show things like firing of nerves or
flow of blood. No one has yet been able to use Anatomical
scans to demonstrate any correlation between the various mental
illnesses named by psychiatrists and the phenomena (tumors,
damaged tissue, etc.) that show up in Anatomical scans. So
the most reliable scans do NOT demonstrate the validity of
psychiatry, do NOT show correlation between the brain phenomena
they reveal and psychiatric illness.
2. The Functional scans attempt to show us brain ACTIVITY
when the person is at rest or engaged in some specific activity.
The recent assertions of psychiatrists (in defending psychiatry)
have been that the functional scans show the brain's activity
(its nerves firing, etc.). Actually, the functional scans
show the flow of blood within the brain. This flow of blood
does NOT necessarily indicate an area of nerve activity. That
is, a functional scan that shows activity on, say, the right
side of the brain does not show "brain" activity
on the right side of the brain, where, by "brain"
activity, is meant the firing of neurons, the transmission
of impulses from neuron to neuron via neuro-transmitter chemicals,
etc. It shows a flow of blood to that part of the brain. Various
studies have shown that the flow of blood to a part of the
brain does not necessarily correlate with neuro-activity in
that part of the brain. In fact, some studies suggest that
the blood flows to INactive parts of the brain to get them
more active. Other studies suggest that signs of activity
in one part of the brain are actually caused by nerve activity
in another part of the brain.
There are all sorts of variables involved, and the research
on this area is far from conclusive. When a scan shows increase
in circulation to a part of the brain, we don't know what
it shows in terms of "brain activity."
3. Claimed comparisons of functional scans of so-called diseased
brains to those of so-called normal brains have all been invalid,
since they failed to take into consideration the various factors
that influence brain circulation, including age, diet, gender,
medical condition, weight, height, whether on drugs, drug
history, education, etc. All of these and other factors influence
the way a brain looks on a functional brain scan. (In one
notorious study, the supposed differences between the normal
and abnormal brains were entirely explained when it was learned
that one of the groups was significantly older than the other.
In another study, the people with alleged psychiatric illnesses
showed brain abnormalities that were entirely explained when
it was discovered that they were all on psychiatric drugs,
and that the drugs were known to cause such abnormalities.)
4. The idea that a functional scan gives an instant view
of brain activity is false. The sorts of brain activity we're
interested in (neuro-activity) is instant, happening in thousandths
of a second. A functional scan shows shifts in circulation,
which, even where thought to be associated with brain activity,
lag behind that activity by a few seconds (a few seconds being
hundreds of times longer than the brain activity itself).
In other words, this is a very crude view of the brain in
action (if it is a view of brain activity, which is doubtful,
since the relationship of shifts in blood circulation to brain
activity are still not well understood).
5. The psychiatrists presenting these images to the public
imply that we are looking at images of two brains, one normal,
the other diseased. In fact, each image is a statistical average
of many images. No one individual has either of these scans,
and the averaging suggests clearer and more consistent differences
that would not show up in individual scans. Individual scans
(even assuming all the earlier points were handled) have far
too much variability to be reliable for diagnosis. Where imaging
studies compare groups of "normal" and "abnormal"
brains, there is a large overlap between the groups. Many
people alleged to be ADHD, for example, do not show the brain
patterns claimed to be characteristic of ADHD.
6. Assertions that image comparisons show that certain locations
of the brain are the sources of various conditions are not
scientific assertions, and make a number of invalid assumptions.
7. If these imaging techniques are to be used to make valid
diagnoses (they can't, really see above), then other
problems come up: The imaging techniques themselves are possibly
dangerous dangers yet unknown, but they do disturb
Three other points not covered in the article referenced:
1. Such image comparisons depend on someone deciding that
a person is normal or is ADHD (or schizophrenic or whatever).
Who makes this decision and on what basis? Presumably one
or more psychiatrists labels someone ADHD. Yet the criteria
for this are vague enough and broad enough that they could
be made to fit anyone. When a psychiatrist holds up two brain
scans and says that scan A is that of an ADHD brain and scan
B is that of a normal brain, who has decided (prior to the
brain scans being made) that the first person is ADHD and
the second is normal? Does psychiatry even have a definition
of "normal"? How does one verify either of these
It is known (from various studies) that psychiatrists differ
greatly in their diagnosis of individuals; that for any person
on trial who claims insanity, psychiatrists can be found both
to defend and attack that claim; that psychiatrists have often
released people from institutions as "cured" or
"no longer dangerous", who have then murdered; that
psychiatrists, given people to diagnose who included students
hired as experimental subjects or newspaper reporters or others
who, to non-psychiatric eyes, appeared normal, have mis-diagnosed
them as insane and ordered them committed.
All we know is that two images we are shown look different.
The validity of calling one image normal, the other diseased,
depends on how much we are willing to rely on psychiatric
classification in the first place. In other words, it assumes
what psychiatrists claim to be proving with the images. To
prove something by first assuming the validity of what you
are trying to prove invalidates your proof. In other words,
if, in order to prove that all dogs are purple, I have to
assume that all dogs are purple, I have no valid proof. Those
who find psychiatry to be bad science show that the psychiatric
label, ADHD, is based on no science, and is described so broadly
that it is possible to apply the label to anyone. Psychiatrists
then show that slides of the brains of "ADHD" people
differ from slides of "normal" people. So psychiatrists
are assuming what is to be proven: that they can validly label
some people as ADHD.
2. Even if it were true that some known pattern of brain
activity corresponded to some known uncomfortable mental state,
that wouldn't prove that the brain activity caused the mental
state or that the mental state should be handled by medicating
the brain. Here's an example: Let's say that brain scans of
sad (depressed) people show less activity in a certain part
of the brain. So you medicate the guy and the activity in
that part of the brain increases, and also, he feels less
depressed. What's wrong with this? A bit more investigation
shows that the guy got sad when his girlfriend left him. We
look at guys who've been dumped by their girlfriends, and
find that they usually get depressed, and their brains get
this same pattern. Now, which is the cause that is most likely
to respond to treatment? Helping the guys get over being dumped,
helping them to handle the factors in their lives that make
it hard for them to find stable girlfriends, etc., or drugging
them to make their brains "normal"?
More investigation will probably show the following:
A. The drug solution is forever. After a while, the drug
ceases to boost brain activity, so more of the drug is needed,
and eventually other drugs are needed. If the person goes
off the drug, his brain is no longer as capable of that activity.
(Usually the body loses the ability to do what a drug has
done for it.) So the activity in that part of the brain is
lower than it was to start with if he withdraws. And if he
stays on the drug and additional drugs to handle the eventual
failure of the first drug, he develops all sorts of health
problems (liver toxicity, etc.). All this in addition to the
various "side effects" of the drugs.
B. Because he simply suppresses the sadness, he never does
handle the reasons why his girlfriend dumped him (or he lost
his job or whatever precipitated the depression). He's running
away from life, not facing it, and, worse, losing the ability
to face it.
The point is that showing a correlation between brain function
and mental state is necessary, but not sufficient to show,
scientifically, that the brain function is the cause of the
mental state. Cause here means source -- or, if that's too
metaphysical, it means that which, when handled, eliminates
the difficulty. Liposuction gets rid of fat, just as drugs
claim to get rid of supposedly bad brain patterns, but no
one claims that liposuction handles the cause of being obese,
nor is there evidence (that I know of) that indicates it improves
health -- on the contrary.
C. Any alleged science that is developed after the fact
to prove what has earlier been asserted without proof must
be doubted. Psychiatrists asserted that hundreds of conditions
were illnesses caused by chemical imbalances of the brain
long before these brain-imaging techniques were used to attempt
to justify those assertions. This is lousy science from the
start, because the scientists are trying to justify old assertions,
not to find out what is, in fact, the case. A good scientist
tries to DISprove his hypothesis, not to prove it.
Curious Consensus: "Brain Scans Prove Disease"?
By Grace E. Jackson, MD
Right click here to download a copy of the article as PDF