Brain Stimulation for Memory Enhancement During Sleep Cycles

Overseen By Andreina Hampton

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of California, Los Angeles

Disqualifiers: Neurological, psychiatric issues, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: Unknown

Duration: 1-2 weeks

150 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to explore how memory functions and strengthens during sleep by using brain recordings and applying sound and electrical signals (a form of brain stimulation). The goal is to understand and potentially enhance memory by targeting specific brain activities during sleep. It is ideal for individuals with epilepsy who already have electrodes placed in their brains for medical reasons. Participants should be prepared to engage in the study and provide consent. As an unphased study, this trial offers a unique opportunity to contribute to groundbreaking research on memory enhancement.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What prior data suggests that this method is safe for memory enhancement during sleep?

Research shows that brain stimulation techniques, like those used in this trial, have been studied for their potential to improve memory, especially during sleep. Studies involving deep brain stimulation (DBS) in people with epilepsy have shown promise in affecting memory areas of the brain. These studies suggest that this type of stimulation is generally well-tolerated, with any side effects being minor or temporary.

Past research used electrical and sound stimulations to influence memory processing without causing significant side effects. However, each person's experience can differ. Overall, existing evidence supports the safe testing of these treatments in humans, but more research is needed to fully understand their safety. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it explores a cutting-edge method of enhancing memory by using brain stimulation during sleep cycles. Unlike current treatments for memory issues, which often focus on medication or cognitive therapy during waking hours, this technique targets the brain's natural processes during sleep. By decoding and selectively modulating human memory while asleep, this method could potentially boost memory retention more effectively and naturally. This approach offers a novel way to harness the brain's own rhythms to improve memory, which could lead to breakthroughs in treating memory-related conditions.

What evidence suggests that this method is effective for memory enhancement?

Research shows that boosting slow-wave brain activity during sleep can improve memory. One study found that people with mild memory problems who received this type of stimulation experienced better memory. Sleep already helps retain new memories, and reactivating memory paths in the brain during sleep supports this process. This trial explores how directly recording brain activity and using sound and electrical stimulation might further enhance memory. This approach aims to better understand and strengthen memory processes during sleep. ^{1 2 3 6 7}

Are You a Good Fit for This Trial?

This trial is for epilepsy patients aged 18-65 undergoing depth electrode placement. They must be willing to consent and participate, as determined by the epilepsy surgery team after neuropsychological and psychiatric evaluation. Those with additional neurological or psychiatric conditions posing risks are excluded.

Inclusion Criteria

Eligibility is determined by the epilepsy surgery team (based on neuropsychological testing and on psychiatric evaluation)

Willing to provide informed consent and participate in the study

Exclusion Criteria

Unwilling to provide informed consent

I have no major mental or neurological issues, except for epilepsy.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

Treatment

Participants undergo memory tasks and receive auditory and electrical stimulations during sleep to modulate memory processes

1-2 weeks

In-hospital stay

Follow-up

Participants are monitored for memory performance and neural activity post-treatment

1-2 days

What Are the Treatments Tested in This Trial?

Interventions

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

Trial Overview

The study aims to understand memory processes during sleep by recording brain activity in humans through various methods. It will also explore how auditory and electrical stimulations applied during sleep can affect memory consolidation.

Who Is Running the Clinical Trial?

University of California, Los Angeles

Lead Sponsor

Trials

1,594

Recruited

10,430,000+

National Institute of Neurological Disorders and Stroke (NINDS)

Collaborator

Trials

1,403

Recruited

655,000+

University of Iowa

Collaborator

Trials

486

Recruited

934,000+

Published Research Related to This Trial

A new protocol using surface cortical electrical stimulation during slow wave sleep (SWS) in a non-human primate showed that this stimulation can enhance learning of a neuroprosthetic task, indicating a potential method to improve memory consolidation.

The study highlights the importance of delta oscillatory activity during SWS in coordinating brain regions involved in memory, suggesting that targeted stimulation during this sleep phase could help understand and leverage synaptic plasticity for better learning outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cycle-Triggered Cortical Stimulation during Slow Wave Sleep Facilitates Learning a BMI Task: A Case Report in a Non-Human Primate. Rembado, I., Zanos, S., Fetz, EE.[2020]

In a study involving 25 healthy participants, the effectiveness of anodal transcranial direct current stimulation (so-tDCS) on memory retention was linked to specific brain activity patterns during baseline sleep, particularly the coupling of slow spindles with slow oscillation (SO) troughs.

The steepness and direction of the SO slope during baseline sleep were also predictive of how well participants retained declarative memories after stimulation, highlighting the importance of sleep dynamics in memory consolidation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Spontaneous slow oscillation-slow spindle features predict induced overnight memory retention. Dehnavi, F., Koo-Poeggel, PC., Ghorbani, M., et al.[2021]

Transcranial direct current stimulation applied during slow-wave sleep in 18 healthy participants increased slow-wave density and improved the coupling of fast spindles and slow-waves, which are important for memory consolidation.

However, while the stimulation enhanced sleep parameters, it did not improve overall memory retention and even impaired memory consolidation in participants with below-average pre-sleep performance, suggesting that enhancing sleep may not benefit those who struggle with memory the most.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Bi-Temporal Anodal Transcranial Direct Current Stimulation during Slow-Wave Sleep Boosts Slow-Wave Density but Not Memory Consolidation. Ruch, S., Fehér, K., Homan, S., et al.[2021]

Reactivating specific brain activity patterns during sleep can significantly improve memory performance the following day.

This finding suggests that sleep plays a crucial role in memory consolidation, highlighting the importance of sleep quality for learning and retention.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Let's replay. Rasch, B.[2020]

Transcranial electrical stimulation (tES) applied during sleep can enhance memory consolidation and improve metamemory sensitivity, which is our ability to judge the accuracy of our memories.

The study found that tES led to significant changes in brain network connectivity, particularly in the theta and spindle frequency bands, and these changes were linked to improvements in metamemory sensitivity, suggesting a mechanism for how tES can enhance memory processes during sleep.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Brain connectivity alterations during sleep by closed-loop transcranial neurostimulation predict metamemory sensitivity. Hubbard, RJ., Zadeh, I., Jones, AP., et al.[2021]

Real-time closed-loop deep brain stimulation during sleep, when synchronized with natural slow waves, significantly enhances sleep spindles and improves the coupling of brain activity, which is crucial for memory consolidation.

This synchronized stimulation not only boosts the accuracy of recognition memory but also shows a strong correlation between improved memory performance and enhanced brain electrophysiological activity, indicating a causal role in memory consolidation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Augmenting hippocampal-prefrontal neuronal synchrony during sleep enhances memory consolidation in humans. Geva-Sagiv, M., Mankin, EA., Eliashiv, D., et al.[2023]

In a study involving 26 elderly participants (average age 69.1 years), anodal transcranial direct current stimulation (tDCS) during early NREM sleep did not improve memory consolidation for either declarative or procedural tasks, contrasting with previous findings in younger adults.

The tDCS was associated with increased wakefulness and reduced deep sleep (NREM stage 3), suggesting that the stimulation may disrupt rather than enhance sleep-dependent memory processes in older individuals.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

No effects of slow oscillatory transcranial direct current stimulation (tDCS) on sleep-dependent memory consolidation in healthy elderly subjects. Eggert, T., Dorn, H., Sauter, C., et al.[2016]

Short duration repetitive transcranial electrical stimulation (SDR-tES) during daytime naps significantly enhances declarative memory consolidation in healthy individuals, showing improved memory performance compared to sham stimulation both immediately after sleep and 48 hours later.

SDR-tES also increases the amount of time spent in deeper NREM sleep (NREM3) and boosts the rate of slow oscillations during NREM sleep, suggesting that the timing of stimulation during quiet brain activity may optimize its effects on memory consolidation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Short Duration Repetitive Transcranial Electrical Stimulation During Sleep Enhances Declarative Memory of Facts. Cellini, N., Shimizu, RE., Connolly, PM., et al.[2023]

The study demonstrated that closed-loop transcranial Alternating Current Stimulation (tACS) during sleep can enhance memory consolidation, specifically improving the ability to generalize learned information, as shown by better performance on a target detection task in 21 participants.

An interesting finding was the inverted U-shaped dose effect of tACS on slow-wave oscillations, suggesting that the timing and intensity of stimulation are crucial for optimizing memory benefits, highlighting the potential of this method for both healthy individuals and those with neuropsychiatric conditions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dose-Dependent Effects of Closed-Loop tACS Delivered During Slow-Wave Oscillations on Memory Consolidation. Jones, AP., Choe, J., Bryant, NB., et al.[2020]

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