The Impact of Subjective Cognitive Decline and Mild Cognitive Impairment on Word Association Task Performance

Associative ability can be used as the basic assessment data to clarify semantic knowledge preservation and processing speed by checking semantic networks. Especially due to the nature of Korean language, it takes a long time to build a semantic relation since there are a lot of semantically-overlapping words, particularly more in verbs and adjectives than nouns. And this difference depending on word classes could be a distinctive factor to identify cognitive function problems in the elderly. In this regard, this study aims to find out distinctive performance characteristics observed in the subject groups with subjective memory impairment and mild cognitive impairment, by designing multiple-choice word association tasks by word classes. As a result of the study, it was found that the performance of the mild cognitive impairment group had lower accuracy and reaction time than the normal group, and their error frequency by error types also showed significant difference. The subjective memory impairment group showed a significant increase in reaction time, compare to the normal group. To sum up, the quantity and/or quality of semantic knowledge processing could decline even at the stage of suffering from subjective cognitive problems, and particularly this problem could appear more obviously in the speed of semantic knowledge processing. Therefore, associative processing ability is anticipated to be used as a valuable data in future assessments to identify subjective and/or objective memory problems at an early stage.