A Test of the Cognitive Load Hypothesis: Investigating the Impact of Number of Nonverbal Cues Coded and Length of Coding Session on Observer Accuracy

In their meta-analysis investigating the relationship between extraversion and nonverbal behavior La France, Heisel, and Beatty (2004 La France , B. H. , Heisel , A. D. , & Beatty , M. J. ( 2004 ). Is there empirical evidence for a nonverbal profile of extraversion: A meta-analysis and critique of the literature . Communication Monographs , 71 , 28 – 48 .[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) found a substantial negative correlation between effect size and sample size, which they explained using the cognitive load hypothesis. The cognitive load hypothesis predicts that increases in coding scheme complexity result in greater opportunities for observer error. To test this hypothesis, the impact of coding scheme complexity on observer error was assessed via varying the number of nonverbal cues coded and the length of observational coding session. The decision to increase the number of nonverbal cues observers coded created 26% more errors, and over time observers made 10% more errors.