1. BACKGROUND:<br/>Professional percussionists have acquired specialized movement patterns that allow them to control timing and striking force in detail. Although such movement patterns can differ considerable between players and playing conditions, the hand movements typically display smooth, wavelike features where the stick is accelerated in a whipping motion (see eg Dahl, 2004; 2006).<br/><br/>For more extreme tempi and dynamic levels, controlling the stick movement becomes increasingly difficult, sometimes resulting in irregularities in timing and/or striking force. Timing irregularities can also be a revealing sign of motor control problems, such as focal dystonia (Jabusch, Vauth & Altenmüller, 2004). The "breakdown" in motor control can therefore be expected to result in more pronounced changes in movement pattern of the affected arm for these patients. <br/><br/>Because drumming movements tend to be symmetrical, studying the movements of percussionists offers a promising method of comparing healthy and disturbed moving patterns for individual players.<br/><br/>2. AIMS:<br/><br/>To investigate the influence of nominal tempo on movement pattern and timing variability for healthy percussionists and those suffering from focal dystonia.<br/><br/><br/>3. METHOD:<br/><br/>The arm, hand, and stick movements of four professional percussionists were recorded using a motion capture system. Two of the players are focal dystonia patients with their left arm affected. For each player and arm 25 s of single strokes at different tempi (50, 120, 300 bpm) and dynamic levels (p, mf, f) were recorded. The motion data was analyzed with respect to general movement pattern, variability in timing and striking force.<br/><br/>4. RESULTS:<br/>Preliminar results show a deterioration in movement patterns for the faster tempi, typically with a stiffening of joints and lack of timing control. As expected, the disturbed patterns were more pronounced for the patients' affected arm compared to the non affected and the healthy players. The onset of deterioration also occurred early for the patients' affected arm, at fast tempo already at the beginning of the recorded trial. <br/><br/>5. CONCLUSIONS:<br/>At this early stage, the results should not be generalized. However, this type of research could provide valuable insights in how movement patterns change in response to more demanding playing conditions. Such knowledge would have important implications for music teaching and education.