Bubble Popping Task

Background

The "Pop the Bubble" task is an interactive, tablet-based digital game assessing visual-motor abilities and behaviors in children. The game was introduced by Sam Perochon and colleagues in 2023 as a tool with the potential to be used for the screening for early Autism Spectrum Disorder. The game is part of a broader diagnostic application called SenseToKnow, which leverages computer vision, haptics, and machine learning to analyze the behavioral, motor, and attention phenotypes of toddlers (aged 17–36 months) during routine pediatric primary care visits. Typically, early autism screenings rely on parental questionnaires and clinical observations of social communication. The Perochon et al. study introduced the "Pop the Bubble" game to capture potential quantifiable tactile and motor processing styles that show subtle differences from those of neurotypical children. For example, Perochon et al (2023) found that children on the autism spectrum tended to touch the screen at the same rate as a control group but did not successfully pop as many bubbles.

During the "Pop the Bubble" game, children are presented with digital bubbles on a tablet screen and are encouraged to pop them by touching the screen. While the task looks like a simple game to the child, the app operates in the background to capture touch-motor interactions and kinematic data. Specifically, the task measures:

1. Average touch duration (how long a finger stays on the screen)
2. Average applied force (the pressure of the touch)
3. Targeting accuracy (how precisely they hit the center of the bubble)
4. Popping rate (speed and frequency of touch interactions)

Millisecond's "Bubble Popping Task" is inspired by the Perochon et al game design. While its implementation strives to emulate the published game description, it is not an exact replica and differences in computational algorithms as well as the procedure itself will exist. The Millisecond task runs on touch devices such as ipads and Androids and can be used on regular Macs and PC with mouse use. The default implementation runs the task with proportional stimuli sizing; however absolute sizing can be used instead which allows the task to run the same stimuli sizes and distances on each screen.

Task Procedure

The Millisecond "Bubble Popping Task" starts out with a short demo phase during which test administrators are asked to demonstrate the child participant how to pop bubbles with one finger by touching them. The screen is divided into five vertical tracks that each float one bubble at a time. Bubbles start at the bottom and rise to the top at a constant speed (which is editable). The starting vertical coordinate of each bubble is somewhat jiggled, so that balloons don't all appear on screen at the same time. Each bubble 'contains' a little animal that is released when the bubble is popped. If a bubble is popped (with a pop sound) the animal is released and the exact same bubble (with the same animal) appears again at the bottom of the track. If a bubble times out instead (reaching the top without being popped), a different bubble (with a different animal, randomly selected) will float up in the track instead.

After the test administrator has popped three example bubbles, a practice phase starts (the change in phases is announced by a title change at the top of the screen). The practice phase ends when the child participant has independently popped two additional bubbles. Right after the second independent bubble is popped, the 20-second test phase begins automatically. Touch data is collected only during the test phase.

What it Measures

The Bubble Popping Task (BPT) assesses visual-motor behavior in children.

Psychological domains

• Proprioception: The body's ability to sense its own position, movement, and muscle force.
• Visual-Motor Skills and Motor Planning (Praxis): calculating the speed, direction, and stopping point of their finger relative to a moving target.
• Motor Inhibition: The ability to stop a physical movement once it is no longer needed.
• Sustained Visual Attention: Ability to stay focused on the same task for 20 seconds

Main Performance Metrics

The task assesses many variables such as touch duration, touch length and screen exploration rate. The most crucial variable assessed with the highest group differentiation power is

• Popping Rate: Number of bubble pops relative to number of screen touches; main measure of visual-motor accuracy.

Psychiatric Conditions

Perochon's 'Pop the Bubble' game is used with the following patient groups

• Autism Spectrum Disorder (ASD)
• Attention Deficit Hyperactivity Disorder (ADHD)

References

Search Google Scholar for peer-reviewed, published research using the Inquisit Bubble Popping Task.

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Perochon, S., Matias Di Martino, J., Carpenter, K.L.H. et al. A tablet-based game for the assessment of visual motor skills in autistic children. npj Digit. Med. 6, 17 (2023). https://doi.org/10.1038/s41746-023-00762-6

Perochon, S., Di Martino, J. M., Carpenter, K. L. H., Compton, S., Davis, N., Eichner, B., Espinosa, S., Franz, L., Krishnappa Babu, P. R., Sapiro, G., & Dawson, G. (2023). Early detection of autism using digital behavioral phenotyping. Nature Medicine, 29(10), 2489–2497. https://doi.org/10.1038/s41591-023-02574-3

Bowler, A., Arichi, T., Austerberry, C., Fearon, P., & Ronald, A. (2024). A systematic review and meta-analysis of the associations between motor milestone timing and motor development in neurodevelopmental conditions. Neuroscience and Biobehavioral Reviews, 167, Article 105825. https://doi.org/10.1016/j.neubiorev.2024.105825

Shaikh MF, Higley C, Campanile C, Francis R, Panja E, Santacaterina S, Pratesi G and Piaggio D (2026) Serious gaming and eye-tracking for the screening, monitoring, and diagnosis of neurodevelopmental disorders in children: a systematic literature review. Front. Bioeng. Biotechnol. 13:1672718. doi: 10.3389/fbioe.2025.1672718