The impact of cognitive training in substance use disorder: the effect of working memory training on impulse control in methamphetamine users.
OBJECTIVE
Impulsivity is a vulnerability trait for poor self-regulation in substance use disorder (SUD). Working memory (WM) training improves impulsivity and self-regulation in psychiatric disorders. Here we test WM training in methamphetamine use disorder (MUD).


METHODS
There are 15 MUD patients receiving inpatient treatment as usual (TAU) and 20 who additionally completed WM cognitive training (CT) and 25 healthy controls (HC). MANCOVA repeated measures analyses examined changes in impulsivity and self-regulation at baseline and after 4 weeks.


RESULTS
Post hoc t tests confirmed that at baseline, feelings of self-control were significantly lower in the MUD (t = 2.001, p = 0.05) and depression was higher (t = 4.980, p = 0.001), as was BIS total impulsivity (t = 5.370, p = 0.001) compared to the HC group. Total self-regulation score was higher in HC than MUD patients (t = 5.370, p = 0.001). CT had a 35% learning rate (R2= 0.3523, p < 0.05). Compared to follow-up TAU, follow-up CT group had higher self-reported mood scores (t = 2.784, p = 0.01) and higher compared to CT baseline (t = 2.386, p = 0.036). Feelings of self-control were higher in CT than TAU at follow-up (t = 2.736, p = 0.012) and also compared to CT baseline (t = 3.390, p = 0.006), lack of planning significantly improved in CT between baseline and follow-up (t = 2.219, p = 0.048), as did total impulsivity scores (t = 2.085, p = 0.048). Measures of self-regulation were improved in the CT group compared to TAU at follow-up, in total score (t = 2.442, p = 0.038), receiving score (t = 2.314, p = 0.029) and searching score (t = 2.362, p = 0.027). Implementing self-regulation was higher in the CT group compared to TAU (t = 2.373, p = 0.026).


CONCLUSIONS
WM training may improve control of impulsivity and self-regulation in people with MUD.
UCT Department of Psychiatry and Mental Health, Groote Schuur Hospital, Anzio Road, Observatory, Cape Town, South Africa. drsamanthabrooks@gmail.com.|Department of Neuroscience, Uppsala University, Uppsala, Sweden. drsamanthabrooks@gmail.com.
Samantha J
SJ
Brooks
Department of Neuroscience, Uppsala University, Uppsala, Sweden.
L
L
Wiemerslage
UCT Department of Psychiatry and Mental Health, Groote Schuur Hospital, Anzio Road, Observatory, Cape Town, South Africa.|Department of Neuroscience, University of Nottingham, Nottingham, UK.
K H
KH
Burch
UCT Department of Psychiatry and Mental Health, Groote Schuur Hospital, Anzio Road, Observatory, Cape Town, South Africa.|UCT Department of Psychology, Cape Town, South Africa.
S A
SA
Maiorana
UCT Department of Psychiatry and Mental Health, Groote Schuur Hospital, Anzio Road, Observatory, Cape Town, South Africa.
E
E
Cocolas
Department of Neuroscience, Uppsala University, Uppsala, Sweden.
H B
HB
Schiöth
Department of Psychology, University of the Western Cape, Cape Town, South Africa.
K
K
Kamaloodien
UCT Department of Psychiatry and Mental Health, Groote Schuur Hospital, Anzio Road, Observatory, Cape Town, South Africa.|MRC Unit on Anxiety and Stress Disorders, Cape Town, South Africa.
D J
DJ
Stein
D000328:Adult; D015928:Cognitive Behavioral Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D007175:Impulsive Behavior / Q000502:physiology*; D007858:Learning / Q000502:physiology; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects / Q000502:physiology*; D008694:Methamphetamine / Q000009:adverse effects*; D057566:Self Report; D016320:Substance Abuse Treatment Centers / Q000379:methods; D019966:Substance-Related Disorders / Q000523:psychology* / Q000628:therapy*; D055815:Young Adult
D008694:Methamphetamine
Impulsivity; Methamphetamine; Self-regulation; Working memory