The Mirror-Tracing Task The task is to trace the outline of a star (or some other shape) with a metal stylus when the star and your hand can be seen only in the mirror. Thus, the tracing movements have to be made in the direction opposite from the way in which they appear in the mirror. When the stylus moves off of the star outline (each red section in the illustrated tracing), it makes electrical contact with the underlying aluminum plate and a tracing error is recorded. There is nonconducting tape on the star outline so as long as the stylus stays on the outline, no electrical contact is made. Just like we would, H. M. improved from session to session (the number of errors he made decreased) as he gained more experience in this task. However, unlike us, he could not remember ever having performed the task before and had to have the task explained to him each session. As explained in the text, this means that he formed new implicit procedural memories for how to do the task, but he did not form new explicit episodic memories of having performed the task.