Regulation of Craving (ROC) Task

Introduction

The Regulation of Craving (ROC) task presents image stimuli of smoking that are rated for craving.

• Conditions: pictures of smoking
• Trial structure: Fixation cross (~1s), cue indicating look or reappraisal (2s), stimulus (5s), 1-5 rating (4s) => 12s/trial.

How to run the task

1. Launch the PsychoPy Builder.
2. Open the file ROC.psyexp.
3. Start the experiment by selecting the Tools -> Run menu item
4. Fill in the participant identifier, the session number and the run number. Session 0 is a brief practice run, session 1 and 2 with runs 1, 2, 3 or 4 are in-scanner runs. The task will start automatically after that.

The task is intended to be run using task_runner.

Task description

The task starts by displaying instruction text. The text is displayed until the trigger signal is received from the MRI, in the scanner version. In the scanner version the text is:

Calibrating scanner.

Trials are repeated 20 times in the scanner version.

Trial structure

1. Display a white fixation cross on a black background for ~1s in the behavioral version or for ~5s in the scanner version. The cross is 48 pixels square.
2. Display a cue of white text on black background, with a colored border for 2s. The cue is either the word LOOK or the word REGULATE. The border is colored green (RGB color in hexadecimal notation 0x00cd00) when the word LOOK is displayed, or is colored blue (0x0000ff) when the word REGULATE is displayed. The border starts at the outermost extent of the window and is 75 pixels wide.
3. Display the image stimulus for 5s, with the colored border described in step 2.
4. Display a rating scale, from 1 to 5, for 4s. The rating instructions, in white text on a black background, are

How much do you desire the
item shown in the last picture?

The rating scale has 1 labeled as No Desire and 5 labeled as Strong Desire.

Configuration

The task is configured by a CSV file that differs per participant, per session and per run:, ROC_<participant_id>_Session<session>_Run<run>.csv, i.e. ROC_ASH999_Session1_Run3.csv for the third run of the first session for participant ASH999. The CSV file must contain four columns: the duration in seconds the fixation cross is displayed (jitter_duration), the color of the border instructing look or regulate (background_color), the text to be displayed (reappraise_or_look), and the stimulus image to be displayed (image_file).

The location of the images is relative to the location of the ROC.psyexp task definition, and are currently stored in Resources/.