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							 RAPID VISUAL INFORMATION PROCESSING
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
last updated: 03-18-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Copyright © 03-18-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script implements the Rapid Visual Information Processing Task described in:

Wesnes, K. & Wartburton, D.M (1984), Effects of scopolamine and nicotine on human rapid information processing performance. 
Psychopharmacology, 82, 147-150.

											  *Task*
A participant is presented with a series of digits (1-9) on a computer screen. The presentation time is 100 digits/min (or 1digit/600ms)
The participant's task is to press a response key (here: Spacebar) as soon as she detects a series of three consecutive odd 
or three consecutive even digits.


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

(1) Raw data file: 'RVIP.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; by default data is collected unless /recorddata = false is set for a particular trial/block) 
/values.focusdigit1:			the three digits that need to be checked to see if they are all odd or all even														
/values.focusdigit2 :
/values.focusdigit3 :
/digit:							the digit presented in the current trial
/btwtargets_counter:			counts the number of digits between target trials
/target:						0 = no target presented; 1 = target presented (the third digit in a row of either all odd or all even digits)
targetstarttime:				the script elapsed time (in ms) the last target was presented 
/starttrialtime :				the script elapsed time the current trial started (in ms)
/target_responsewindow:			the time window during which a target is active (here: up until 1500ms after onset of a target, consistent with Wesnes & Wartburton (1984))
/target_responseendtime:		values.starttrial of a target-trial + values.interval (in ms)
/responsetime:					the script elapsed time when a response is made (in ms)
/RT_hit:						the response latency (in ms) for the current Hit; measured as difference between responsetime-targetstarttime
latency: 						the trial latency (in ms) (for the current trial)
targetactive:					0 = target not active; 1 = target still active
response:						the participant's response (e.g. scancode of response key)
correct:						the correctness of the response (1 = correct; 0 = incorrect)
/sumtargets:					counts how many targets have been presented
/Hit :							the correct response (= pressing the Spacebar) to an active target
/FA :							incorrectly pressing the Spacebar if there is no target active (=False Alarm)
/SumHit:						counts the number of Hits
/SumFA :						counts the number of False Alarms

(2) Summary data file: 'RVIP_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)
/propcorrect:					proportion correct target detection (test)
/sumtargets:					counts how many targets have been presented (test)
/SumHit:						counts the number of Hits (test)
/SumFA :						counts the number of False Alarms (test)
/meanRT_hit:					determines the mean hit RT (in ms) - measured from onset of last target digit (test only)
/Std_hit:						determines standard deviation of hit RTs (test only)
/medianRT_hit:					determines the median hit RT (in ms) - measured from onset of last target digit (test only)



EXPERIMENTAL SET-UP
This script provides a testing sequence of 1200 digits with 97 target sequences as well as a practice sequence of 20 digits with
2 target sequences. The target sequences (testing) are separated by a minimum of 5 and a maximum of 33 digits (Mean = 9.3).
Feedback is provided at the end of each block - to remove feedback go to section BLOCKS and follow further instructions.

The response is scored as a Hit if the participant reacts within 1500ms (target response window described in article, can be changed by 
experimenter in this script) of  onset of the last digit of a target sequence. Any response that occurs later is scored as a False Alarm. 

STIMULI
see section Editable Lists for the currently available stim sequences

INSTRUCTIONS
to edit instructions, go to section 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:

target_responsewindow:							the time window (in ms) during which a target is active (here: up until 1500ms after onset of a target, consistent with Wesnes & Wartburton (1984))
presentationtime:								how long (in ms) a stimulus is presented before the next one replaces it (= frequency of showing a stimulus) (here: 100 digits/ 1min => 600ms per stimulus, consistent with Wesnes & Wartburton (1984).)
digitheight:									controls the size of the digits (percentage of screen height, default: 5%)

sequencelength_practice:						the length of the practice sequence
													Note: if the number is changed here, list.digitsequence_practice might also need to be updated
sequencelength_test:							the length of the test sequence
													Note: if the number is changed here, list.digitsequence might also need to be updated

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