Dorien Bangma

FDM AND NORMAL AGING | 53 situations an individual may encounter in daily life. Furthermore, in spite of the theoretical classification of different FDM aspects and the weak correlations found between FDM tasks, it is possible that in some cases certain tasks relate to similar constructs or aspects of FDM. A third limitation of the present study is that the convergent validity could not be evaluated since there are hardly any additional FDM tests available. In addition, the ecological validity of the FDM tests was not examined so far by exploring the associations between the performances on the FDM tests and real-life FDM problems. Fourth, it must be noted that the effects of age on FDM might have been confounded by the fixed sequence of test administration and differences in the assessment procedure of sample 1 and 2 (Appendix 3-1). However, by using the same sequence of FDM tests in sample 1 and 2 and providing participants the opportunity for as much breaks as needed the effects of the test administration order were likely kept on a minimum. Finally, the role of financial experience and knowledge was not taken into account sufficiently. Nevertheless, by investigating multiple aspects of FDM, a better understanding of age- related differences in FDMwas obtained. Normal aging influences some aspects of FDM, while other aspects appear to be unaffected by normal aging. Age-related decline in FDM, which is possibly related to normal age-related changes in the prefrontal networks (Dennis & Cabeza, 2008; Maillet & Rajah, 2013), seems to be mediated by age-related changes in executive functions (Braver & West, 2008; Denburg & Hedgcock, 2015), particularly in planning and numeracy. However, also working memory was found to be predictor of FDM. Improved affective decision-making and an age-related increase of knowledge and experience in older individuals (Hess, 2015; Li et al., 2004; Mikels et al., 2013; Peters et al., 2007) might result in stable or improved FDM with advancing age. In future research the role of motivation during complex FDM situations, such as applying decision rules, needs further investigation since an older age has been associated with a lack of motivation for difficult or complex (decision- making) situations (Bruine de Bruin et al., 2015). Furthermore, it would be interesting to further explore individual differences in FDM by focusing on the effects of gender, financial resources and level of education, since it is generally known that demographic characteristics have an effect on neuropsychological test performances (van der Elst et al., 2006a, 2006b, 2006c) and might have a mediating or moderating influence on the effects of age on FDM. In addition, studying FDM in patient groups, such as patients with neurodegenerative disorders, attention- deficit/hyperactivity disorder or traumatic brain injury, is of utmost importance since it can be expected that these patients experience problems with FDM in daily life due to more severe impairments in cognition (e.g., Barkley et al., 2008; Dreer et al., 2012; Earnst et al., 2001; Lui et al., 2013; Martin et al., 2013; Sherod et al., 2009) than found in healthy (older) adults. Finally, it is relevant to relate the current FDM tests to everyday situations and problems in FDM to determine the ecological validity of the different FDM tests.