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							SPLIT VISUAL FIELD PARADIGM (SVFP)
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 07-17-2014
last updated: 06-02-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Copyright © 06-02-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script runs the Split Visual Field Paradigm as described by:

Patel UJ, & Hellige JB. (2007). Benefits of interhemispheric collaboration can be eliminated by mixing stimulus 
formats that involve different cortical access routes. Brain Cognition, 63, 145-58. Epub 2006 Dec 15.

											  *Task*
Participants are presented with 3 number stimuli on the screen: 2 numbers on the top of the screen - one 
in the upper left quadrant and one in the upper right quadrant- and one number either in the bottom left
or the bottom right quadrant. Participants have to press the  if the number on the bottom is
a match to one of the top displayed numbers.
Numbers can either be digits or dice dots. The two top stimuli are always of the same format.

Experiment 1 (parameters.version = 1):
* Random sampling of numbers (without replacement) from numbers 1-6
* Matches = same number

Experiment 2 (parameters.version = 2):
* Random sampling of numbers (without replacement) from numbers 1-6
with following restrictions: never show 1 and 2 together (numbergroup 1), never present 3 and 4 together (numbergroup2), never present 5 and 6 together (numbergroup3)
* Matches = number from the same numbergroup (NEVER the actual same number)



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

(1) Raw data file: 'SplitVisualField_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 
/version:						1 = Experiment1 set up (same numbers = the actual same numbers)
								2 = Experiment2 set up (same numbers = number from same category)
/mixedcondition:				"A": digits on top, dice Dot on bottom
								"B": dice Dot on top, digits on bottom (tested between participants)
/blockorder:						1 = Digits, Dots, Mixed
									2 = Mixed, Digits, Dots
									3 = Dots, Mixed, Digits
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) 

/practice:						0 = test trials; 1 = practice trials
/format:						'Digits', 'Dots', 'Mixed'
/match:							'Match' vs. 'NoMatch'
/side:							lower number is on 'Left' or 'Right'
/sidematch:						match is 'same' or 'across' or 'not applicable' (because there is no match)
/TopLeft:						the stimulus presented on the top left
/TopRight:						the stimulus presented on the top right
/Bottom:						the stimulus presented on the bottom
/bottomPosition: 				stores the x-coordinate of the bottom stim
response:						the participant's response
correct:						the correctness of the response
latency: 						the response latency

(2) Summary data file: 'SplitVisualField_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)
/version:						1 = Experiment1 set up (same numbers = the actual same numbers)
								2 = Experiment2 set up (same numbers = number from same category)

/mixedcondition:				"A": digits on top, dice Dot on bottom
								"B": dice Dot on top, digits on bottom

/propcorrect_Digits_NoMatch: 	prop correct for trials in which only digits without a match were presented
/meanerrorRT_Digits_NoMatch:	mean error latency for incorrect responses in trials in which only digits without a match were presented
/propcorrect_Dots_NoMatch: 		prop correct for trials in which only dice Dots without a match were presented
/meanerrorRT_Dots_NoMatch:		mean error latency for incorrect responses in trials in which only dice Dots without a match were presented
/propcorrect_Mixed_NoMatch: 	prop correct for trials in which mixed formats without a match were presented
/meanerrorRT_Mixed :			mean error latency for incorrect responses in trials in which mixed formats without a match were presented

/propcorrect_Digits_Match_Same:		prop correct for only digits trials with a same side match
/meanRT_Digits_Match_Same:			mean correct latency for only digits trials with a same side match
/propcorrect_Digits_Match_Across:	prop correct for only digits trials with a cross side match
/meanRT_Digits_Match_Across:		mean correct latency for only digits trials with a cross side match
/propcorrect_Dots_Match_Same:		prop correct for only dice Dots trials with a same side match
/meanRT_Dots_Match_Same:			mean correct latency for only dice Dots trials with a same side match
/propcorrect_Dots_Match_Across:		prop correct for only dice Dots trials with a cross side match
/meanRT_Dots_Match_Across:			mean correct latency for only dice Dots trials with a cross side match
/propcorrect_Mixed_Match_Same:		prop correct for mixed format trials with a same side match
/meanRT_Mixed_Match_Same:			mean correct latency for mixed format trials with a same side match
/propcorrect_Mixed_Match_Across:	prop correct for mixed format trials with a cross side match
/meanRT_Mixed_Match_Across:			mean correct latency for mixed format trials with a cross side match

EXPERIMENTAL SET-UP
3 format conditions: only digits (Digits), only dice Dots (Dots) or mixed (Mixed) formats
are tested within participants in a blocked design.
Block order is tested in a Latin Square design between participants.
Mixed format has 2 variations (A or B): 
	A: top numbers are digits and bottom number is a dice Dot 
	B: top numbers are dice Dots and bottom number is a digit

- Assignment is done by groupnumber (1-6)
(see section EXPERIMENT for details on how participants are assigned to each condition)

Test Blocks:
- 64 trials per format block; 4 blocks of the same format run sequentially => 256 trials per format
- 32 Match trials; 32 NoMatch trials
- 16 of the 32 (Match/NoMatch) trials present the digit on the left (right)
- 8 of the 16 Match trials with digits on the left (right) present the matching digit on the SAME monitor side;
the other 8 present the matching digit on the opposite (ACROSS) side
(=> 16 Same Match trials and 16 Across Match trials per block)

Note: version 2: numbergroups are determined randomly with each numbergroup having the same probability of being sampled, 
the actual frequency of each of the 3 numbergroups might, however, differ.

Practice Blocks:
- 1 practice block before each format test condition
- 24 trials
- error feedback: present (1) the previous number set-up and (2) correct response (3) errorbeep

Trial Sequence:
- Fixation Cross: 
	* present fixation cross for 2100ms (default) before onset of number array, 
	* present short beep 1050ms (default) before onset of number array
- Number Array (depending on format): numbers are presented for 195ms (default);
	participants have 2100ms to respond (by default, a new trial sequence starts either
	after a response or after 2100ms whichever comes first)
- Practice only: Error Feedback trial

STIMULI
Digits: 1-6
Dice Dots: 1-6, provided by Millisecond Software (can be replaced under Editable Stimuli -> item.diceDots)

USER INTERFACE
Display of Stimuli (Size and Position) on-screen can be controlled via Editable Values. 

INSTRUCTIONS
provided by Millisecond Software, can be replaced under Editable Instructions.
!!!Note: the default instructions are for Experiment 1 (version 1). If version 2 is run, the instructions
need to be updated accordingly.

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:

/version:								1 = Experiment1 set up (same numbers = the actual same numbers) (default)
										2 = Experiment2 set up (same numbers = number from same category)
										!!!NOTE: Instructions are provided for version 1; if version 2 is run
										the instructions need to be updated accordingly
										
/responsekey:							scancode of the response key
											Note: scancodes under Tools -> Keyboard Scancodes (default: 57)
/responsekey_label:						label of the response key (default: )


Fine-tuning of UI:						see Patel & Hellige (2007, p. 149) for specifics
/fontsize_target:						fontsize of the targets in screen height percentages (default: 10%)
/pictureheight:							height of dice Dot pictures in screen height percentages (default: 10%)
/fontsize:						fontsize of the fixation mark in screen height percentages (default: 5%)

/upperleft_x-
/upperleft_y:							x,y coordinates (in % of screen height/width) for stimuli presented on the upper left side
/lowerleft_x-
/lowerleft_y:							x,y coordinates (in % of screen height/width) for stimuli presented on the lower left side
/upperright_x-
/upperright_y:							x,y coordinates (in % of screen height/width) for stimuli presented on the upper right side
/lowerright_x-
/lowerright_y:							x,y coordinates (in % of screen height/width) for stimuli presented on the lower right side

Durations:
/responsewindow:						time (in ms) participants have to respond to stim array presentation (default: 2100ms)
/fixationduration:						time (in ms) that fixation is presented before the beep (default: 1050ms -> 2100ms presentation of fixation cross before stim array is presented)
/stimpresentation:						time (in ms) the stim array is presented (default: 195ms)

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