The two mirrors are fascinating in the sense that they look at each other and reflect each other's reflection, while the original does not exist. Doesn't this strike you as something familiar? Isn't this the phenomenon that happens in our mind at all times? Of course, this is a metaphor for consciousness. The mirror, the twins, and the illusion - you will find all this in the paper of Samsonovich and Ascoli on page 621. How are these higher abstract concepts implemented in neuronal networks of the brain? A possible answer is given by Samsonovich and Nadel on page 669.
The cover illustration was created by Dr. Gail Scott White, who is a professional artist and a Professor of Fine Arts at George Mason University. This her work was inspired by a conversation with Dr. Giorgio Ascoli and Dr. Alexei Samsonovich, who subsequently proposed her work as the cover for the journal issue. The neurons that you see on the top of the heads are pyramidal CA3 cells. Half of them are real reconstructions, and the other half are generated with a rather simple mathematical algorithm designed by Alexei Samsonovich and Giorgio Ascoli.