exp-lookit-video-infant-control

Overview

Infant-controlled version of the exp-lookit-video frame. This works the same way as exp-lookit-video except that you can enable the parent to:

  • end the trial by pressing the endTrialKey key

  • hold down the lookawayKey (or the mouse button) to indicate that the child is not looking; the trial will automatically end after the lookaway criterion is met. If a ‘lookawayTone’ is provided, a noise is played while the child is looking away to help the parent know the looking coding is working.

You can disable either of these behaviors by setting the corresponding key to ''.

The frame will still end when it would have anyway if neither of these things happen! For instance, if you would have looped the video for 30 seconds, then after 30 seconds the frame will move on, serving as a “ceiling” on looking time.

Lookaway criterion

You have two options for how to determine when the child has looked away long enough to proceed.

1. Set the lookawayType to "total" to accumulate lookaway time until the child has looked away for a total of lookawayThreshold seconds. (For instance, if the lookawayThreshold is 2, then the trial will end after the child looks away for 0.5s, then 1s, then 0.5s.) 2. Set the lookawayType to "continuous" to require that the child look away for a continuous lookawayThreshold-second interval. (For instance, if the lookawayThreshold is 2, then the child might look away for 1s, 1.5s, and 1s but the trial would continue until she looked away for 2s.)

When looking time is measured

The looking time measurement begins only when the video starts, not while a video connection is established.

If a lookawayKey is defined, lookaways are recorded the entire time the frame is running. However, the looking time measurement only starts once video begins playing (e.g., not during webcam connection). Lookaways at the very start of the video don’t count! If the child is not looking as the video begins, the measurement begins once they look for the first time.

If the trial is paused, parent control of the trial is also paused; the looking time measurement begins fresh when restarting.

Examples

This frame will play through a central video of Kim introducing an apple up to five times. After the first 10 seconds, once the child looks away for more than 2 s total, as coded by the parent holding down the P key, it will proceed.

"play-video-five-times": {
    "kind": "exp-lookit-video-infant-control",
    "lookawayKey": "p",
    "lookawayType": "total",
    "lookawayThreshold": 2,
    "endTrialKey": "",
    "lookawayTone": "noise",
    "lookawayToneVolume": 0.25,
    "showLookawayVisualGuide": true,
    "measurementPeriodDelay": 10,

    "audio": {
        "loop": false,
        "source": "peekaboo"
    },
    "video": {
        "top": 10,
        "left": 25,
        "loop": true,
        "width": 50,
        "source": "cropped_apple"
    },
    "backgroundColor": "white",
    "autoProceed": true,
    "parentTextBlock": {
        "text": "If your child needs a break, just press X to pause!"
    },
    "requiredDuration": 0,
    "requireAudioCount": 0,
    "requireVideoCount": 5,
    "restartAfterPause": true,

    "pauseAudio": "pause",
    "pauseVideo": "attentiongrabber",
    "unpauseAudio": "return_after_pause",
    "pauseKey": " ",

    "doRecording": true,
    "baseDir": "https://www.mit.edu/~kimscott/placeholderstimuli/",
    "audioTypes": [
        "ogg",
        "mp3"
    ],
    "videoTypes": [
        "webm",
        "mp4"
    ]
}

Parameters

The parameters for this frame are the same as for exp-lookit-video, plus the additional parameters provided by the infant-controlled-timing mixin.

Data collected

This frame collects the same data as exp-lookit-video, plus the additional data provided by the infant-controlled-timing mixin.

Events recorded

This frame records the same events as exp-lookit-video, plus the additional events recorded by the infant-controlled-timing mixin.