‘Smart’ ADHD drugs like Ritalin, Adderall may actually make students less productive

CAMBRIDGE, United Kingdom — So-called “smart” drugs, commonly used by students, might actually impair cognitive function, according to a new study. Researchers in the United Kingdom say drugs such as Ritalin, a common prescription medication for individuals with ADHD to enhance their concentration and cognitive performance, are often abused by students without the disorder.

In a series of four double-blind, randomized trials spaced a week apart, 40 healthy participants took either a placebo or one of three popular “smart” ADHD drugs. These included methylphenidate (sold as Ritalin), modafinil (Provigil), and dextroamphetamine (Adderall).

The team evaluated participants based on their performance in a test designed to simulate the complex decision-making and problem-solving tasks encountered in everyday life. They had to complete an exercise known as the Knapsack Optimization Problem, or “knapsack task.” In this task, the group received a virtual backpack and a selection of items with varying weights and values. They had to determine how to allocate the items in the backpack to maximize the total value of its contents.

Participants who took the ADHD drugs experienced small reductions in accuracy and efficiency, along with significant increases in time and effort, compared to their results when not on the drugs. While taking Ritalin, for example, participants took approximately 50 percent longer on average to complete the task than when they consumed a placebo.

High school student studying, taking exam in class
A team of researchers from the University of Oxford analyzed a group of more than 4,900 participants from England up to age 16 and looked at the results of their secondary education standardized examinations.
(© Monkey Business – stock.adobe.com)

“Our results suggest that these drugs don’t actually make you ‘smarter. Because of the dopamine the drugs induce, we expected to see increased motivation, and they do motivate one to try harder. However, we discovered that this exertion caused more erratic thinking — in ways that we could make precise because the knapsack task had been widely studied in computer science,” says Professor Peter Bossaerts, a professor of neuroeconomics at the University of Cambridge, in a media release. “Performance did not generally increase, so questions remain about how the drugs are affecting people’s minds and their decision making.”

Additionally, participants who performed well with the placebo often showed a more significant decline in performance and productivity after taking an ADHD drug. Those who ranked in the top 25 percent with a placebo frequently fell into the bottom 25 percent when under the influence of Ritalin.

Conversely, those who performed poorly with the placebo only occasionally showed minor improvements after taking a drug.

“Our research indicates that drugs anticipated to improve cognitive performance in patients may, in fact, cause healthy users to work harder while producing lower quality work over an extended period,” adds study author Dr. Elizabeth Bowman, a researcher at the Centre for Brain, Mind, and Markets at the University of Melbourne.

The study is published in the journal Science Advances.

You might also be interested in:

South West News Service writer Alice Clifford contributed to this report.

YouTube video


  1. So a double blind study was using a drug group that can cause/trigger a drug induced psychosis.What ethical board agreed to this study? I get drugs like psilocybin and ketamine are being tested on adults, these are on mature brains.

  2. The article wasn’t very well written. While mentioned very briefly, it should have been stressed that these were healthy adults NOT diagnosed with ADHD. That the study did NOT include patients suffering from ADHD to note any benefits and therefore the only conclusion is people who do not suffer from ADHD should not abuse the drugs. This article reads in such a manner that no one benefits from taking these drugs, which is far from the truth.

    1. Exactly.
      The article begins with the longevity benefits of drug treatment for those diagnosed with ADHD. Then the article confusingly and unclearly discusses a study of persons not diagnosed with ADHD.

Comments are closed.