Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond
Created: January 06, 2021
Last Modified: January 19, 2025 by K. Borchert (katjab@millisecond.com), Millisecond
Script Copyright © Millisecond Software, LLC
This script implements a Chimeric Faces Procedure similar to the one used by the Behavioural Laterality Battery (Parker et al, 2020). The Chimeric Face Task assesses the lateralisation of emotion processing in faces.
https://gorilla.sc/openmaterials/104636
Innes, R. B., Burt, D. M., Birch, Y. K. & Hausmann, M. (2016). A leftward bias however you look at it: Revisiting the emotional chimeric face task as a tool for measuring emotion lateralization. Laterality, 21, 643-661. https://doi.org/10.1080/1357650X.2015.1117095
10 minutes
Participants view chimeric faces (different emotion on left and right side of face) for a short duration and have to select from 4 possible emotions (anger, disgust, happiness, sadness) which emotion was the strongest emotion displayed.
(1) Intro*
(2) Practice: 8 trials
- 8 different images using 'surprise' and 'fear' as the emotions
- order of images randomly determined
(3) Test: 4 test blocks (see Editable Parameters)
- 16 images (4 per emotion: angerleft, disgustleft, happyleft, sadleft) are run twice per block = 32 trials
- order of images randomly determined ( the same image can be run consecutively)
Trial Sequence:
-Fixation Cross for 1000ms (editable parameter)
-image for 500ms (editable parameters)
-max response time: 10000ms (editable parameters)
• the Inquisit script does NOT run a sizing procedure for the stimuli as done by Parker et al (2020)
The images are presented with a 7cm height (as based on the height the images roughly appeared
in the Parker et al, 2020, Chimeric Demo task after completion of the resizing procedure).
If the current screen is NOT big enough to present the image with these default dimensions,
the largest possible size for the current screen is created (the image size used is noted in the data files).
the stimuli are provided by the Behavioural Laterality Battery (Parker et al 2020)
and can be downloaded at:
https://osf.io/4bqe6/
if used, please cite reference articles.
provided by Millisecond. The instructions are based on the ones used by
the Behavioural Laterality Battery (Parker et al 2020).
The instructions can edited in the provided htm-files.
File Name: chimericfaces_summary*.iqdat
| Name | Description |
|---|---|
| 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 |
| heightFaceImagesMM | The height of the face images used (if screen allows, the image height should be -by default- 70mm) |
| propCorrectOverall | The proportion of correct emotion selections (correct = either one of the presented emotions was selected) across all test trials |
| meanCorrRTOverall | The mean response time of selecting a correct emotion across all test trials |
Chimeric Faces: Ch |
|
| countChLR | Counts the number of times the (correct) left emotion in the presented image was selected |
| countChRR | Counts the number of times the (correct) right emotion in the presented image was selected |
| countChIR | Counts the number of times an unrelated emotion for the presented image was selected |
| countChNR | Counts the number of times a no response was collected |
Separate For Each Emotion |
|
| countAngerLeftChLR | Counts the number of times the (correct) left emotion ('anger') in the presented angerleft-image was selected |
| countAngerLeftChRR | Counts the number of times the (correct) right emotion (different from anger) in the presented angerleft-image was selected |
| countAngerLeftChIR | Counts the number of times an unrelated emotion was selected for an angerleft-image |
| countAngerLeftChNR | Counts the number of times no response was made for an angerleft-image (same for disgustleft, happyleft, sadleft images) |
Control Faces: Ctrl (Show The Same Emotion On Both Sides) |
|
| countCtrlCR | Counts the number of times the correct emotion was selected |
| countCtrlIR | Counts the number of times the incorrect emotion was selected |
| countCtrlNR | Counts the number of no responses collected |
Separate For Each Emotion |
|
| countAngerLeftCtrlCR | Counts the number of times the emotion 'anger' was selected for anger control images ( anger presented on both sides) |
| countAngerLeftCtrlIR | Counts the number of times an incorrect emotion was selected for anger control images ( anger presented on both sides) |
| countAngerLeftCtrlNR | Counts the number of times no responses were selected for anger control images ( anger presented on both sides) (same for disgust, happy, sad control images) |
File Name: chimericfaces_raw*.iqdat
| Name | Description |
|---|---|
| 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 |
| heightFaceImagesMM | The height of the face images used (if screen allows, the image height should be -by default- 70mm) |
| blockCode | Name of the current block |
| blockNum | Number of the current block |
| trialCode | Name of the current trial |
| trialNum | Number of the current trial |
| testBlockCounter | Counts the test blocks run |
| index | The currently selected itemnumber of the presented image 0-based selection (first item has index = 0) |
| stim | The presented image |
| leftEmotion | The left emotion in the presented image |
| rightEmotion | The right emotion in the presented image |
| chimericCategory | 1 = control condition (both sides show the same image) 2 = chimeric condition (different emotions on left and right side) |
| response | The selected response button (no response = 0) |
| selectedEmotion | The selected emotion (no response = 0) |
| selectedFaceLaterality | Left, right, none (= for incorrect emotion selections as well as no responses) by default, if participants select the correct emotion for control (=only one emotion) images 'selectedFaceSide' will be 'left' |
| correct | 1 = either one of the presented emotions was selected; 0 = otherwise |
| latency | The response latency (in ms); measured from: onset of image |
The procedure can be adjusted by setting the following parameters.
| Name | Description | Default |
|---|---|---|
| fixationDuration | The fixation cross duration (in ms) | 1000 |
| imageDuration | The image duration (in ms) | 500 |
| maxResponseTime | The max. response time in ms | 10000 |
| heightFaceImagesMM | The height of the faces in mm ( based on size of images in blb task when the screen was sized for credit card) | 70 |
| fixationHeightMM | The height of the fixation cross stimulus in mm | 20 |
| numberTestBlocks | The number of test blocks to run ( each test block runs 32 trials = 16 images x 2) | 4 |