PeakAffectDS

Contact Information

If you would like further information about PeakAffectDS, to purchase a commercial license, or if you experience any issues downloading files, please contact us at peakaffectds@gmail.com.

Description

PeakAffectDS contains 663 files (total size: 1.84 GB), consisting of 612 physiology files, and 51 perceptual rating files. The dataset contains 51 untrained research participants (39 female, 12 male), who had their body physiology recorded while watching movie clips validated to induce strong emotional reactions. Emotional conditions included: calm, happy, sad, angry, fearful, and disgust; along with baseline a neutral condition. Four physiology channels were recorded with a Biopac MP36 system: two facial muscles with fEMG (zygomaticus major, corrugator supercilii) using Ag/AgCl electrodes, heart activity with ECG using a 1-Lead, Lead II configuration, and respiration with a wearable strain-gauge belt. While viewing movie clips, participants indicated in real-time when they experienced a "peak" emotional event, including: chills, tears, or the startle reflex. After each clip, participants further rated their felt emotional state using a forced-choice categorical response measure, along with their felt Arousal and Valence. All data are provided in plaintext (.csv) format.

PeakAffectDS was created in the Affective Data Science Lab.

Physiology files

Each participant has 12 .CSV physiology files, consisting of 6 Emotional conditions, and 6 Neutral baseline conditions. All physiology channels were recorded at 2000 Hz. A 50Hz notch filter was then applied to fEMG and ECG channels to remove mains hum. Each .CSV file contains 6 columns, in order from left to right:

1. Sample timestamp (units: seconds)
2. EMG Zygomaticus (units: millivolts)
3. EMG Corrugator (units: millivolts)
4. ECG (units: millivolts)
5. Peak event makers: 0 = no event, 1 = chills, 2 = tears, 3 = startle

Perceptual files

There are 51 perceptual ratings files, one for each participant. Each .CSV file contains 4 columns, in order from left to right:

1. Filename of presented stimulus (see File naming Convention, below)
2. Felt emotional response: 1 = neutral, 2 = calm, 3 = happy, 4 = sad, 5 = angry, 6 = fearful, 7 = disgust
3. Felt Valence, ranging from: 1 = Very negative, to 7 = Very positive
4. Felt Arousal, ranging from: 1 = Very low, to 7 = Very high

File naming convention

Each of the 612 physiology files has a unique filename. The filename consists of a 3-part numerical identifier (e.g., 09-02-03.csv). The first identifier refers to the participant's ID (09), while the remaining two identifiers refer to the stimulus presented for that recording (02-03.mp4); these identifiers define the stimulus characteristics:

• Participant: 01 = participant 1, 02 = participant 2, ..., 51 = participant 51.
• Emotion: 01 = neutral, 02 = calm, 03 = happy, 04 = sad, 05 = angry, 06 = fearful, 07 = disgust.
• Stimulus set. For Emotional files: 01 = group 1, 02 = group 2, 03 = group 3. For Neutral files: 01 = instance 1, 02 = instance 2, ..., 06 = instance 6.

Filename example: 09-02-03.csv

• Participant 9 (09)
• Calm (02)
• Stimulus Set 3 (03)

Filename example: 09-01-05.csv

• Participant 9 (09)
• Neutral (01)
• Instance 5 (05)

Methods

A 1-way mixed-design was used, with a within-subjects factor Emotion (6 levels: Calm, Happy, Sad, Angry, Fearful, Disgust) and a between-subjects factor Stimulus Set (3 levels). Trials were blocked by Affect Condition (Baseline, Emotional), with each participant presented 6 blocked trials: Baseline (neutral), then Emotional (Calm, ..., Disgust). This design reduced potential contamination from preceeding emotional trials, by ensuring that participant's physiology began close to a resting baseline for emotional conditions.

Emotion was presented in pseudorandom order using a carryover balanced generalised Youden design, generated by the crossdes package in R. Eighteen emotional movie clips were used as stimuli, with three instances for each emotion category (6x3). Clips were then grouped into one of three Stimulus Sets, with participants assigned to a given Set using Block randomisation. For example, participants assigned to Stimulus Set 1 (PID: 1, 4, 7, ...) all saw the same movie clips, but these clips differed to those in Sets 2 and 3. Six Neutral baseline movie clips were used as stimuli, with all participants viewing the same neutral clips, with their order also generated with a Youden design.

Stimulus duration varied, with clips lasting several minutes. Lengthy clips without repetition were used to help ensure that participants became engaged, and experienced genuine, strong emotional responses. Participants were instructed to immediately indicate using the keyboard when experiencing a "peak" emotional event, including: chills, tears, or startle. Participants were permitted to indicate multiple events in a single trial, and identified the type of the evens at the trial feedback stage, along with ratings of emotional category, arousal, and valence. The concept of peak physiological events was explained at the beginning of the experiment, but the three states were not described as being associated with any particular emotion or valence.

License information

PeakAffectDS is released under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License, CC BY-NC-SA 4.0.

Citing PeakAffectDS

Greene, N., Livingstone, S. R., & Szymanski, L. (2022). PeakAffectDB [Data set]. Zenodo. https://doi.org/10.5281/zenodo.6403363