“…Research has supported the construct validity of TCO, since CO corresponding to mental resources activated during cognitive tasks can be operationalized by psychometric variables measured at the behavioral level. Thus, variables, such as the information processing capacity (M-capacity), logical thinking (LTh), field dependence/independence (FDI), or convergent/divergent thinking (CD), have been proved to play a significant role in a wide range of tasks, and they affect students' performance in science, such as physics (Johnstone, Hogg & Ziane, 1993), chemistry (BouJaoude, Salloum & Abd-El-Khalick, 2004;Chandran, Treagust & Tobin, 1987), organic synthesis (Stamovlasis & Tsaparlis, 2005), physical chemistry (Tsaparlis, 2005), and earth science (Chiappetta & Russell, 1982), to mention a few. Recently, three of the above-mentioned cognitive variables-LTh, FDI, and CD-were found to affect students' mean achievement score on the topic of the structure of matter and its changes of state (Tsitsipis, Stamovlasis & Papageorgiou, 2010).…”