AUTHOR=Liu Weijun , Tian Yu , Yan Xinyu , Yang Jiemin TITLE=Impulse Inhibition Ability With Methamphetamine Dependents Varies at Different Abstinence Stages JOURNAL=Frontiers in Psychiatry VOLUME=12 YEAR=2021 URL=https://www.frontiersin.org/journals/psychiatry/articles/10.3389/fpsyt.2021.626535 DOI=10.3389/fpsyt.2021.626535 ISSN=1664-0640 ABSTRACT=

Objective: The purpose of this study is to evaluate whether the impulse inhibition ability with methamphetamine dependents would vary at different abstinence stages.

Methods: Sixty-three methamphetamine dependents, including 31 short-term (< 10 months) and 32 long-term (≥ 10 months) abstinence participants, were recruited for this study. In addition, 33 men were recruited as the healthy control (HC) group. All participants performed a two-choice oddball task, which is well-established to assess impulse inhibition. Accuracy for deviant trials and deviant–standard reaction time (RT) delay were computed as indexes of impulse inhibition.

Results: The accuracy for deviant trials was significantly decreased in short-term abstinence subjects (90.61%) compared to HC subjects (95.42%, p < 0.01), which was coupled with a shorter RT delay reflecting greater impulsivity in the short-term group vs. the HC group (47 vs. 73 ms, p < 0.01). However, impulse inhibition was improved in the long-term group, shown by the increased accuracy for deviant trials in the long-term group compared to the short-term group (94.28 vs. 90.61%, p < 0.05) and the similar accuracy for the long-term and HC groups (p > 0.05). Further regression analyses confirmed that the abstinence duration positively predicted impulse inhibition of methamphetamine dependents, both in accuracy and RT for deviant stimulus (β = 0.294, p = 0.019; β = 0.337, p = 0.007).

Conclusion: These results suggest that long-term abstinence is more effective in improving impulse inhibition with methamphetamine dependents.