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							STIMULUS RESPONSE COMPATIBILITY TASK (SRCT)
SCRIPT INFO

Script Author: original Inquisit script written by Barkby et al (2012)
last updated: 08-18-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC


BACKGROUND INFO

											*Purpose*
This script implements the Stimulus Response Compatibility Task (SRCT) as described in 

Barkby, H., Dickson, J.M., Roper, L., & Field, M. (2012). To Approach or Avoid Alcohol? Automatic and Self-
Reported Motivational Tendencies in Alcohol Dependence. Alcoholism: Clinical and Experimental Research, 36, 
361-368.

Millisecond Software LLC thanks Dr. Matt Field for generously providing the original scripts as well
as the original stimuli!

											  *Task*
Participants are presented with either an alcohol-related picture or a control picture. 
Depending on instructions, they are asked to press the arrow keys of the numeric
key pad (default, can be changed under EDITABLE VALUES) so as to move a manikin,
that is either presented above (top) or below (bottom) the picture,  towards (or away) from the alcohol related 
pictures and away (towards) the control pictures.


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

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

build:							Inquisit build
computer.platform:				the platform the script was run on
date, time, subject, group:		date and time script was run with the current subject/groupnumber 
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; by default data is collected unless /recorddata = false is set for a particular trial/block) 
/responsekey_up = 21			default scancode for the up-key (key "Y")
/responsekey_down = 48			default scancode for the down-key (key "B")
/responsekey_left = 33			default scancode for the left-key (key "F")
/responsekey_right = 36			default scancode for the right-key (key "J")
/expcondition:					6 experimental conditions; subject assignment by groupnumber
								Experiment runs 3 main blocks (block.main_approach_alc, block.main_avoid_alc, block.main_left_alc/block.main_right_alc).
								The order of the 3 main blocks is counterbalanced across participants. 
								Furthermore, half the participants in each counterbalanced condition run block.main_right_alc, the other half
								run block.main_left_alc => 6 conditions
/stimulus:						contains the name of the picture image
response:						the participant's response
correct:						the correctness of the response (1 = correct; 0 = incorrect)
latency: 						the response latency (in ms)

(2) Summary data file: 'SRCT_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)
/expcondition:					6 experimental conditions; subject assignment by groupnumber
								Experiment runs 3 main blocks (block.main_approach_alc, block.main_avoid_alc, block.main_left_alc/block.main_right_alc).
								The order of the 3 main blocks is counterbalanced across participants. 
								Furthermore, half the participants in each counterbalanced condition run block.main_right_alc, the other half
								run block.main_left_alc => 6 conditions
/propcorr_total:				overall proportion correct (test trials only)
/meanRT_total:					overall mean latency (in ms) of correct test trials
/propcorr_AlcApproach:			proportion correct Alcohol Approach test trials
/meanRT_AlcApproach:			mean latency (in ms) of correct Alcohol Approach test trials
/propcorr_AlcAvoid:				proportion correct Alcohol Avoid test trials
/meanRT_AlcAvoid:				mean latency (in ms) of correct Alcohol Avoid test trials
/propcorr_CtrlApproach:			proportion correct Control Approach test trials
/meanRT_CtrlApproach:			mean latency (in ms) of correct Control Approach test trials
/propcorr_CtrlAvoid:			proportion correct Control Avoid test trials
/meanRT_CtrlAvoid:				mean latency (in ms) of correct Control Avoid test trials
/propcorr_AlcLeft:				proportion correct Alcohol Left test trials
/meanRT_AlcLeft:				mean latency (in ms) of correct Alcohol Left test trials
/propcorr_AlcRight:				proportion correct Alcohol Right test trials
/meanRT_AlcRight:				mean latency (in ms) of correct Alcohol Right test trials
/propcorr_CtrlLeft:				proportion correct Control Left test trials
/meanRT_CtrlLeft:				mean latency (in ms) of correct Control Left test trials
/propcorr_CtrlRight:			proportion correct Control Right test trials
/meanRT_CtrlRight:				mean latency (in ms) of correct Control Right test trials


EXPERIMENTAL SET-UP

Experiment runs 3 main blocks (block.main_approach_alc, block.main_avoid_alc, block.main_left_alc/block.main_right_alc).
The order of the 3 main blocks is counterbalanced across participants. 
Furthermore, half the participants in each counterbalanced condition run block.main_right_alc, the other half
run block.main_left_alc.
=> 6 experimental conditions, assignment by groupnumber (default, can be changed under EXPERIMENT)

Blocks:
1. block.main_approach_alc: move the manikin towards alcohol related pictures and away from control pictures
(in half the trials manikin is on top, in the other half the manikin is on the bottom)
2. block.main_avoid_alc: move the manikin away from alcohol related pictures and towards control pictures
(in half the trials manikin is on top, in the other half the manikin is on the bottom)
3a. block.main_left_alc: move the manikin to the left for alcholo related pictures and to the right for control pictures
(in half the trials manikin is on top, in the other half the manikin is on the bottom)
3b. block.main_right_alc: move the manikin to the right for alcholo related pictures and to the left for control pictures
(in half the trials manikin is on top, in the other half the manikin is on the bottom)

Each main block has 8 practice trials and 2 x 28 experimental trials (= 2 subblocks). For each subblock of each main block (e.g. block.main_approach_alc) 
the type of trial is randomly sampled  from the four corresponding trials (e.g. trial.alcapproach_manikintop, trial.alcapproach_manikinbottom, trial.ctrlavoid_manikinbottom, trial.ctrlavoid_manikintop) 
without replacement => 14 alcohol images and 14 control images are shown, 7 of each with the manikin on top and 7 with the manikin on the bottom.
Over the course of the 2 x 28 trials (= 2 subblocks), each picture appears twice (once in the first subblock, once in the second subblock), 
once with the manikin on top and once with the manikin on the bottom. 

Trials:
* A blank screen is shown for 1000ms, followed by the alcholol-related or control picture with a manikin on top or on the bottom
* a correct response is followed by showing a video of the manikin moving in the correct direction (duration: 1000ms)
* an incorrect response is followed by a red "X" in the middle of the screen (duration: 1000ms)

INSTRUCTIONS:
Instructions are the originals. To edit go to section Editable Instructions.

STIMULI
14 alcohol related and 14 control pictures. 

!!! NOTE: The stimuli are culturally specific and may not work for a study outside the intended culture. 
To use your own images go to Editable Stimuli-> item.alcoholpics and item.controlpics
and substitute your own.

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:

/responsekey_up = 21				default scancode for the up-key (key "Y")
/responsekey_down = 48				default scancode for the down-key (key "B")
/responsekey_left = 33				default scancode for the left-key (key "F")
/responsekey_right = 36				default scancode for the right-key (key "J")
/upkeylabel = "Y"					default label for the up key (used in instructions)
/downkeylabel = "B"					default label for the down key (used in instructions)
/leftkeylabel = "F"					default label for the left key (used in instructions)
/rightkeylabel = "J"				default label for the right key (used in instructions)

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