___________________________________________________________________________________________________________________ Food GO-NOGO TASK ___________________________________________________________________________________________________________________ Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC Date: 02-21-2017 last updated: 10-04-2024 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC Script Copyright © 10-04-2024 Millisecond Software Millisecond Software thanks Dr. John Gunstad for his help with this script! ___________________________________________________________________________________________________________________ BACKGROUND INFO ___________________________________________________________________________________________________________________ Go/Nogo Tasks are used as behavioral measures of inhibition and cognitive control. The Food Go/No Tasks leverages this paradigm to investigate cognitive control in the context of food. Teslovich, T. et al (2014). Probing behavioral responses to food: Development of a foodspecific go/no-go task. Psychiatry Res, 30, 219(1): 166–170. E-prime script available at: http://fablab.yale.edu/page/assays-tools ___________________________________________________________________________________________________________________ TASK DESCRIPTION ___________________________________________________________________________________________________________________ Go-Nogo task: general task is to press the spacebar whenever an stimuli of the Go category (e.g. food images) is presented and refrain from responding whenever a stimuli of the NoGo category (e.g. toys) is presented. In this script, participants work through 4 conditions: (1) high-calorie food “go” with toy “no-go” (2) low-calorie food “go” with toy “no-go” (3) toy “go” with high-calorie food “no-go” (4) toy “go” with low-calorie food “no-go” Each condition runs ~75% go trials (35) and ~25% (13) nogo trials. ___________________________________________________________________________________________________________________ DURATION ___________________________________________________________________________________________________________________ the default set-up of the script takes appr. 20 minutes to complete ___________________________________________________________________________________________________________________ DATA FILE INFORMATION ___________________________________________________________________________________________________________________ The default data stored in the data files are: (1) Raw data file: 'foodgonogo_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 such as feedback trials. Thus, trialnum may not reflect the number of main trials run per block. order: the order in which the four test blocks were run calorieType: "high" vs. "low" vs. "ctrl" goType: "go" vs. "nogo" ITI: current intertrial interval in ms stim: stores the currently presented target picture response: the participant's response (scancode of response button) Spacebar: 57 no response: 0 correct: the correctness of the response (1 = correct; 0 = otherwise) latency: the response latency (in ms); measured from onset of image until response is registered (2) Summary data file: 'foodgonogo_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) order: the order in which the four test blocks were run propCorrect: overall proportion correct across all trials meanRT: mean correct reaction times across all GO trials sd: standard deviation of correct reaction times in GO trials maxRT: reaction time that is 3 standard deviations slower than the overall mean minRT: reaction time that is 3 standard deviations faster than the overall mean /////////////// food: /////////////// hitRateFood: hit rate in food GO trials (across low and high calorie food) omissionFood: miss rate in food GO trials (should have responded to food but did not) commissionFood: false alarm rate in food (across low and high calorie food) NOGO trials (should NOT have responded to food but did) Note: => the higher the commission rate, the lower cognitive control in the face of food stimuli (aka cannot refrain from responding) corrRejectRateFood: correct rejection Rate in food NOGO trials (correctly suppressed response to food nogo trials) meanRTFoodOrig: mean hit reaction time (in ms) in food GO trials (no outliers removed) meanRTFoodCleaned: mean hit reaction time (in ms) in food GO trials (outliers removed*) + separate variables a) HC: high calorie (HC) food b) LC: low calorie (HC) food /////////////// Ctrl (Toys) /////////////// hitRateCtrl: hit rate in ctrl GO trials (across blocks when toys were paired with low calorie OR high calorie nogo trials) omissionCtrl: miss rate in ctrl GO trials (should have responded to toys but did not) commissionCtrl: false alarm rate in ctrl NOGO trials (should NOT have responded to toys but did) corrRejectRateCtrl: correct rejection Rate in ctrl NOGO trials (correctly suppressed response to toys nogo trials) meanRTCtrlOrig: mean hit reaction time (in ms) in ctrl GO trials (no outliers removed) meanRTCtrlCleaned: mean hit reaction time (in ms) in ctrl GO trials (outliers removed*) + separate variables a) CtrlHC: toys when run in the same block as high calorie (HC) food (both as signals and as noise) b) CtrlLC: toys when run in the same block as low calorie (HC) food (both as signals and as noise) ////////////////////////////////// Signal Detection Measures ////////////////////////////////// Note: *Adjustments to z-scores as recommended by: Gregg, A. & Sedikides, C. (2010). Narcissistic Fragility: Rethinking Its Links to Explicit and Implicit Self-esteem, Self and Identity, 9:2, 142-161 (p.148) => Adjustments are made if the FArate (hitRate) = 0 (increased to 0.005) or 1 (decreased to 0.995)* //////////////////////////////// signal: High Calorie Food noise: Toys //////////////////////////////// zHitRateHC: z-value of the hit rate with signal = HCfood and noise = toys zFARateHC: z-value of the false alarm rate with signal = HCfood and noise = toys dPrimeHC: Computes d' (parametric measure of discriminability btw. signals and noise) => Range (in this script): -5.1516586840152740479 <= dprime <= 5.1516586840152740479 (=perfect performance) => The higher the value, the better signals (HC food stims) were distinguished from noise (toys) (d' = 0: chance performance; negative d-primes: participant treated nontargets as targets and targets as nontargets) cHC: c-criterion in signal detection:The absolute value of c provides an indication of the strength of the response bias/response style negative: participant more likely to report that signal (HC food stims) is present (liberal response style); may favor faster responding in speed-accuracy trade-off response paradigms positive: favoring caution (conservative response style) same for: LC (signal: Low Calorie Food; Noise: Toys) same for: CtrlHC (signal: Toys; Noise: High Calorie Food) same for: CtrlLC (signal: Toys; Noise: Low Calorie Food) * separate data files: to change to one data file for all participants (on Inquisit Lab only), go to section "DATA" and follow further instructions ___________________________________________________________________________________________________________________ EXPERIMENTAL SET-UP ___________________________________________________________________________________________________________________ (I) Practice: ~3min practice session with a) Food (high and low calorie) Go / Toy Nogo and b) Food Nogo / Toys Go Total practice trials: 22; trial/stimuli order fixed (see http://fablab.yale.edu/page/assays-tools) (II) Test: 4 conditions tested: (1) high-calorie food “go” with toy “no-go” (block.highGO, 48 trials: 35 go trials, 13 nogo trials) (2) low-calorie food “go” with toy “no-go”, (block.lowGO) (3) toy “go” with high-calorie food “no-go”, (block.highNOGO) (4) toy “go” with low-calorie food “no-go”, (block.lowNOGO) tested within participants in a blocked format. The order of the 4 conditions were counterbalanced by groupnumbers (4 orders, see section EXPERIMENT). Each block runs 35 go trials and 13 nogo trials (= 4 x 48 test trials = 192 test trials total) By default all blocks run trials/stimuli in a fixed order. Orders taken from: http://fablab.yale.edu/page/assays-tools To run the trials/stimuli in random order, go to section Editable Lists and follow further instructions. Default Trial Timings: Fixation Cross (ITI duration: either fixed or random*) -> Target Image (500ms) -> Fixation Cross until response or up to 2000ms (End of Trial) * if parameters.runRandomITI is set to false, a fixed ITI is run. Default is: 2500ms (can be set under section Editable Parameters). Random ITIs are controlled by list.intertrialIntervals under section Editable Lists. **Each block starts with a trial that presents the fixation cross in red for 500ms ___________________________________________________________________________________________________________________ STIMULI ___________________________________________________________________________________________________________________ Stimuli used provided by: http://fablab.yale.edu/page/assays-tools ___________________________________________________________________________________________________________________ INSTRUCTIONS ___________________________________________________________________________________________________________________ instructions modelled after instructions used by: http://fablab.yale.edu/page/assays-tools all instructions 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. The parameters you can change are: