The effect of mastication on human cognitive processing: A study using event-related potentials

Objective: The purpose of the present Study was to clarify the effect of mastication on cognitive processing using reaction time (RT) and event-related potentials (ERPs). Methods: The two experiments consisted of two conditions, Mastication (chewing gum) and Control (relaxing Without chewing gum) in Experiment 1, and law Movement (opening and closing the jaw) and Finger Tapping (tapping the right index finger) in Experiment 2. The subjects performed four sessions of an auditory oddball paradigm. RT and ERPs were recorded in these four sessions, Pre (before chewing), and Post 1, Post 2 and Post 3 (after chewing). Results: In Mastication for RT and the peak latencies of P300 and N100. the values were significantly longer in Pre than in Post 2 or Post 3. By contrast, in Control, jaw Movement, and Finger Tapping, they were almost identical among sessions or significantly shorter in Pre than in Post 2 or Post 3. Conclusions: Mastication influences cognitive processing time as reflected by RT and the latency of ERP waveforms. Significance: This is the first study investigating the effect of mastication on the central nervous system using event-related potentials. (C) 2008 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.