The effects of distortion on learning of the coordination task. Squares represent the C condition, circles represent the ITB condition, and triangles represent the TIB condition. (a) The normalized error for the index finger. The change from section 2 to 3 for the ITB condition is significantly different from that of the controls. (b) The normalized error for the thumb. Again, the change from section 2 to 3 for controls was significantly different from that for subjects in the ITB condition. No differences were found between control and TIB subjects.