A purpose of this study is to clarify the relationship between the usability of information technology devices in business use and the cognitive characteristics of aged people. A central control room is a workplace often staffed with aging personnel. In order to investigate what kind of a decline in cognitive function of older adults affects their operational abilities, we tested participants who were then classified into three groups according to the type of decline in their cognitive characteristics: a decline in working memory (WM), a decline in visual attention (AT), or a decline in task-switching (TS). In addition, people with completely normal cognitive function were recruited as a control group. A simulator of a central monitoring device was prepared to examine performance of an inspection operation. Reaction time data showed a significant difference between the controls and the WM group (p<.05). For the error ratio, a significant difference was seen between controls and the TS group (p<.05). Performance on the inspection task was negatively affected by the decline in working memory and in task switching. Based on these results, we discuss a design that can compensate for such cognitive aging effects.