... their brain works more.
That's all there is to it. Age, searching, internet, none of that is relevant other than being conditions under which it can happen. Identical results can be had with kids doing stem completion tasks (E A _ _ _ = E A R T H), college students doing a Stroop task (words naming colors, in that color or a different one), and any brain you can get to sit still and problem solve while stuck inside a tube with horrible noises going on.
TFA is a prime example of someone doing a far too specific test on a general principle and either thinking or pretending to have discovered something. I'm going to go with "pretending" since the new results after practice were seen in the middle and interior frontal gyri, and he claims these results are due to two specific processing tasks, but neglects to mention that the two regions make up more than half the frontal lobes in which there are obviously a great number of things going on, many of which would be occurring during the task, their design is completely incapable of telling the difference between excitatory and inhibitory activation, and there is no word on whether the 'enhanced' neural activity correlated with improved ability to search and/or answer relevant questions, without which one could just as easily make a case that the increased activation was a sign of boredom for having to do the same damn stuff again that they've been doing the past two weeks at home.
Someone needs to do a study and see whether asking hard questions about this stuff of researchers giving talks on it when they clearly don't know enough about what they're doing makes their brains light up in the right places, because if you make people think, their brain works harder. Wouldn't have happened here, because they wouldn't have been forced to answer the questions -- this was just a poster. Anyone can get any poster into one of these conferences as long as it says fMRI on it.
I teach elderly people how to use the internet along with other computer skills. It actually does help them as unlike simply learning something new, the internet and computer skills quickly leads onto a range of other skills that they can pick up quickly by themselves. If you think young people are good at picking up computer skills you should try working in primary schools with mainly young women teachers. Most can hardly get past simple word processing. The difficulty of teaching the elderly in not to do with their brain power but they are not motivated enough to want to learn as they have few others to impress. I also teach martial arts, scuba diving, bebop guitar, and DIY skills. Mainly to younger people - who want life pout on a plate for them. Oh yes, I'm 79 you can check out who I am by looking up my various web sites on how to make movies, for children.