Press "Enter" to skip to content

Tutorial: Relative Duration for the Background_Audio Response

FindingFive recently rolled out a new feature that allows you to specify the duration of a background audio response relative to the duration of a stimulus on the same trial (e.g., an audio or video stimulus). This is really useful when your audio or video stimulus files vary in duration, and you would like to record participants adaptively – longer for longer stimuli and shorter for shorter stimuli.

Because recording background audio relative to the duration of your stimuli involves both a background audio response and a series of stimuli, implementing this feature involves making edits to both. Specifically, you must 1) add the "group" property to your stimuli definitions and 2) add the "duration" property to your response. Keep reading to find out more!

Adding “group” Property to Stimuli Definitions

Let’s say one block of your study involves a series of eight trials, each with an audio stimulus paired with a background audio response. The first step is to add the “group” property to each of those eight stimuli, marking them as part of the same unit. This step clues FindingFive into which stimuli to pay attention to when changing the duration of the background audio response.

For example, in the below definition for a stimulus, we added the "group" property, assigning this stimulus to the group called "audio_group1":

  "content": "slow_spring_board.mp3",
  "type": "audio", 
  "group": "audio_group1"

You would then continue to add the code "group": "audio_group1" to all eight stimuli definitions.

For more details on defining a stimulus, check out our crash course and study grammar.

Adding “duration” Property in Response Definitions

When all the stimuli have been tagged using the "group" property, the next step is to set the duration of the background audio response. To do this, add the "duration" property to your background audio response, and we’ll use some fancy notation to set it relative to the duration of the stimuli.

This fancy notation looks as follows: "duration": "%sgroup:insert_group_name+insert_seconds". As you can tell, you must insert both the name of the group as defined in your stimuli definitions and the number of additional seconds that you’d like to record following each stimulus presentation.

In the below example, we’ve added the "duration" property to the background audio response that is associated with the "audio_group1" stimulus group defined above. By pairing the stimulus group to this background audio response, the response will record audio for an additional 3 seconds following each stimulus.

  "type": "background_audio",
  "volume_visualizer": true,
  "duration": "%sgroup:audio_group1+3.0"

With these two steps implemented, your background audio response will record audio for a duration that is relative to the duration of your stimuli!

We hope you like this feature! Please feel free to reach out with questions on our forum or at