Musicians can become stressed and frustrated with mistakes, especially portions of a musical work that they find difficult to play accurately. Rather than tensing up and becoming worried, try replaying the passage and just be aware of notes that are inaccurate. List them in your mind. Placing yourself in an awareness mode encourages the conscious mind to listen to what is happening. This can increase the feedback the mind gives you. This can trigger positive changes, sometimes without great amounts of effort. (Green, Barry, with W. Timothy Gallwey. The Inner Game of Music, p. 47. NY: Doubleday, 1986.)