When we discuss memories, we often mean memories of facts and events: What you did last Sunday, the capital of Austria, your best friend’s cell phone number.

There is another kind of memory that is largely unconscious, but very important. We learn and remember essential skills, such as walking, using chopsticks, or riding a bicycle.

The mirror-tracing activity is a visual and motor test that involves learning a new motor skill. The task requires you to move a pencil to trace the diagram of a star while looking at your hand only as a reflection in a mirror. The act of drawing is a learned skill that requires visual and proprioceptive feedback to control muscle movement.