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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Di­mond & Brouw­ers (1976). In­crease in the power of hu­man mem­ory in nor­mal man through the use of drugs. Psy­chophar­ma­col­ogy, 49: 307–309.

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Foster, Lid­der, & Sun­ram (1998). Glu­cose and mem­ory: frac­tiona­tion of en­hance­ment effects? Psy­chophar­ma­col­ogy, 137: 259–270.

Fox, Raichle, et at. (1988). Nonox­ida­tive glu­cose con­sump­tion dur­ing fo­cal phys­iologic neu­ral ac­tivity. Science, 241: 462–464.

Gibbs & D’Es­pos­ito (2005a). In­di­vi­d­ual ca­pac­ity differ­ences pre­dict work­ing mem­ory perfor­mance and pre­frontal ac­tivity fol­low­ing dopamine re­cep­tor stim­u­la­tion. Cog­ni­tive & Affec­tive Be­hav­ioral Neu­ro­science, 5: 212–221.

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Mat­tay, Cal­li­cott, et al. (2000). Effects of dex­troam­phetamine on cog­ni­tive perfor­mance and cor­ti­cal ac­ti­va­tion. Neu­roimage, 12: 268–275.

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Mul­ler, Clark, et al. (2005). Lack of effects of guan­facine on ex­ec­u­tive and mem­ory func­tions in healthy male vol­un­teers. Psy­chophar­ma­col­ogy (Ber­lin), 182: 205–213.

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