title: Higher intraindividual variability is associated with more forgetting and dedifferentiated memory functions in old age.
abstract: Intraindividual trial-to-trial reaction time (RT) variability is commonly found to be higher in clinical populations or life periods that are associated with impaired cognition. In the present study, higher within-person trial-to-trial RT variability in a perceptual speed task is related to more forgetting and dedifferentiation of memory functions in older adults (aged 60-71 years). More specifically, our study showed that individuals in a high-variability group (n=175) forgot more memory scenes over a 1-week retention interval than individuals in the low-variability group (n=174). In contrast, slower RT speed was associated with poorer episodic memory in general, but unrelated to the amount of forgetting. Moreover, results from multiple group latent factor analyses showed that episodic memory and working memory functions were more highly correlated in the high-variability (r=.63) than in the low-variability (r=.25) group. Given that deficits in dopamine (DA) modulation may underlie increases in RT variability, the present findings are in line with (i) recent animal studies implicating DA in long-term episodic memory consolidation and (ii) neurocomputational work linking DA modulation of performance variability to dedifferentiation of cognitive functions in old age.
authors: Max Planck Institute for Human Development, D-14195 Berlin, Germany. papenberg@mpib-berlin.mpg.de
authors: Goran
authors: G
authors: Papenberg
authors: Lars
authors: L
authors: Bäckman
authors: Christian
authors: C
authors: Chicherio
authors: Irene E
authors: IE
authors: Nagel
authors: Hauke R
authors: HR
authors: Heekeren
authors: Ulman
authors: U
authors: Lindenberger
authors: Shu-Chen
authors: SC
authors: Li
mesh_terms: D000368:Aged / Q000523:psychology*; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D003071:Cognition / Q000502:physiology; D003198:Computer Simulation; D004298:Dopamine / Q000502:physiology; D056344:Executive Function / Q000502:physiology; D005260:Female; D006801:Humans; D007206:Individuality; D008297:Male; D008568:Memory / Q000502:physiology*; D008569:Memory Disorders / Q000523:psychology*; D008570:Memory, Short-Term / Q000502:physiology; D011939:Mental Recall / Q000502:physiology; D008875:Middle Aged; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D011954:Receptors, Dopamine / Q000378:metabolism / Q000502:physiology; D013028:Space Perception / Q000502:physiology; D014796:Visual Perception / Q000502:physiology
chemical_list: D011954:Receptors, Dopamine; D004298:Dopamine