Wall St. Journal, October 1, 2004
Memory drugs create new ethical minefield
by Sharon Begley, Wall St. Journal
Move over, botox. Although injections of the most potent natural toxin
known to science are marketed as knife-free plastic surgery to reduce
wrinkles, Botox treatment is actually a neurological intervention. The
toxin blocks the release of a neurochemical, acetylcholine, from neurons.
That makes it the opening act in what promises -- or threatens -- to be
a significant new drama. Welcome to "cosmetic neurology."
Sure, there have been reports over the years of, shall we say, recreational
use of prescription pharmaceuticals. Some musicians and nervous public
speakers take beta blockers (a heart drug) to vanquish stage fright. Modafinil
(aka Provigil) is a stimulant approved for narcolepsy,
but it has an underground following among those who want to feel as alert
and rested after five hours of sleep as after eight.
Ritalin, for attention-deficit hyperactivity disorder, improves concentration
and the ability to plan, making it popular among healthy adults who simply
want an edge in multitasking.
A string of recent discoveries, many of them from small studies that
have flown under the radar, suggest that this is only the beginning. Ritalin,
for instance, specifically boosts spatial working memory, or the ability
to remember layouts and locations. Just the thing for back-country hikers,
perhaps, or architects mentally juggling blueprints?
Compounds called cholinesterase inhibitors boost levels of the neurotransmitter
acetylcholine, which lets neurons communicate with each other. One, donepezil
(sold as Aricept), is approved for Alzheimer's disease. But that may be
only one of its talents. In a 2002 study, scientists gave donepezil to
one group of healthy, middle-age pilots and dummy pills to another. The
donepezil group did markedly better learning maneuvers in a Cessna 172
simulator, particularly those used in flight emergencies.
Some drugs that affect memory work very selectively. So-called CREB
inhibitors (CREB is a protein essential for incising memories in the brain)
"seem to selectively erase only disturbing memories," says neurologist
Anjan Chatterjee of the University of Pennsylvania, Philadelphia. And
propanolol, a beta blocker, enhances the memory of events that are emotionally
charged and that the brain otherwise suppresses. It also seems to erase
the negative emotions associated with bad memories. Healthy people given
the drug recall disturbing stories as if they were no more emotionally
charged than a grocery list.
It's not that neuroscientists are deliberately looking for drugs that
might be used for cosmetic neurology. Rather, these more frivolous uses
are being discovered serendipitously, often in research on serious neurological
diseases such as stroke. For instance, scientists find that small doses
of amphetamines help stroke patients undergoing physical therapy relearn
motor skills, such as tying shoes and using utensils, better and more
quickly than with therapy alone. Taken half an hour before a therapy session,
amphetamines seem to promote what's called neuroplasticity, the ability
of the brain to form new connections or strengthen existing ones between
its neurons. Those connections underlie both simple and complex sequences
of movement.
"With amphetamines, the effects of therapy are more pronounced,"
says Dr. Chatterjee. "And animal studies suggest that pairing amphetamines
with motor training leads to greater brain plasticity."
The day may be coming when perfectly healthy people will pop speed before
a tennis lesson or piano instruction, knowing it may stimulate the brain
rewiring that underlies a perfect backhand or a flawless "Fur Elise."
Botox, after all, originally received government approval to treat two
serious eye-muscle disorders, and now aging boomers regard a quick fix
as no more momentous than a swipe of mascara. Cosmetic neurology could
well follow the same arc, which means that the time for neurologists to
weigh in on the ethical implications of all this is now.
Those implications are profound. If drugs can improve learning, make
painful memories fade and sharpen attention, should physicians prescribe
them? Must physicians prescribe them? Must patients -- perhaps pilots
compelled by an employer -- take them? Might one airline distinguish itself
from competitors by advertising its donepezil-taking crews?
Dr. Chatterjee captures the dilemma in a paper he wrote for the current
issue of Neurology: "The distinction between therapy and enhancement
can be vague, particularly when the notion of 'disease' lacks clear boundaries.
... If one purpose of medicine is to improve the quality of life of individuals
who happen to be sick, then should medical knowledge be applied to those
who happen to be healthy," lifting patients from normal functioning
to enhanced functioning?
We can wring our hands all we want about pills that make learning more
effective without greater effort, offending the belief that gains should
be hard-earned, or about drugs that selectively erase painful memories,
evoking a Brave New World of the happily drugged -- and less-than-fully
human. I have a feeling it won't make much difference.
"Patient" has become synonymous with "consumer,"
someone unlikely to take kindly to physicians, let alone ethicists, blocking
his or her pursuit of self-improvement and happiness.
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