Investigating the Neural Correlates in Memory Retrieval After HD-tDCS

NCT ID: NCT03319134

Last Updated: 2020-08-26

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 45 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2017-09-18
• Study Completion Date: 2020-01-30

Brief Summary

The overall objective of this study is to investigate the neural correlate in retrieval memory task.

The aim of the study is to understand the undergoing changes in late positive ERP component during retrieval memory task when stimulating the posterior cingulate cortex (PCC) with High Definition Transcranial Direct Current Stimulation (HD-tDCS).

Detailed Description

Retrieval memory is supported by distinct retrieval process known as recollection and familiarity. These two process have been associated with distinct event related potentials (ERPs). At the time of retrieval, familiarity is associated with modulation of the FN400, an enhanced positivity for old items relative to new items observed from approximately 400-600ms post stimulus onset. The FN400 tends to have mid-frontal scalp distribution which can extend to left and right frontal areas and central midline regions. In contrast, recollection has been linked with modulation of positive going waveform that emerges approximately 600ms post stimulus and is typically maximal over parietal sites and referred to as late positive component (LPC). In addition, FN400 is found to increase gradually as a function of item retrieval confidence whereas LPC is limited to high confidence retrieval response.

High Definition transcranial Direct Current Stimulation (HD-tDCS ) is a non-invasive neuromodulation technique. Compared to the standard bipolar montage used by the conventional tDCS, it uses arrays of smaller, specially designed electrodes to deliver a constant and low current directly to the cortical brain areas to increase the spatial focality. Studies show that the cortical area undergoing stimulation with HD-tDCS is more restricted compared to the standard bipolar montage of conventional tDCS. Moreover, tDCS has been proposed as a therapeutic procedure in various diseases and tDCS in healthy adults have demonstrated to improve cognitive and memory performance, but information regarding the effects of HD-tDCS targeting the PCC and its impact on memory retrieval is scarce. By targeting the PCC area by HD-tDCS, we want to introduce a safer, easier-to-use and more accurate non-invasive neuromodulation procedure. The dysfunctions of posterior cingulate cortex hav been linked to a range of psychiatric and neurological condition such as Alzheimer's disease, schizophrenia, autism, depression and attention deficit hyperactivity disorder, as well as aging. It shows increased activity when subject retrieve autobiographical memories suggests its internal orientated function. PET and ERP combined studies have shown greater blood flow medial temporal lobe with a brief late positive ERP component in PCC. Therefore, in this study we aim to understand whether HD-tDCS targeting the PCC can modulate the late positive ERP component.

Conditions

Healthy Adults

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: DOUBLE

Study Groups

active anodal HD-tDCS

Active anodal HD-tDCS stimulation applied during memory task

Group Type: EXPERIMENTAL

active anodal HD-tDCS

Intervention Type: DEVICE

1\) active anodal HD-tDCS with memory task

sham HD-tDCS

Sham HD-tDCS stimulation during memory task for comparison

Group Type: SHAM_COMPARATOR

sham HD-tDCS

Intervention Type: DEVICE

2\) sham HD-tDCS with memory task

active cathodal HD-tDCS

Active cathodal HD-tDCS stimulation applied during memory task

Group Type: EXPERIMENTAL

active cathodal HD-tDCS

Intervention Type: DEVICE

3\) active cathodal HD-tDCS with memory task

Interventions

active anodal HD-tDCS

1\) active anodal HD-tDCS with memory task

Intervention Type: DEVICE

sham HD-tDCS

2\) sham HD-tDCS with memory task

Intervention Type: DEVICE

active cathodal HD-tDCS

3\) active cathodal HD-tDCS with memory task

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• Native English Speaker
• Currently not using any medication
• Capable of understanding and signing an informed consent

Exclusion Criteria

• Severe disease
• Mental illness
• Cardiac history
• History of severe head injuries
• History of epileptic seizures
• Any implanted devices such as pacemaker, neurostimulator
• Pregnancy

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 35 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

The University of Texas at Dallas

OTHER

Sponsor Role: lead

Responsible Party

Sven Vanneste

Associate professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Sven Vanneste

Role: PRINCIPAL_INVESTIGATOR

The University of Texas at Dallas

Locations

University of Texas at Dallas

Richardson, Texas, United States

Countries

United States

Provided Documents

Document Type: Study Protocol: Study Protocol

View Document

Other Identifiers

18-01

Identifier Type: -

Identifier Source: org_study_id