Skip to main content
OpenTrials
Completed

NCT Number: NCT02119949

Working Memory Training for Substance Dependent Individuals

Background: Substance abusers show impaired working memory (WM) functioning. Promising findings show training WM results in an improved working memory capacity (WMC) and a decrease of clinical symptoms in a range of disorders, including alcohol addiction.

Aim: To test the effect of a WM training in addition to treatment as usual (TAU) on substance use, craving, WMC, impulsivity, attention bias and psychopathology.

Design: A randomized double-blind placebo-controlled trial with a parallel group design. The WM training adapted to participants' WMC whereas the placebo training consisted of non-adaptive easy versions of these tasks.

Setting: Two departments of an addiction treatment clinic in Rotterdam, the Netherlands.

Participants: 120 inpatients diagnosed with an alcohol, cannabis or cocaine dependency who were in treatment as usual .

Measurements: Primary outcome measures: Substance use and craving. Secondary outcome measures: WMC, impulsivity, attention bias and psychopathology. Participants were assessed before and after 24 sessions of WM training as well as two months after the training.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Substance Dependency Addiction Anxiety Anxiety Disorders Behavior Behavior, Addictive Behavioral Symptoms Chemically-Induced Disorders Compulsive Behavior Depression Impulsive Behavior Mental Disorders Substance-Related Disorders

Age range

16 year–67 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Bouman Clinic

Rotterdam, South Holland, 3084 LD, Netherlands

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Substance dependency: cocaine, cannabis or alcohol

Exclusion criteria

  • Age below 16 or above 67
  • Current psychosis
  • Neurological complaints

Treatment and study plan

Working memory training

Behavioral

The working memory training started the day after the pre-test and included 24 sessions of 25 minutes each. Participants trained, under supervision of an experimenter, on weekdays in the clinic. The training consisted of two tasks: the Symmetry Span and the N-back Task. Participants in the experimental group executed versions of these task that adapt to their working memory capacity, to train their working memory optimally.

Placebo training

Behavioral

The working memory training started the day after the pre-test and included 24 sessions of 25 minutes each. Participants trained, under supervision of an experimenter, on weekdays in the clinic. The training consisted of two tasks: the Symmetry Span and the N-back Task. Participants in the placebo group executed easy versions of these task that did not adapt to their level, to prevent training.

Primary outcomes

  1. Craving: Desires for Alcohol Questionnaire and Desires for Drug Questionnaire score change and Obsessive Compulsive Drug Use Scale and Obsessive Compulsive Drinking Scale score change between pre and post training and follow up (two months after post)

    Time frame: Pre (baseline), post (after 4 weeks of training-starting 1 day after pre-test) and follow-up (2 months after post-test)

    The 14-item Desires for Drug Questionnaire (DDQ) and the 13-item Desires for Alcohol Questionnaire (DAQ) measure instant craving to respectively drug and alcohol. The DDQ is based on the DAQ.

    The Obsessive Compulsive Drug Use Scale (OCDUS) and Obsessive Compulsive Drinking Scale (OCDS) measure the subjective interference and distress caused by respectively drug and alcohol related thoughts and compulsive-behavior patterns.

Secondary outcomes

  1. Change in Digit Span score on pre and post training and follow up after two months

    Time frame: Pre (baseline), post (after 4 weeks of training-starting 1 day after pre-test) and follow-up (2 months after post-test)

    The Digit Span task consists of two parts: the forward Digit Span is a frequently used measure for short term memory, an important subcomponent of the memory system (Shipstead, Redick, & Engle, 2012) and the backward version measures WM.

  2. Change in Reading Span partial-scredit uni score on pre and post training and follow up after two months

    Time frame: Pre (baseline), post (after 4 weeks of training-starting 1 day after pre-test) and follow-up (2 months after post-test)

    The Reading Span measures the processing and storage functions of WM (Shipstead et al., 2012), specifically participants' ability to shift between two tasks and to cope with proactive interference.

Other outcomes

  1. Change in Barratt Impulsivity Scale-11 score on pre and post training and follow up after two months

    Time frame: Pre (baseline), post (after 4 weeks of training-starting 1 day after pre-test) and follow-up (2 months after post-test)

    The 30-item Barratt Impulsivity Scale-11 (BIS-11) measures impulsivity.

  2. Change in Stroop score on pre and post training and follow up after two months

    Time frame: Pre (baseline), post (after 4 weeks of training-starting 1 day after pre-test) and follow-up (2 months after post-test)

    The Stroop measures participants' attention bias for addiction related stimuli.

  3. Change in Beck Depression Inventory - Second Edition (BDI-II) score on pre and post training and follow up after two months

    Time frame: Pre (baseline), post (after 4 weeks of training-starting 1 day after pre-test) and follow-up (2 months after post-test)

    The Beck Depression Inventory - Second Edition (BDI-II) measures the severity of depression in 21 statements, with four levels of increasing severity each.

  4. Change in State-Trait Anxiety Inventory (STAI) score on pre and post training and follow up after two months

    Time frame: Pre (baseline), post (after 4 weeks of training-starting 1 day after pre-test) and follow-up (2 months after post-test)

    The State-Trait Anxiety Inventory (STAI) measures self-reported anxiety in 40 questions on a 4-point scale. The questionnaire consists of two parts; state and trait anxiety, respectively transient and dispositional anxiety.

  5. Change in substance use, measured with the Addiction Severity Index over pre-, post (1 day after training) and follow-up (2 months after post-test) measurements.

    Time frame: Pre (baseline), post (after 4 weeks of training-starting 1 day after pre-test) and follow-up (2 months after post-test)

    The Addiction Severity Index (ASI) is a semi-structured interview that measures the severity of addiction in 25 questions concerning seven problem areas: medical problems, employment problems, drug use, alcohol use, family and social problems, criminality, and psychiatric problems. We used three of these questions to assess the severity of participants' abuse problems.

Sponsors and collaborators

Lead sponsor

Erasmus Medical Center

Other

Registry information

Official study title

A Randomized Double-blind Placebo-controlled Trial to Working Memory Training in Substance Abusers

Important dates

Study start
2012
Primary completion
2014
Study completion
2014
First posted
Apr 22, 2014
Registry last updated
Aug 21, 2014

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.