[1] 23 Rue Lavandieres, F-11160 Caunes Minervois, France
[2] Tufts Univ, Allen Discovery Ctr, Medford, MA 02155 USA
[3] UCL, Wellcome Ctr Human Neuroimaging, London WC1N 3AR, England
[4] Eastern Illinois Univ, Dept Math & Comp Sci, Charleston, IL 61920 USA
[5] Univ Illinois, Adjunct Fac, Dept Math, Urbana, IL 61801 USA
[6] Harvard Univ, Wyss Inst Biolog Inspired Engn, Wyss Inst Biolog Inspired Engn, Boston, MA 02115 USA
[7] Fudan Univ, Ctr Field Theory & Particle Phys, Dept Phys, Shanghai, Peoples R China
[8] Lab Nazl Frascati INFN, Rome, Italy
[9] INFN Sez Roma Tor Vergata, I-00133 Rome, Italy