1. Department of Behavioral Physiology, Tokyo Metropolitan Institute for Neuroscience, Musashidai, Fuchu, Tokyo 183-8526, Japan
2. Department of Human Sciences and Antiquities, University of Sassari, Piazza Conte di Moriana 8, I 07100 Sassari, Italy
3. BioMedical Area, CRS4 in Sardinia, VI Strada Ovest, Z. I. Macchiareddu, CP 94, I 09010 Uta (CA), Italy