Trial Outcomes & Findings for The Effect of Prefrontal Cortex Stimulation on Antisocial and Aggressive Behavior (NCT NCT02427672)

Last Updated: 2019-08-28

Results Overview

This will be assessed using hypothetical scenarios in which someone commits a criminal or antisocial act. The two brief scenarios describe a physical assault and a sexual assault. Participants will respond to the likelihood that they would commit the act in the scenario according to a 10-point Likert scale. Responses were measured on a scale ranging from zero (no chance at all) to ten (100 percent chance). Scores for both scenarios were summed to obtain an overall measure of intentions to commit aggression. Possible scores range from 0 to 20. A higher value indicates a greater inclination to engage in the antisocial act.

Recruitment status

COMPLETED

Study phase

Target enrollment

84 participants

Primary outcome timeframe

Baseline (an average of 15 minutes before receiving tDCS or sham) and on average, 24 hours following stimulation or sham

Results posted on

2019-08-28

Participant Flow

Participant milestones

Participant milestones
Measure	Anodal Stimulation Participants in the active stimulation group will undergo anodal bilateral transcranial direct current stimulation (tDCS) of the dorsolateral prefrontal cortex. tDCS will be delivered by a battery-driven, constant-current stimulator connected to three saline-soaked surface sponge electrodes. Two anodal electrodes (25cm2) will be placed over the dorsolateral prefrontal cortex bilaterally and one cathodal electrode (35cm2) will be placed at the back of the neck. Scalp electrodes will be positioned over the F3 and F4 according to the 10-20 EEG international system. A current of 1mA will be applied for 20 minutes and the current will be ramped up and down at the beginning and end of the stimulation period. Transcranial direct current stimulation	Sham Stimulation The sham transcranial direct current stimulation condition will involve the same placement of the electrodes, current intensity, and ramp time as the real tDCS condition, but stimulation will only last for 30 seconds. Sham transcranial direct current stimulation
Overall Study STARTED	40	44
Overall Study COMPLETED	39	42
Overall Study NOT COMPLETED	1	2

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

The Effect of Prefrontal Cortex Stimulation on Antisocial and Aggressive Behavior

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Anodal Stimulation n=39 Participants Participants in the active stimulation group will undergo anodal bilateral transcranial direct current stimulation (tDCS) of the dorsolateral prefrontal cortex. tDCS will be delivered by a battery-driven, constant-current stimulator connected to three saline-soaked surface sponge electrodes. Two anodal electrodes (25cm2) will be placed over the dorsolateral prefrontal cortex bilaterally and one cathodal electrode (35cm2) will be placed at the back of the neck. Scalp electrodes will be positioned over the F3 and F4 according to the 10-20 EEG international system. A current of 1mA will be applied for 20 minutes and the current will be ramped up and down at the beginning and end of the stimulation period. Transcranial direct current stimulation	Sham Stimulation n=42 Participants The sham transcranial direct current stimulation condition will involve the same placement of the electrodes, current intensity, and ramp time as the real tDCS condition, but stimulation will only last for 30 seconds. Sham transcranial direct current stimulation	Total n=81 Participants Total of all reporting groups
Age, Continuous	20.26 years STANDARD_DEVIATION 4.13 • n=5 Participants	20.17 years STANDARD_DEVIATION 2.36 • n=7 Participants	20.21 years STANDARD_DEVIATION 3.31 • n=5 Participants
Sex: Female, Male Female	24 Participants n=5 Participants	21 Participants n=7 Participants	45 Participants n=5 Participants
Sex: Female, Male Male	15 Participants n=5 Participants	21 Participants n=7 Participants	36 Participants n=5 Participants
Race/Ethnicity, Customized Caucasian	17 Participants n=5 Participants	19 Participants n=7 Participants	36 Participants n=5 Participants
Race/Ethnicity, Customized Non-Caucasian	22 Participants n=5 Participants	23 Participants n=7 Participants	45 Participants n=5 Participants
Region of Enrollment United States	39 Participants n=5 Participants	42 Participants n=7 Participants	81 Participants n=5 Participants

PRIMARY outcome

Timeframe: Baseline (an average of 15 minutes before receiving tDCS or sham) and on average, 24 hours following stimulation or sham

Outcome measures

Outcome measures
Measure	Anodal Stimulation n=39 Participants Participants in the active stimulation group will undergo anodal bilateral transcranial direct current stimulation (tDCS) of the dorsolateral prefrontal cortex. tDCS will be delivered by a battery-driven, constant-current stimulator connected to three saline-soaked surface sponge electrodes. Two anodal electrodes (25cm2) will be placed over the dorsolateral prefrontal cortex bilaterally and one cathodal electrode (35cm2) will be placed at the back of the neck. Scalp electrodes will be positioned over the F3 and F4 according to the 10-20 EEG international system. A current of 1mA will be applied for 20 minutes and the current will be ramped up and down at the beginning and end of the stimulation period. Transcranial direct current stimulation	Sham Stimulation n=42 Participants The sham transcranial direct current stimulation condition will involve the same placement of the electrodes, current intensity, and ramp time as the real tDCS condition, but stimulation will only last for 30 seconds. Sham transcranial direct current stimulation
Change in Antisocial Behavior Inclinations at 24 Hours	1.41 score on a scale Standard Error .33	3.05 score on a scale Standard Error .68

PRIMARY outcome

Timeframe: On average, 24 hours after the tDCS or sham session

The number of pins (between 0 and 51) that participants decide to insert into a picture of a voodoo doll on a computer that represents either a romantic partner or close friend will be recorded on average 24 hours after receiving tDCS or sham stimulation.

Outcome measures

Outcome measures
Measure	Anodal Stimulation n=39 Participants Participants in the active stimulation group will undergo anodal bilateral transcranial direct current stimulation (tDCS) of the dorsolateral prefrontal cortex. tDCS will be delivered by a battery-driven, constant-current stimulator connected to three saline-soaked surface sponge electrodes. Two anodal electrodes (25cm2) will be placed over the dorsolateral prefrontal cortex bilaterally and one cathodal electrode (35cm2) will be placed at the back of the neck. Scalp electrodes will be positioned over the F3 and F4 according to the 10-20 EEG international system. A current of 1mA will be applied for 20 minutes and the current will be ramped up and down at the beginning and end of the stimulation period. Transcranial direct current stimulation	Sham Stimulation n=42 Participants The sham transcranial direct current stimulation condition will involve the same placement of the electrodes, current intensity, and ramp time as the real tDCS condition, but stimulation will only last for 30 seconds. Sham transcranial direct current stimulation
Number of Pins Inserted Into a Virtual Voodoo Doll at 24 Hours	5.31 pins Standard Error 1.90	2.62 pins Standard Error 1.32

Adverse Events

Anodal Stimulation

Serious events: 0 serious events

Other events: 39 other events

Deaths: 0 deaths

Sham Stimulation

Serious events: 0 serious events

Other events: 39 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	Anodal Stimulation n=39 participants at risk Participants in the active stimulation group will undergo anodal bilateral transcranial direct current stimulation (tDCS) of the dorsolateral prefrontal cortex. tDCS will be delivered by a battery-driven, constant-current stimulator connected to three saline-soaked surface sponge electrodes. Two anodal electrodes (25cm2) will be placed over the dorsolateral prefrontal cortex bilaterally and one cathodal electrode (35cm2) will be placed at the back of the neck. Scalp electrodes will be positioned over the F3 and F4 according to the 10-20 EEG international system. A current of 1mA will be applied for 20 minutes and the current will be ramped up and down at the beginning and end of the stimulation period. Transcranial direct current stimulation	Sham Stimulation n=42 participants at risk The sham transcranial direct current stimulation condition will involve the same placement of the electrodes, current intensity, and ramp time as the real tDCS condition, but stimulation will only last for 30 seconds. Sham transcranial direct current stimulation
Skin and subcutaneous tissue disorders Itchiness	92.3% 36/39 • Number of events 36 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.	78.6% 33/42 • Number of events 33 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.
General disorders Lightheadedness	48.7% 19/39 • Number of events 19 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.	33.3% 14/42 • Number of events 14 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.
General disorders Pain	51.3% 20/39 • Number of events 20 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.	42.9% 18/42 • Number of events 18 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.
Skin and subcutaneous tissue disorders Burning	59.0% 23/39 • Number of events 23 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.	40.5% 17/42 • Number of events 17 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.
Skin and subcutaneous tissue disorders Warmth	56.4% 22/39 • Number of events 22 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.	45.2% 19/42 • Number of events 19 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.
Skin and subcutaneous tissue disorders Pinching	46.2% 18/39 • Number of events 18 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.	45.2% 19/42 • Number of events 19 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.
General disorders Iron taste	10.3% 4/39 • Number of events 4 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.	4.8% 2/42 • Number of events 2 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.
General disorders Fatigue	38.5% 15/39 • Number of events 15 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.	33.3% 14/42 • Number of events 14 • The presence of an adverse event was assessed during the course of one experimental session, from the 20-minute stimulation or sham period to the time that participants completed all study tasks, up to 1 hour. Subjects responded to a questionnaire regarding 8 possible sensations that may have resulted from tDCS.

Additional Information

Dr. Olivia Choy

Nanyang Technological University

Phone: (65)65921522

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place