Rationality Drugs

Can drugs improve your rationality?

I’m not sure, but it seems likely.

Remember the cognitive science of rationality. Often, irrationality is a result of ‘mindware gaps’ or ‘contaminated mindware’ — missing pieces of knowledge like probability theory, or wrong ideas like supernaturalism. Alas, we cannot yet put probability theory in a pill and feed it to people, nor can a pill deprogram someone from supernaturalism.

Another cause of irrationality is ‘cognitive miserliness’. We default to automatic, unconscious, inaccurate processes whenever possible. Even if we manage to override those processes with slow deliberation, we usually perform the easiest deliberation possible — deliberation with a ‘focal bias’ like confirmation bias.

What will increase the likelihood of cognitive override and decrease the effect of focal biases? First, high cognitive capabilities (IQ, working memory, etc.) make a brain able to do the computationally difficult processing required for cognitive override and avoidance of focal bias. Second, a disposition for cognitive reflectiveness make it more likely that someone will choose to use those cognitive capabilities to override automatic reasoning processes and reason with less bias.1

Thus, if drugs can increase cognitive capability or increase cognitive reflectiveness, then such drugs may be capable of increasing one’s rationality.

First: Can drugs increase cognitive capability?

Yes. Many drugs have been shown to increase cognitive capability. Here are a few of them:2

  • Modafinil improves working memory, digit span, visual pattern recognition, spatial planning, and reaction time.3

  • Because glucose is the brain’s main energy source,4 increases in glucose availability via sugar injestion should improve memory performance.5

  • Creatine improves cognitive performance.6

  • Donepezil improves memory performance, but perhaps only after taken for 21 days.7

  • Dopamine agonists like d-amphetamine, bromocriptine, and pergolide have all been been found to improve working memory and executive function,8 but perhaps only in those with poor memory performance.9

  • Guanfacine has shown mixed effects on cognition.10 Methylphenidate (Ritalin) has also shown mixed results for cognitive enhancement,11 though the most commonly reported motive for illicit use of prescription stimulants like methylphenidate is to enhance concentration and alertness for studying purposes.12

  • Piracetam is usually prescribed to deal with cognitive deficits and other problems, but also has also shown some cognitive benefits in healthy individuals.13

Second: Can drugs increase cognitive reflectiveness?

I’m not sure. I’m not yet aware of any drugs that have been shown to increase one’s cognitive reflectiveness.

So, can drugs improve your rationality? I haven’t seen any experimental studies test whether particular drugs improve performance on standard tests of rationality like the CRT. However, our understanding of how human irrationality works suggests that improvements in cognitive capability and cognitive reflectiveness (via drugs or other means) should increase one’s capacity to think and act rationally. That said, current drugs probably can’t improve rationality as much as demonstrated debiasing practices can.

Should we use drugs for cognitive enhancement? Scholars debate whether such modifications to human functioning are ethical or wise,14 but I think the simplicity of the transhumanist position is pretty compelling:

If we can make things better, then we should, like, do that.15


1 For a review, see Stanovich (2010), ch. 2.

2 For a broader overview, see de Jongh et al. (2008); Normann & Berger (2008); Sandberg (2011).

3 Muller et al. (2004); Turner et al. (2004); Gill et al. (2006); Caldwell et al. (2000); Finke et al. (2010); Repnatis et al. (2010).

4 Fox et al. (1988).

5 Foster et al. (1999); Sunram-Lea et al. (2002).

6 Rae et al. (2003); McMorris et al. (2006); Watanabe et al. (2002).

7 Gron et al. (2005).

8 D-amphetamine: Mattay et al. (2000); Mattay et al. (2003); Barch & Carter (2005). Bromocriptine: Kimberg et al. (1997); Kimberg et al. (2001); Mehta et al. (2001); Roesch-Ely et al. (2005); Gibbs & D’Esposito (2005a). Pergolide: Muller et al. (1998); Kimberg & D’Esposito (2003).

9 Kimberg et al. (1997); Mehta et al. (2001); Mattay et al. (2000); Mattay et al. (2003); Gibbs & D’Esposito (2005a, 2005b).

10 Muller et al. (2005); de Jongh et al. (2008).

11 de Jongh et al. (2008).

12 Teter et al. (2006).

13 Dimond & Brouwers (1976); Mondadori (1996).

14 Savulescu & Bostrom (2009).

15 I think I first heard Louie Helm put it this way.


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