AD/HD-medicatie als stimulant bij studie-inspanningen?

Ritalin, dexamfetamine en de rest van de ‘speed’ gerelateerde ‘geneesmiddelen’ bevorderen het studeerproces
niet. Integendeel.

Hard-working, but
incompetent
Study drugs can make people worse at problem-solving, not
better
FOR MORE than six months Americans have been struggling to get their
hands on medications like dextroamphetamine (better known as Adderall)
and methylphenidate (Ritalin). Officially, these stimulant drugs are used to
treat attentiondeficit hyperactivity disorder (ADHD).
Unofficially, the drugs are also popular with devotees of “nootropics”
—chemicals that supposedly boost brainpower. Students and workers in
industries from tech to finance take the medications in the hope they will
improve their concentration and ability to get things done. But a new paper
suggests that this may be illadvised. The drugs seem to make people
slightly worse at solving problems, not better.
In the paper, published on June 14th in Science Advances, a group of
researchers led by Peter Bossaerts, an economist at the University of
Cambridge, tested how Adderall, Ritalin and another stimulant drug called
modafinil (Provigil) affected 40 healthy people’s ability to perform
optimisation problems. They used the “knapsack task”, in which
participants had to work out which items to put into a bag. The idea was to
maximise the value of the items without exceeding the carrying weight of
the sack. The researchers used several trials of varying difficulty, each with
different weight limits and lists of items. The participants visited the lab on

four separate days. On each day they were given either a placebo pill or one
of the drugs under study. The study was doubleblind, meaning neither the
participants taking the pills nor the experimenters handing them out knew
which had been administered on which day. They found that participants
achieved slightly worse endresults on the task after taking a drug. The
drugs did not impair people’s ability to find an optimal solution.
Participants managed this in around half of the trials, whether they took
the drugs or the placebo pills. But they did cause a small drop in the value
of participants’ knapsacks across all trials, by making the nonoptimal
solutions worse.
Perhaps more striking was how drugs changed the way people attacked the
task. After taking Adderall or Ritalin (but not Provigil) the participants
spent far longer working on their knapsacks than they did when they had
taken the placebo pill. (Participants were given four minutes to complete
each trial but could submit an answer earlier if they thought they had found
a good solution). When given Ritalin in particular, subjects were around
50% slower at completing trials. That was roughly equivalent to the delay
expected from going from the easiest to the most difficult trial in the
placebo session.
This extra time was spent moving items in and out of the knapsack,
somewhat erratically. The authors assessed the productivity of each move
by measuring how much it increased the value of a sack, and found that
participants were about 9% less productive when they had taken one of the
study drugs compared with a placebo pill. “It was like they were trying to
solve a jigsaw puzzle by randomly throwing pieces in the air,” says Dr
Bossaerts.
The authors argue that although the drugs made people more motivated
and helped them put more effort into the task, this was more than
cancelled out by the fact that the drugs decreased the quality of all that
effort. In other words, although people tried harder, they became far less
competent. Just how much the drugs hindered performance seemed to
depend on how good a participant was without them. Star performers
during the placebo session fell to the bottom of the pack when they had
taken the drugs.
Popping stimulants is commonplace in industries like software and finance.
One survey of 6,500 American college students reported that 14% had used
the drugs for nonmedical reasons. This latest study adds to a growing pile
of evidence suggesting that such drugs do little to improve cognitive
performance in people who do not need them. For tech bosses looking for
efficient employees, and workers hoping to clock off at a reasonable hour,
the stimulant shortage may be a good thing.