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										Number Bisection Task
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 09-06-2018
last updated: 09-12-2018 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Script Copyright © 09-12-2018 Millisecond Software


BACKGROUND INFO 

											*Purpose*
This script implements the Number Bisection Task based on:

Nuerk, H., Geppert, B., van Herten, M., & Willmes, K. (2002). On the impact of
different number representations in the number bisection task. Cortex, 1,
691–715.

											  *Task*
Participants view a series of triplets of numbers (e.g. 5-7-9), each presented for max.3s, 
and have to decide whether the center number is the arithmetic mean of the flanking numbers.


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

(1) Raw data file: 'numberbisectiontask_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 but they will still be reflected by trialnum; 
									by default data is collected unless /recorddata = false is set for a particular trial/block) 

/blockcount:					block count (for test blocks only)									
/trialcount:					number of test trials run in the current block
/bisectionality:				1 = bisectional; 2 = non-bisectional
/multiplicativity:				for bisectional problems only: 
									1 = multiplication triplets from a number sequence (e.g. 2-4-6, 14-21-28); 
									2 = otherwise (e.g. 3-8-13)
/bisectionTaskRange:			for bisectional problems only: 
									1 = difference btw. the target numbers ('outer numbers') is btw. 2-8 (e.g. 4-7-10 => 10-4 = 6)
									2 = difference btw. the target numbers ('outer' numbers) is btw. 12-18 (e.g. 4-12-20 => 20-4 = 16)
/bisectionPossibility:			for non-bisectional problems only:
									1 = the actual arithmetic mean of the target numbers (=mean of first and third number) is an integer (e.g. 4-8-10; (4+10)/2 = 7)
									2 = otherwise (e.g. 4-7-9 => (4+9)/2 = 6.5)
/distance:						for non-bisectional problems only:
									1 = the absolute difference btw. the actual mean of the target numbers (=mean of first and third number) 
									and the provided arithmetic mean (= the second number) is 0.5-1.5 (e.g. 3-6-7; (3+7)/2=5; 6-5 = 1)
									2 = the absolute difference btw. the actual mean of the target numbers (=mean of first and third number) 
									and the provided arithmetic mean (= the second number) is 2-8	(e.g. 12-18-20; (12+20)/2=16; 18-16 = 2)								
																		
stimulusitem:					the presented number triplet
response:						the participant's response: scancode of response button (0 = no response)
/resp:							"yes" vs. "no" vs " " (empty = no response)
correct:						accuracy of response: 1 = correct response; 0 = otherwise
latency: 						the response latency (in ms); measured from:


(2) Summary data file: 'numberbisectiontask_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)


Note: mean response times are based on correct responses with latencies >= 200

/propCorrect_bisectional_multi_small:		proportion correct responses for bisectional, 'multiplication-triplets' problems with a small task range
/meanRT_bisectional_multi_small:			mean response time (in ms) of correct responses for bisectional, 'multiplication-triplets' problems with a small task range
/propCorrect_bisectional_multi_wide:		proportion correct responses for bisectional, 'multiplication-triplets' problems with a wide task range
/meanRT_bisectional_multi_wide:				mean response time (in ms) of correct responses for bisectional, 'multiplication-triplets' problems with a wide task range
/propCorrect_bisectional_nonmulti_small:	proportion correct responses for bisectional, 'non-multiplication-triplets' problems with a small task range
/meanRT_bisectional_nonmulti_small:			mean response time (in ms) of correct responses for bisectional, 'non-multiplication-triplets' problems with a small task range
/propCorrect_bisectional_nonmulti_wide:		proportion correct responses for bisectional, 'nonmultiplication-triplets' problems with a wide task range
/meanRT_bisectional_nonmulti_wide:			mean response time (in ms) of correct responses for bisectional, 'non-multiplication-triplets' problems with a wide task range

/propCorrect_nonbisectional_possible_near:	proportion correct responses for nonbisectional, 'possible mean' problems with a near distance of suggested mean to actual mean
/meanRT_nonbisectional_possible_near:		mean response time (in ms) of correct responses for nonbisectional, 'possible mean' problems with a near distance of suggested mean to actual mean
/propCorrect_nonbisectional_possible_far:	proportion correct responses for nonbisectional, 'possible mean' problems with a far distance of suggested mean to actual mean
/meanRT_nonbisectional_possible_far:		mean response time (in ms) of correct responses for nonbisectional, 'possible mean' problems with a far distance of suggested mean to actual mean
/propCorrect_nonbisectional_impossible_near:	proportion correct responses for nonbisectional, 'impossible mean' problems with a near distance of suggested mean to actual mean
/meanRT_nonbisectional_impossible_near:		mean response time (in ms) of correct responses for nonbisectional, 'impossible mean' problems with a near distance of suggested mean to actual mean
/propCorrect_nonbisectional_impossible_far:	proportion correct responses for nonbisectional, 'impossible mean' problems with a far distance of suggested mean to actual mean
/meanRT_nonbisectional_impossible_far:		mean response time (in ms) of correct responses for nonbisectional, 'impossible mean' problems with a far distance of suggested mean to actual mean


* separate data files: to change to one data file for all participants (on Inquisit Lab only), go to section
"DATA" and follow further instructions


EXPERIMENTAL SET-UP

1. Practice: 32 trials
* 16 bisectional triplets (range: 2-18); 16 non-bisectional triplets (range: 2-18)
* triplets presented randomly
* performance feedback provided for 1000s

Trial Sequence:
* presentation of triplets: max. 3000ms (terminates with response)
* feedback for 1000ms
* interstimulus interval of 1.5s in between triplets (presents a fixation cross)
(Note: the SOA during practice is variable due to the feedback presentation)


2. Test:
* 5 Blocks of 72 trials each = 360 trials total
* each blocks runs 9 trials of each of the 8 possible trials
(trial.bisectional_multi_small...trial.nonbisectional_impossible_far)
* order of trials is selected randomly (as is the selection of the triplets)
* no feedback

Trial Sequence:
* A new triplet appears with a stimulus onset asynchrony (SOA) of 4.5s
* each triplet is presented for max. 3s (= response window)
* interstimulus interval of min. 1.5s in between triplets (presents a fixation cross)

STIMULI
Test Triplets: This script uses the 360 triplets provided by Nuerk et al (2002)
the size can be fine-tuned under section Editable Parameters

Practice Triplets: the practice triplets are novel triplets generated by Millisecond Software (none of the practice
triplets are used during the test)
- half of the practice triplets (16) are bisectional triplets (range: 2, 4, 6, 8, 10, 12, 18; two of each)
- half of the practice triplets (16) are non-bisectional triplets (range: 2, 4, 6, 8, 10, 12, 18; two of each)

all triplets can be edited under section Editable Stimuli

INSTRUCTIONS
provided by Millisecond Software - can be edited under section Editable Instructions

DURATION
The default set-up runs appr. 45 minutes
Practice block: 32 trials => appr. 3 minutes
Test block: 72 trials => appr. 7 minutes 

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:
/numberOfPracticeTrials:			the number of practice trials to run (default: 32)
										Notes: 
											(1) the number should be divisible by 2
											(2) for numbers > 32, triplets will be repeated
											(3) for numbers < 32, the randomly selected ranges of the triplets (range = difference btw. outer numbers)
											might not be balanced across bisectionable and non-bisectionable triplets
											To get a balanced number of ranges, consider reducing the appropriate item lists under
											section Editable Stimuli (item.practice_bisect; item.practice_nonbisect)
										
/numberOfTestBlocks:				the number of test blocks to run (default: 5); each testblocks runs 72 trials
										Notes:
											(1) for numbers > 5, triplets will be repeated
											(2) for numbers < 5, randomly chosen triplets will not be the same across participants.
											To get the same triplets for all participants, consider reducing the appropriate item lists under
											section Editable Stimuli.

/stimPresentationTime:				maximum stimulus presentation time in ms (default: 3000ms) => response window
/ISI:								minimum interstimulus interval in ms (default: 1500ms)
									Note: a new triplet appears every 4.5s (SOA= 3000ms + 1500ms)
									
/minLatency:						the minimum response time that is considered a valid response time (default: 200ms)

/stimSize:							the proportional size of the triplets (relative to canvas) (default: 7%)
/fixationSize:						the proportional size of the fixation cross (relative to canvas) (default: 7%)

/responsekey_yes:					scancode of the 'yes' response button (here: 18)
										see Tools -> Keyboard Scancodes
/responsekey_yes_label:				the label that belongs to the 'yes' scancode (here: E)
/responsekey_no:					scancode of the 'no' response button (here: 23)
/responsekey_no_label:				the label that belongs to the 'no' scancode (here: I)

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