The Effect of Transcranial Direct Current Stimulation of the Prefrontal Cortex on Antisocial Behavior
Overview
- Phase
- N/A
- Intervention
- Not specified
- Conditions
- Aggression
- Sponsor
- Nanyang Technological University
- Enrollment
- 101
- Locations
- 1
- Primary Endpoint
- Delay discounting rates after stimulation
- Status
- Active, Not Recruiting
- Last Updated
- 3 years ago
Overview
Brief Summary
The main objective of this study is to investigate the causal relationship between prefrontal cortex activity and antisocial behavior, as well as risk factors for antisocial behavior. Specifically, this study tests the hypothesis that upregulating activity in the prefrontal cortex through a non-invasive form of brain stimulation, transcranial direct current stimulation (tDCS) will reduce antisocial and aggressive behavior. The effects of 3 days of anodal stimulation over the prefrontal cortex are assessed.
Investigators
Olivia Choy
Assistant Professor
Nanyang Technological University
Eligibility Criteria
Inclusion Criteria
- •Above 18 (with parental consent) or above 21 (without parental consent)
- •Able to understand the nature of the study and give informed consent
Exclusion Criteria
- •History of or active neurologic, cardiovascular, or psychiatric disease including anxiety disorders (e.g., PTSD, panic attacks, obsessive-compulsive disorder) and mood disorders (e.g., depression)
- •Currently consuming anti-convulsant, anti-psychotic, or sedative/hypnotic medications
- •Currently consuming anti-depressants
- •History of seizures
- •Metallic implants on scalp
- •Participated in any other non-invasive brain stimulation study in the same day
- •Ever had an adverse reaction to tDCS
Outcomes
Primary Outcomes
Delay discounting rates after stimulation
Time Frame: Within 1 hour after the third consecutive active tDCS or sham session
Participants' responses to 5 questions indicating if they would prefer a smaller reward today or a larger reward in the specified number of days will be assessed. The delay discount rates (k) of monetary rewards will be calculated based on the responses to the 5 trials.
Points in the Point Subtraction Aggression Paradigm after stimulation
Time Frame: Within 1 hour after the third consecutive active tDCS or sham session
The number of points earned on the lab task will be assessed.
Helping behavior after stimulation
Time Frame: Within 1 hour after the third consecutive active tDCS or sham session
This will be assessed based on the number of easy and hard puzzles participants choose to assign to another participant in the study.
Antisocial behavior after stimulation
Time Frame: Within 1 hour after the third consecutive active tDCS or sham session
This will be assessed based on the participants' accurate reporting of the number of problems correctly solved in a task.
Moral judgment ratings after stimulation
Time Frame: Within 1 hour after the third consecutive active tDCS or sham session
This will be assessed using 5 hypothetical scenarios in which someone commits a criminal or antisocial act. Participants will rate the moral wrongfulness of the act in the scenario on a scale from 0 (not at all) to 10 (very). A higher score reflects a greater perception of moral wrongfulness regarding the antisocial act.
Antisocial behavior inclinations after stimulation
Time Frame: Within 1 hour after the third consecutive active tDCS or sham session
This will be assessed using 5 hypothetical scenarios in which someone commits a criminal or antisocial act. Participants will respond to the likelihood that they would commit the act in the scenario according to a 10-point Likert scale. Responses are measured on a scale ranging from zero (no chance at all) to 10 (100% chance). A higher value reflects a greater intention to engage in the antisocial act.
Secondary Outcomes
- Number of participants with adverse events(Within 1 hour after each of the 20-minute active tDCS or sham sessions)