F047 Characterization of interference effect on the LASSI-L verbal learning test in premanifest Huntington’s disease

<h3>Background</h3> Cognitive deficits frequently precede motor manifestations in premanifest Huntington’s disease (preHD). Previous studies in preHD have reported early and significant Proactive Semantic Interference (PSI), leading to worsened memory performance. Further characterization of the interference in preHD, including the source of intrusions and whether they are exacerbated by cueing, remains important. <h3>Aims</h3> This study assessed semantic interference in preHD versus controls (HC) by comparing types of intrusion errors on the Loewenstein-Acevedo Scales of Semantic Interference and Learning (LASSI-L). Source errors were categorized as Competing List Intrusions (CLI), Semantically Related Intrusions (SRI), and Unrelated Intrusions (UI). <h3>Methods</h3> LASSI-L was administered to 29 preHD participants and 25 HC, matched for age/education. Free and cued recall trials were compared between groups using Mann-Whitney U; intrusion types within groups were compared using the signed-rank test. Raw intrusions were normed by total responses on each section. <h3>Results</h3> PreHD had more CLIs during cued B1 recall (PSI) (p = 0.0173), cued B2 recall (p = 0.0124), and free recall A3 (p = 0.0404). Both preHD and HC had more CLIs than SRIs on A3 cued recall (p = 0.0031; p = 0.0008). Both groups committed more intrusions on cued versus free recall sections, and recorded few SRIs and no UIs. <h3>Conclusion</h3> The study highlights the significant challenge that preHD individuals face in managing semantically-related memory interference, as evidenced by increased Competing List Intrusions (CLIs) during cued recall tasks. These findings underscore the potential benefit of incorporating cueing and semantically competing lists in the design of verbal learning tasks in preHD.