1. DETCP, Technical University of Cartagena, Plaza del Hospital, n1, 30202 Cartagena, Spain
2. Department of Automatic Control and Computer Science, Politehnica University of Bucharest, 313 Splaiul Independentei, Bucharest 060042, Romania
3. Division of Psychology, Nottingham Trent University, Burton Street, Nottingham, NG1 4BU, UK
4. Department of Psychology, Lancaster University, Bailrigg, Lancaster, LA1 4YW, UK
5. School of Computer Science, University of Lincoln, Brayford Pool, Lincoln, LN67TS, UK