Script Author: Sean Draine (seandr@millisecond.com)
Last Modified: January 25, 2025 by K. Borchert (katjab@millisecond.com), Millisecond
Script Copyright © Millisecond Software, LLC
The Implicit Association Task (Greenwald, McGhee, & Schwartz, 1998) is a widely-used cognitive-behavioral paradigm that measures the strength of automatic (implicit) associations between concepts in people’s minds relying on latency measures in a simple sorting task.
This IAT measures the strength of automatic (implicit) associations between the target categories (Death/Life) and attribute categories (Me vs. Not Me). The main Dependent Variable is the D-Score ('Difference Score').
D-scores obtained with this script: Positive d-scores: support a stronger association between 'Death-Me' and 'Life-No Me' than for the opposite pairings Negative d-scores: support a stronger association between 'Life-Me' and 'Death-Not Me' than for the opposite pairings
Greenwald, A. G., McGhee, D. E., & Schwartz, J. K. L. (1998). Measuring individual differences in implicit cognition: The Implicit Association Test. Journal of Personality and Social Psychology, 74, 1464-1480.
Greenwald, A. G., Nosek, B. A., & Banaji, M. R. (2003). Understanding and Using the Implicit Association Test: I. An Improved Scoring Algorithm. Journal of Personality and Social Psychology, 85, 197-216.
5.5 minutes
Participants are asked to categorize attributes (e.g. "joyful"; "tragic") and target items (e.g "daisy" vs. "wasp") into predetermined categories via keystroke presses. The basic task is to press a left key (E) if an item (e.g. "joyful") belongs to the category presented on the left (e.g. "Good") and to press the right key (I) if the word (e.g. "tragic") belongs to the category ("Bad") presented on the right. For practice, participants sort items into the target categories "Flowers vs. Insects" and the attribute categories "Good vs. Bad". For the test, participants are asked to sort categories into the paired/combined categories (e.g. "Flower OR Good" on the left vs. "Insect OR Bad" on the right). Pairings are reversed for a second test (e.g. "Insects OR Good" on the left vs. "Flowers OR Bad" on the right). Block order is counterbalanced by groupnumber.
Hypothesis-consistent pairings vs. hypothesis-inconsistent pairings; tested within-subjects in a blocked format
=> order is counterbalanced by groupnumber assignment
odd groupnumbers run: consistent - inconconsistent pairings
even groupnumbers run: inconsistent - consistent pairings
Block Sequence:
1. Target Category sorting training
2. Attribute sorting training
3. 1. Test Block of hypothesis-consistent* pairings with 20 trials (half the participant start with inconsistent pairings)
4. 2. Test Block of hypothesis-consistent pairings with 40 trials
5. Target Category sorting training with targets switching sides
6. 1. Test Block of hypothesis-inconsistent pairings with 20 trials
7. 2. Test Block of hypothesis-inconsistent pairings with 40 trials
In all Test Blocks:
• attributes and targets alternate
• attributes as well as targets are randomly selected without replacement
Trial Sequence:
Target -> until correct response -> ISI: 250ms (default)-> Target....
- iat dependent code can be found in script file "xxxiat_stimuli_inc.iqjs" (xxx=specific iat)
- generic instructions can be found in in script file "iat_instructions_inc.iqjs" (language dependent)
In general:
• start instruction page is provided as an html page. It automatically adapts to different images and category labels UNLESS
the number of attributes and/or targets have been changed. In this case, changes have to be
made to file "intro_iat.htm", so that the correct number of items are presented in the overview table.
Example: instead of 8 words for target A, only 5 should be presented:
in file "intro_iat.htm":
change:
File Name: iat_summary*.iqdat
| Name | Description |
|---|---|
| inquisit.version | Inquisit version number |
| computer.platform | Device platform: win | mac |ios | android |
| computer.touch | 0 = device has no touchscreen capabilities; 1 = device has touchscreen capabilities |
| computer.hasKeyboard | 0 = no external keyboard detected; 1 = external keyboard detected |
| 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 |
| conditionOrder | C-ic: consistent -> inconsistent ic-c: inconsistent -> consistent |
| da | D-score of the first short blocks |
| db | D-score of the second long blocks |
| d | Overall d-score (non-weighted mean of the 2 d-scores); main DV Suggested Interpretation D-score <= -0.65 => "a strong" preference for hypothesis-NONconforming pairings D-score < -0.35 => "a moderate" preference for hypothesis-NONconforming pairings D-score < -0.15 => "a slight" preference for hypothesis-NONforming pairings -0.15 <= D-score <= 0.15 "little to no" preference D-score > 0.15 => "a slight" preference for hypothesis-conforming pairings D-score > 0.35 => "a moderate" preference for hypothesis-conforming pairings D-score >= 0.65 => "a strong" preference for hypothesis-conforming pairings |
| percentCorrect | The overall percent correct score of initial responses in test trials of D-score qualifying latencies |
| propRT300 | The proportion of response latencies < 300ms |
| excludeCriteriaMet | 1 = yes, exclusion supported per Greenwald et al (2003, p.214, Table 4) More than 10% of all response latencies are faster than 300ms 0 = otherwise |
File Name: iat_raw*.iqdat
| Name | Description |
|---|---|
| build | Inquisit version number |
| computer.platform | Device platform: win | mac |ios | android |
| computer.touch | 0 = device has no touchscreen capabilities; 1 = device has touchscreen capabilities |
| computer.hasKeyboard | 0 = no external keyboard detected; 1 = external keyboard detected |
| date | Date the session was run |
| time | Time the session was run |
| subject | Participant ID |
| group | Group number |
| session | Session number |
| blockcode | The name the current block (built-in Inquisit variable) |
| blocknum | The number of the current block (built-in Inquisit variable) |
| trialcode | The name of the currently recorded trial (built-in Inquisit variable) |
| trialnum | The number of the currently recorded trial (built-in Inquisit variable) trialnum is a built-in Inquisit variable; it counts all trials run even those that do not store data to the data file. |
| conditionOrder | C-ic: consistent -> inconsistent ic-c: inconsistent -> consistent |
| response | The response key pressed (e.g. 18=E or 23=I) script saves the final and -by design- correct response for each trial |
| responseText | The label of the response key (E vs I) |
| correct | The accuracy of the initial response 0 = initial response was incorrect and needed to be corrected 1 = initial response is correct |
| latency | The latency of the final (correct) response in ms; measured from onset of stim |
| stimulusNumber | The number of the current stimulus |
| stimulusItem | The currently presented item |
| da | D-score of the first short blocks (Only meaningful for the last row of data in the raw data file - upon completion of IAT) |
| db | D-score of the second long blocks (Only meaningful for the last row of data in the raw data file - upon completion of IAT) |
| d | Overall d-score (non-weighted mean of the 2 d-scores); main DV (Only meaningful for the last row of data in the raw data file - upon completion of IAT) Suggested Interpretation D-score <= -0.65 => "a strong" preference for hypothesis-NONconforming pairings D-score < -0.35 => "a moderate" preference for hypothesis-NONconforming pairings D-score < -0.15 => "a slight" preference for hypothesis-NONforming pairings -0.15 <= D-score <= 0.15 "little to no" preference D-score > 0.15 => "a slight" preference for hypothesis-conforming pairings D-score > 0.35 => "a moderate" preference for hypothesis-conforming pairings D-score >= 0.65 => "a strong" preference for hypothesis-conforming pairings |
| percentCorrect | The overall percent correct score of initial responses in test trials of D-score qualifying latencies (Only meaningful for the last row of data in the raw data file - upon completion of IAT) |
| propRT300 | The proportion of response latencies < 300ms (Only meaningful for the last row of data in the raw data file - upon completion of IAT) |
| excludeCriteriaMet | 1 = yes, exclusion supported per Greenwald et al (2003, p.214, Table 4): (Only meaningful for the last row of data in the raw data file - upon completion of IAT) More than 10% of all response latencies are faster than 300ms 0 = otherwise |
The procedure can be adjusted by setting the following parameters.
| Name | Description | Default |
|---|---|---|
| showSummaryFeedback | Set parameter showsummaryfeedback = true to display summary feedback to participants at the end set parameter showsummaryfeedback = false if no summary feedback should be presented to participants | true |
| isi | Interstimulus interval (in ms) | 250 |