NCT06938672

Brief Summary

The goal of this interventional study is to learn if transcranial direct current stimulation (tDCS), a gentle, cost-effective and non-invasive brain stimulation technique can improve sleep brain activity during an afternoon nap. Since these sleep brain patterns are linked to better memory, attention, and thinking skills, this study aims to find out if improving sleep in a nap can also enhance these cognitive skills in healthy older adults (aged 60+). The main questions it aims to answer are:

  • Can a short (20-minute) tDCS session before a nap improve sleep patterns during the nap?
  • Since these sleep patterns are linked to memory and attention, can tDCS also improve thinking skills after the nap?
  • Are two tDCS session more effective than one for improving nap sleep and thinking skills? Participants will:
  • Be required to come to the university for testing over four days. During each session they will:
  • Complete computer based-tasks to assess memory and thinking.
  • Receive a 20-minute session of either real (active) or fake (placebo) tDCS.
  • Take a short, monitored nap while researchers measure sleep activity (using polysomnography - a gold-standard, non-invasive sleep monitoring tool).
  • Complete an easy-to-use sleep test at home on the nights after the naps.
  • Wear a lightweight watch (called an Actiwatch) throughout the study period to track sleep and movement.
  • Complete daily sleep diaries. By taking part, participants will help researchers understand whether tDCS can improve sleep during naps and, in turn, support memory and thinking skills. This research could lead to better treatments for sleep problems, help protect brain health, and reduce the risk of dementia as people age. The brain stimulation in this study may also help improve their sleep and cognition.

Trial Health

57
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
23

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Jul 2025

Shorter than P25 for not_applicable

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

March 13, 2025

Completed
1 month until next milestone

First Posted

Study publicly available on registry

April 22, 2025

Completed
2 months until next milestone

Study Start

First participant enrolled

July 1, 2025

Completed
4 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

October 31, 2025

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

October 31, 2025

Completed
Last Updated

July 4, 2025

Status Verified

July 1, 2025

Enrollment Period

4 months

First QC Date

March 13, 2025

Last Update Submit

July 1, 2025

Conditions

Keywords

sleephealthy agingcognitiontDCSnon-invasive brain stimulationnap

Outcome Measures

Primary Outcomes (7)

  • Sleep spindle density

    PSG-measured slow (11.99 - 12.99Hz) and fast (13 - 14.99Hz) sleep spindle density

    During nap immediately after tDCS application

  • Sleep spindle amplitude

    PSG-measured slow (11.99 - 12.99Hz) and fast (13 - 14.99Hz) sleep spindle amplitude

    During nap immediately after tDCS application

  • Slow wave sleep amplitude

    PSG-measured SWS amplitude (peak-to-peak, μV)

    During nap immediately after tDCS application

  • Slow wave sleep density

    PSG-measured slow wave sleep density (number of slow waves divided by the minutes of sleep)

    During nap immediately after tDCS application

  • Verbal declarative memory

    Change in Verbal Paired Associates Word Learning Task performance will be measured by % correct recall at baseline (before the tDCS intervention and nap) compared to % correct recall 15 minutes after the nap has taken place.

    Baseline (before tDCS/nap) and 15 minutes after the nap

  • Attentional Network Task (ANT)

    Change in Attentional Network Task performance will be measured by Reaction Time (RT) (Milliseconds (ms) at baseline (before the tDCS intervention and nap) compared to RT (ms) 15 minutes after the nap has taken place.

    Baseline (before tDCS/nap) and 15 minutes after the nap

  • Attentional Network Task (ANT)

    Change in Attentional Network Task performance will be measured by Accuracy (%) at baseline (before the tDCS intervention and nap) compared to Accuracy (%) 15 minutes after the nap has taken place.

    Baseline (before tDCS/nap) and 15 minutes after the nap

Secondary Outcomes (2)

  • Visuo-spatial declarative picture memory

    Baseline (before tDCS/nap) and 15 minutes after the nap

  • Visuo-spatial declarative location memory

    Baseline (before tDCS/nap) and 15 minutes after the nap

Study Arms (2)

Active Transcranial Direct Current Stimulation (tDCS)

ACTIVE COMPARATOR

Transcranial direct current stimulation. Participants will experience a 20-minute session of active tDCS (1.2 mA) on two consecutive days.

Device: Active Transcranial Direct Current Stimulation (tDCS)

Placebo Transcranial Direct Current Stimulation (tDCS)

PLACEBO COMPARATOR

Transcranial direct current stimulation. Participants will experience a 20-minute session of placebo tDCS on two consecutive days.

Device: Placebo Transcranial Direct Current Stimulation (tDCS)

Interventions

Placebo Transcranial direct current stimulation (tDCS): Participants will experience a 20-minute session of placebo tDCS on two consecutive days.

Also known as: sham tDCS
Placebo Transcranial Direct Current Stimulation (tDCS)

Active transcranial direct current stimulation (tDCS). Participants will experience a 20-minute session of active tDCS (1.2 mA) on two consecutive days.

Also known as: tDCS
Active Transcranial Direct Current Stimulation (tDCS)

Eligibility Criteria

Age60 Years+
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Aged 60+ years
  • Speak fluent English
  • Be cognitively healthy
  • A self-reported good sleeper, with a regular sleep pattern

You may not qualify if:

  • The presence of any major physical or psychiatric illness or comorbidities
  • Self-reported neurodegenerative dementia or other neurological disorders
  • Self-reported relevant sleep disorders or disturbances
  • Those with irregular sleep schedules (i.e. night shift workers)
  • A PSQI score above 5 (as this is associated with significant sleep disturbance)
  • Relevant skin allergies
  • Taking medication that affects the central nervous system or sleep, or consume caffeine, alcohol or cigarettes excessively
  • Metallic or electronic implants

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Northumbria University

Newcastle upon Tyne, NE1 8ST, United Kingdom

RECRUITING

MeSH Terms

Interventions

Transcranial Direct Current Stimulation

Intervention Hierarchy (Ancestors)

Electric Stimulation TherapyTherapeuticsConvulsive TherapyPsychiatric Somatic TherapiesBehavioral Disciplines and ActivitiesElectroshockPsychological Techniques

Study Officials

  • Rosie H Musgrave, BA Hons, RPSGT

    Northumbria University

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, INVESTIGATOR
Purpose
PREVENTION
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

March 13, 2025

First Posted

April 22, 2025

Study Start

July 1, 2025

Primary Completion

October 31, 2025

Study Completion

October 31, 2025

Last Updated

July 4, 2025

Record last verified: 2025-07

Data Sharing

IPD Sharing
Will not share

Locations