Training and transfer effects of working memory updating training in male abstinent long-term methamphetamine users

Xin Zhao,Lei Wang,Joseph H.R Maes

doi:10.1016/j.abrep.2021.100385

Abstract

Methamphetamine use is associated with cognitive impairments, including executive functioning. These impairments might be cause and/or effect of the drug (re-)use and have, therefore, motivated interventions to improve cognitive functioning. Until now, only very few studies have examined the effect of training working memory updating (WMU), one of the core executive functions, in this population. In the present study, 32 long-term male abstinent methamphetamine inpatients received either a multiple-session WMU training or an active control treatment. All participants performed a number of tasks assessing WMU, inhibition, and task-switching ability- before and after treatment. The WMU-trained patients improved their performance on the trained task and on a non-trained WMU task, reflecting near transfer. However, there was no beneficial training-induced effect for the other tasks, indicating the absence of far transfer. Possible treatment implications of these findings were discussed.

Highlights

Methamphetamine is a synthetic psychostimulant drug that is widely abused in both western and eastern countries (e.g., National Institute on Drug Abuse, 2021; United Nations Office on Drugs and Crime, 2020)
We examined whether individual differences in training progress were significantly correlated with individual differences in the transfer benefit that we observed for the RMT
This study assessed the effects of a multiple-day, adaptive working memory updating (WMU) training program on the executive functioning of long-term, abstinent inpatient methamphetamine users

Summary

Introduction

At least some of the latter two types of effect are mediated by the adverse impact that methamphet amine abuse has on cognitive functioning, including processing speed, language, learning, memory, decision-making, and executive func tioning, and underlying brain structures (e.g., Dean, Groman, Morales, & London, 2013; Ellis et al, 2016; Fitzpatrick, Rubenis, Lubman, & Verdejo-Garcia, 2020; Nestor, Ghahremani, Monterosso, & London, 2011; Potvin et al, 2018; Scott et al, 2007; Weber et al, 2012) These neurocognitive deficits can either be a result of the (ab)use, a predis posing factor for the initial (ab)use or relapse after abstinence, or both (e.g., Basterfield, Hester, & Bowden, 2019; Lyoo et al, 2015; see Mizoguchi & Yamada, 2019, for research with rodents). Studies providing evidence for a positive correlation between drug use duration and cognitive deficits and/or for prolonged deficits even after protracted abstinence (e.g., Farhadian, Akbarfahimi, Hassaniabharian, Hosseini, & Shokri, 2017; Proebstl et al, 2019) motivate the development of interventions to relieve methamphetamine-induced cognitive deficits

Methods

Results

Discussion

Conclusion