Background-. A better understanding is needed concerning the risk factors and markers of disease

Age-related differences in episodic memory have been explained by a decrement in strategic encoding implementation. It has been shown in clinical populations that music can be used during the encoding stage as a mnemonic strategy to learn verbal information. The effectiveness of this strategy remains equivocal in older adults (OA). Furthermore, the impact of the emotional valence of the music used has never been investigated in this context. Thirty OA and 24 young adults (YA) learned texts that were either set to music that was positively or negatively valenced, or spoken only. Immediate and delayed recalls were measured. Results showed that: (i) OA perform worse than YA in immediate and delayed recall; (ii) sung lyrics are better remembered than spoken ones in OA, but only when the associated music is positively-valenced; (iii) this pattern is observed regardless the retention delay. These findings support the benefit of a musical encoding on verbal learning in healthy OA and are consistent with the positivity effect classically reported in normal aging. Added to the potential applications in daily life, the results are discussed with respect to the theoretical hypotheses of the mechanisms underlying the advantage of musical encoding.

No abstract

Background Lack of awareness of cognitive decline (ACD) is common in late-stage Alzheimer’s disease (AD). Recent studies showed that ACD can also be reduced in the early stages. Methods We described different trends of evolution of ACD over 3 years in a cohort of memory-complainers and their association to amyloid burden and brain metabolism. We studied the impact of ACD at baseline on cognitive scores’ evolution and the association between longitudinal changes in ACD and in cognitive score. Results 76.8% of subjects constantly had an accurate ACD (reference class). 18.95% showed a steadily heightened ACD and were comparable to those with accurate ACD in terms of demographic characteristics and AD biomarkers. 4.25% constantly showed low ACD, had significantly higher amyloid burden than the reference class, and were mostly men. We found no overall effect of baseline ACD on cognitive scores’ evolution and no association between longitudinal changes in ACD and in cognitive scores. Conclusions ACD begins to decrease during the preclinical phase in a group of individuals, who are of great interest and need to be further characterized. Trial registration The present study was conducted as part of the INSIGHT-PreAD study. The identification number of INSIGHT-PreAD study (ID-RCB) is 2012-A01731-42.

Distinct classes of cognitive trajectories were associated with risk and protective factors of AD. These associations support the notion that the identified cognitive trajectories reflect different risk for AD that may be useful for selecting high-risk individuals for intervention trials.