How to Beat Smartphone Addiction: A 3-Day Brain Study
A research team in Germany studied what happens when people dramatically cut back smartphone use for 72 hours—allowing only essential communication and necessary tasks.
The study included 25 young adults (about ages 18–30). Participants completed questionnaires and underwent brain scans, then repeated testing after the 3-day restriction period.
During fMRI testing, participants were shown different types of images, including smartphone-related cues and neutral images. After the restriction period, their brains showed measurable shifts in cue-related responses, especially in networks involved in craving, reward processing, salience, and self-control.
The researchers interpreted these shifts as resembling how the brain can react to reward cues in other habit-forming behaviors—meaning the brain may become more sensitive to phone-related triggers, at least temporarily, when access is restricted.
Importantly, the “dopamine and serotonin” angle comes from linking the observed brain-activation changes to dopamine- and serotonin-related receptor probability maps (a brain-mapping method used to infer which neurotransmitter systems may be involved). This supports the idea that these neurotransmitter systems could be part of the response, even though the study is not the same as directly measuring dopamine or serotonin levels in the body.
Because the sample was relatively small and the time window was short, the findings are best viewed as early evidence that even a brief “phone diet” can shift how the brain reacts to smartphone cues—rather than proof of long-term rewiring for everyone.