Behavioral Experiment Definitions

Metadata information and experimental setup information for behavioral experiments is saved in beh.json files (see BIDS Specification/Behavioral experiments (with no neural recordings)).

In addition to the fields mentioned the existing BIDS specification, in case of experiments involving eyetracking or visual stimulus, the following fields are REQUIRED:

Table 1: Required StimulusPresentation Information

Key

Description

Data Type

Example Values

StimulusPresentation.ScreenDistance

Distance between the participant’s eye and the screen (in meters).

Number

e.g., 0.7

StimulusPresentation.ScreenOrigin

Location of the spatial coordinates’ origin for the visual stimuli presentation.

Text list

["top","left"], ["center","center"], etc.

StimulusPresentation.ScreenRefreshRate

Refresh rate of the screen (in Hertz)

Number

60

StimulusPresentation.ScreenResolution

Resolution of the screen (in pixels)

Number list

["1024","768"],

StimulusPresentation.ScreenSize

Size of the screen (in meters)

Number list

["0.312","0.226"]

Example of _beh.json sidecar:

{
"Columns": [
    "pupil_size",
    "x_coordinate",
    "y_coordinate"
],
"Manufacturer": "SR-Research",
"ManufacturersModelName": "EYELINK II CL v4.56 Aug 18 2010",
"TaskName": "Delay Fear Conditioning",
"TaskDescription": "Participants are presented with a series of images(CS). Some images(CSp) are followed by an aversive unconditioned stimulus (USp) while others(CSm) are not(USm).",
"CogAtlasID": "https://www.cognitiveatlas.org/task/id/trm_5023ef8eab626/",
"CogPOID": "http://wiki.cogpo.org/index.php?title=Classical_Conditioning_Paradigm",
"SOA": 3.5,
"StimulusPresentation": {
  "ScreenDistance": 700,
  "ScreenOrigin": [
    "top",
    "left"
  ],
  "ScreenRefreshRate": 60,
  "ScreenResolution": [
    1024,
    768
  ],
  "ScreenSize": [
    312.42,
    226.89
  ]
}