Teens Average 64 Phone Checks Per School Day, Linking Frequent 'Pickups' to Weakened Cognitive Control

A JAMA study reveals teens check phones up to 144 times during school hours, with frequent checking linked to weakened cognitive and inhibitory control.

By: AXL Media

Published: Mar 13, 2026, 12:47 PM EDT

Source: Information for this report was sourced from JAMA Network Open.

The Biological Vulnerability of the Adolescent Brain

Adolescence is a critical period for neurological development, specifically within the prefrontal cortex—the region responsible for cognitive control and goal-directed behavior. Because this area is still maturing while the brain’s sensitivity to social rewards is at its peak, teens are biologically predisposed to seek the immediate gratification provided by social media. Researchers theorize that frequent smartphone use during school hours interferes with attentional foci and depletes the cognitive resources required for sustained learning, leading to a "bidirectional" relationship where low self-regulation fuels frequent checking, and frequent checking further weakens self-regulation.

Objectively Tracking the School Day To move beyond self-reported data, which is often inaccurate, investigators analyzed 14 days of objective iPhone iOS screen time reports from 79 youths (mean age of 15). The study tracked three primary metrics:

Total Screen Time: Ranging from 8 minutes to 5.3 hours per school day.

Pickups (Phone Checking): Averaging 64 times, with a peak of 144.

Content Type: Social media and entertainment accounted for over 70% of use.