In experiments 3 and 4, participants were presented with images representing natural rewards. On each trial, participants were first shown a fixation cross for 500 ms, followed by 250- to 500-ms jittered blank screen and then an image and instruction label for 6000 ms. In experiment 3, 32 natural reward trials were presented in a randomized event-related design to maximize sensitivity to detect the effects of conscious up-regulation (regulate > view) of neurophysiological responses to natural reward cues on a trial-by-trial basis. In experiment 4, two natural reward cue blocks (regulate versus view) each composed of 40 trials were presented in counterbalanced order.

Participants were instructed to view or regulate responses to stimuli. On view trials, participants were instructed to simply attend to images of naturally rewarding stimuli (e.g., social affiliation, natural beauty, and athletic victories) validated in previous studies (33). On regulate trials, to approximate mindful savoring techniques and conform with typical “increase positive” instructions on emotion regulation tasks (24), participants were instructed to imagine experiencing the positive event occurring in the image and to focus on enjoyable aspects of the image and their own positive emotional response to the image. As above, in a training session before EEG assessment, participants practiced this regulatory strategy and described their experience to a trained research assistant to ensure comprehension of the instructions. EEG assessment did not commence until participants could accurately describe implementation of regulatory instruction.

In experiment 4, at baseline and then after each task block, participants rated their current positive affective state from 1 (not positive at all) to 4 (extremely positive), as well as their current opioid craving from 1 (no craving) to 4 (extreme craving). Self-reported affect and craving ratings were skewed and subsequently log-transformed before analysis. Reactivity scores were computed by subtracting self-reported affect and craving ratings at baseline from ratings following task blocks. These reactivity scores were entered into RM-ANOVA models for analysis.

Note: The content above has been extracted from a research article, so it may not display correctly.

Please log in to submit your questions online.
Your question will be posted on the Bio-101 website. We will send your questions to the authors of this protocol and Bio-protocol community members who are experienced with this method. you will be informed using the email address associated with your Bio-protocol account.

We use cookies on this site to enhance your user experience. By using our website, you are agreeing to allow the storage of cookies on your computer.