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								SHORT ATTENTION NETWORK TEST (short ANT) - Adult Version

SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date:	02-21-2013
last updated:  03-05-2018 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Copyright ©  03-05-2018 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script implements the short Attention Network Test (shortANT) as shared by Dr. Fan:
http://people.qc.cuny.edu/Faculty/Jin.Fan/Pages/Downloads.aspx


the original ANT 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.


											  *Task*
Participants are presented arrows either directly above or below a fixation cross. Arrows are flanked by other 
arrows that point in the same (congruent) or opposite direction (incongruent).
Participants have to decide whether the central arrows point right or left. 
Several cue conditions (3)  (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).



DATA FILE INFORMATION: 
The default data stored in the data files are:

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

build:									Inquisit build
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
/completetrialDuration:					the complete duration (in ms) of one trial sequence (default: 4000ms)
/fixation1_duration:					duration (in ms) of first fixation cross
/cue_duration:							the duration (in ms) of the cue presentation (default: 100ms)
/ISI_cuetarget:							the duration (in ms) of the fixation cross after cue presentation and before target (default: 400ms)
/target_duration:						the maximal duration (in ms) of the target/flanker presentation (default: 1700ms)
										Note: equals the response window
/ITI_duration:							the duration (in ms) of the intertrial duration
										Note: the intertrialduration is calculated by subtracting the duration of the main trials (e. trial.centercue)
										from parameters.completetrialDuration

/cuecondition:							sets the current cue condition (1 = no cue; 2 = center cue; 3 = spatial cue)
/flankercongruence:						sets the current flanker condition (1 = congruent; 2 = incongruent)
/targetposition:						sets position of target (1 = above fixation; 2 = below fixation)
/targetdirection:						sets the direction of the target (1 = right; 2 = left)
text.flanker1.currentitem-
text.flanker4.currenitem:				stores the items used as flanker1-flanker4 (as well as for the target)
text.target.currentitemnumber:			stores the itemnumber of the currently presented target

Variables that contain x/y coordinates for cues, targets, flankers:
/target_x
/target_y
/flanker1_x
/flanker1_y
/cue1_x
/cue1_y

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); measured from onset of targets/flanker


(2) Summary data file: 'shortANT_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)
		
/ACCoverall:					%correct across all testblock trials
/meanRT_correct:				overall mean RT (of correct responses) for test trials

/ACCnocue:						%correct in nocue trials
/ACCcentercue:					%correct in centercue trials
/ACCspatialcue:					%correct in spatialcue trials

/meanRT_correctNoCue:			mean correct latency (in ms) in no cue condition
/meanRT_correctCenterCue:		mean correct latency (in ms) in center condition
/meanRT_correctSpatialCue:		mean correct latency (in ms) in nospatial condition

/ACCcongruent:					%correct in congruent trials
/ACCincongruent:				%correct in incongruent trials

/meanRT_correctCongruent:		mean correct latency (in ms) in congruent trials
/meanRT_correctInCongruent:		mean correct latency (in ms) in incongruent trials

Expressions that use above expressions and calculate 2 attentional network effects (Fan et al, 2002, p.342/343)
/OrientingEffect = expressions.meanrt_correctcentercue - expressions.meanrt_correctspatialcue => Effect of orienting attention towards a specific location of information
/ConflictEffect = expressions.meanrt_correctincongruent - expressions.meanrt_correctcongruent => Effect of resolving conflict between several possible responses


EXPERIMENTAL SET-UP
3 cue conditions (no cue, center cue, spatial cue) x 2 flanker conditions (congruent, incongruent)
within-subjects design

A) 1 Block of 12 Practice trial sequences with feedback
B) 1 Blocks of 120 trial sequences each - no feedback
	EXPERIMENTAL BLOCKS:
	120 trial sequences: 5 (repetitions) x 3 (cue conditions) x 2 (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: 400ms +) -> cue (100ms) -> fixation (400ms) -> target (1700ms)-> intertrialinterval (depends: complete trialduration = 4s)



STIMULI
A) Type of Stimuli: This script uses a simple black dot as the cue as opposed to a * (see Fan et al (2002))

B) 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 by Dr. Fan
Instructions can be edited under section EDITABLE INSTRUCTIONS

EDITABLE CODE:
check under EDITABLE CODE 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:  3%)
/fontsize_cue:							regulates the size of the cues, in canvas height percentage (default: 5%)
/fontsize_target:						regulates the size of the target/flanker, in canvas height percentage (default: 5%)
/flankerdistance:						the relative screen distance between stimuli, in canvas width percentage (default: 5%)
/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:
/completetrialDuration:					sets the complete duration (in ms) of one trial sequence (default: 4000ms)
/minfixation1_duration:					sets the minimum duration (in ms) of the first fixation cross in a trial sequence. The actual duration
										contains the addition of a random component: a randomly selected number between 0-1200ms is added to 
										this fixation duration. (default: 400ms)
/cue_duration:							sets the duration (in ms) of the cue presentation (default: 100ms)
/ISI_cuetarget:							sets the duration (in ms) of the fixation cross after cue presentation and before target (default: 400ms)
/target_duration:						sets the maximal duration (in ms) of the target/flanker presentation (default: 1700ms)
										Note: equals the response window
/practicefeedback_duration:				sets the duration (in ms) of the feedback trial during practice (default: 2000ms)

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


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