Serial position effects in the Logical Memory Test: Loss of primacy predicts amyloid positivity

Abstract

Background Story recall is a frequently used neuropsychological test of episodic memory with clinical populations and for screening participants in drug trials for Alzheimer’s disease. However, it is unclear at this stage which underlying mechanisms confer the test its sensitivity. In this paper, we examined serial position effects, that is, better recall for items learned early and late on a list, in story recall, and their usefulness to predict early changes associated with neurodegenerative markers. Methods We analysed data from the Wisconsin Registry for Alzheimer’s Prevention. First, we tested whether serial position effects were present in story recall (measured with the Wechsler Memory Scale Logical Memory Task; LMT) across individuals who were classified as cognitively unimpaired – stable, cognitively unimpaired – declining, or as having mild cognitive impairment (MCI). Results Our results showed clear serial position effects for all groups, except for delayed recall among individuals with MCI, where no primacy effect was observed. Second, we tested whether loss of primacy from immediate to delayed recall was associated with amyloid burden (as measured with PiB PET) in individuals who were cognitively unimpaired at baseline. We found that more primacy loss predicted amyloid positivity, above and beyond the LMT total score. Conclusions This report is the first to show that loss of primacy between immediate and delayed story recall is associated with amyloid burden.

Cross-sectional associations of CSF tau levels with Rey’s AVLT: A recency ratio study.

“…To note, unlike total and delayed recall, Rr takes into consideration loss of information from immediate to delayed recall, as it tracks a difference between performances, and hence may be more attuned to neurodegenerative damage. Consistent with this idea is the previous finding that Rr was sensitive to CSF neurogranin levels, a biomarker of postsynaptic dysfunction and possible neurodegeneration, in cognitively intact older individuals with major depression (Bruno, Mueller, et al, 2021; Bruno, Reichert Plaska, et al, 2021).…”

“…Relatedly, cognitive tests are relatively unintrusive, thus facilitating data collection on participants who are averse to medical procedures. Second, because subtle neuropsychological changes can be observed already when individuals with elevated levels of AD biomarkers are still asymptomatic for the disease (e.g., Bruno, Mueller, et al, 2021; Mueller et al, 2020).…”

Time is of the essence: Exploring temporal and spatial organisation in episodic memory

“…However, recent reports have suggested rehearsal may not be sufficient to explain primacy effects in short lists ( Grenfell-Essam et al, 2013 ; Spurgeon et al, 2014 ). Excluding rehearsal, then a possible explanation of our results, also previously presented in Bruno et al (2016 , 2020) , relies upon a combination of memorability and attributional cueing. Once the most memorable item is retrieved (i.e., often the first and most distinctive perhaps due to increased attentional focus on that item ( Sederberg et al, 2006 ), so-called “edge effects” ( Brown et al, 2007 ), or greater availability of processing resources ( Tulving, 2008 )), it is then possible that features of this item, such as temporal and/or spatial cues, will facilitate retrieval of other items and therefore influence the sequence of recall.…”

Validation of a remote and fully automated story recall task to assess for early cognitive impairment in older adults: a longitudinal case-control observational study

“…Speech responses are a common component of cognitive tests, however data generated in these tests, including those reported in this study, often relate to simple pass/fail characteristics of response accuracy. New metrics using audio-and text-based AI models to target other changes measurable in speech data (acoustic [30,31], semantic [32][33][34][35], linguistic [31]) in early-stage Alzheimer's disease could further leverage the information content of ASRTs, developing a new class of powerful, fully automated speech biomarkers.…”