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									PARTIAL REPORT PROCEDURE
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 05-09-2014
last updated: 08-15-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Copyright © 08-15-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script runs a Partial Report Procedure (iconic memory) described by:

Lu, Neuse, Madigan, & Dosher (2005). Fast decay of iconic memory in observers with mild cognitive impairments. 
PNAS; 102; 1797-1802.

NOTE: this script includes a helper script to convert the percentage correct (for four-alternative
forced-identification) to d' scores as was done by Lu et al (2005). 
This helper script uses the conversion table by Hacker & Ratcliff (1979) and interpolates the 
final d' scores for the given percentages.

Hacker, M.J & Ratcliff, R. (1979). A revised table of d' for M-alternative forced choice. 
Perception & Psychophysics, 26, 168- 170.


											  *Task*
Participants view a circle made up of 8 letters (randomly sampled from: D, F, J, K) for a very brief
duration. Depending on condition, an arrow is presented before (=pre-cue), with (=simultaneous cue),
or after (=post-cue) the letter circle that points to one of the 8 letter positions. Participants
are asked to enter the letter into the keyboard*. Several Stimulus Onset Asynchronies (SOA)
are tested in the post-cue position.

* In contrast to Lu et al (2005) this script requires participants to enter the letter directly into the keyboard.
Alternatively, they could say the letter and experimenter types it in for them (as done in Lu et al).


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

(1) Raw data file: 'PartialReportProcedure_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
/condition:						1 = precue condition; 2 = simultan condition; 3 = postcue condition

trialcode, trialnum: 			the name and number of the currently recorded trial
								(Note: not all trials that are run might record data) 
/soa:							stores the current soa (stimulus onset asynchrony)
									precue: time between onset of cue and onset of letter circle
									postcue: time between onset of letter circle and onset of cue
/soa_index:						stores the index of the currently sampled SOA (the smaller the index the smaller the SOA)
/targetposition:				stores the position of the target (position 1-8; position 1 is 12 0'clock position; clockwise)
stimulusitem:					the presented stimuli in order of trial presentation (if any)
/letter1-
/letter8:						store the letters that are presented in each letter location
										(Note: position 1 is 12 0'clock position; clockwise)
/targetletter:					stores the target letter
response:						the participant's response (scancode of response key)
correct:						the correctness of the response
latency: 						the response latency (ms)


calculated at the end of all experimental blocks:
order reported: postcue (SOA1-SOA6), precue, simultan
/p:								p-values (proportions correct) for which a d'-value needs to be found (given values.m)
/d:								contains the calculated d'-value for the given values.p
/m:								number of forced choices available


(2) Summary data file: 'PartialReportProcedure_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)
/run_precue:					true (1) = script runs precue condition (default)
								false (0) = script does NOT run precue condition
/run_simultan:					true (1) = script runs simultan condition (default)
								false (0) = script does NOT run simultan condition
/run_postcue:					true (1) = script runs postcue condition (default)
								false (0) = script does NOT run postcue condition
/propcorrect_SOA1-
/propcorrect_SOA6:				proportion correct items recalled for postcue SOA1-SOA6 (across all postcue test blocks)
/propcorrect_postcue:			proportion correct items recalled in postcue condition across all SOAs (across all postcue test blocks)
/propcorrect_precue:			proportion correct items recalled in precue condition (across all precue test blocks)
/propcorrect_simultan:			proportion correct items recalled in simultan condition (across all simultan test blocks)

d-scores: store all the d' scores (calculated by included script: ProportionCorrect_to_dscore_conversion.iqx)
IF the given p-values are within range (0.01 < p < 0.99) otherwise d-value = "by hand"
/run_p_conversion:				true (1) = script automically converts the p-values (proportion corrects) into d'-scores using values (and interpolation) published by
								Hacker & Ratcliff (1979) (default)
										Note: border p-values (p-values < 0.01 and p-values > 0.99 have to be calculated manually)
								false (0) = script does not convert the p-values (proportion corrects) into d'-scores

d'-scores: store all the d' scores (calculated by included script: ProportionCorrect_to_dscore_conversion.iqx)
/dprime_SOA1 - dprime_SOA6
/dprime_precue-
/dprime_simultan
/m:								number of forced choices available (here: 4 as there are 4 letters to choose from: D, F, J, K)

!NOTE: correct latency data is stored in separate lists (see section LISTS) and can be used to calculate
mean latencies of correct responses in the different conditions.


EXPERIMENTAL SET-UP
3 conditions: pre-cue, simultan(eous) cue, post-cue

Pre-cue: arrow cue appears shortly before letter circle (only one SOA -> list.soa_precue)
		-> arrow and letter circle overlap
Simultan: arrow cue appears together with letter circle (SOA = 0)
Post-cue: arrow cue appears shortly after letter circle (6 SOA -> list.soa_postcue; randomly selected with replacement)
		-> no overlap of arrow and letter circle

8 target positions -> equally sampled across each condition (->list.targetposition)

By default, the script runs the pre-cue condition, the simultaneous cue condition and the post-cue condition in this order
(see section EXPERIMENT). Each of these conditions can be skipped by changing an editable value (e.g. /run_precue = false).
By default, each condition starts out with 50 practice trials that are followed by 96 test trials (number of trials
can be edited under Editable Values).

Note: participants are required to type in the letters directly into the keyboard (no voice recordings) 

STIMULI
Letter circles => letters are randomly sampled with replacement from list.consonant (D, F, J, K)
Size of letters, letter circle and arrows can be controlled via editable values: EDITABLE CODE -> Editable Values

INSTRUCTIONS
Instructions are not original. They are provided by Millisecond Software in the form of
image slides. To change the instructions, change the images (PowerPoint slides are provided in zip-file).
All instructions are posted 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:

/fontsize_target:						fontsize of the targets/letters in canvas height percentages (default: 10%)
/fontsize_fixation:						fontsize of the fixation mark in canvas height percentages (default: 3%)
/signalpicture_height:					size of arrow pictures in canvas heigh percentage (default: 10%)
/radiusscreenproportion:				the proportion of the letter circle radius relative to canvas height (default: 0.3)
											(Note: see Lu et al (2005), p.1798, for size information on their display)

/stimcircle_duration:					presentation duration of the targets/letters (default: 105ms)
/fixationduration:						presentation duration of the fixation stimulus (default: 400ms)
/iti:									intertrial interval between sequences (default: 500ms)

/nr_practicetrials:						number of practice trials in each condition (default: 50)
/nr_trials_postcue:						number of postcue trials during a test block (default: 96)
											Note: should be a multiple of 8 (targetpositions) and 6 (SOAs)
/nr_trials_precue:						number of precue trials during a test block (default: 96)
/nr_trials_simultan:					number of simultan trials during a test block (default: 96)

/run_precue:							true = script runs precue condition (default)
										false = script does NOT run precue condition
/run_simultan:							true = script runs simultan condition (default)
										false = script does NOT run simultan condition
/run_postcue:							true = script runs postcue condition (default)
										false = script does NOT run postcue condition

/run_p_conversion:						true = script automically converts the p-values into d'-scores using values (and interpolation) published by
										Hacker & Ratcliff (1979) (default)
											Note: border p-values (p-values < 0.01 and p-values > 0.99 have to be calculated manually)
										false = script does not convert the p-values into d-scores

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