A Swiss study has seemingly found a correlation between smartphone use for calls and decreased memory performance or memory loss in adolescents. Smartphones, just like the mobile phones of yesteryear, emit radiation that's used to pull and push data, voice and other connections. This radiation, according to the study, can affect the brain when a phone is held to somebody's ear. Adolescents, a crowd whose brains are in one of the biggest developmental stages of their lifetimes, are especially susceptible. The study focused on memory, and found that the majority of memory issues came from right-handed teens who made a lot of phone calls. To put the findings to numbers, the study involved 700 students aged 12 to 17. These students were given an initial assessment, then a follow-up one year later. Students who made a lot of calls on their smartphones generally ended up scoring lower on the follow-up assessment.
There are a long list of caveats for this study, but what preliminary findings point to is that when the right side of your brain is exposed to a large amount of radiation from making calls on a smartphone over a long period of time, memory performance may degrade. The study was only done with adolescents, as the first caveat. This means that adults with fully developed brains may be in less danger of memory loss, while children whose brains are still physically developing at a rapid pace may see worse memory loss or other ill effects. None of this can be confirmed without further research, of course, and the initial study used a relatively small population subset.
The study found something a bit strange; exposure to lots of data traffic, as reported by students who mainly used their phones for gaming, entertainment and other use cases instead of making calls, actually seemed to increase scores. This could be the effects of puberty, of course, offset by radiation in those whose scores did not grow much or even shrank. As the study states quite plainly, due to the limited population subset and control conditions, all of the information in the study should be taken as a means to continue research with similar studies in other populations and under different conditions.