Supporting Episodic Memory With Transcranial Direct Current Stimulation in Healthy Controls and Dementia Patients

NCT03227185 | Terminated

• 2 other identifiers: 33512016-02175
• Study Type: interventional
• Target: 55
• Locations: 1 country
• Sites: 1

Brief Summary

Previous studies showed that anodal tDCS applied over the dorsolateral prefrontal cortex (DLPFC) improved episodic memory performance, indicating a possible use as an intervention for patients suffering from memory impairments. At the same time, only scant evidence (provided by functional magnetic resonance imaging (fMRI) and magnetic resonance spectroscopy (MRS)) exists regarding the underlying mechanisms, thus hindering a more targeted application. The present study aims at establishing a connection between the stimulation-induced change in episodic memory performance on the behavioural level and neurophysiological parameters. TDCS effects and the underlying mechanisms will be compared between different study conditions, receiving either real anodal tDCS or sham stimulation over the left dorsolateral prefrontal cortex during an episodic memory task.

Conditions

Healthy; Mild Cognitive Impairment; Alzheimer Disease

Outcome Measures

Primary Outcomes (3)

• Episodic memory performance - learning curve

  Number of encoded words during the three consecutive immediate retrievals in the encoding phase

  0.25 hours

• Episodic memory performance - delayed recall 1

  Number of remembered words in the delayed recall after a short delay at the day of the on-site visit

  20 min after encoding phase

• Episodic memory performance - delayed recall 2

  Number of remembered words one day after learning

  1 day after on-site visit

Secondary Outcomes (1)

• Neurotransmitter levels

  0.5 hours

Study Arms (2)

Real - sham anodal tDCS

EXPERIMENTAL

Session 1: 20 min of 1 mA anodal tDCS applied via 5x7 cm rubber electrodes over the DLPFC (current density: 0.028 mA/cm2). Additional ramp-up and ramp-down phase at beginning and end of stimulation lasting for 15 s. Electrodes remain attached to the participant's head for the duration of the encoding phase. Session 2: 30 s of 1 mA anodal tDCS applied via 5x7 cm rubber electrodes over the DLPFC (current density: 0.028 mA/cm2). Additional ramp-up and ramp-down phase at beginning and end of stimulation lasting for 15 s. Electrodes remain attached to the participant's head for the duration of the encoding phase.

Device: real anodal transcranial direct current stimulation (tDCS); Device: sham transcranial direct current stimulation (tDCS)

Sham - real anodal tDCS

EXPERIMENTAL

Session 1: 30 s of 1 mA anodal tDCS applied via 5x7 cm rubber electrodes over the DLPFC (current density: 0.028 mA/cm2). Additional ramp-up and ramp-down phase at beginning and end of stimulation lasting for 15 s. Electrodes remain attached to the participant's head for the duration of the encoding phase. Session 2: 20 min of 1 mA anodal tDCS applied via 5x7 cm rubber electrodes over the DLPFC (current density: 0.028 mA/cm2). Additional ramp-up and ramp-down phase at beginning and end of stimulation lasting for 15 s. Electrodes remain attached to the participant's head for the duration of the encoding phase.

Device: real anodal transcranial direct current stimulation (tDCS); Device: sham transcranial direct current stimulation (tDCS)

Interventions

real anodal transcranial direct current stimulation (tDCS) DEVICE

The MR-compatible neuroConn DC-Stimulator MR (neuroCare Group, Ilmenau, Germany) will be used in the study.

Real - sham anodal tDCS; Sham - real anodal tDCS

sham transcranial direct current stimulation (tDCS) DEVICE

The MR-compatible neuroConn DC-Stimulator MR (neuroCare Group, Ilmenau, Germany) will be used in the study.

Real - sham anodal tDCS; Sham - real anodal tDCS

Eligibility Criteria

• Age: 20 Years - 85 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Written informed consent
• Right-handedness
• Non-smokers
• Native German speakers or comparable level of fluency
• Normal or corrected-to-normal vision

You may not qualify if:

• Neurological or psychiatric condition (other than diagnosed cognitive impairment)
• Past head injuries
• Magnetizable implants
• History of seizures
• Current or life-time alcohol or drug abuse
• Pregnancy
• Skin diseases

Sponsors & Collaborators

• University of Bern: lead

Study Sites (1)

University Hospital of Old Age Psychiatry and Psychotherapy

Bern, 3000, Switzerland

Location

MeSH Terms

Conditions

Cognitive Dysfunction; Alzheimer Disease

Condition Hierarchy (Ancestors)

Cognition Disorders; Neurocognitive Disorders; Mental Disorders; Dementia; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Tauopathies; Neurodegenerative Diseases

Study Officials

• Stefan Klöppel, Prof

  University Hospital of Old Age Psychiatry and Psychotherapy

  PRINCIPAL INVESTIGATOR

Study Design

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

Model Details: Participants will be randomly assigned to two possible sequences of stimulation conditions. Group 1 will receive real tDCS stimulation to the left dlPFC during encoding on the first day and sham stimulation on the second day, and group 2 will receive sham stimulation during encoding on the first day and real tDCS on the second day. The participants will be randomized with equal probability to each of the two groups, using block randomization..

Study Record Dates

• First Submitted: July 19, 2017
• First Posted: July 24, 2017
• Study Start: October 1, 2017
• Primary Completion: October 18, 2019
• Study Completion: October 19, 2019
• Last Updated: February 28, 2020

Record last verified: 2020-02

Data Sharing

• IPD Sharing: Will not share

Locations

CH (1)