Decoding and Selective Modulation of Human Memory During Awake/Sleep Cycles

The proposed project seeks to elucidate memory processes and consolidation during sleep by leveraging the unique capability of direct recordings from the human brain at multiple levels of resolution-single neurons, localized neuronal assemblies, intracranial local field potentials-during rich behavioral tasks with real-life narratives and extracting neural features that relate to different aspects of episodic experience. The investigators will further probe causal mechanisms of consolidation by application of auditory and electrical stimulations during sleep and its effect on modulating memory processes.

Study Overview

• Status: Recruiting
• Conditions: Memory, Delayed
• Intervention / Treatment: Other: Auditory and Electrical Stimulation

• Study Type: Interventional
• Enrollment (Estimated): 150
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Andreina Hampton; Phone Number: 3236105293; Email: amhampton@mednet.ucla.edu

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90095
      • Recruiting
      • University of California Los Angeles
      • Contact: Andreina Hampton; Phone Number: 3236105293; Email: amhampton@mednet.ucla.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• All epilepsy patients between the ages of 18 and 65 who undergo depth electrode placement for clinical purposes
• Eligibility is determined by the epilepsy surgery team (based on neuropsychological testing and on psychiatric evaluation)
• Willing to provide informed consent and participate the study

Exclusion Criteria:

• Neurological or psychiatric issues, other than epilepsy, that would put the patient at risk
• Patient is younger than 18 or older than 65 years of age
• Unwilling to provide informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: Single

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Recognition Accuracy	Accuracy will be analyzed to evaluate performance on memory tasks before and after sleep, specifically the ability to recognize correct items compared to all items. Accuracy will be measured using the sum of true positive and true negative divided by the total number of items. A within-subjects design will be employed and accuracy for stimulated vs. non-stimulated items will be compared.	1-2 days contained within the participants' 1-2 week hospital stay; Specifically for each experiment, the outcome measure will be computed during the pre- and post-sleep memory tasks
Recognition Discriminability (D-prime)	Discriminability will be analyzed to evaluate performance on memory tasks before and after sleep, specifically the ability to recognize target items from distractor items. Discriminability will be measured using a discriminability index (d-prime). In addition to d-prime being a normalized metric, it provides critical and complementary information to the accuracy metric (Outcome 1) given that it is a measure of sensitivity (and not bias) in the cases where data labels are not balanced . A within-subjects design will be employed and discriminability for stimulated vs. non-stimulated items will be compared.	1-2 days contained within the participants' 1-2 week hospital stay; Specifically for each experiment, the outcome measure will be computed during the pre- and post-sleep memory tasks.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Power sleep oscillations	The power of slow waves, spindles, ripples (all in units of dbm) will be computed. Employing a within-subjects design, the investigators will compare the change in the power of these oscillatory features for stimulated vs. non-stimulated items.	1-2 days contained within the participants' 1-2 week hospital stay. Specifically for each experiment, the outcome measure will be computed during the sleep period between pre and post-sleep memory tasks.
Neuronal replay index	Neuronal replay index, defined as the percentage of time during which neurons manifest replay-like activation as compared to the duration of deep sleep will be computed. Employing a within-subjects design, the investigators will compare the replay measure for stimulated vs. non-stimulated items.	1-2 days contained within the participants' 1-2 week hospital stay. Specifically for each experiment, the outcome measure will be computed during the sleep period between pre and post-sleep memory tasks.

Collaborators and Investigators

• Sponsor: University of California, Los Angeles
• Collaborators: National Institute of Neurological Disorders and Stroke (NINDS); University of Iowa

Study record dates

Study Major Dates

• Study Start (Actual): July 13, 2022
• Primary Completion (Estimated): August 31, 2026
• Study Completion (Estimated): August 31, 2026

Study Registration Dates

• First Submitted: June 18, 2022
• First Submitted That Met QC Criteria: July 6, 2022
• First Posted (Actual): July 11, 2022

Study Record Updates

• Last Update Posted (Estimated): October 14, 2025
• Last Update Submitted That Met QC Criteria: October 9, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Keywords: memory; sleep; stimulation; learning; single-unit
• Additional Relevant MeSH Terms: Investigative Techniques; Physical Stimulation; Electric Stimulation
• Other Study ID Numbers: U01NS123128 (U.S. NIH Grant/Contract); 1U01NS123128-01 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The investigators will make data available in accordance with the latest BRAIN Initiative Data Sharing Plan. The data consists of intracranial recordings from human epilepsy patients while participants perform a cognitive task during awake periods and follow-up recordings during overnight sleep or nap sessions. These datasets will be shared in a HIPAA-compliant manner (anonymized and coded) and will not include any sensitive information such as Protected Health Information. The investigators plan to deposit the data using the NIH Data Archive Brain Initiative platform, specialized at storage and organization of invasive neurophysiology data.
• IPD Sharing Time Frame: All data will be provided by the time publication occurs or per NIH latest policies for the data to be shared periodically via specialized storage for invasive neurophysiology data.
• IPD Sharing Access Criteria: Researchers can request access to the data under collaborative and co-authorship agreements prior to the end of the funding period or before publication.
• IPD Sharing Supporting Information Type: ANALYTIC_CODE

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No