Methamphetamine (MA) use disorder presents a substantial public health problem, in need of more effective treatments. This project focuses on attentional bias modification (ABM), using computer-based training as a therapeutic approach. Heightened attentional bias toward drug-related stimuli is a key feature of drug addiction and linked to craving and drug-seeking behavior. Bias toward MA-related stimuli has predicted retention in treatment and relapse, therefore, modification of attentional bias towards MA-related cues may be a useful therapeutic target in MA use disorder. The success of techniques used to reduce attentional bias toward cues related to alcohol, smoking, drugs and unhealthy food, as well as stimuli that induce anxiety holds promise for the application of ABM to MA use disorder. The ABM paradigm works by training attention away from salient cues towards neutral cues. Participants are presented with a neutral and MA-related image simultaneously and asked across multiple trials to identify a probe that replaces the images in one of two image locations. Faster response latencies to probes that replace drug versus neutral images is thought to indicate an attentional bias. ABM training involves increasing the proportion of probes appearing at the location of the neutral images. In the control condition, the probe follows MA-related and neutral images on an equal number of trials, providing no training of attentional bias. The project will test the effect of ABM training using two measures that are independent of the training protocol. These are (1) reaction time on the Visual Dot-Probe Task of Attentional Bias, which will use drug- related words and dots as stimuli and probes, respectively, instead of images and letters used during training, and (2) the time allocated to viewing drug-related images, measured using eye-tracking during the Simulated Drug-choice Task. Other variables assessed will be actual choice behavior, indicated by picture selection on the Simulated Drug-choice Task, and spontaneous MA craving. We will study MA users (both sexes, 18-50 years of age) attending an 8-week, residential behavioral treatment program and randomized to two groups - ABM and control. Both groups will undergo 3 sessions per week for 4 weeks.
The specific aims are to determine whether ABM reduces attentional bias, simulated drug choice, and spontaneous MA craving; and the extent to which reduced attentional bias toward MA-related stimuli may mediate reduced simulated drug choice and craving. We hypothesize that relative to the control group, the ABM group will exhibit reduced attentional bias to MA-related images, and that changes in attentional bias will statistically explain the reduction in selection of MA-related images during the Simulated Drug-Choice task and reduced craving for MA. Testing ABM as a way to modify attention away from drug-related cues in MA-dependent individuals is a novel approach and, because of its ease of administration, has potential to greatly expand available treatment options either as a primary intervention or adjunct to established therapeutic approaches for MA use disorder.
Methamphetamine use disorder is a problem with substantial, worldwide public health impact worldwide, which is highly resistant to available treatments. In order to evaluate a potential new treatment option, this project will test whether implementation of a computer-based training program can reduce attentional bias toward drug-related stimuli and associated drug craving in clients enrolled in a treatment program for methamphetamine addiction. Positive findings in this project can have substantial impact by identifying an inexpensive and readily implemented intervention, with downstream potential to greatly expand available treatment options.
