In October 2001 , he defended his PhD in Psychology at the Free University of Brussels on the subject of cognitive models of human hypertext navigation . He defended his Ph.D. in Psychology from the Free University of Brussels in October 2001 on the subject of cognitive models of human hypertext navigation .
Pada Oktober 2001, beliau mempertahankan PhD dalam Psikologi di Free University of Brussels mengenai subjek model kognitif navigasi hiperteks manusia. Beliau mempertahankan Ph.D. dalam Psikologi dari Free University of Brussels pada Oktober 2001 mengenai subjek model kognitif navigasi hiperteks manusia.