Motor Control, 2021, 25, 182–197 https://doi.org/10.1123/mc.2020-0061 © 2021 Human Kinetics, Inc. ARTICLE The Interaction Between Long-Term Memory and Postural Control: Different Effects of Episodic and Semantic Tasks Maëlle Tixier Université Grenoble Alpes Corinne Cian Université Grenoble Alpes and Institut de Recherche Biomédicale des Armées Pierre-Alain Barraud, Rafael Laboissiere, and Stéphane Rousset Université Grenoble Alpes The aim of this experiment was to investigate the postural response to specific types of long-term memory (episodic vs. semantic) in young adults performing an unperturbed upright stance. Although a similar level of steadiness (mean distance) was observed, dual tasking induced a higher velocity, more energy in the higher frequency range (power spectral density), and less regularity (sample entropy) compared with a simple postural task. Moreover, mean velocity was always greater in the semantic than in the episodic task. The differences in postural control during dual tasking may result from the types of processes involved in the memory task. Findings suggest a spatial process sharing between posture and episodic memory. Keywords: dual tasking, spatial processing, episodic memory, semantic memory Postural control in everyday life is generally accompanied by posture- unrelated cognitive activity. However, a large body of research has shown that balance and cognitive tasks (i.e., suprapostural tasks) may interfere with each other (for a review, see Bayot et al., 2018). The pattern of observed interaction between postural and suprapostural tasks varies across studies from postural (or cognitive) facilitation or interference (one performance remains stable while the other improves or deteriorates) to mutual facilitation or interference (performance of both tasks improves or deteriorates) (for a review, see Plummer et al., 2013). Tixier, Cian, Laboissiere, and Rousset are with the Université Grenoble Alpes, CNRS LPNC UMR 5105, Grenoble, France. Cian is with the Institut de Recherche Biomédicale des Armées, Brétigny sur Orge, France. Barraud is with the Université Grenoble Alpes, CNRS, CHU Grenoble-Alpes, Grenoble INP, TIMC-IMAG, Grenoble, France. Rousset (stephane.rousset@univ-grenoble-alpes.fr) is corre- sponding author. 182 Unauthenticated | Downloaded 04/16/21 04:14 AM UTC