Original Investigation

Psychopharmacology

, Volume 222, Issue 3, pp 419-424

Open Access This content is freely available online to anyone, anywhere at any time.

Propranolol reduces implicit negative racial bias

  • Sylvia TerbeckAffiliated withDepartment of Experimental Psychology, University of Oxford Email author 
  • , Guy KahaneAffiliated withOxford Uehiro Centre for Practical Ethics, University of Oxford
  • , Sarah McTavishAffiliated withDepartment of Psychiatry, Neurosciences Division, University of Oxford, Warneford Hospital
  • , Julian SavulescuAffiliated withOxford Uehiro Centre for Practical Ethics, University of Oxford
  • , Philip J. CowenAffiliated withDepartment of Psychiatry, Neurosciences Division, University of Oxford, Warneford Hospital
  • , Miles HewstoneAffiliated withDepartment of Experimental Psychology, University of Oxford

Abstract

Background

Implicit negative attitudes towards other races are important in certain kinds of prejudicial social behaviour. Emotional mechanisms are thought to be involved in mediating implicit “outgroup” bias but there is little evidence concerning the underlying neurobiology. The aim of the present study was to examine the role of noradrenergic mechanisms in the generation of implicit racial attitudes.

Methods

Healthy volunteers (n = 36) of white ethnic origin, received a single oral dose of the β-adrenoceptor antagonist, propranolol (40 mg), in a randomised, double-blind, parallel group, placebo-controlled, design. Participants completed an explicit measure of prejudice and the racial implicit association test (IAT), 1–2 h after propranolol administration.

Results

Relative to placebo, propranolol significantly lowered heart rate and abolished implicit racial bias, without affecting the measure of explicit racial prejudice. Propranolol did not affect subjective mood.

Conclusions

Our results indicate that β-adrenoceptors play a role in the expression of implicit racial attitudes suggesting that noradrenaline-related emotional mechanisms may mediate negative racial bias. Our findings may also have practical importance given that propranolol is a widely used drug. However, further studies will be needed to examine whether a similar effect can be demonstrated in the course of clinical treatment.

Keywords

Noradrenaline Propranolol Implicit racial bias Explicit prejudice