Return to the Extrinsic Affective Simon Task page

Script Author: Jan De Houwer
last updated: 06-20-2019 by K.Borchert ( for Millisecond Software LLC


This script implements the Extrinsic Affective Simon Task by:

De Houwer, J. (2003). The Extrinsic Affective Simon Task. Experimental Psychology, 50, 77-85.

Millisecond Software thanks Dr. De Houwer for sharing his script!

Participants are presented white, blue, and green words of either positive or negative valence.											  
Participants are asked to categorize the white words into good key ('P') or bad Key ('Q') categories 
based on their meaning while at the same time they are asked to 
categorize blue and green words into the same good key ('P') or bad Key ('Q') categories simply based on their 
arbitrary color (half the participants categorize blue words as good and green as bad).

The default data stored in the data files are:

(1) Raw data file: 'standardEAST_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; by default data is collected unless /recorddata = false is set for a particular trial/block) 
stimulusitem:					the presented stimuli in order of trial presentation
response:						the participant's response
correct:						the correctness of the response (1 = correct; 0 = incorrect)
latency: 						the response latency (in ms) from onset of words

(2) Summary data file: 'standardEAST_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:					overall proportion correct in test trials
/meanRT:						overal mean latency (in ms) of correct test trials


1 Practice block categorizing white stimuli only - 20 trials (10 positive; 10 negative => 2 repetitions of stims)
1 Practice block categorizing blue/green words - 20 trials (5 positive green, 5 positive blue, 5 negative green, 5 negative blue)

3 Testblocks: mixed white words and colored words - 30 trials each (5 positive white, 5 negative white, 5 positive green, 5 positive blue, 5 negative green, 5 negative blue)

General Trial Sequence:
-> Pretrialpause (1000ms)
-> * (for 21 vertical frames: on a 60Hz monitor ~357ms) 
-> WORD until response (either correct or incorrect): words selected in random order
-> Errorfeedback (400ms)
-> Posttrialpause (200ms)

Note: blue/green assignment to good key/bad key is counterbalanced by groupnumber.
odd groupnumbers: blue -> positive key; green -> negative key
even groupnumbers: blue -> negative key; green -> positive key

see section Editable Stimuli

see section Editable Instruction

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:

/pretrialpause:								pretrialpauses in ms (default: 1000ms)
/posttrialpause:  							posttrialpauses in ms (default: 200ms)

Copyright © Millisecond Software. All rights reserved.
Contact | Terms of Service | Privacy Statement | Security Statement | GDPR
Website Security Test