Is episodic memory change in aging associated with level of control processes and rate of control change? A 4-year longitudinal study

Using a longitudinal approach, we explored whether memory change over a 4-year period is associated with level of control at baseline and with change in control processes. Participants were evaluated twice with an interval of 4 years. Memory performance was assessed by a cued-recall test, and control processes by the Excluded Letter Fluency Test. We calculated an individual cognitive change index for each measure. Results indicated that both episodic memory and control processes declined significantly over time. Correlational analysis showed that memory change was significantly correlated with change in control processes but not with the level of control at baseline. Regression analysis indicated that 18% of the memory change variance could be explained by the change in control processes, consistent with the hypothesis that the level of memory change over time varies as a function of the rate of control change.