Proceedings of the Annual Meeting of the Cognitive Science Society

How does the mind sustain lengthy, continuous performances?Cognitive processes are continuous, dynamic and adaptive.However, until recently, we didn’t have the methodologicaltools to study these features. In this study, we use DetrendedFluctuation Analysis (DFA) and a sliding window, to analyzethe change in the fractal structure of body movement during thedelivery of an academic lecture. We show that fractal structurevaries widely during performance but also reveals a strongattraction towards 1/f noise. Our analysis also uncover ageneral inverted U pattern in the fractal organization of theperformance: speakers exhibit relatively low exponents (i.e.,less structure) at the beginning of their talk, that then increaseas they get into their performance, and then decrease again asthey finish their narration. This trajectory mirrors the familiaridea of academic lectures as performances in which we set upan argument, develop that argument, and conclude thatargument.