Can metaphors sway public opinion on cognitive enhancers?

10 May 2019

Banner image

We all have opinions on controversial issues, but could the way we are presented with information change our stance on the subject? Researchers at the University of Pennsylvania investigated if using different metaphors could sway public opinion on cognitive enhancers.

What are cognitive enhancers?

In today’s society, there is an increase in work-related stress, lack of sleep, shift work and long hours all of which contribute to the decline of cognitive function. Cognitive abilities are considered essential for successful performance and advancement. High-pressure environments that range from schools to offices push people to use cognitive enhancers. Cognitive enhancers are defined as “interventions in humans that aim to improve mental functioning beyond what is necessary to sustain or restore good health”. There are two categories of cognitive enhancer pharmacological (PCE) and non-pharmacological (NPCE). Computer training, meditation, physical exercise, and sufficient sleep are all examples of non-pharmacological cognitive enhancers. The term pharmacological cognitive enhancers commonly refers to the use of drugs originally designed to treat ADHD or narcolepsy to increase the mental performance of healthy individuals. Common examples of these drugs include Ritalin (methylphenidate), Adderall (mixed amphetamine salts), and Provigil (modafinil). Sugar (glucose) and caffeine are also examples of pharmacological cognitive enhancers.

Limited effectiveness of pharmacological cognitive enhancers

Both methylphenidate and modafinil have muted effects on healthy individuals. The optimal concentration of neurotransmitters (e.g. dopamine, norepinephrine, serotonin) within the brain is a delicate balance and having concentrations that are either too high or too low can result in cognitive dysfunction. This is why people who have an imbalance (ADHD, narcolepsy) benefit the most from these drugs and why healthy individuals may not experience the same positive effect. In fact, the increase in cognitive function gained from pharmacological enhancers is similar to those gained from non-pharmacological enhancers (e.g. sufficient sleep and physical activity). The publics’ perception of pharmacological enhancers appears to be they are more effective which is simply not the case.

Public perception of pharmacological cognitive enhancers.

The public has three main concerns when it comes to pharmacological cognitive enhancers namely safety, coercion and fairness. Medical safety is the main concern around the off-label use of these drugs with particular concern for the short and long term side effects. Coercion relates to explicit and implicit pressures that force individuals to take these substances to be competitive. Fairness is a broad topic with three main categories equal distribution, honesty and authenticity. Equal distribution relates to who has access to the enhancers. Is it available to everyone or only the wealthy? Honestly pertains to whether taking the enhancers constitute cheating in competitive environments. Finally, authenticity is associated with how much effort is put into reaching a goal and whether taking cognitive enhancers that reduce this effort renders achievements inauthentic. The attitudes regarding these concerns vary depending on the groups being asked (parents, users, non-users, medical practitioners). Generally, there is an overall moderately negative perception of using cognitive enhancers. Students and academics are consulted most often with regard to the use of cognitive enhancers and the attitude of the general public is not well understood.

Metaphors are an excellent way of conveying complex information to people with limited experience with a particular topic. The drawback with using metaphors is that they provide a framework for viewing a problem and can often impart subtle emotional connotations. How metaphors influence the attitudes of the general public toward cognitive enhancers is unknown.

Can metaphors sway public opinion on cognitive enhancers?

In a recent US study published in AJOB Neuroscience, researchers wanted to understand how the publics’ opinion on cognitive enhancers were affected by using different metaphors. The scientists used Amazon’s Mechanical Turk platform to perform three separate surveys. A total of 3,700 participants from across the United States participated. Each survey framed the use of cognitive enhancers with different metaphors. An example would be “Cognitive enhancing pills are [fuel/steroids] for the brain.” The researchers then determined the level acceptability the participants had for taking cognitive enhancing pills in these differing situations. They also measured whether the participants would support the use of cognitive enhance pills by others and by themselves.

The group found some interesting results, the participants were more likely to approve of cognitive enhancing pills in others but not for themselves. This was particularly true when the fuel metaphor was used. The scientists speculate this is because fuel emphasises maximizing potential while steroids imply minimizing effort. Minimizing effort is associated with the inauthentic achievement which was one of the common concerns regarding fairness. The other implicit differences between these metaphors is that fuel is necessary to function while steroids are not, steroids also have unwanted side effects. This highlights the public’s concern for medical safety. What was interesting was the metaphors used had no effect on how the participants viewed self-use. It seems that metaphors are capable of changing public opinion that can affect policy but would not affect individual behaviour.

The study also explored whether cognitive enhancement was more acceptable in students, athletes or the workforce. The researchers found that it was more acceptable for employees to use cognitive enhancement pills than students and athletes. They also noted that participants thought it was more acceptable to use cognitive enhancement in highly competitive environments.

The way information is presented to us can affect what stance we take on cognitive enhancers. It is clear then that policymakers, health care practitioners, teachers and parents should think critically about the language they use when discussing this topic. It is also helpful to be aware of how information is presented to you and whether or not it has implicit bias.

Dr. Chatterjee, a lead author, had this to say about the study “These findings highlight the importance of involving the general public in discussions about attitudes towards cognitive enhancement and the effect framing can have on them.”


  1. Caviola, L. & Faber, N. S. Pills or push-ups? Effectiveness and public perception of pharmacological and non-pharmacological cognitive enhancement. Frontiers in Psychology 6, 1852 (2015).
  2. Schelle, K. J., Faulmüller, N., Caviola, L. & Hewstone, M. Attitudes toward pharmacological cognitive enhancement—a review. Frontiers in systems neuroscience 8, 53 (2014).
  3. Bruhl, A. B. & Sahakian, B. J. Drugs, games, and devices for enhancing cognition: implications for work and society. Ann N Y Acad Sci 1369, 195-217, doi:10.1111/nyas.13040 (2016).
  4. Dresler, M. et al. Hacking the Brain: Dimensions of Cognitive Enhancement. ACS Chem Neurosci 10, 1137-1148, doi:10.1021/acschemneuro.8b00571 (2018).
  5. Conrad, E. C., Humphries, S. & Chatterjee, A. Attitudes toward cognitive enhancement: the role of metaphor and context. AJOB neuroscience 10, 35-47 (2019).
  6. Messinger, H. Cognitive enhancers to boost abilities at work considered acceptable by the public, (2019).