___________________________________________________________________________________________________________________ ATTENTION NETWORK TEST (ANT) - Adult Version ___________________________________________________________________________________________________________________ Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC Date: 02-21-2013 last updated: 02-16-2022 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC Script Copyright © 02-16-2022 Millisecond Software ___________________________________________________________________________________________________________________ BACKGROUND INFO ___________________________________________________________________________________________________________________ This script implements the Attention Network Test (ANT), a behavioral measure of alerting, orienting and executive attention. The implemented procedure is based on: Fan, J., McCandliss, B. D., Sommer, T., Raz, A., & Posner, M. I. (2002). Testing the efficiency and independence of attentional networks. Journal of Cognitive Neuroscience, 14, 340–347. The original ANT for adults and the child ANT as well as all stimuli used are generously shared by the original authors/Sackler Institute at: http://www.sacklerinstitute.org/cornell/assays_and_tools/ ___________________________________________________________________________________________________________________ TASK DESCRIPTION ___________________________________________________________________________________________________________________ Participants are presented arrows either directly above or below a fixation cross. Arrows may be flanked by other stimuli (3 flanker conditions). Participants have to decide whether the arrows point right or left. Several cue conditions (4) (may) alert the participants that the targets are about to come on screen and potentially where on the screen (above or below the fixation cross). Differences in mean reaction times in the different cue/flanker conditions are used to calculate the following three Attentional Network Effects: * Alert Effect: Effect of achieving and maintaining alertness * Orienting Effect: Effect of orienting attention towards a specific location of information * Conflict Effect: Effect of resolving conflict between several possible responses ___________________________________________________________________________________________________________________ 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: 'ant_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. blockcount: counts the number of experimental blocks run (custom counter) trialcount: counts the number of trials run in each block (resets after practice) (custom counter) cuecondition: the current cue condition (1 = no cue; 2 = center cue; 3 = double cue; 4 = spatial cue) flankercondition: the current flanker condition (1 = neutral; 2 = congruent; 3 = incongruent) targetposition: position of target relative to fixation (1 = above fixation; 2 = below fixation) targetdirection: the direction of the target (1 = right; 2 = left) picture.flanker1.currentItem/ picture.flanker4.currentItem: stores the images presented for targets and flankers Variables that contain y coordinates (vertical coordinates) for cues, targets, flankers: Note: coordinates are provided proportional to the canvas (Top = 0% - Bottom = 100%) target_y flanker1_y cue1_y response: the response of participant (scancode of response button: 18 = left E; 23 = right I; 57 = spacebar) correct: correctness of response (1 = correct, 0 = error) latency: response latency (in ms); measured from onset of target until response is made or trial times out (2) Summary data file: 'ant_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) overallpropcorrect: overall proportion correct across all testblock trials meanrt_correct: overall mean RT (of correct responses) for test trials Main Effects: propCorrect_noCue: proportion correct responses in nocue condition meanrt_noCue: mean response time (in ms) of correct responses in nocue condition propCorrect_centerCue: proportion correct responses in centercue condition meanrt_centerCue: mean response time (in ms) of correct responses in centercue condition propCorrect_doubleCue: proportion correct responses in doublecue condition meanrt_doubleCue: mean response time (in ms) of correct responses in doublecue condition propCorrect_spatialCue: proportion correct responses in spatialcue condition meanrt_spatialCue: mean response time (in ms) of correct responses in spatialcue condition propCorrect_congruent: proportion correct responses in trials with target-congruent flankers (flankers that point in the same direction as target) meanrt_congruent: mean response time (in ms) of correct responses in trials with target-congruent flankers (flankers that point in the same direction as target) propCorrect_incongruent: proportion correct responses in trials with target-incongruent flankers (flankers that point in the opposite direction as target) meanrt_incongruent: mean response time (in ms) of correct responses in trials with target-incongruent flankers (flankers that point in the opposite direction as target) propCorrect_neutral: proportion correct responses in trials with target-incongruent without flankers meanrt_neutral: mean response time (in ms) of correct responses in trials without flankers Interactions: propCorrect_congruentNC: proportion correct responses in trials with target-congruent flankers in No Cue Condition meanRT_correctCongruentNC: mean response time (in ms) of correct responses in trials with target-congruent flankers in No Cue Condition propCorrect_incongruentNC: proportion correct responses in trials with target-incongruent flankers in No Cue Condition meanRT_correctIncongruentNC: mean response time (in ms) of correct responses in trials with target-incongruent flankers in No Cue Condition propCorrect_neutralNC: proportion correct responses in neutral trials in No Cue Condition meanRT_correctNeutralNC: mean response time (in ms) of correct responses in in neutral trials in No Cue Condition (same for CC= center condition; DC = double cue condition; SC = spatial condition) Expressions that use above expressions and calculate the 3 attentional network effects (Fan et al, 2002, p.342/343) alertingeffect = meanrt_correctnocue - meanrt_correctdoublecue => Effect of achieving and maintaining alertness orientingeffect = meanrt_correctcentercue - meanrt_correctspatialcue => Effect of orienting attention towards a specific location of information conflicteffect = meanrt_correctincongruent - meanrt_correctcongruent => Effect of resolving conflict between several possible responses (executive function) ___________________________________________________________________________________________________________________ EXPERIMENTAL SET-UP ___________________________________________________________________________________________________________________ 4 cue conditions (no cue, center cue, double cue, spatial cue) x 3 flanker conditions (neutral, congruent, incongruent) within-subjects design A) 1 Block of 24 Practice trial sequences with full feedback, including summary feedback of speed and accuracy B) 3 Blocks of 96 trial sequences each - no feedback EXPERIMENTAL BLOCKS: 96 trial sequences: 2 (repetitions) x 4 (cue conditions) x 3 (flanker conditions) x 2 (target positions) x 2 (target directions) TRIAL SEQUENCE (one sequence for each cue condition) - randomly selected fixation (randomly chosen presentation time) -> cue (100ms) -> fixation (400ms) -> target (1700ms)-> intertrialinterval (depends: complete trialduration = 4s) ___________________________________________________________________________________________________________________ STIMULI ___________________________________________________________________________________________________________________ Size of Stimuli: Fan et al (2002) give specific dimensions of the size and distance of targets/flankers (p.345/346) => distance participant/screen: 65 cm => single line arrow : 0.55 degree visual angle => distance flankers/target: 0.06 degree visual angle (area covered by all: 3.08 degree visual angle) => distance target/fixation cross: 1.06 degree visual angle This script does NOT attempt to replicate these dimensions as different monitors require different fontsizes etc. Fine-tune fontsize of stimuli, distance of flanker to target, and position of target above and below fixation cross under section EDITABLE PARAMETERS ___________________________________________________________________________________________________________________ INSTRUCTIONS ___________________________________________________________________________________________________________________ Note: Instructions are modelled after the instructions generously made available on: http://www.sacklerinstitute.org/cornell/assays_and_tools/ 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: Stimuli Dimension/Placement: /fontsize_fixation: regulates the size of the fixation cross, in canvas height percentage (default: 5%) /cueSize: regulates the size of the cues, in canvas height percentage (default: 5%) /arrowsize: regulates the size of the target/flanker, in canvas height percentage (default: 6%) /flankerdistance: the relative screen distance between stimuli, in canvas width percentage (default: 7%) /top_y: the y-coordinate of the target above the fixation cross (default: 40%) /bottom_y: the y-coordinate of the target below the fixation cross (default: 60%) Trial Durations: /readyDuration: sets the duration (in ms) of the get-ready trial (default: 2000ms) /completetrial_duration: sets the complete duration of one trial sequence (default: 4000ms) /cue_duration: sets the duration of the cue presentation (default: 100ms) /fixation2_duration: sets the duration of the fixation cross after cue presentation (default: 400ms) /target_duration: sets the maximal duration of the target/flanker presentation (default: 1700ms) /practicefeedback_duration: sets the duration of the feedback trial during practice (default: 750ms) Response Keys: /responsekey_left: left response key (default: "E") /responsekey_right: right response key (default: "I")