My hypothesis is that YouTube Shorts bump more information from your short-term memory than images. I think watching short clips makes it more difficult for your brain to keep information in short-term memory. This is because these videos are made to be highly engaging, short and give instant satisfaction.

In my research I found something called "digital dopamine," which describes how watching short clips releases a hormone in your brain that makes you feel good but it can be very addictive. Then, I found an article called "Short video addiction and its impact on cognitive functioning in adolescents and youth" from 2026. I asked my aunt, who is a neurologist, about how I could test the effect of Shorts on people's memory. She suggested to ask them to memorize a few numbers, and, after a short distraction, ask them to recall as many as they could. So that's what I decided to do.

Independent:

• Age of participant
• Type of distraction: video or image

Dependent:

• Accuracy: how many numbers where recalled correctly
• Recall time: how much time did it take to recall the numbers

Controlled:

• 10 seconds to watch the distraction
• 5 seconds to memorize the numbers

1. Ask a participant to memorize 7 numbers within 5 seconds.
2. Either show them a YouTube short or a still image for 10 seconds.
3. Ask them to recall the numbers.
4. Record the accuracy and recall time.

Create a web app using Google Firebase to do the steps in the procedure. I used Google Gemini to make the first web app (the prototype). Then, I modified the code to work the way I wanted and changed the style.

The data was collected in a Firebase database, which I downloaded and opened with Google Sheets. I used Gemini to help me calculate average accuracy and recall time. I used Google Sheets to create graphs of my data.

There were 41 participants in age group 6 to 10 and 41 participants in age group 11 to 15. About half of the participants saw an image and the other saw a video. There were only 7 participants in the age group 16 or older, so the data was not included in the analysis.

Two experiments were completed in the school library on one computer, monitored by the school librarian. There were 15 students from grade 5 and about 15 students from grade 3. The other experiment was done in my grade 6 class, monitored by the teacher, and included 34 students taking the recall test at the same time on separate computers.

The average accuracy of participants in group 6 to 10 was 52.17% if they saw an image and 43.65% if they saw a video. The average accuracy of participants in group 11 to 15 was 74.53% if they saw an image and 61.90% if they saw a video. The average recall time of participants in group 6 to 10 was 18.63s if they saw an image and 19.66s if they saw a video. The average recall time of participants in group 11 to 15 was 13.49s if they saw an image and 13.88s if they saw a video. The average accuracy per digit was almost the same for digits 1, 2, 4, and 5 for both age groups and type of distraction. The average accuracy per digit was lower for participants that watched a video for digits 3, 6, and 7.

Accuracy scores suggest that watching YouTube shorts has an effect on short-term memory for age groups 6 to 10 and 11 to 15. Overall accuracy was highest for the first three digits. Participants that watched a YouTube short had decreased accuracy for the 3rd, 6th and 7th digits. Why the 3rd digit?

Average recall time was not affected by the distractor type. For age group 6 to 10, there was a small increase in recall time after watching a YouTube short.

Raise awareness of the effects of watching short videos like YouTube shorts and TikTok on short-term memory. My web app can be used for further study. Redoing the test for ages 16 or older to get more samples would be interesting.

Two people looked away from the YouTube short. The web app showed the previous answers on a Chromebook which messed up some of the smaller kids thinking that they had to choose an answer from those options that other people wrote before them even though they were supposed to type in there own answer.

Cleveland Clinic (2024). Short-Term Memory: What It Is & How It Works. https://my.clevelandclinic.org/health/articles/short-term-memory.

Mona, A. E., Roshith, V., Peter, R., Roy, P., Hassan, A., Devika, M., & Trishala, M. (2026). Short video addiction and its impact on cognitive functioning in adolescents and youth: a systematic review. International Journal of Adolescence and Youth, 31(1).

Veritasium YouTube Channel, https://www.youtube.com/@veritasium/shorts

Lorem Picsum, https://picsum.photos/, [random image retrieval].

Firebase Documentation. "Firebase," Google. https://firebase.google.com/docs.

Google. (2025). Gemini [Large language model]. https://gemini.google.com/

Thank you to Alicja Cieslak for helping with methods, Mik Cieslak for help with programming, Amy Cieslak and Mme. Jasmine for help with testing, Mr. Jan Owoc and the other St. Luke Science Fair judges for feedback, and to all the participants!