Lying relies on the truth q Evelyne Debey a,⇑ , Jan De Houwer a , Bruno Verschuere a,b,c a Faculty of Psychology and Educational Sciences, Department of Experimental-Clinical and Health Psychology, Ghent University, Ghent, Belgium b Faculty of Social and Behavioural Sciences, Department of Clinical Psychology, University of Amsterdam, Amsterdam, The Netherlands c Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands article info Article history: Received 9 May 2013 Revised 22 April 2014 Accepted 25 April 2014 Keywords: Deception Cognitive processes Truth activation Distractors abstract Cognitive models of deception focus on the conflict-inducing nature of the truth activation during lying. Here we tested the counterintuitive hypothesis that the truth can also serve a functional role in the act of lying. More specifically, we examined whether the construction of a lie can involve a two-step process, where the first step entails activating the truth, based upon which a lie response can be formulated in a second step. To investigate this hypothesis, we tried to capture the covert truth activation in a reaction-time based decep- tion paradigm. Together with each question, we presented either the truth or lie response as distractors. If lying depends on the covert activation of the truth, deceptive responses would thus be facilitated by truth distractors relative to lie distractors. Our results indeed revealed such a ‘‘covert congruency’’ effect, both in errors and reaction times (Experiment 1). Moreover, stimulating participants to use the distractor information by increasing the proportion of truth distractor trials enlarged the ‘‘covert congruency’’ effects, and as such confirmed that the effects operate at a covert response level (Experiment 2). Our findings lend support to the idea that lying relies on a first step of truth telling, and call for a shift in theoretical thinking that highlights both the functional and interfering properties of the truth activation in the lying process. Ó 2014 Elsevier B.V. All rights reserved. 1. Introduction A growing body of evidence supports the long held assumption that lying is more cognitively demanding than truth telling (Vrij, Fisher, Mann, & Leal, 2006; Zuckerman, DePaulo, & Rosenthal, 1981). Behavioral research, for example, has shown that the additional cognitive processes involved in lying are reflected in longer latencies and a higher error rate compared to truth telling (see Verschuere & De Houwer, 2011, for a review). Brain imaging studies have also demonstrated that, in contrast to truth telling, the act of lying involves more activity in prefrontal brain regions (anterior cingulate, dorsolateral prefrontal, and inferior frontal regions) that are known to be crucially involved in cognitive control (see Abe, 2011; Christ, Essen, Watson, Brubaker, & McDermott, 2009, for reviews). The idea that cognitive control plays a key role in deception is further bolstered by studies showing that the ability to deceive is poor in children, whose prefrontal cortex development is not yet complete (Hala & Russell, 2001; Talwar & Lee, 2008), and in patients with neurodevel- opmental and neurodegenerative conditions of the frontal lobe, such as autism and Parkinson’s disease (Abe, 2009). Despite the increasing interest in the cognitive aspect of deception, research that has attempted to unravel the underlying mechanisms as to why lying is more mentally challenging, remains relatively limited. So far, most http://dx.doi.org/10.1016/j.cognition.2014.04.009 0010-0277/Ó 2014 Elsevier B.V. All rights reserved. q Evelyne Debey is supported by Ghent University Grant BOF01D01010. Jan De Houwer is supported by Ghent University Grant BOF09/01M00209. ⇑ Corresponding author. Address: Department of Experimental Clinical and Health Psychology, Ghent University, Henri Dunantlaan 2, 9000 Ghent, Belgium. Tel.: +32 (0)9 264 94 46. E-mail address: evelyne.debey@ugent.be (E. Debey). Cognition 132 (2014) 324–334 Contents lists available at ScienceDirect Cognition journal homepage: www.elsevier.com/locate/COGNIT