PsPM-ViS dataset
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Repository Version: 2020.07.07

This dataset contains skin conductance responses (SCR), electrocardyogram (ECG), respiration, pupil size (PSR), and gaze coordinates measurements for 29 healthy unmedicated participants (17 females and 12 males aged 25.3 +/- 3.7) participating in a a classical (Pavlovian) discriminant delay fear conditioning experiment with 3 blocks. CSs are 2 full-screen patterns of approximately equal brightness, contrast, and spatial frequency. US was a train of electric square pulses delivered with a constant current stimulator on participants' dominant forearm through a pin-cathod/ring-anode configuration. SOA between the CS and US was 3.5 s. The first 2 blocks were fear acquisition, with 15 CS+US+, 15 CS+US-, and 30 CS- in each block, and the last block was an extinction phase with 20 CS- and 20 CS+ trials without US delivery. The order of trials in each block was randomized. No fixation cross was presented during CS. During ITI, a black fixation cross was presented in the center of a grey background (RGB 0.7, 0.7, 0.7). ITI was randomly determined on each trial to be an integer between 7 - 11 s. The blocks were recorded on the same day with self-paced breaks.

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This repository is curated by the PsPM team, bachlab.org/pspm

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Dataset is described and used in following references:
- Yanfang Xia & Filip Melinscak & Dominik R. Bach (2020) Saccadic scanpath length: an index for human threat conditioning. Behav Res (2020). DOI:10.3758/s13428-020-01490-5

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File Structure:
- README.txt              // This document
- excludes.txt            // Information on subjects excluded from certain publications
- Data                    // Folder Containing all data files
  - ViS_wdq_XX_snY.mat    // 29 files holding measurements for SCR, ECG, respiration
  - ViS_pupil_XX_snY.mat  // 29 files holding measurements for eye-tracker
  - ViS_cogent_XX_snY.mat // 29 files holding key presses, CS/US information and demographics

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Data Files:
- Files holding SCR, ECG, respiration traces and time markers, recorded with WDQ software.
  - Skin conductance (channel 1)
  - Electrocardiogram (channel 2)
  - Respiration (channel 3)
  - Event markers used for synchronization with Cogent files, markers are set at CS presentation onset (channel 4)
- Files holding pupil traces and time markers, recorded with Eyelink software.
   - Event markers used for synchronization with Cogent files, marker are set at CS presentation onset (channel 1)
   - Pupil size for left pupil (channel 2)
   - Gaze coordinate x for left pupil (channel 3)
   - Gaze coordinate y for left pupil (channel 4)
   - Pupil size for right pupil (channel 5)
   - Gaze coordinate x for right pupil (channel 6)
   - Gaze coordinate y for right pupil (channel 7)
- Files holding keyboard presses and CS/US information, recorded with Cogent 2000 software. Also contains demographic (age, sex, group). The field subject.group indicates the assignment of CS+/- to stimulus patterns.

The data file name is composed of:
- ViS                The dataset name
- wdq/pupil/cogent   The type of data recorded (see above)
- XX                 The subject number
- Y                  The session number

Data are stored as .mat files for use with MATLAB (The MathWorks Inc., Natick, USA) in a format readable by the PsPM toolbox (bachlab.org/pspm). All Matlab files are saved in MATLAB 9.5 (R2018b) format.