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									INSPECTION TIME TASK
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 12-05-2014

last updated: 08-15-2016 by K.Borchert for Millisecond Software LLC

Copyright © 08-15-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script runs an Inspection Time task similar to the one described by:

Deary, I.J., Enrico Simonotto, E., Meyer, M., Marshall, A., Ian Marshall, I., Goddard, N. & Wardlawf, J.M. (2004).
The functional anatomy of inspection time: an event-related fMRI study. NeuroImage, 22, 1466– 1479.

											  *Task*
Participants see stimuli that have one long and one short arm. The stimuli are presented for variable
durations before they are covered by a mask. Participants have to decide whether the short arm
was left or right and press corresponding response keys.
Participants are told that reaction time is unimportant.



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

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

build:							Inquisit build
computer.platform:				the platform the script was run on
display.refreshrate:			the vertical refresh rate of the current monitor 
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) 
/stimduration:					duration (in ms) of current stim
/stimduration_condition:		1-15 (depending on stimduration)
/location:						1 = left shorter arm; 2 = right shorter arm
stimulusitem:					the presented stimuli in order of trial presentation
response:						the participant's response
correct:						the correctness of the response (1 = correct; 0 = incorrect)
latency: 						the response latency (in ms)
/counttrials:					counts all stim trials

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

display.refreshrate:			the vertical refresh rate of the current monitor 
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)
/stimpic_height:				default height (in screen height %)

/propcorrect_stim1:				proportion correct responses for stim duration 1 (here: 6ms)
(the same for all 15 stim durations)


EXPERIMENTAL SET-UP
(1) 15 stimulus presentation durations tested with 20 repetitions (default).
Deary et al (2004) used the following durations: 6, 12, 19, 25, 31, 37, 44, 50, 62, 75, 87, 100, 125, 150, 200 ms
on a monitor with a vertical refresh rate = 160Hz
!!! Most monitors have a vertical refresh rate of 60Hz and therefore it won't be possible
to present any stimuli at 6 or 12 ms. One these computers it takes about 17ms (minimum) to refresh the screen.
(set durations under section EDITABLE CODE -> Editable Values)
(2) The stimuli duration times are selected randomly without replacement (method of constant stimuli).
(3) The short arm is located on the left for 50% of the trials
(4) Practice block for 25 randomly durations (number of trials can be edited)

Trial Sequence:
(1) Cue ('+') for 500ms (editable)
(2) Interstimulus interval: Blank screen for 600ms (editable)
(3) Stimulus for variable duration
(4) Mask for 500ms (editable)
(5) Trial continues until response is made
(6) Intertrial interval (blank screen) for 500ms (editable)

STIMULI
Stimuli are provided by Millisecond Software. They can be replaced under
section EDITABLE CODE -> Editable stimuli.
The target stimulus was created in such a way, that the long arm is twice the length
of the short arm (which equals the length of the crossbar)

Note: The size of the target stimulus in this script is coded in terms of canvas screen %.
In order to achieve, a size that is roughly equal to the one used by Deary et al (2004),
edit parameters.skip_stimsizecalibration under section EDITABLE CODE -> Editable Values
(default: true -> stim size calibration routine is not run).

INSTRUCTIONS
Instructions are provided by Millisecond Software in the form of htm pages.
Instructions can be edited directly in file "IT_intro.htm"
or replaced entirely.

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_left:						scancode of the left response key
											Note: scancodes under Tools -> Keyboard Scancodes (default: 30)
/responsekeyleft_label:					label of the left response key (default: 'A')
/responsekey_right:						scancode of the right response key
											Note: scancodes under Tools -> Keyboard Scancodes (default: 38)

/trials_perduration:					 number of trials per stimulusduration (default: 20)
											!!!Note: if that number is changed, list.stimdurations/list.stimduration_condition
											(section Editable Lists) need to be changed accordingly

/nr_practicetrials:						number of practice trials in this script. 
											Note: the durations are selected at random.

/fontsize_cue:							default height (in screen height %) of the cue (default: 10%)
/stimpic_height:						default height (in screen height %) (default: 26%)
											Note: Deary et al (2004): long arm = 5cm (short arm and cross bar = 2.5cm)
											Note: absolute sizing requires calibration for the current monitor 
											which is run if parameters.skip_stimsizecalibration = false (see below)

/cueduration:							duration of cue in ms (default: 500)
/cue_ISI:								cue(offset)-stim(onset) Interstimulus Interval in ms (default: 600)
/maskduration:							duration of mask in ms (default: 500)
/iti:									inter trial interval in ms (measured from response to onset of cue) (default: 500ms)

/skip_stimsizecalibration:				false: the picture stimulus can be sized to 5cm (Deary et al, 2004) prior to start of experiment on current monitor
										true: the calibration routine is skipped (default)

/stimduration1-
/stimduration15:						stores the 15 stimulus presentation durations in ms
										Note: Deary et al (2004) used:  6, 12, 19, 25, 31, 37, 44, 50, 62, 75, 87, 100, 125, 150, 200 ms
										on a monitor with a vertical refresh rate = 160Hz
										!!! Most monitors have a vertical refresh rate of 60Hz and therefore it won't be possible
										to present any stimuli at 6 or 12 ms. One these computers it takes about 17ms
										to refresh the screen.


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