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Behavioral experiments (with no neural recordings)



In addition to logs from behavioral experiments performed alongside imaging data acquisitions, one can also include data from experiments performed with no neural recordings. The results of those experiments can be stored in the beh directory using the same formats for event timing (_events.tsv), metadata (_events.json), physiological (_physio.tsv.gz, _physio.json) and other continuous recordings (_stim.tsv.gz, _stim.json) as for tasks performed during MRI, electrophysiological or other neural recordings. Additionally, events files that do not include the mandatory onset and duration columns can still be included, but should be labeled _beh.tsv rather than _events.tsv.

Each task has a unique label that MUST only consist of letters and/or numbers (other characters, including spaces and underscores, are not allowed) with the task-<label> entity. Those labels MUST be consistent across subjects and sessions.

The OPTIONAL acq-<label> entity corresponds to a custom label to distinguish different conditions present during multiple runs of the same task. For example, if a study includes runs of an n-back task, with deep brain stimulation turned on or off, the data files may be labelled sub-01_task-nback_acq-dbson_beh.tsv and sub-01_task-nback_acq-dbsoff_beh.tsv.

In addition to the metadata that is either:

  • RECOMMENDED for sidecar JSON files for tabular data, or

  • REQUIRED for some data that can be found in the beh directory (for example SamplingFrequency and StartTime for *_<physio|stim>.tsv.gz files),

it is RECOMMENDED to add the following metadata to the JSON files of this directory:

Key name Requirement Level Data type Description
CogAtlasID RECOMMENDED string URI of the corresponding Cognitive Atlas Task term.
CogPOID RECOMMENDED string URI of the corresponding CogPO term.
InstitutionAddress RECOMMENDED string The address of the institution in charge of the equipment that produced the measurements.
InstitutionName RECOMMENDED string The name of the institution in charge of the equipment that produced the measurements.
InstitutionalDepartmentName RECOMMENDED string The department in the institution in charge of the equipment that produced the measurements.
Instructions RECOMMENDED string Text of the instructions given to participants before the recording.
TaskDescription RECOMMENDED string Longer description of the task.
TaskName RECOMMENDED string Name of the task. No two tasks should have the same name. The task label included in the file name is derived from this "TaskName" field by removing all non-alphanumeric ([a-zA-Z0-9]) characters. For example "TaskName" "faces n-back" will correspond to task label facesnback.

Example of the content of a _beh.tsv and its accompanying _beh.json sidecar file:

trial   response    response_time   stim_file
congruent   red 1.435   images/word-red_color-red.jpg
incongruent red 1.739   images/word-red_color-blue.jpg

In the accompanying JSON sidecar, the trial column might be documented as follows:

   "TaskName": "Stroop",
   "trial": {
      "LongName": "Trial name",
      "Description": "Indicator of the type of trial",
      "Levels": {
         "congruent": "Word and font color match.",
         "incongruent": "Word and font color do not match."