راه حلی طبیعی برای درمان ADHD
]پژوهشکده علوم شناختی – نیویورک تایمز[پاداشهایی
همچون جفتیابی، پول، مواد مخدّر و وضعیتهای جدید همگی به ترشح دوپامین
در مدار پاداشدهی در مغز (ناحیهای که در زیر کورتکس در اعماق مغز قرار
دارد) منجر میگردد. دوپامین در کنار برانگیختن حس رضایت در فرد به مغز وی
نیز سیگنال میفرستد که «توجه کن! این تجربه آن قدر مهم است که باید آن را
به یاد بیاوری». در بیماری ADHD فرد دچارِ کاهش گیرندههای دوپامین میگردد.
دکتر نورا والکو (Nora D. Volkow)٬ دانشمندی که موسسه ملی سوء مصرف مواد (National Institute on Drug Abuse) را اداره میکند مسیرهای پاداش دوپامین را در افراد مبتلا به ADHD مورد مطالعه قرار داده است. وی و همکارانش با استفاده از دستگاه تصویربرداری PET تعداد گیرندههای دوپامینی مغز آن دسته از بزرگسالانی را که مبتلا به ADHD بودند، اما دارو مصرف نمیکردند با گروه کنترل سالم مقایسه کردند. نتیجه این بود که مبتلایان به ADHD نسبت به گروه کنترل تعداد گیرندههای D2 و D3 بسیار کمتری در مدارهای پاداش خود دارند. D2 و D3 دو
نوع گیرندة مربوط به دوپامین میباشند. افزون بر این هر چه سطح گیرندههای
دوپامین کمتر باشد نشانگان کاهش توجه در فرد مورد مطالعه نیز بیشتر خواهد
بود. مطالعات دیگر نیز کمبود گیرندهها را در این بیماران تایید کرده است.
نویسنده مقاله در گزارش خود پیشنهاد میدهد که شاید راه حل طبیعی برای درمان این
بیماری علاوه بر درمانهای دارویی این باشد که از راهکارهای محیطی استفاده
کنیم. به عنوان مثال در انتخاب مدارس و انتخاب شغل برای این افراد٬
کنجکاوی و توجه متغیر آنها را لحاظ کنیم و آن را به مسیر درستی هدایت کنیم.
مدارسی با کلاسهای
کوچک با تکالیف مهارت - محور و نیز تکالیف کامپیوتری تابعِ سرعت
دانشآموز میتواند انتخاب بهتری باشد. برای مطالعه کامل مقاله به لینک زیر
A Natural Fix for A.D.H.D.
Richard A. Friedman is a professor of clinical psychiatry and the director of the psychopharmacology clinic at the Weill Cornell Medical College.
deficit hyperactivity disorder is now the most prevalent psychiatric
illness of young people in America, affecting 11 percent of them at some
point between the ages of 4 and 17. The rates of both diagnosis and
treatment have increased so much in the past decade that you may wonder
whether something that affects so many people can really be a disease.
for a good reason. Recent neuroscience research shows that people with
A.D.H.D. are actually hard-wired for novelty-seeking — a trait that had,
until relatively recently, a distinct evolutionary advantage. Compared
with the rest of us, they have sluggish and underfed brain reward
circuits, so much of everyday life feels routine and understimulating.
compensate, they are drawn to new and exciting experiences and get
famously impatient and restless with the regimented structure that
characterizes our modern world. In short, people with A.D.H.D. may not
have a disease, so much as a set of behavioral traits that don’t match
the expectations of our contemporary culture.
the standpoint of teachers, parents and the world at large, the problem
with people with A.D.H.D. looks like a lack of focus and attention and
impulsive behavior. But if you have the “illness,” the real problem is
that, to your brain, the world that you live in essentially feels not
of my patients, a young woman in her early 20s, is prototypical. “I’ve
been on Adderall for years to help me focus,” she told me at our first
meeting. Before taking Adderall, she found sitting in lectures
unendurable and would lose her concentration within minutes. Like many
people with A.D.H.D., she hankered for exciting and varied experiences
and also resorted to alcohol to relieve boredom. But when something was
new and stimulating, she had laserlike focus. I knew that she loved
painting and asked her how long she could maintain her interest in her
art. “No problem. I can paint for hours at a stretch.”
like sex, money, drugs and novel situations all cause the release of
dopamine in the reward circuit of the brain, a region buried deep
beneath the cortex. Aside from generating a sense of pleasure, this
dopamine signal tells your brain something like, “Pay attention, this is
an important experience that is worth remembering.”
more novel and unpredictable the experience, the greater the activity
in your reward center. But what is stimulating to one person may be dull
— or even unbearably exciting — to another. There is great variability
in the sensitivity of this reward circuit.
have long known this to be the case, and everyday experience bears it
out. Think of the adrenaline junkies who bungee jump without breaking a
sweat and contrast them with the anxious spectators for whom the act
evokes nothing but terror and dread.
Nora D. Volkow, a scientist who directs the National Institute on Drug
Abuse, has studied the dopamine reward pathway in people with A.D.H.D.
Using a PET scan, she and her colleagues compared the number of dopamine
receptors in this brain region in a group of unmedicated adults with
A.D.H.D. with a group of healthy controls. What she found was striking.
The adults with A.D.H.D. had significantly fewer D2 and D3 receptors
(two specific subtypes of dopamine receptors) in their reward circuits
than did healthy controls. Furthermore, the lower the level of dopamine
receptors was, the greater the subjects’ symptoms of inattention.
Studies in children showed similar changes in dopamine function as well.
findings suggest that people with A.D.H.D are walking around with
reward circuits that are less sensitive at baseline than those of the
rest of us. Having a sluggish reward circuit makes normally interesting
activities seem dull and would explain, in part, why people with
A.D.H.D. find repetitive and routine tasks unrewarding and even
like Adderall and Ritalin help by blocking the transport of dopamine
back into neurons, thus increasing its level in the brain.
patient of mine, a 28-year-old man, was having a lot of trouble at his
desk job in an advertising firm. Having to sit at a desk for long hours
and focus his attention on one task was nearly impossible. He would
multitask, listening to music and texting, while “working” to prevent
activities from becoming routine.
he quit his job and threw himself into a start-up company, which has
him on the road in constantly changing environments. He is much happier
and — little surprise — has lost his symptoms of A.D.H.D.
patient “treated” his A.D.H.D simply by changing the conditions of his
work environment from one that was highly routine to one that was varied
and unpredictable. All of a sudden, his greatest liabilities — his
impatience, short attention span and restlessness — became assets. And
this, I think, gets to the heart of what is happening in A.D.H.D.
that humans evolved over millions of years as nomadic hunter-gatherers.
It was not until we invented agriculture, about 10,000 years ago, that
we settled down and started living more sedentary — and boring — lives.
As hunters, we had to adapt to an ever-changing environment where the
dangers were as unpredictable as our next meal. In such a context,
having a rapidly shifting but intense attention span and a taste for
novelty would have proved highly advantageous in locating and securing
rewards — like a mate and a nice chunk of mastodon. In short, having the
profile of what we now call A.D.H.D. would have made you a Paleolithic
fact, there is modern evidence to support this hypothesis. There is a
tribe in Kenya called the Ariaal, who were traditionally nomadic animal
herders. More recently, a subgroup split off and settled in one
location, where they practice agriculture. Dan T. A. Eisenberg, an
anthropologist at the University of Washington, examined the frequency
of a genetic variant of the dopamine type-four receptor called DRD4 7R
in the nomadic and settler groups of the Ariaal. This genetic variant
makes the dopamine receptor less responsive than normal and is
specifically linked with A.D.H.D. Dr. Eisenberg discovered that the
nomadic men who had the DRD4 7R variant were better nourished than the
nomadic men who lacked it. Strikingly, the reverse was true for the
Ariaal who had settled: Those with this genetic variant were
significantly more underweight than those without it.
if you are nomadic, having a gene that promotes A.D.H.D.-like behavior
is clearly advantageous (you are better nourished), but the same trait
is a disadvantage if you live in a settled context. It’s not hard to see
why. Nomadic Ariaal, with short attention spans and novelty-seeking
tendencies, are probably going to have an easier time making the most of
a dynamic environment, including getting more to eat. But this same
brief attention span would not be very useful among the settled, who
have to focus on activities that call for sustained focus, like going to
school, growing crops and selling goods.
may wonder what accounts for the recent explosive increase in the rates
of A.D.H.D. diagnosis and its treatment through medication. The
lifetime prevalence in children has increased to 11 percent in 2011 from
7.8 percent in 2003 — a whopping 41 percent increase — according to the
Centers for Disease Control and Prevention. And 6.1 percent of young
people were taking some A.D.H.D. medication in 2011, a 28 percent
increase since 2007. Most alarmingly, more than 10,000 toddlers at ages 2
and 3 were found to be taking these drugs, far outside any established
of the rising prevalence of A.D.H.D. is doubtless driven by the
pharmaceutical industry, whose profitable drugs are the mainstay of
treatment. Others blame burdensome levels of homework, but the data show
otherwise. Studies consistently show that the number of hours of
homework for high school students has remained steady for the past 30
think another social factor that, in part, may be driving the
“epidemic” of A.D.H.D. has gone unnoticed: the increasingly stark
contrast between the regimented and demanding school environment and the
highly stimulating digital world, where young people spend their time
outside school. Digital life, with its vivid gaming and exciting social
media, is a world of immediate gratification where practically any
desire or fantasy can be realized in the blink of an eye. By comparison,
school would seem even duller to a novelty-seeking kid living in the
early 21st century than in previous decades, and the comparatively
boring school environment might accentuate students’ inattentive
behavior, making their teachers more likely to see it and driving up the
number of diagnoses.
all the news is so bad. Curiously, the prevalence of adult A.D.H.D. is
only 3 to 5 percent, a fraction of what it is in young people. This
suggests that a substantial number of people simply “grow out” of it.
How does that happen?
one explanation is that adults have far more freedom to choose the
environment in which they live and the kind of work they do so that it
better matches their cognitive style and reward preferences. If you were
a restless kid who couldn’t sit still in school, you might choose to be
an entrepreneur or carpenter, but you would be unlikely to become an
accountant. But what is happening at the level of the brain that may
explain this spontaneous “recovery”?
try to answer that question, Aaron T. Mattfeld, a neuroscientist at the
Massachusetts Institute of Technology, now at Florida International
University in Miami, compared the brain function with resting-state
M.R.I.s of three groups of adults: those whose childhood A.D.H.D
persisted into adulthood; those whose had remitted; and a control group
who never had a diagnosis of it. Normally, when someone is unfocused and
at rest, there is synchrony of activity in brain regions known as the
default mode network, which is typically more active during rest than
during performance of a task. (In contrast, these brain regions in
people with A.D.H.D. appear functionally disconnected from each other.)
Dr. Mattfeld found that adults who had had A.D.H.D as children but no
longer had it as adults had a restoration of the normal synchrony
pattern, so their brains looked just like those of people who had never
don’t yet know whether these brain changes preceded or followed the
behavioral improvement, so the exact mechanism of adult recovery is
But in another measure of brain synchrony, the adults who had recovered looked more like adults with A.D.H.D., the M.I.T. study found.
people without it, when the default mode network is active, another
network, called the task-positive network, is inhibited. When the brain
is focusing, the task-positive network takes over and quiets the default
mode network. This reciprocal relationship is necessary in order to
groups of adult A.D.H.D. patients, including those who had recovered,
displayed simultaneous activation of both networks, as if the two
regions were out of step, working at cross-purposes. Thus, adults who
lost most of their symptoms did not have entirely normal brain activity.
are the implications of this new research for how we think about and
treat kids with A.D.H.D.? Of course, I am not suggesting that we take
our kids out of school and head for the savanna. Nor am I saying we that
should not use stimulant medications like Adderall and Ritalin, which
are safe and effective and very helpful to many kids with A.D.H.D.
perhaps we can leverage the experience of adults who grew out of their
symptoms to help these kids. First, we should do everything we can to
help young people with A.D.H.D. select situations — whether schools now
or professions later on — that are a better fit for their
novelty-seeking behavior, just the way adults seem to self-select jobs
in which they are more likely to succeed.
school, these curious, experience-seeking kids would most likely do
better in small classes that emphasize hands-on-learning, self-paced
computer assignments and tasks that build specific skills.
will not eliminate the need for many kids with A.D.H.D. to take
psychostimulants. But let’s not rush to medicalize their curiosity,
energy and novelty-seeking; in the right environment, these traits are
not a disability, and can be a real asset.
Correction: November 16, 2014
earlier version of this essay omitted an attribution for part of the
description of an M.I.T. study comparing patterns of brain activity in
adults who recovered from childhood A.D.H.D. and adults who did not. The
description of one finding — about the similarity of the two groups on
one measure of brain synchrony — came from a news release from the
McGovern Institute for Brain Research at M.I.T.