Investigating the impact of digital memory augmentation on accelerated long-term forgetting of autobiographical memory and psychological well-being in patients with transient epileptic amnesia

<h3></h3> Accelerated long-term forgetting (ALF) is the abnormally rapid fading of memories in the days and weeks following memory encoding. This memory impairment is particularly high in patients with Transient Epileptic Amnesia (TEA), a subtype of temporal lobe epilepsy characterised by recurrent amnestic seizures and interictal autobiographical memory deficits such as ALF. We used a smartphone-based intervention, HippoCamera, to investigate the effects of digital memory augmentation on the recall of memories, assessed at a 2.5-week delay using the Autobiographical Interview. With HippoCamera, users record visual and auditory cues of events they wish to remember. HippoCamera then curates personalised replay sessions of previously recorded cues, played to users at an increased speed, to mimic temporal compression in the hippocampus. In this study, patients and healthy controls recorded daily cues for three weeks. Cues were assigned to either a ‘replayed’ condition, where they were replayed throughout the study, or a ‘hidden’ condition, where they were never replayed. During recall, patients provided significantly more episodic details for replayed than hidden memories (z=-3.254, p=0.0011). Specifically, recollection of event details (z=-2.891, p=0.0038), time details (z=-2.194, p=0.0282) and thought or emotion details increased (z=-2.114, p=0.0346). Additionally, patients rated replayed memories as more vivid (t= -3.694, p=0.0003) and accessible (t= -4.763, p&lt;.0001) than hidden memories. For both patients and healthy controls, scores on the Tennesee Self-Concept Scale significantly increased after using HippoCamera for the duration of the study (t=6.177, p=0.0001 and t=5.027, p=0.0003, respectively). The results suggest that in patients, HippoCamera improves recall of episodic details of autobiographical memories, with specific emphasis on event, time, and thought or emotion details. Furthermore, HippoCamera use in both patients and controls improves psychological well-being related to positive self-perceptions of identity, self-satisfaction and behaviour. This study is the first autobiographical memory intervention in TEA and demonstrates the benefit of HippoCamera use for autobiographical memory deficits, such as ALF, and psychological well-being.