The value affirmation task presents text stimuli, related to a participant's values, to affect how people consider quitting smoking. This task is used in the Rethink Smoking study.

• Conditions: The value that is important to the participant or and the value that is least important.
• Trial structure: Introduction text (4s). Then text related to a value (6s), then text "How helpful is this message to help you quit smoking?" that requires a rating response (4s), then an intertrial interval (~2s), repeated 20 times. 12s per trial.
• Duration: 20 trials = 240s total.

The task is run using PsychoPy. 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.

The task consists of displaying text related to quitting smoking that involves the participant's self-selected most important and least important values. Introduction text is displayed for 4s. The introduction text is

Calibrating scanner

Next text related to each value is presented for 6s. Then the text "How helpful is this message to help you quit smoking?" is displayed and a rating scale is also displayed (4s). The rating scale has five possible responses on the scale, 1-5, with labels at the ends

1 = not at all
5 = extremely

The participant uses the 1, 2, 3, 4, or 5 buttons on the keyboard to respond. Then there is a blank intertrial interval, jittered mean 2s.

The trials are repeated 20 times.

The task is configured by a CSV file that differs per participant, per session and per run: VAFF_<participant_id>_Session<session>_Run<run>.csv, i.e. VAFF_ASH999_Session1_Run3.csv for the third run of the first session for participant ASH999. The CSV file must contain two columns: the message to be displayed (message) and the duration in seconds of the inter-trial interval (iti).