Sleep and Rehearsal-Driven Memory in Epilepsy

NCT06967935 | Recruiting

• 2 other identifiers: 69HCL25_01882025-A00510-49
• Study Type: observational
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Memory consolidation transforms unstable memory traces into lasting representations, a process enhanced by both sleep and rehearsal during learning. Rehearsal is thought to accelerate consolidation by inducing memory reactivations that resemble those occurring during sleep. However, the respective mechanisms of sleep- and rehearsal-induced consolidation-and their potential interactions-remain poorly understood, especially in patients with temporal lobe epilepsy, where rehearsal might help compensate for memory deficits linked to hippocampal dysfunction, and where sleep may exacerbate epileptic activity. The CORESOM-EPI study aims to compare the effects of rehearsal and sleep on memory consolidation in patients undergoing video-EEG monitoring. Participants will learn "object-place" associations under two conditions (single versus repeated encoding), with memory tested immediately and again after a 12-hour delay. This delay will either include a full day awake or a night of sleep, allowing direct comparison of sleep- and rehearsal-related consolidation effects. Each participant will perform the task twice, with "wake" and "sleep" condition, in a balanced order. As a preliminary phase of the CRIMES study (ANR-DFG 2024), CORESOM-EPI will help assess how sleep and rehearsal influence memory consolidation in epilepsy. It will also serve to adapt the behavioral task for clinical use, paving the way for a future intracranial EEG investigations that will explore the neural networks involved and their modulation by epileptic activity.

Conditions

Epilepsy; Memory Consolidation

Keywords

Epilepsy; Memory consolidation; Sleep; Reharsal; Reactivation

Outcome Measures

Primary Outcomes (4)

• Change in the percentage of object categories recalled (vs. not recalled) between immediate (30 min after learning) and delayed (12h after learning) recall for rehearsed versus non-rehearsed items.

  The impact of rehearsal on object category recognition in an object-place learning paradigm is assessed. For the primary outcome, data from the 2 conditions ("wake" and "sleep" during the 12h period between immediate and delayed recall) will be pooled. Each participant will take part in the wake and sleep condition over 4 days (2 conditions separated by at least 24h), in a balanced order between participants.

  Day 2

• Change in the percentage of object categories recalled (vs. not recalled) between immediate (30 min after learning) and delayed (12h after learning) recall for rehearsed versus non-rehearsed items.

  The impact of rehearsal on object category recognition in an object-place learning paradigm is assessed. For the primary outcome, data from the 2 conditions ("wake" and "sleep" during the 12h period between immediate and delayed recall) will be pooled. Each participant will take part in the wake and sleep condition over 4 days (2 conditions separated by at least 24h), in a balanced order between participants.

  Day 2 + 12 hours

• Change in the percentage of object categories recalled (vs. not recalled) between immediate (30 min after learning) and delayed (12h after learning) recall for rehearsed versus non-rehearsed items.

  The impact of rehearsal on object category recognition in an object-place learning paradigm is assessed. For the primary outcome, data from the 2 conditions ("wake" and "sleep" during the 12h period between immediate and delayed recall) will be pooled. Each participant will take part in the wake and sleep condition over 4 days (2 conditions separated by at least 24h), in a balanced order between participants.

  Day 2 + 36 hours

• Change in the percentage of object categories recalled (vs. not recalled) between immediate (30 min after learning) and delayed (12h after learning) recall for rehearsed versus non-rehearsed items.

  The impact of rehearsal on object category recognition in an object-place learning paradigm is assessed. For the primary outcome, data from the 2 conditions ("wake" and "sleep" during the 12h period between immediate and delayed recall) will be pooled. Each participant will take part in the wake and sleep condition over 4 days (2 conditions separated by at least 24h), in a balanced order between participants.

  Day 2 + 48 hours

Study Arms (2)

WAKE - SLEEP

This group will start with the condition 1 " wake " (encoding+immediate recall in the morning (8 :00am) and delayed recall in the evening (8 :00pm)) and will end with the condition 2 " sleep " : (encoding+immediate recall in the evening (8 :00pm) and delayed recall in the morning (8 :00am))

Other: Cognitive memory task on a computer; Other: Eye tracking; Other: Questionnaires on task-related fatigue; Other: Questionnaire on task difficulty; Other: Karolinska scale

SLEEP-WAKE

This group will start with the condition 2 " sleep "and will end with the condition 1 " wake "

Other: Cognitive memory task on a computer; Other: Eye tracking; Other: Questionnaires on task-related fatigue; Other: Questionnaire on task difficulty; Other: Karolinska scale

Interventions

Cognitive memory task on a computer OTHER

Encoding: (1) Participants will learn 60 associations between pairs of items (cue and target) that are presented sequentially at unique locations on a screen, in a given context. 30 pairs are presented once, and 30 pairs are presented repeatedly (4 times). (2) After learning, the first recall phase begins after a short delay of 30 minutes: 50% of the pairs are tested in a similar way, this time with an assessment of contextual memory. (3) The remaining 50% of pairs are tested after a 12-hour delay, involving either a day awake (condition 1) or a night asleep (condition 2).

SLEEP-WAKE; WAKE - SLEEP

Eye tracking OTHER

Eye-tracking will be carried out during the task to ensure that participants are focused on the task (quantification of the number and duration of eye fixations in the area of interest corresponding to the target presentation)

SLEEP-WAKE; WAKE - SLEEP

Questionnaires on task-related fatigue OTHER

Questionnaire on task-related fatigue (Likert-scale) will be completed by participants between blocks of items during the task

SLEEP-WAKE; WAKE - SLEEP

Questionnaire on task difficulty OTHER

Questionnaires on task difficulty (Likert-scale) will be completed by participants at the end of the task

SLEEP-WAKE; WAKE - SLEEP

Karolinska scale OTHER

Participants' state of sleepiness will be assessed at the beginning of each stage (encoding, immediate recall, delayed recall) using the Karolinska sleepiness scale

SLEEP-WAKE; WAKE - SLEEP

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients with epilepsy admitted to the Functional Neurology and Epileptology Department of the Hospices Civils de Lyon (University Hospital) for video-EEG monitoring will be invited by the investigating physician to participate in the study. If patients wish to take part, they will be asked to perform a cognitive task.

You may qualify if:

• Patient with epilepsy (any type of epilepsy)
• Hospitalized for video-EEG recording lasting at least 4 days
• Aged 18-65 years

You may not qualify if:

• Major cognitive impairment other than memory deficit
• Refusal to participate
• Pregnant women, women in labor or nursing mothers
• Persons deprived of their liberty by judicial or administrative decision
• Persons under psychiatric care
• Persons admitted to a health or social institution for purposes other than research
• Adults under legal protection (guardianship, curatorship)

Sponsors & Collaborators

• Hospices Civils de Lyon: lead

Study Sites (1)

Service de neurologie fonctionnelle et d'épileptologie, Hôpital neurologique Pierre Wertheimer

Bron, 69500, France

RECRUITING

MeSH Terms

Conditions

Epilepsy

Condition Hierarchy (Ancestors)

Brain Diseases; Central Nervous System Diseases; Nervous System Diseases

Central Study Contacts

Laure PETER-DEREX, Professor

CONTACT

+334 72 07 17 69; laure.peter-derex@chu-lyon.fr

Sylvain Rheims, Professor

CONTACT

+334 72 45 79 00; sylvain.rheims@chu-lyon.fr

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 5, 2025
• First Posted: May 13, 2025
• Study Start: June 30, 2025
• Primary Completion (Estimated): July 1, 2026
• Study Completion (Estimated): July 1, 2026
• Last Updated: July 8, 2025

Record last verified: 2025-07

Locations

FR (1)