Limits...
Mediating effect of executive function on memory in normal aging adults.

Kim MJ, Kwon JS, Shin MS - Psychiatry Investig (2013)

Bottom Line: In terms of auditory-verbal memory, the effect of aging on memory was fully mediated by executive function.Gender differences were not significant in this model.Aging is not the only factor that drives memory decline, and its direct, adverse effect on memory was more prominent in the visuo-spatial memory task than auditory-verbal memory task.

View Article: PubMed Central - PubMed

Affiliation: Department of Child and Adolescent Psychiatry, Seoul National University Hospital, Seoul, Republic of Korea.

ABSTRACT

Objective: We hypothesize that the effect of aging on memory is mediated by executive function.

Methods: Two hundred and thirty healthy adults (101 male, 129 female) were recruited for the study. We used a promising, newly developed, computerized neuropsychological test for the measurement of executive function and memory. The data were analyzed using structural equation modeling and path analysis.

Results: The full mediation model showed a good fit to the data. However, chi-squared (χ(2)) tests for model comparison indicated that the partial mediation model better fits our data. Thus, the partial mediation model was used as the final model. In terms of auditory-verbal memory, the effect of aging on memory was fully mediated by executive function. However, visuo-spatial memory was significantly affected both indirectly (through executive function) and directly (by aging). Gender differences were not significant in this model.

Conclusion: This study demonstrated the importance of executive function in the memory functioning of normal aging adults. It is noteworthy that modality differences were found between auditory-verbal and visuo-spatial memory. Aging is not the only factor that drives memory decline, and its direct, adverse effect on memory was more prominent in the visuo-spatial memory task than auditory-verbal memory task. Since performance in both modalities is fully or partially mediated by executive function, it is important to train normal aging adults in executive control skills, such as planning, strategy formation, and rapid decision making.

No MeSH data available.


Related in: MedlinePlus

Partial mediation model (final model). Arrows reflect relationships between variables, and the dashed line re-presents a nonsignificant association. Standardized regression coefficients are shown next to each path. **p<0.01, ***p< 0.001. VM: verbal memory, VSM: visuo-spatial memory, IR: immediate recall, DR: delayed recall, IRG: immediate recognition, DRG: delayed recognition, TMT: Trail Making Test. Higher scores on the TMT-A and TMT-B indicate impairment, Ex: executive function.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3687043&req=5

Figure 3: Partial mediation model (final model). Arrows reflect relationships between variables, and the dashed line re-presents a nonsignificant association. Standardized regression coefficients are shown next to each path. **p<0.01, ***p< 0.001. VM: verbal memory, VSM: visuo-spatial memory, IR: immediate recall, DR: delayed recall, IRG: immediate recognition, DRG: delayed recognition, TMT: Trail Making Test. Higher scores on the TMT-A and TMT-B indicate impairment, Ex: executive function.

Mentions: In order to determine the direct effect of aging on memory, we created a partial mediation model, Model 2 (Figure 3). Model 1 was nested in Model 2 so that we could compare these models by using the χ2 test of difference. We created Model 2 by adding two additional pathways to Model 1; thus, Model 2 had two additional restrictions and fewer free parameters. Compared with Model 1, Model 2 lost two degrees of freedom, which resulted in the following values: Δχ2=7.14 (p<0.05)(χ2 critical value=5.99 at the p<0.05 level). Δχ2 was significant at the 0.05 level, indicating that Model 2 provided a better explanation of our data than Model 1. Moreover, all of the traditional fit indices were better for Model 2 (χ2=12.46, df=15, p=0.644, TLI=1.006, CFI=1.000, RMSEA=0.000) than for Model 1. Therefore, the partial mediation model was accepted as the final model for this study.


Mediating effect of executive function on memory in normal aging adults.

Kim MJ, Kwon JS, Shin MS - Psychiatry Investig (2013)

Partial mediation model (final model). Arrows reflect relationships between variables, and the dashed line re-presents a nonsignificant association. Standardized regression coefficients are shown next to each path. **p<0.01, ***p< 0.001. VM: verbal memory, VSM: visuo-spatial memory, IR: immediate recall, DR: delayed recall, IRG: immediate recognition, DRG: delayed recognition, TMT: Trail Making Test. Higher scores on the TMT-A and TMT-B indicate impairment, Ex: executive function.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3687043&req=5

Figure 3: Partial mediation model (final model). Arrows reflect relationships between variables, and the dashed line re-presents a nonsignificant association. Standardized regression coefficients are shown next to each path. **p<0.01, ***p< 0.001. VM: verbal memory, VSM: visuo-spatial memory, IR: immediate recall, DR: delayed recall, IRG: immediate recognition, DRG: delayed recognition, TMT: Trail Making Test. Higher scores on the TMT-A and TMT-B indicate impairment, Ex: executive function.
Mentions: In order to determine the direct effect of aging on memory, we created a partial mediation model, Model 2 (Figure 3). Model 1 was nested in Model 2 so that we could compare these models by using the χ2 test of difference. We created Model 2 by adding two additional pathways to Model 1; thus, Model 2 had two additional restrictions and fewer free parameters. Compared with Model 1, Model 2 lost two degrees of freedom, which resulted in the following values: Δχ2=7.14 (p<0.05)(χ2 critical value=5.99 at the p<0.05 level). Δχ2 was significant at the 0.05 level, indicating that Model 2 provided a better explanation of our data than Model 1. Moreover, all of the traditional fit indices were better for Model 2 (χ2=12.46, df=15, p=0.644, TLI=1.006, CFI=1.000, RMSEA=0.000) than for Model 1. Therefore, the partial mediation model was accepted as the final model for this study.

Bottom Line: In terms of auditory-verbal memory, the effect of aging on memory was fully mediated by executive function.Gender differences were not significant in this model.Aging is not the only factor that drives memory decline, and its direct, adverse effect on memory was more prominent in the visuo-spatial memory task than auditory-verbal memory task.

View Article: PubMed Central - PubMed

Affiliation: Department of Child and Adolescent Psychiatry, Seoul National University Hospital, Seoul, Republic of Korea.

ABSTRACT

Objective: We hypothesize that the effect of aging on memory is mediated by executive function.

Methods: Two hundred and thirty healthy adults (101 male, 129 female) were recruited for the study. We used a promising, newly developed, computerized neuropsychological test for the measurement of executive function and memory. The data were analyzed using structural equation modeling and path analysis.

Results: The full mediation model showed a good fit to the data. However, chi-squared (χ(2)) tests for model comparison indicated that the partial mediation model better fits our data. Thus, the partial mediation model was used as the final model. In terms of auditory-verbal memory, the effect of aging on memory was fully mediated by executive function. However, visuo-spatial memory was significantly affected both indirectly (through executive function) and directly (by aging). Gender differences were not significant in this model.

Conclusion: This study demonstrated the importance of executive function in the memory functioning of normal aging adults. It is noteworthy that modality differences were found between auditory-verbal and visuo-spatial memory. Aging is not the only factor that drives memory decline, and its direct, adverse effect on memory was more prominent in the visuo-spatial memory task than auditory-verbal memory task. Since performance in both modalities is fully or partially mediated by executive function, it is important to train normal aging adults in executive control skills, such as planning, strategy formation, and rapid decision making.

No MeSH data available.


Related in: MedlinePlus