Specific, personally meaningful cues can benefit episodic prospection in medial temporal lobe amnesia

Abstract

Objectives To determine whether severity of episodic prospection impairment in medial temporal lobe (MTL) amnesia is reduced by the types of cues that are used to elicit personal future episodes and, if so, whether episodic memory impairment is similarly affected. Design Multiple case study of five individuals with MTL amnesia and healthy control participants. Methods Participants were administered two tests of episodic prospection: A commonly used Galton-Crovitz task that uses generic cues (e.g., lemon) and a novel task that includes specific, personally meaningful cues referring to planned or plausible future events (e.g., granddaughter's recital). Narratives were scored for episodic detail using the Autobiographical Interview protocol (Levine et al., 2002), which distinguishes between internal (episodic) details and external (non-episodic) details. Results Results showed that specific, personally meaningful cues led to an appreciable reduction of episodic memory and prospection impairment in three of the amnesic cases tested. Clinical benefit from more structured, self-related cues may depend on factors such as extent of MTL damage or general severity of episodic memory and prospection impairment, highlighting the importance of methodological approaches to neuropsychological research that treat each case on an individual basis. Conclusions In cases of mild-moderate amnesia, specific, personal cues afford more detailed episodic remembering and prospective imagining than individual cue words. Practitioner points Previous reports of episodic prospection impairment in medial temporal lobe (MTL) amnesia might misrepresent an individual case's true prospective abilities Specific cues drawn from a patient's everyday life have greater ecological validity than the more typical generic cues used to elicit episodic prospection and can aid some individuals with MTL amnesia in the ability to imagine future experiences Assessment and rehabilitation tools for MTL amnesic populations should attempt to minimize broad, open-ended questions and instead provide more structured and personally meaningful cues to guide responses Further research is needed to determine case-specific characteristics that best predict benefit from specific, personal cues. These might include extent of MTL damage and overall severity of episodic memory and prospection impairment.