Certain drugs can decrease productivity in people without ADHD, study shows

New research from university academics shows workers and students taking ‘smart’ drugs could be inhibiting their performance and productivity.

In collaboration with one another the University of Cambridge and the University of Melbourne have found cognitive enhancers, otherwise known as ‘smart’ drugs, such as methlphenidate, sold under the brand name Ritalin, are commonly prescribed for attention deficit hyperactivity disorder (ADHD), but are also taken by those without a diagnosis, in the belief that the drugs will enhance focus and cognitive performance.

To conduct the study experts set out four double-blinded, randomised trials in Melbourne, each a week apart and gave 40 participants the option of taking one of the three popular ‘smart drugs – methylphenidate, modafinil or dextroamphetamine – or a placebo.

They were assessed on how they performed in a test designed to model the complex decision-making and problem-solving present in our everyday lives. Overall, individuals taking the drugs saw small decreases in accuracy and efficiency, along with large increases in time and effort, relative to their results when not taking the drugs.

For example, when given methylphenidate—often used to treat ADHD in children, but increasingly taken by college students cramming for exams—participants took around 50% longer on average to complete the problem as when they were given a placebo.

In addition, participants who performed at a higher level in the placebo condition compared to the rest of the group tended to show a bigger decrease in performance and productivity after receiving a drug.

In contrast, participants who had a lower performance in a placebo condition only very occasionally exhibited a slight improvement after taking a drug.

Professor Peter Bossaerts, Leverhulme International Professor of Neuroeonomics at the University of Cambridge, believes more research needs to be conducted to find out what effects the drugs are having on users without ADHD.

‘Our results suggest that these drugs don’t actually make you ‘smarter,’ said Professor Bossaerts. ‘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.’

He added: ‘Performance did not generally increase, so questions remain about how the drugs are affecting people’s minds and their decision making.’

Dr. Elizabeth Bowman, researcher at the Centre for Brain, Mind and Markets at the University of Melbourne and lead author of the study said the results show we have yet to establish the effectiveness of pharmaceutical enhancers on our performance, when used by neurotypical people to perform everyday complex tasks.

Professor Bowman said: ‘Our research shows drugs that are expected to improve cognitive performance in patients may actually be leading to healthy users working harder while producing a lower quality of work in a longer amount of time.’

The research can be found in the online journal ‘Science Advances’.

Images: Towfiqu barbhuiya