Influence of the ability to roll the tongue and tongue-training parameters on oral motor performance and learning M. Kothari a, *, P. Svensson a,b , A. Basic a , B. Christiansen a , M. Vigsø a , L. Truc a , L. Baad-Hansen a a Department of Clinical Oral Physiology, School of Dentistry, Aarhus University, Denmark b MINDLab, Center for Functionally Integrative Neuroscience, Aarhus University Hospital, Denmark 1. Introduction Relearning of motor skills is an important part of rehabilitation for patients with acquired brain damage. The human tongue is involved in various essential and complex functions. 1–4 A rapid and effective control of the tongue musculature is required in many daily oral functions like chewing, swallow- ing and speech. 2–4 The swallowing process consists of a highly complex and semiautomatic sequence of events involving intrinsic and extrinsic tongue musculature leading to protection of the airways during food ingestion. 5 Rehabilitation of oral functions in patients with difficulty in swallowing is mainly based on a r c h i v e s o f o r a l b i o l o g y 5 6 ( 2 0 1 1 ) 1 4 1 9 – 1 4 2 3 a r t i c l e i n f o Article history: Accepted 28 April 2011 Key words: Tongue-training Rehabilitation Motor performance Tongue rolling ability a b s t r a c t Objective: Training of tongue function is an important part of rehabilitation of patients with brain damage. A standardized tongue-training task has been shown to induce cortical plasticity. This study tested the possible influence of the natural ability to roll the tongue and modulations of tongue-training parameters on tongue-training performance. Design: A total of 44 healthy adult subjects participated. 29 subjects (15 with and 14 without ability to roll their tongue) performed 1 h standard tongue-training task. Another 15 subjects participated in 2 sessions: Standard and Modulation in randomized order. Standard session: 1 h tongue-training with fixed training parameters; Modulation session: 1 h tongue-training with modulation of training parameters every 20 min (3 different settings – A, B, C, with different timing of task). Perceived task difficulty was evaluated on a 0–10 numerical rating scale (NRS). Results: All participants improved performance during training (P < 0.001). The ability to roll the tongue did not influence tongue-training performance (P = 0.617). Modulation of training parameters influenced baseline training performance (P < 0.018) and improvement (P = 0.039). The mean perceived difficulty on NRS was: Standard: 6 Æ 2; Modulation: A: 6 Æ 2; B: 7 Æ 1; C: 4 Æ 1. Perceived task difficulty (r = À0.740, P < 0.001) and performance improvement (r = À0.610, P < 0.001) were inversely correlated with baseline training performance. Conclusion: The natural ability to roll the tongue did not influence tongue-training perfor- mance. Modulation of tongue-training parameters by alteration of timing of the training task influenced tongue-training performance and perceived task difficulty. # 2011 Elsevier Ltd. All rights reserved. * Corresponding author. E-mail address: mohit.kothari@odontologi.au.dk (M. Kothari). availab le at www .s cien c edir ect .co m journal homepage: http://www.elsevier.com/locate/aob 0003–9969/$ – see front matter # 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.archoralbio.2011.04.017