fMRI Analysis of Aging and Awareness in Conditioning

NCT03655769 | Active Not Recruiting

• 2 other identifiers: NA_00045404R01AG021501
• Study Type: interventional
• Target: 16
• Locations: 0 countries
• Sites: N/A

Brief Summary

Cathodal Transcranial direct current stimulation (tDCS) was administered to the right parietal region in order to determine if this stimulation could disrupt awareness of the conditioned stimulus (CS) - unconditioned stimulus (US) relationship in a classical conditioning experiment.

Conditions

Transcranial Direct Current Stimulation

Outcome Measures

Primary Outcomes (1)

• CS-US Awareness

  To assess CS-US awareness, we used a questionnaire The questionnaire consists of 7 true/false questions about the sequence and co-occurrence of the conditioned stimulus (CS, a 1000 Hz tone) and unconditioned stimulus (US, a 100 ms puff of air to the eye). The score can thus range from 0 to 7. Higher score values indicate better awareness of the sequence and co-occurrence of the CS and US

  recorded immediately after the 20 minutes of tDCS stimulation

Secondary Outcomes (2)

• Line bisection test of left-hemifield neglect

  recorded immediately after primary awareness questionnaire

• Eyeblink conditioned responding

  recorded during the tDCS administration

Study Arms (2)

sham tDCS

SHAM COMPARATOR

tDCS delivered for only 30 sec to replicate tingling sensation and blind subject

Device: sham transcranial direct current stimulation

cathodal tDCS

EXPERIMENTAL

cathodal tDCS, 2 milliamps (mA), delivered to right parietal region

Device: transcranial direct current stimulation

Interventions

transcranial direct current stimulation DEVICE

transcranial direct current stimulation applied at 2 mA over the right parietal region for 20 min

cathodal tDCS

sham transcranial direct current stimulation DEVICE

transcranial direct current stimulation applied at 2 mA over the right parietal region for 30 sec

sham tDCS

Eligibility Criteria

• Age: 20 Years - 30 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Educational attainment of at least eight years and English as the native language
• Mini-Mental State Examination (MMSE) score of 26
• Normal episodic memory (i.e., CERAD word List Recall \> 5)
• Informed consent; 5) age of 20-30

You may not qualify if:

• Disturbed consciousness
• Other neurological or systemic disorder which can cause dementia or cognitive dysfunction
• Prior history of a major psychiatric disorder
• History of definite stroke
• Focal lesion on MRI exam
• Use of anxiolytic, antidepressant, neuroleptic, or sedative medication
• Predominately left-handed
• Has MRI contraindication such as pacemaker, implanted pumps, shrapnel, etc. (full MRI screening form will be filled out).

Sponsors & Collaborators

• Johns Hopkins University: lead
• National Institute on Aging (NIA): collaborator

MeSH Terms

Interventions

Transcranial Direct Current Stimulation

Intervention Hierarchy (Ancestors)

Electric Stimulation Therapy; Therapeutics; Convulsive Therapy; Psychiatric Somatic Therapies; Behavioral Disciplines and Activities; Electroshock; Psychological Techniques

Study Officials

• John Desmond

  Johns Hopkins University

  PRINCIPAL INVESTIGATOR

Study Design

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

Study Record Dates

• First Submitted: August 30, 2018
• First Posted: August 31, 2018
• Study Start: November 9, 2010
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2026
• Last Updated: December 11, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share