Gamified Adaptive Approach Bias Modification on Individuals With Methamphetamine Use History

A randomized controlled trial will be conducted to investigate whether a proposed algorithm that adjusts the congruency ratio based on the user's performance and difficulty can enhance the effectiveness of approach bias modification. Methamphetamine users will be recruited and randomized into an algorithm group, a standard group, and a control group.

To assess the efficacy of an adaptive approach bias modification (A-ApBM) paradigm with gamified designs and dynamic difficulty adjustments in reducing cue-induced craving in individuals with methamphetamine use history. DESIGN: Randomized controlled trial with three study groups: Adaptive ApBM (A-ApBM), Static ApBM (S-ApBM), and control. A-ApBM and S-ApBM groups engaged in ApBM training using a smartphone application for four weeks. A-ApBM used an adaptive algorithm to dynamically adjust the difficulty level based on individual performance, while S-ApBM had a static difficulty level. Cue-induced craving scores were assessed using a visual analog scale at baseline, post-intervention, and at week-16 follow-up.

In the static approach bias modification, users were instructed to swipe upward when they see portrait format images and swipe downward when they see landscape format images. A shrinking animation comes after swiping upward to simulate the visual effect of moving away (approach), and a growing animation comes after swiping downward to simulate the visual effect of moving towards (avoidance). Two types of images, namely drug-related and non-drug-related, were used in the training. The drug-related images were related to methamphetamine (methamphetamine crystals, powders, and paraphernalia), and the non-drug-related images were related to healthy lifestyles (wealth, sports, gourmet, family activities, etc).

In the adaptive approach bias modification, users were instructed to swipe upward when they see portrait format images and swipe downward when they see landscape format images. A shrinking animation comes after swiping upward to simulate the visual effect of moving away (approach), and a growing animation comes after swiping downward to simulate the visual effect of moving towards (avoidance). Two types of images, namely drug-related and non-drug-related, were used in the training. The drug-related images were related to methamphetamine (methamphetamine crystals, powders, and paraphernalia), and the non-drug-related images were related to healthy lifestyles (wealth, sports, gourmet, family activities, etc). An algorithm continuously monitors the performance of the user and adjusts the ratio of congruent and incongruent trials accordingly to attain a desired difficulty curve.

The cue-induced craving was assessed by showing the participants images related to methamphetamine (methamphetamine crystals, powders, and paraphernalia) on a smartphone and asking them to rate their cravings on a 0-10 visual analog scale (0 being least craved and 10 being most craved).

The cue-induced craving was assessed by showing the participants images related to methamphetamine (methamphetamine crystals, powders, and paraphernalia) on a smartphone and asking them to rate their cravings on a 0-10 visual analog scale (0 being least craved and 10 being most craved).

The cue-induced craving was assessed by showing the participants images related to methamphetamine (methamphetamine crystals, powders, and paraphernalia) on a smartphone and asking them to rate their cravings on a 0-10 visual analog scale (0 being least craved and 10 being most craved).

Inclusion Criteria: • having a history of methamphetamine use of at least one year Exclusion Criteria: could not fluently operate an Android or an iOS smartphone having mental health conditions other than MUD