Generalization of context-specific training in individuals with mild cognitive impairment : an event-related potential study

Abstract

Background: This study examined the neural processes associated with the generalization of the effect of context-specific (CS) training to noncontextual situations among individuals with mild cognitive impairment (MCI). Methods: Fourteen and 16 participants with MCI were randomly allocated to a Chinese calligraphy writing (CW) training or a control group, respectively. The CW participants learned how to write Chinese strokes in a semicursive style to construct characters, tapping on working memory functions. The control group, on the other hand, learned how to use a tablet computer without emphasis on working memory functions. They then performed two 2-back tasks with CS semicursive strokes and non-context-specific (NCS) digits. Event-related electroencephalogram signals were concurrently recorded. Results: The CW participants had a significantly shorter reaction time in the CS than in the NCS task (p < 0.05). They showed significantly longer latency in working memory updating (N200; t11 = 4.70, p = 0.05) and shorter latency in the evaluation of visual representation (P300; t12 = 4.67; p = 0.05) than the control group when performing the 2-back CS task. Shorter P300 latency was also revealed in the 2-back NCS task (t12 = 5.15, p = 0.041), suggesting a possible generalization of the training effect among the CW participants. Conclusion: The results suggest that CS working memory is likely to be generalized to NCS domains among individuals with MCI. Future research should extend the scope of the generalization and apply it beyond experimental conditions.