Giovanni Pezzulo Institute of Cognitive Sciences and Technologies (ISTC)-CNR, Via S. Martino della Battaglia 44, I-00185 Rome, Italy.
Email: giovanni.pezzulo[A@T]istc.cnr.it

Martin V. Butz Dep. of Psychology, University of Würzburg, Röntgenring 11, 97070 Würzburg, Germany
Email: butz[A@T]psychologie.uni-wuerzburg.de

Olivier Sigaud Institut des Systèmes Intelligents et de Robotique (ISIR) - Université Pierre et Marie Curie (UPMC) - Paris6, CNRS FRE 2507 - 4 place Jussieu, F75252 Paris Cedex 05
Email: olivier.sigaud[A@T]lip6.fr

Gianluca Baldassarre Institute of Cognitive Sciences and Technologies (ISTC)-CNR, Via S. Martino della Battaglia 44, I-00185 Rome, Italy.
Email: gianluca.baldassarre[A@T]istc.cnr.it