Stereotype Activation Task

Technical Manual

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond

Created: January 06, 2016

Last Modified: January 16, 2023 by K. Borchert (katjab@millisecond.com), Millisecond

Script Copyright © Millisecond Software, LLC

Background

This script implements a variant of the Stereotype Activation Paradigm that measures stereotype activation/inhibition using reaction times to words (either control words or stereotype-relevant words) that follow the presentation of stereotype relevant imagery.

The procedure is closely related to a basic priming paradigm. In general, priming procedures are simple response-timed binary categorization tasks of items from two target categories (e.g. positive vs. negative adjectives). Priming Procedures are based on the assumption that people respond faster if the target category was already 'mentally activated' by briefly presenting items (called 'primes') that are closely connected in one's mind. Thus, a person should be faster to quickly categorize the target word 'good' as 'positive' after the brief presentation of the prime word 'ice-cream' than after the brief presentation of the prime word 'famine'.

In this script, the basic priming procedure is 'spread out' across two seemingly unrelated tasks. Task 1 presents the primes as images; Task 2 (a lexical decision task) presents the target words.

The implemented procedure is based on:

Moskowitz, G.B. & Li, P.(2011). Egalitarian goals trigger stereotype inhibition: A proactive form of stereotype control. Journal of Experimental Social Psychology, 47, 103–116.

Millisecond thanks Dr. Gordon Moskowitz and Joe Vitriol for their collaboration on this script!

Duration

12 minutes

Description

Participants work on 2 tasks that immediately follow one another: Trial1 (Task1) -> Trial2 (Task2) -> Trial3 (Task1) -> Trial4 (Task2) -> etc.

(1) Priming Task: participants see (a) an image of a black or white, male face (the target primes) OR an object (control primes) either above or below the fixation cross and (b) opposite to the prime (either below of above the fixation cross), a pair of letter strings (either words or nonWords) that are either the same (e.g. 'matter' 'matter') or different (e.g. 'across' 'policy'). The task is to decide as fast as possible whether the letter strings are the 'same' or 'different' while trying to ignore the distracting image (cover story).

(2) Lexical Decision Task: after the priming task, participants view a string of letters (the target) and have to decide whether the letters form a word or not.

For the critical trials in this task, participants see Black and White male faces as primes that are paired with a pair of identical nonWords in phase1. For task2, the Black and White primes (from task 1) each are followed by 8 stereotypic and 8 ctrl words.

Procedure

Practice: 16 trials total
- 8 trials with white faces:
4 with words in phase 2 (phase1: 1 with same words, 1 with different words, 1 with same nonWords, 1 with different nonWords)
4 with nonWords (phase1: 1 with same words, 1 with different words, 1 with same nonWords, 1 with different nonWords)
- 8 trials with objects:
4 with words in phase 2 (phase1: 1 with same words, 1 with different words, 1 with same nonWords, 1 with different nonWords)
4 with nonWords (phase1: 1 with same words, 1 with different words, 1 with same nonWords, 1 with different nonWords)

Error feedback during practice: red X presented for 500ms


Test: 2 test blocks: each run 56 trials -> 112 trials total
- each block runs:
• 16 critical trials:
4 trials – Black faces paired with identical non-words in phase 1 and stereotypic words in phase 2
4 trials -- White faces paired with identical non-words in phase 1 and stereotypic words in phase 2
4 trials – Black faces paired with identical non-words in phase 1 and control words in phase 2
4 trials -- White faces paired with identical non-words in phase 1 and control words in phase 2

•40 filler trials with 28 non-words and 12 words in phase 2 (since the critical trials above had 16 words)
12 white faces paired with non-words in phase 2 (4 same word, 4 different word, 4 different non-word in phase 1)
12 objects paired with filler words (4 same word, 4 different word, 4 different non-word in phase 1)
16 objects paired with non-words (4 same word, 6 different word, 6 different non-word in phase 1)

- the order of the trials is randomized
- all words/nonWords used in phase 2 are run twice

Trial Sequence:
Phase 1: FixationCross (2000ms) -> Image + Word Pair (presented for max.5000ms, above and below fixation cross) -> Response (Response Window: 1000ms, same as primeDuration) -> ITI: 400ms
Phase 2: Target Word/NonWord (stay on until Response or for max. 1500ms)

by default, the vertical position of the primes are selected randomly with replacement for each trial.


Response Button Assignment:
same (Phase1) + word (Phase2): same response key
different (Phase1) + nonWord (Phase2): same response key

The assignment of the two response buttons (default: Q (left), P (right) -> can be edited under section Editable Parameters)
is counterbalanced across groupnumbers.
odd groupnumbers: same/word -> Q; different/nonWord -> P
even groupnumbers: same/word -> P; different/nonWord -> Q

Stimuli

face stimuli: script uses placeholders as of now - pictures of black and white male faces can be downloaded from
from the Chicago Face Database: https://faculty.chicagobooth.edu/bernd.wittenbrink/cfd/index.html
Go to section 'Editable Stimuli' and replace the file names for the face primes.

object stimuli as well as word/nonWord stimuli: generously shared by Dr. Gordon Moskowitz

Instructions

provided by Millisecond - can be edited under section "Editable Stimuli"

Summary Data

File Name: stereotypeactivation_summary*.iqdat

Data Fields

NameDescription
inquisit.version Inquisit version number
computer.platform Device platform: win | mac |ios | android
startDate Date the session was run
startTime Time the session was run
subjectId Participant ID
groupId Group number
sessionId Session number
elapsedTime Session duration in ms
completed 0 = Test was not completed
1 = Test was completed
propCorrect Overall proportion correct (Lexical Decision Task)
meanRT Overall mean correct latency (in ms) (Lexical Decision Task)
sd Standarddeviation of correct latencies (in ms)
propCorrectBPrimeCtrl Proportion correct (Lexical Decision Task) for ctrl words following a Black prime face
propCorrectBPrimeStereotypic Proportion correct (Lexical Decision Task) for stereotypic words following a Black prime face
propCorrectWPrimeCtrl Proportion correct (Lexical Decision Task) for ctrl words following a White prime face
propCorrectWPrimeStereotypic Proportion correct (Lexical Decision Task) for stereotypic words following a White prime face
meanRTBPrimeCtrl Mean latency (in ms) of correct responses (Lexical Decision Task) for ctrl words following a Black prime face
meanRTBPrimeStereotypic Mean latency (in ms) of correct responses (Lexical Decision Task) for stereotypic words following a Black prime face
meanRTWPrimeCtrl Mean latency (in ms) of correct responses (Lexical Decision Task) for ctrl words following a White prime face
meanRTWPrimeStereotypic Mean latency (in ms) of correct responses (Lexical Decision Task) for stereotypic words following a White prime face
diffScoreCtrl Difference in mean latencies for ctrl targets after B primes and W primes (meanRTBPrimeCtrl - meanRTWPrimeCtrl)
diffScoreStereotypic Difference in mean latencies for stereotypic targets after B primes and W primes (meanRTBPrimeStereotypic - meanRTWPrimeStereotypic)
=> positive scores: Inhibition
=> negative scores: Activation/Facilitation
corrected mean latencies: removes all latencies that are 3 standard deviations (SD) or more away from the overall mean (meanRT)
corrMeanRTBPrimeCtrl Corrected mean latency (in ms) of correct responses (Lexical Decision Task) for ctrl words following a Black prime face
corrMeanRTBPrimeStereotypic Corrected mean latency (in ms) of correct responses (Lexical Decision Task) for stereotypic words following a Black prime face
corrMeanRtWPrimeCtrl Corrected mean latency (in ms) of correct responses (Lexical Decision Task) for ctrl words following a White prime face
corrMeanRtWPrimeStereotypic Corrected mean latency (in ms) of correct responses (Lexical Decision Task) for stereotypic words following a White prime face
corrDiffScoreCtrl Difference in mean latencies for ctrl targets after B primes and W primes (corrmeanRTBPrimeCtrl - corrmeanRTWPrimeCtrl)
corrDiffScoreStereotypic Difference in mean latencies for stereotypic targets after B primes and W primes (corrmeanRTBPrimeStereotypic - corrmeanRTWPrimeStereotypic)
=> positive scores: Inhibition
=> negative scores: Activation/Facilitation

Raw Data

File Name: stereotypeactivation_raw*.iqdat

Data Fields

NameDescription
build Inquisit version number
computer.platform Device platform: win | mac |ios | android
date Date the session was run
time Time the session was run
subject Participant ID
group Group number
session Session number
blockCode Name of the current block
blockNum Number of the current block
trialCode Name of the current trial
trialNum Number of the current trial
test 0 = practice phase; 1 = test phase
trialType 1 (critical) vs. 2 (filler)
phase 1 (priming task); 2 (lexical decision task)
prime 1 (Black faces); 2 (White faces); 3 (objects)
pairIdentity 1 (same/identical); 2 (different) (phase1)
wordType 1 = phase 1 WORDS; 2 = phase 1 NonWordS
target 1 (lexical decision task WORD); 2 (lexical decision task NON WORD)
valence 0 (filler words in phase2), 1 (ctrl target words in phase2); 2 (stereotypic target words in phase2)
primeStim The currently presented prime stimulus
letterString1 Phase 1 letter string 1
letterString2 Phase 1 letter string 2
targetStim The currently presented target stimulus
targetStimNr The itemnumber of the presented target stimulus
primeY Stores the y-coordinate (in %) of the current prime
letterStringY Stores the x-coordinate (in %) of the current letter string pair
letterString1 sits 2% above this location, letterString2 sits 2% below this location
response The participant's response (scancode of response button)
16 = Q
25 = P
57 = spacebar
0 = no response
responseCategory Stores the response classification
Phase 1: same or different
Phase 2: word or nonWord
correct The correctness of the response (1 = correct; 0 = incorrect)
latency The response latency (in ms)
phase1: measured from onset of letter strings
phase2: measured from onset of target words

Parameters

The procedure can be adjusted by setting the following parameters.

NameDescriptionDefault
leftKey The left keyboard scancode "Q"
rightKey The right keyboard scancode
Timing Parameters
"P"
fixationDuration The duration of the fixation cross 2000ms
maxPrimeDuration The max. duration of task 1 in ms 1000ms
iti The duration of the intertrial interval btw. task 1 and task 2 in ms 400ms
rwPhase2 The response window for phase 2 (lexical decision task) in ms
Sizing Parameters
1500ms
fixationSize The proportional screen size of the fixation cross 5%
pairFontSize The proportional screen size of the pair words in task 1 3%
targetFontSize The proportional screen size of the target string of letters in task 2 5%
primeSize The proportional screen size of the prime image 30%
topY The placement above the fixation cross in canvas screen percentages (50% = center) 30%
bottomY The placement below the fixation cross in canvas screen percentages (50% = center) 70%