___________________________________________________________________________________________________________________ *Progressive Ratio Button Press Task* (Miras Procedure) (German instructions) ___________________________________________________________________________________________________________________ Script Author: Katja Borchert, Ph.D. (seandr@millisecond.com) for Millisecond Software, LLC Date: 06-14-2023 last updated: 06-14-2023 by K. Borchert (seandr@millisecond.com) for Millisecond Software, LLC Script Copyright © 02-25-2022 Millisecond Software German translation provided by K. Borchert for Millisecond Software ___________________________________________________________________________________________________________________ BACKGROUND INFO ___________________________________________________________________________________________________________________ This script implements a 'Progressive Ratio Button Press Task' to determine the "breakpoint" at which the reward (food) is no longer worth the effort of clicking a mouse button. The implemented template is based on the procedure described by Miras et (2012). Reference: Miras AD, Jackson RN, Jackson SN, Goldstone AP, Olbers T, Hackenberg T, Spector AC, le Roux CW. Gastric bypass surgery for obesity decreases the reward value of a sweet-fat stimulus as assessed in a progressive ratio task. Am J Clin Nutr. 2012 Sep;96(3):467-73. doi: 10.3945/ajcn.112.036921. Epub 2012 Jul 25. PMID: 22836034. ___________________________________________________________________________________________________________________ TASK DESCRIPTION ___________________________________________________________________________________________________________________ Participants are instructed to repeatedly click the left mouse button for rewards. When they no longer wish to click the mouse button, they can press a spacebard to end the task. The number of clicks required to receive a reward is increased by a multiple (2 by default) with each round. The task continues until the participant opts out by pressing the space bar. The number of clicks in the last completed round is considered the "breakpoint" after which the reward is no longer worth the effort. ___________________________________________________________________________________________________________________ DURATION ___________________________________________________________________________________________________________________ The duration of the script varies depending on the particpant's perserverance. ___________________________________________________________________________________________________________________ DATA FILE INFORMATION ___________________________________________________________________________________________________________________ The default data stored in the data files are: (1) Raw data file: 'progressiveratio_miras_raw*.iqdat' (a separate file for each participant)* build: The specific Inquisit version used (the 'build') that was run computer.platform: the platform the script was run on (win/mac/ios/android) date, time: date and time script was run subject, group: with the current subject/groupnumber session: with the current session id blockcode, blocknum: the name and number of the current block (built-in Inquisit variable) trialcode, trialnum: the name and number of the currently recorded trial (built-in Inquisit variable) Note: trialnum is a built-in Inquisit variable; it counts all trials run; even those that do not store data to the data file. response: the response given latency: response time in milliseconds. roundCount: Total number of rounds excluding the practice round clickCount: Total number of mouse clicks excluding the practice round currentRatio: Number of clicks required to complete the current round (2) Summary data file: 'progressiveratio_miras_summary*.iqdat' (a separate file for each participant)* inquisit.version: Inquisit version run computer.platform: the platform the script was run on (win/mac/ios/android) startDate: date script was run startTime: time script was started subjectid: assigned subject id number groupid: assigned group id number sessionid: assigned session id number elapsedTime: time it took to run script (in ms); measured from onset to offset of script completed: 0 = script was not completed (prematurely aborted); 1 = script was completed (all conditions run) startingRatio: The total clicks for the first round geometricIncrement: The factor by which the number of clicks per round is multiplied breakPoint: The total clicks for the last completed round roundsCount: The total number of completed rounds excluding practice rounds clickCount: The total number of clicks excluding practice rounds ___________________________________________________________________________________________________________________ EXPERIMENTAL SET UP ___________________________________________________________________________________________________________________ Trial Sequence: - A practice round is run at the beginning with parameters.startingRatio as the required number of clicks. - The practice round is followed by test rounds until the participant presses SHIFT+SPACE to quit. - As participants complete each test round, they are shown a screen indicating they will receive a reward. The number of clicks required to complete the next round is multiplied by parameters.geometricIncrement. - The task continues with progressively longer rounds until the participant opts out by pressing the SHIFT+SPACE ___________________________________________________________________________________________________________________ STIMULI ___________________________________________________________________________________________________________________ The task presents instructions but does not otherwise present any stimuli. ___________________________________________________________________________________________________________________ INSTRUCTIONS ___________________________________________________________________________________________________________________ provided by Millisecond Software - can be edited under section Editable Instructions ___________________________________________________________________________________________________________________ EDITABLE CODE ___________________________________________________________________________________________________________________ check below for (relatively) easily editable parameters, stimuli, instructions etc. Keep in mind that you can use this script as a template and therefore always "mess" with the entire code to further customize your experiment.