Dissertations, Theses, and Capstone Projects

Date of Degree


Document Type


Degree Name





Maria Hartwig


Deryn Strange

Committee Members

Deryn Strange

Steven Penrod

Aldert Vrij

Michael Kane

Subject Categories

Cognitive Psychology | Criminology and Criminal Justice | Experimental Analysis of Behavior


deception detection, investigative interviewing, working memory capacity


Two studies are presented. The purpose of the first study is to examine the moderating impact of working memory capacity (WMC) on the cognitive load produced by both the type of statement a person is making and the manner in which the person is interviewed in a mock crime scenario. The moderating impact of suspects’ WMC (measured using the automated operation span task) on this process was also assessed. Suspects were instructed to tell the truth, a relatively easy lie, or a more difficult lie. Suspects were then interviewed in a relatively easy manner, a moderately more difficult manner, or a very difficult manner. The purpose of the second study is to examine how the factors of the first study affected observers’ judgments of the suspects. Observers were asked to either directly assess the veracity of the suspects, or indirectly assess it by observing the suspects’ experienced cognitive load. The results overall did not support the hypotheses and demonstrated that deception was not cognitively more difficult from telling the truth and that the use of cognitive load was not helpful in the process of accurately determining the guilt or innocence of the suspects.