tDCS, Moral Decision-Making, fMRI

NCT ID: NCT04681391

Last Updated: 2020-12-23

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Total Enrollment

42 participants

Study Classification

OBSERVATIONAL

Study Start Date

2016-12-27

Study Completion Date

2020-12-10

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

Morality is the social rule about appropriateness of the behavior, containing concepts of justice, fairness, and rights. Previous studies suggested that the activation of right temporoparietal junction (rTPJ) should be involved in mental state reasoning in moral cognition. Implicit moral attitude, which reflects people's fundamental beliefs about right and wrong, could be assessed by implicit association test on moral scenarios (mIAT), as indicated by the D scores. According to our previous findings, we postulate that, during moral decision-making, the high D group would have less rTPJ involvement and the low D group would have more. Here we applied tDCS, a non-invasive neuromodulation technique, to modulate cortical excitability in rTPJ.

Based on our postulation, we divided participants into high D and low D group and hypothesized that tDCS over rTPJ would modulate the behavior depending on the group. The results revealed that, in aspect of mIAT, implicit moral attitude could be modulated differently depending on the group via tDCS over rTPJ. In addition, hemodynamic response within rTPJ showed a main effect of tDCS while carrying out the helping behavior. In conclusion, these findings indicated that tDCS over rTPJ could modulate the implicit moral attitude as well as the rTPJ activity during moral action.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Morality

Keywords

Explore important study keywords that can help with search, categorization, and topic discovery.

tDCS, Moral Decision-Making, Implicit Attitude, fMRI

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Observational Model Type

OTHER

Study Time Perspective

OTHER

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

anodal

For the active stimulation, which are anodal and cathodal tDCS, a constant current of 1 mA was delivered through 35 cm2 electrode for 20 minutes with fade-in and fade-out of 10 seconds, producing a current density of 0.029 mA/cm2. During anodal tDCS, the anode was placed over right temporoparietal junction, and the cathode was placed over left supraorbital area.

transCranial direct current stimulation

Intervention Type DEVICE

In the present study, we applied DC Brain Stimulator Plus to stimulate right temporoparietal junction (rTPJ). The target electrode was placed over the location of rTPJ; on the other hand, the return electrode was placed over the left supraorbital area. That is, during anodal tDCS, the anode was placed over CP6, and the cathode was placed over left supraorbital area; conversely, during cathodal tDCS, the cathode was placed over CP6, and the anode was placed over left supraorbital area. For the active stimulation, which are anodal and cathodal tDCS, a constant current of 1 mA was delivered through 35 cm2 electrode for 20 minutes with fade-in and fade-out of 10 seconds, producing a current density of 0.029 mA/cm2. On the other hand, same fade-in, fade-out, and current density were applied for the sham stimulation, but the duration of current-delivering only last 35 seconds. Therefore, participants could feel the skin sensation but did not have the after-effects of tDCS.

cathodal

For the active stimulation, which are anodal and cathodal tDCS, a constant current of 1 mA was delivered through 35 cm2 electrode for 20 minutes with fade-in and fade-out of 10 seconds, producing a current density of 0.029 mA/cm2. During cathodal tDCS, the cathode was placed over right temporoparietal junction, and the anode was placed over left supraorbital area.

transCranial direct current stimulation

Intervention Type DEVICE

In the present study, we applied DC Brain Stimulator Plus to stimulate right temporoparietal junction (rTPJ). The target electrode was placed over the location of rTPJ; on the other hand, the return electrode was placed over the left supraorbital area. That is, during anodal tDCS, the anode was placed over CP6, and the cathode was placed over left supraorbital area; conversely, during cathodal tDCS, the cathode was placed over CP6, and the anode was placed over left supraorbital area. For the active stimulation, which are anodal and cathodal tDCS, a constant current of 1 mA was delivered through 35 cm2 electrode for 20 minutes with fade-in and fade-out of 10 seconds, producing a current density of 0.029 mA/cm2. On the other hand, same fade-in, fade-out, and current density were applied for the sham stimulation, but the duration of current-delivering only last 35 seconds. Therefore, participants could feel the skin sensation but did not have the after-effects of tDCS.

sham (as a control condition)

same fade-in, fade-out, and current density were applied for the sham stimulation, but the duration of current-delivering only last 35 seconds.

transCranial direct current stimulation

Intervention Type DEVICE

In the present study, we applied DC Brain Stimulator Plus to stimulate right temporoparietal junction (rTPJ). The target electrode was placed over the location of rTPJ; on the other hand, the return electrode was placed over the left supraorbital area. That is, during anodal tDCS, the anode was placed over CP6, and the cathode was placed over left supraorbital area; conversely, during cathodal tDCS, the cathode was placed over CP6, and the anode was placed over left supraorbital area. For the active stimulation, which are anodal and cathodal tDCS, a constant current of 1 mA was delivered through 35 cm2 electrode for 20 minutes with fade-in and fade-out of 10 seconds, producing a current density of 0.029 mA/cm2. On the other hand, same fade-in, fade-out, and current density were applied for the sham stimulation, but the duration of current-delivering only last 35 seconds. Therefore, participants could feel the skin sensation but did not have the after-effects of tDCS.

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

transCranial direct current stimulation

In the present study, we applied DC Brain Stimulator Plus to stimulate right temporoparietal junction (rTPJ). The target electrode was placed over the location of rTPJ; on the other hand, the return electrode was placed over the left supraorbital area. That is, during anodal tDCS, the anode was placed over CP6, and the cathode was placed over left supraorbital area; conversely, during cathodal tDCS, the cathode was placed over CP6, and the anode was placed over left supraorbital area. For the active stimulation, which are anodal and cathodal tDCS, a constant current of 1 mA was delivered through 35 cm2 electrode for 20 minutes with fade-in and fade-out of 10 seconds, producing a current density of 0.029 mA/cm2. On the other hand, same fade-in, fade-out, and current density were applied for the sham stimulation, but the duration of current-delivering only last 35 seconds. Therefore, participants could feel the skin sensation but did not have the after-effects of tDCS.

Intervention Type DEVICE

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* healthy volunteers, are all ethnic Chinese, right-handed, and aged between 20 to 30 years old

Exclusion Criteria

* any history of psychiatry or neurological disorders (e.g., dementia, seizures), head injury, and alcohol or substance abuse
Minimum Eligible Age

20 Years

Maximum Eligible Age

30 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

National Yang Ming Chiao Tung University Hospital

OTHER

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Responsibility Role SPONSOR

References

Explore related publications, articles, or registry entries linked to this study.

Ciaramelli E, Muccioli M, Ladavas E, di Pellegrino G. Selective deficit in personal moral judgment following damage to ventromedial prefrontal cortex. Soc Cogn Affect Neurosci. 2007 Jun;2(2):84-92. doi: 10.1093/scan/nsm001.

Reference Type BACKGROUND
PMID: 18985127 (View on PubMed)

FeldmanHall O, Mobbs D, Evans D, Hiscox L, Navrady L, Dalgleish T. What we say and what we do: the relationship between real and hypothetical moral choices. Cognition. 2012 Jun;123(3):434-41. doi: 10.1016/j.cognition.2012.02.001. Epub 2012 Mar 9.

Reference Type BACKGROUND
PMID: 22405924 (View on PubMed)

Fumagalli M, Priori A. Functional and clinical neuroanatomy of morality. Brain. 2012 Jul;135(Pt 7):2006-21. doi: 10.1093/brain/awr334. Epub 2012 Feb 13.

Reference Type BACKGROUND
PMID: 22334584 (View on PubMed)

Nitsche MA, Paulus W. Excitability changes induced in the human motor cortex by weak transcranial direct current stimulation. J Physiol. 2000 Sep 15;527 Pt 3(Pt 3):633-9. doi: 10.1111/j.1469-7793.2000.t01-1-00633.x.

Reference Type BACKGROUND
PMID: 10990547 (View on PubMed)

Gaesser B, Hirschfeld-Kroen J, Wasserman EA, Horn M, Young L. A role for the medial temporal lobe subsystem in guiding prosociality: the effect of episodic processes on willingness to help others. Soc Cogn Affect Neurosci. 2019 May 17;14(4):397-410. doi: 10.1093/scan/nsz014.

Reference Type RESULT
PMID: 30809675 (View on PubMed)

Santiesteban I, Banissy MJ, Catmur C, Bird G. Enhancing social ability by stimulating right temporoparietal junction. Curr Biol. 2012 Dec 4;22(23):2274-7. doi: 10.1016/j.cub.2012.10.018. Epub 2012 Nov 1.

Reference Type RESULT
PMID: 23122848 (View on PubMed)

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

2016B008

Identifier Type: -

Identifier Source: org_study_id