Brief Summary

The investigators use paired associative stimulation (PAS) protocols to target cortico-cortical and cortico-subcortical networks to study cognitive deficits in methamphetamine addiction.

Trial Health

At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date

Enrollment

participants targeted

Target at P50-P75 for not_applicable

Timeline

Completed

Started May 2019

Typical duration for not_applicable

Geographic Reach

1 country

1 active site

Status

unknown

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

2.9 years study duration

First Submitted

Initial submission to the registry

April 5, 2019

Completed

5 days until next milestone

First Posted

Study publicly available on registry

April 10, 2019

Completed

21 days until next milestone

Study Start

First participant enrolled

May 1, 2019

Completed

1.9 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 31, 2021

Completed

1 year until next milestone

Study Completion

Last participant's last visit for all outcomes

March 31, 2022

Completed

Last Updated

September 14, 2021

Status Verified

September 1, 2021

Enrollment Period

1.9 years

First QC Date

April 5, 2019

Last Update Submit

September 13, 2021

Conditions

Methamphetamine-dependence

Keywords

Paired Associative StimulationFrontoparietal PathwayTranscranial Magnetic StimulationCognitive Function

Outcome Measures

Primary Outcomes (4)

Change of working memory
The N-Back is a working memory task where the subject is presented with a sequence of stimuli (letters). The task consists of indicating when the current stimulus matches the one from n steps earlier in the sequence.
30 minutes
Change of response inhibition
Response inhibition was assessed with the SST (Cambridge Cognition, Cambridge, UK). The subject responded to an arrow (go signal), pointing either right or left, by pressing one of two buttons with the right or left index finger. If an audio tone (stop signal) was present, the subject needed to withhold the response.
30 minutes
Change of attention bias
During the dot-probe task, participants are situated in front of a computer screen with their chin securely placed on a chin rest. Participants are asked to stare at a fixation cross on the center of the screen. Two stimuli, one of which is neutral and one of which is threatening, appear randomly on either side of the screen. The stimuli are presented for a predetermined length of time (most commonly 500ms), before a dot is presented in the location of one former stimulus. Participants are instructed to indicate the location of this dot as quickly as possible, either via keyboard or response box.
30 minutes
Change of risk decision
The Balloon Analogue Risk Task (BART) is a computerized measure of risk taking behavior. In the task, the participant is presented with a balloon and offered the chance to earn money by pumping the balloon up by clicking a button. Each click causes the balloon to incrementally inflate and money to be added to a counter up until some threshold, at which point the balloon is over inflated and explodes.
30 minutes

Secondary Outcomes (4)

Change of eeg oscillatory (Alpha, Beta, Theta and Delta)
30 minutes
Change of eeg functional connectivity (Alpha, Beta, Theta and Delta)
30 minutes
Change of motor evoked potential
30 minutes
Change of resting motor threshold
30 minutes

Study Arms (8)

DLPFC+10 IPL

EXPERIMENTAL

Stimulation of dorsolateral prefrontal cortex (DLPFC) 10 ms before inferior parietal lobule (IPL) presumes that the DLPFC to IPL input facilitates insula postsynaptic output activity, thereby improving cognition response via a long term potentiation-like effect.