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										TIMED CHASE TEST
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 10-23-2015
last updated: 08-15-2015 by K.Borchert for Millisecond Software LLC

Copyright © 08-15-2015 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script implements the Timed Chase Test (TCT) -a simple test of visuomotor processing speed- as described in:

Schroder, M.D, Snyder, P.J, Sielski, I. & Mayes, L. (2004). Impaired performance of children exposed in utero to cocaine
on a novel test of visuospatial working memory. Brain and Cognition, 55, 409–412.

Pietrzak, R. H., Cohen, H., & Snyder, P. J. (2007). Learning efficiency and error monitoring in normal aging: 
An investigation using a novel hidden maze learning test. Archives of Clinical Neuropsychology, 22, 235–245.

Mathewson, K.J., Dywan, J., Snyder, P.J., Tays, W.J., & Segalowitz, S.J.(2008). Aging and electrocortical response 
to error feedback during a spatial learning task. Psychophysiology, 45, 936–948.


											  *Task*
Participants are asked to capture a flag represented by a blue disc that jumps through the squares of a 
10x10 matrix. Once participants capture the flag, the flag jumps to a new location that is never more
than 2 squares away from the old location. Participants can only follow square by square in a horizontal
and vertical fashion; they cannot skip any square. If they make a mistake, they are directed to return 
to the last correct square.											  


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

(1) Raw data file: 'TimedChaseTest_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 
/phase:							1 = Untimed Chase; 2 = Timed Chase
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) 
/lastcorrectcell:				stores the number of the last correct cell
									Note: squares are labelled 1-100 from left to right
/selectnewflag:					1 = a new flag position needs to be found for next trial; 0 = flag stays put
/previousflagcell:				stores the number of the square the flag was previously on
/flagcell:						stores the number of the cell that contains the current flag
/absolutediff:					contains the absolute difference in box number between the previous and the current flag (for debug purposes)
response:						the participant's response
/selectedcell:					stores the number of the selected cell (the cell to which participant selected to move)
correct:						the correctness of the response (1 = correct; 0 = incorrect)
/ErrorType:						LE = Legal Error (one/first incorrect selection)
								PE = Perserverance Error (second incorrect selection in a row)
								RE = Rule break Error (third and more incorrect selections in a row)
latency: 						the response latency (in ms)

/count_moves:					counts the number of moves that participant makes (number of selections; selecting the disc at the beginning is not counted) in a block
/count_correctmoves:			counts the number of correct moves that a participant makes in a block
/count_correctionmoves:			counts the number of times participant correctly selects the last correct cell in a block
/count_errors:					sums up the number of errors made in a block
/ConsecutiveErrors:				contains the number of Consecutive Errors made (resets after a correct response is given)
/count_LE:						counts the number of times a Legal Error is made (one incorrect selection) per block
/count_PE:						counts the number of times a Perservative Error is made (two incorrect selections in a row) per block
/count_RE:						counts the number of Rule breaking Errors (three or more consecutive selections) per block


(2) Summary data file: 'TimedChaseTest_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)
/count_moves:					counts the number of moves that participant makes (number of selections; selecting the disc at the beginning is not counted) in the timed block
/count_correctmoves:			counts the number of correct moves that a participant makes in the timed block
/count_correctionmoves:			counts the number of times participant correctly selects the last correct cell in the timed block
/count_errors:					sums up the number of errors made in the timed block
/count_LE:						counts the number of times a Legal Error is made (one incorrect selection) in the timed block
/count_PE:						counts the number of times a Perservative Error is made (two incorrect selections in a row) in the timed block
/count_RE:						counts the number of Rule breaking Errors (three or more consecutive selections) in the timed block
/CMS:							calculates the number of correct moves made per second in timed chase block ~ a measure of low-demand visuomotor speed



EXPERIMENTAL SET-UP
2 Blocks:
1) Untimed Chase: Participants start the block by clicking on the blue disc that is presented in the top left square.
The disc then appears in a new location (never more than 2 squares/moves away). Locations are randomly determined.
Participants have to 'capture' the  disc by following square by square (on the shortest possible route towards the flag); 
only moves immediately up and down as  well as right and left are allowed. If participants choose a correct square, the square 
turns green (and a chirp is played) and participant can continue. If participants make a mistake, the square turns red 
(and a different sound is played) and participants need to  return to the last correct square. 
After 3 incorrect moves, the only square that can be selected is the last correct 
square which is indicated by a flashing"!". The block ends by clicking a button labeled "done" at the bottom.

2) Timed Chase: The timed blocks runs for a predetermined length of time (default: 30s). No 'done' button is 
provided. Otherwise, the same rules apply as for the untimed block.
The number of correct moves is counted.
	
STIMULI:
flag = blue disc
10x10 matrix, gray squares

INSTRUCTIONS
are not original. They are provided as simple htm documents and can be edited directly in the htm files.

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:

/duration_timedblock:			duration of the timed block in ms (default: 30000)
/showerrorreminder:				true = a verbal reminder to return to the last correct square is presented once participants has selected 3 incorrect squares
								false = no verbal reminder is presented
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