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							ATTENTION NETWORK TEST (ANT) - Child Version


Script Author: Katja Borchert, Ph.D. ( for Millisecond Software, LLC
Date: 02-25-2013
last updated:  12-14-2018 by K. Borchert ( for Millisecond Software, LLC

Script Copyright ©  12-14-2018 Millisecond Software



This script implements the child version of the Attention Network Test (ANT) as described in:

Rueda, M. R., Fan, J., McCandlis, B. D., Halparin, J. D., Gruber, D. B., Pappert Lercari, L., & Posner, M.I (2004).
Development of attentional networks in childhood. Neuropsychologia, 42, 1029–1040.

The original ANT for adults was published in:

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:

Participants are presented a fish either directly above or below a fixation cross. The fish may be flanked by other 
fish  (3 flanker conditions). Participants have to decide whether the central fish's mouth points right or left. 
Several cue conditions (4)  (may) alert the participants that the fish is 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

The default data stored in the data files are:

(1) Raw data file: 'childANT_raw*.iqdat' (a separate file for each participant)

build:									Inquisit build version run
computer.platform:						the platform the script was run on
date, time, subject:					date and time script was run with the current subjectnumber 
/blockcount:							counts the number of experimental blocks run
blockcode:								the name and number of the current block
/trialcount:							counts the number of trials run (resets after practice)
trialcode: 								the name and number of the currently recorded trial
/cuecondition:							sets the current cue condition (1 = no cue; 2 = center cue; 3 = double cue; 4 = spatial cue)
/flankercondition:						sets the current flanker condition (1 = neutral; 2 = congruent; 3 = incongruent)
/targetposition:						sets position of target (1 = above fixation; 2 = below fixation)
/targetdirection:						sets the direction of the target (1 = right; 2 = left)
picture.flanker4.currenitem:			stores the items used as flanker1-flanker4

Variables that contain x/y coordinates for cues, targets, flankers

response:								the response of participant (scancode of response button: 18 = left; 23 = right)
correct:								correctness of response (1 = correct, 0 = error)
latency:								response latency (in ms)

(2) Summary data file: 'childANT_summary*.iqdat' (a separate file for each participant)

script.startdate:				date script was run
script.starttime:				time script was started
script.subjectid:				subject id number
script.groupid:					group id number
script.elapsedtime:				time it took to run script (in ms)
computer.platform:				the platform the script was run on
/completed:						0 = script was not completed (prematurely aborted); 1 = script was completed (all conditions run)
/overallpercentcorrect:			%correct across all testblock trials
/trialcount:					counts the number of trials run (resets after practice)
/meanRT_correct:				overall mean RT (of correct responses) for test trials
/medianRT_correct:				overall median RT (of correct responses) for test trials

Expressions that calcuate the mean reaction times (RT) for the different cue/flanker conditions based on latencies to correct responses
/meanRT_correctNoCue -
/meanRT_correct_InCongruentNoCue (Interaction scores)

Expressions that calcuate the median reaction times (RT) for the different cue/flanker conditions based on latencies to correct responses
/medianRT_correctNoCue -
/medianRT_correct_InCongruentNoCue (Interaction scores) 

Expressions that calculate error percentages for the 12 separate 3 (flanker type) x 4 (cue type) cells. 
See Rueda et al. (2004), Table 1.
/pct_errorCongruent_NoCue -

Expressions that use above expressions and calculate the 3 attentional network effects 
based on median RTs (Rueda et al, 2004)

/AlertingEffect = expressions.medianrt_correctnocue - expressions.medianrt_correctdoublecue
/OrientingEffect = expressions.medianrt_correctcentercue - expressions.medianrt_correctspatialcue
/ConflictEffect = expressions.medianrt_correctincongruent - expressions.medianrt_correctcongruent

!Note: earlier versions of this script calculated the 3 effects based on mean RTs (as done by Fan et al, 2002)
meanbased Effects are also stored in the summary file

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 feedback,
B) 3 Blocks of 48 trial sequences each - feedback optional (default: with feedback, Editable Values -> parameters.experimentalfeedback)
	48 trial sequences: 1 (repetition) x 4 (cue conditions) x 3 (flanker conditions) x 2 (target positions) x 2 (target directions) - order randomly determined
	TRIAL SEQUENCES (one sequence for each cue condition)
	fixation (randomly chosen presentation time) -> cue (100ms) -> fixation (400ms) -> target (1700ms)-> intertrialinterval (1000ms)

Type of Stimuli
* The fish stimuli are taken from
* Stimuli can easily be edited under section EDITABLE STIMULI
* This script uses a simple black dot as the cue as opposed to a * (see Rueda et al (2004))

Size of Stimuli:
Rueda et al (2004) give specific dimensions of the size and distance of targets/flankers (p.1031) for the adult version
	=> distance participant/screen: about 53cm
	=> single fish: each fish covered 1.6◦ of visual angle
	=> flanker/target distance: adjacent fish were separated by 0.21◦
	=> distance target/fixation: target fish was presented about 1◦ above or below +

This script does NOT attempt to replicate these dimensions as different monitors require different fontsizes etc.
Fine-tune sizes of stimuli, distance of flanker to target, and position of target above and below 
fixation cross under section EDITABLE values

Instruction Slides are included in the zip file for this script (childANT_instructions.pptx)
and can easily be customized in PowerPoint or Google Slides.
These instructions are not original but are modelled after instructions published on

Note: The instructions slide were downloaded from Google Slides as "file -> download as- >scalable vector graphics (*.svg)"
and are presented in this script by html-elements. They automatically scale to the size of the current monitor.

check under EDITABLE CODE below for (relatively) easily editable values, 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 values you can change are:

Stimuli Dimension/Placement:
/fontsize_fixation:						regulates the size of the fixation cross, canvas height % (default:  3%)
/fontsize_cue:							regulates the size of the cue, canvas height %  (default: 5%)
/flankerdistance:						the relative screen distance between stimuli, canvas width %  (default: 5%)
/top_y:									the y-coordinate of the target above the fixation cross, canvas height %  (default: 40%)
/bottom_y:								the y-coordinate of the target below the fixation cross, canvas height %  (default: 60%)

Trial Durations:
/cue_duration:							sets the duration of the cue presentation (default: 150ms)
/fixation2_duration:					sets the duration of the fixation cross after cue presentation (default: 450ms)
/feedback_duration:						sets the duration of the feedback trial (default: 2000ms)
/ITI_practice:							sets the duration of trial.ITI (default: 1000ms)

Response Keys:
/responsekey_left:						scancode for the left response key (default: "E", 18)
/responsekey_right:						scancode for the right response key (default: "I", 23)

/experimentalfeedback:					1= feedback only during practice; 2 = feedback for experimental trials also (default)

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