Return to the Child Flanker Test with Fish page
						
									CHILD FLANKER TEST
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 02-25-2014
last updated: 08-03-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Copyright © 08-03-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script implements a basic Flanker Test for children as described in:

Christ, S.E., Kester, L.E., Bodner, K.E. & Miles, J.H. (2011). Evidence for Selective Inhibitory Impairment in Individuals 
With Autism Spectrum Disorder. Neuropsychology, 25, 690–701.


											  *Task*
Participants are presented 5 fish in one row and are instructed to pay attention to the center fish (target).
If the center fish looks to the right, participants are instructed to press a specific response key.
If the center fish looks to the left, participants are instructed to press a different response key.
The fish flanking the middle fish (the flankers) can either look in the same (compatible) or the 
opposite direction (incompatible) than the target/center fish (Note: the flanker fish always look in the same direction).


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

(1) Raw data file: 'ChildFlankerFish_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 
blockcode, blocknum:			the name and number of the current block
trialcode, trialnum: 			the name and number of the currently recorded trial
									(Note: not all trials that are run might record data) 
/trialtype:						1 = congruent, target fish to the right
								2 = incongruent, target fish to the right
								3 = congruent, target fish to the left
								4 = incongruent, target fish to the left
/congruence:					stores the congruence of the target and flankers (congruent vs incongruent)
/targetdirection:				stores the direction of the target fish (targetleft vs targetright)
stimulusitem:					the presented stimuli in order of trial presentation
response:						the participant's response (scancode)
/response:						stores the response category depending on latency and response key used ("anticipatory", "valid", "too slow", "wrong response")
correct:						the correctness of the response
latency: 						the response latency in ms

(2) Summary data file: 'ChildFlankerFish_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; 1 = script was completed (all conditions run)

/percenterrors_c:  				percent errors in congruent trials (test only)
/percenterrors_i:				percent errors in incongruent trials (test only)
/meanRT_cc:						mean latency of correct responses in congruent trials (in ms)
/meanRT_ci:						mean latency of correct responses in incongruent trials (in ms)


EXPERIMENTAL SET-UP
2 congruence (congruent vs incongruent) x 2 target directions (right vs left) tested within participants

1. Practice Block: 20 trials with only targets (10 left, 10 right, randomly sampled)
2. Practice Block: 20 trials with targets and flankers (5 congruent_left, 5 congruent_right, 5 incongruent_right, 5 incongruent_left,
randomly sampled)
3. Test Block: 120 trials with targets and flankers (all 4 conditions equally often, randomly sampled)
=> number of trials can be edited under EDITABLE CODE -> Editable Values

Trial Sequence:
1. trial.flanker: trialduration max. 3000ms (default, editable) 
-> trial terminates immediately after a given response or after max trialduration.

!!Note: to adjust the size of the 5 fish on your monitor, go to EDITABLE CODE -> Editable Values and edit
parameters.pictureheight and/or parameters.flankerdistance

2. (trial.errorfeedback): if errors occurred; error trialduration editable
	Errors:
	a) Anticipatory response: responses faster than parameters.anticipatoryresponselatency (default: 200ms, editable value)
	b) Too slow: no response occuring before parameters.max_trialduration (default: 3000ms = max trialduration of trial.flanker, editable value)
	c) Wrong Response: incorrect response key was pressed

	Error feedback is presented in a visual (text that specifies the specific error) and auditory form (sound file).

3. trial.iti: trialduration 1500ms  (default, editable)
4. (trial.rest): if number of trials indicate that a rest trial should be presented (default: after 40 trials, editable)

STIMULI
Fish stimuli are used from the ChildANT.iqx script (the fish were originally downloaded from:
http://www.sacklerinstitute.org/cornell/assays_and_tools/)

INSTRUCTIONS
Instructions are not original. They can easily be edited under EDITABLE CODE -> 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:

Responsekeys:
/responsekey_targetright:						scancode of the response key for target fish that look to the right (default: 52)
/responsekeytargetright_label:					description of the response key for target fish that look to the right
/responsekey_targetleft:						scancode of the response key for target fish that look to the left (default: 51)
/responsekeytargetleft_label:					description of the response key for target fish that look to the left

Fish presentation:
/pictureheight:									determines the size/height in screen height % of the individual fish pictures (default: 10%)
/flankerdistance:								determines the distance in screen width % between flankers (default: 10%)
													Note: change these parameters to optimize the fish presentation on your screen

/errorfeedbackheight:							determines the height of the feedback text in screen height (default: 5%)

Trialnumbers:
/numberofpracticetrials:						determines the number of practice trials in each practice blocks (default: 20)
/numberoftrials:								determines the number of test trials (default: 120)
													Note: list.trialtype controls the distribution of congruent/incongruent trials
													by default, the same number of congruent right, incongruent right, congruent left, incongruent left
													trials are run.
/resttrial:										determines the number of trials after which a rest trial is presented

Trialdurations:
/max_trialduration:								the maximum trial duration of the flanker presentation in ms (default: 3000ms)
/iti:											the duration of the intertrial interval in ms- time between response and next presentation
												OR time between offset of errorfeedback and next presentation (default: 1500ms)
/errorfeedbackduration:							duration of error feedback in ms (default: 1000ms)
/restduration:									duration of rest trial in ms(default: 60000ms)

/anticipatoryresponselatency:					all response latencies (in ms) lower than this value will be categorized as "anticipatory responses" (default: 200ms)

Copyright © Millisecond Software. All rights reserved.
Contact | Terms of Service | Security Statement | Employment