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							SINGLE N-BACK TASK ADAPTIVE (1-KEY VERSION)
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software LLC
Date: October, 2011
last updated: 10-14-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Copyright © 10-14-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script implements an adaptive version of the non-adaptive single n-back task version 
as described in the following publication:

Jaeggi, Susanne M.; Studer-Luethi, Barbara; Buschkuehl, Martin; Su, Yi-Fen; Jonides, John; Perrig, Walter J. (2010). The 
relationship between n-back performance and matrix reasoning - implications for training and transfer. Intelligence, 38, 625–635.

Millisecond Software thanks Dr. Susanne Jaeggi for kindly providing original instruction materials, stimuli, as well as assistance!

This Inquisit script provides trials and instructions for adaptive single n-back tasks with random shapes (N = 1, N = 2, N = 3, N = 4),
inspired by the non-adaptive version with the same stimuli used  and kindly provided by Jaeggi et al (2010)- used in Experiment 1, as well 
as the general procedure described for adaptive n-back testing in Experiment 2. 
In this script, participants start out on level N = 1 and can move up indefinitely.


											  *Task*
In the 1-key single n-back task, participants are shown a sequence of stimuli (here: a sequence of yellow shapes 
on a black background) and asked to indicate whether the currently presented stimulus fulfills the following criteria:

In 1-key single n-back tasks, participants are shown a sequence of stimuli (here: a sequence of yellow shapes on a black background) and 
asked to indicate whether the currently presented stimulus fulfills the following criteria:

for N=1 trials:
- is the shape the same as the one that preceded it? If so (it's a target), and press "A". If not, don't respond.

for N=2 trials:
- is the shape the same as the one presented two trials before? If so (it's a target), and press "A". If not, don't respond.

for N=3 trials:
- is the shape the same as the one presented three trials before? If so (it's a target), and press "A". If not, don't respond.

etc.


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

(1) Raw data file: 'SingleTaskAdaptiveNBack_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 
values.N:						the type of N-back trial  
blockcode:						the name of the current block
values.TotalBlocks:				the total number of experimental blocks run
trialcode:						the name of the current trial
trialnum:						the current trial number
starttrialcounter:				keeps track of how many start trials have been run
stimulusitem:					the file of the stimulus shown during a trial
stimulusnumber:					the item number of the stimulus shown during a trial
values.currenttarget:			the item number of the current target
response:						the response of the participant
correct:						the correctness of the response
latency:						how fast a participant responded within the 3000ms timeframe, if at all
values.trial_Hit:				whether the response was a Hit (=1)
values.trial_FA:				whether the response was a False Alarm (=1)
values.trial_Miss:				whether the response was  Miss (=1)
values.trial_CR:				whether the response was a Correct Rejection ( = 1)
values.Hits:					the sum of Hits in a block
values.FalseA:					the sum of False Alarms in a block
values. Misses:					the sum of Misses in a block
values.CorrReject:				the sum of Correct Rejections in a block
values.TotalHits:				the sum of total hits across all experimental blocks
values.TotalFA:					the number of total false alarms across all experimental blocks
values.DV:						the proportion of (TotalHits - TotalFA)/number of experimental blocks

(2) Summary data file: 'SingleTaskAdaptiveNBack_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)
values.TotalHits:				the sum of total hits across all experimental blocks
values.TotalFA:					the number of total false alarms across all experimental blocks
values.DV:						the proportion of (TotalHits - TotalFA)/number of experimental blocks

EXPERIMENTAL SET-UP:
- After instructions, participants receive 10 trials of practice for levels N = 1 to N= 3, with possibility for more
- After practice, participants start on level N = 1, and depending on performance move up or stay on that level
- Adaptive testing is over after 15 blocks

BLOCK information:
- Each single n-task block consists of 20+ trials using 8 different shapes. 
=> + trials are the N trials that cannot display target shapes yet (=start trials). Their numbers vary depending on N. The data collected 
during these start trials are NOT included in performance counts for Correct Rejections/False Alarms.
=> Of the actual  20 experimental trials, 6 present a target and 14 do not. 
- The computer selects randomly 
a) whether it is a target trial or not and 
b) what shape to show if it is not a target trial
-adaptive blocks: 
(a) based on performance of participants either a higher, lower or the same level N is chosen for the following block (after 15 blocks the session is over)
(b) adaptive testing starts at level N = 1 in this script and can go up indefinitely
(c) participants receive performance feedback (% correct) after each block

TRIAL information:
- Each trial presents the shape for 500ms and waits another 2500ms before presenting the next shape in the sequence.
- Participants have the entire 3000ms to respond by pressing "A" if they detect a target.


INFORMATION FOR CODE-CHANGES (e.g. ADDITIONAL/DIFFERENT LEVELS OF N)

Instructions for changing code for additional Ns are provided with this script. Please check the following sections for the relevant info:
1. Custom Values
2. Instructions: (a) Instruction Slides -> Editable Instructions (b) Instruction Blocks -> section Instructions (block.Nbackinstruct_start)
3. Trials
4. Blocks: (a) Practice (b) Experimental


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:

/StartN = 1						the starting N
								!!!Note: if the starting N changes other changes may need to be made, e.g. instructions
/RepetitionPractice = 1			Number of repetitions per level N during practice (default for practice is 1)
/RepetitionTest = 3				Number of repetitions per level N during testing (default for test is 3)				
/debugmode = 0					debugmode = 1: targetalerts are shown on screen, debugmode = 0, no targetalerts are shown (default)
/stimulusPresentationtime:		the presentation time (in ms) of the stimuli (default: 500ms)
/SOA:							the stimulus onset asynchrony in ms (default: 3000ms)- also response window	

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