The Cognitive Load of Narrative Lies

Lying is assumed to increase cognitive load, and it has been shown to slow response times to simple questions. We employed a dual‐task methodology, the detection response task (DRT), to assess cognitive load in telling narrative lies in a live, open‐question interview. The DRT requires participants to press a button in response to a tactile stimulus every 3–5 s while performing a primary task, in this case, recounting either truthful or deceitful narratives. We found weak support for slowing in the time to initiate a narrative response when lying. In contrast, we found strong support for an increase in cognitive load when producing a narrative lie, as measured by both slowed DRT responses and increased response omissions, although this effect decreased with time on task. We advocate dual‐task methodologies such as the DRT for increasing understanding of the assumptions made by theories of deception and for refining lie detection techniques.