The Emotional Stroop Task: Assessing Cognitive Performance under Exposure to Emotional Content

Summary

The emotional Stroop effect (ESE) is the result of longer naming latencies to ink colors of emotion words than those of neutral words. This report refers to potential sources of confounding and includes a modal experiment that provides the means to control for them.

Abstract

The emotional Stroop effect (ESE) is the result of longer naming latencies to ink colors of emotion words than to ink colors of neutral words. The difference shows that people are affected by the emotional content conveyed by the carrier words even though they are irrelevant to the color-naming task at hand. The ESE has been widely deployed with patient populations, as well as with non-selected populations, because the emotion words can be selected to match the tested pathology. The ESE is a powerful tool, yet it is vulnerable to various threats to its validity. This report refers to potential sources of confounding and includes a modal experiment that provides the means to control for them. The most prevalent threat to the validity of existing ESE studies is sustained effects and habituation wrought about by repeated exposure to emotion stimuli. Consequently, the order of exposure to emotion and neutral stimuli is of utmost importance. We show that in the standard design, only one specific order produces the ESE.

Introduction

Modern life is replete with emotion and stress. Who has avoided the emergency room or (witnessing) a traffic accident? In order to perform efficiently under such stressful situations, it is important to preserve one's composure by focusing on the relevant stimuli. However, research has shown that the emotional valence of the stimulus can affect attention, in particular modulate the speed of processing. In the laboratory, one of the most popular paradigms to study the effect of negative stimuli on performance is the emotional Stroop task. The typical finding is that it takes people longer to name the ink color of emotion words than that of neutral words, the Emotional ....

Protocol

The protocol follows the guidelines of Tel-Aviv University Helsinki human research ethics committee.

1. Word Selection and Matching

1. Create lists of words for each word category of interest. For example, make lists of generally emotional words (e.g., HATE, POX), concern relevance words (e.g., RAPE, VICTIM), and neutral words that are preferably orthographic neighbors²¹ of the emotional/concern relevant words (e.g., GATE, BOX). Create lists with as many words as possible as not all of these words will be used; a smaller subset of matched words will later be selected. 
   1. When deemed....

Results

When blocks follow the neutral-emotion-neutral sequence (e.g., ³), a large ESE of 34 msec is observed via slower responses in the emotion block (mean of 791 msec) than in the first neutral block (mean of 757 msec; see Figure 2). The same group of participants was also fairly sluggish to name the ink color in the second set of (other) neutral words (mean of 778 msec). The 21 msec difference in performance between the two blocks with neutral items docume.......

Discussion

The ESE comprises a very simple task: The participant names the ink color of singly presented words. This simple task yields results of both pragmatic and theoretical consequence. The ESE documents the fact that people are sensitive to the emotional valence entailed in stimuli although this feature is completely irrelevant to the task at hand.

The ESE has evolved into an immensely popular method for probing emotion and anxiety with both patient and non-patient populations^{1, 74<.......}

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
DirectRT software	Empirisoft	http://www.empirisoft.com/directrt.aspx	Software allows easy programing of a custom experiment in a spreadsheet application (e.g., Excel)
Personal computer	Any	https://www.office.com/	At least 256 mb of memory, a graphics card with at least 16 mb of video memory and a processor speed of at least 500 mhz.
A spreadsheet application (e.g., Excel)	Microsoft	Any version	A spreadsheet application capable of editing CSV files
SPSS/STATISTICA software	IBM/Statsoft	http://www-01.ibm.com/software/analytics/spss/  http://www.statsoft.com/	Statistical software