There are two broad types of meditation: concentration, and reflection. I can see how e.g. video games could be a kind of concentration practice. The benefit of deliberate meditation concentration practice is that you learn to apply concentration in non-stimulating circumstances (or rather, you learn that you don't need graphics, meaningful choices, tight timing, or points to stimulate your alertness). Most beginner meditation falls under concentration (brain-settling) practices.
Then there is the reflection/insight practice, in which your mind pays deliberate attention to its own internal machinations. With the right touch--neither too tight, nor too loose--you can maintain an appropriate distance so that you can see what's going on, but not get pulled under. I find it difficult to believe that any activity other than mental reflection, no matter how focused, would be an effective substitute.
The article you provided doesn't back up the claim that playing video games has the same effect on the prefrontal cortex as meditation.
1. It discusses video games that were created with a specific purpose of improving ability to focus.
2. It mentions that researchers have a hypothesis that these games will improve ability to focus.
3. It mentions that there is an ongoing research into what's happening in the brain when people play these games.
I don't see how you can take this and draw a conclusion that video games have the same effect on the prefrontal cortex as meditation.
And your initial claim was broader than that, you said that "prefrontal cortex activity touted by Kelly McGonigal is achieved through any other focused activity", which appears to be completely baseless.
"I don't see how you can take this and draw a conclusion that video games have the same effect on the prefrontal cortex as meditation."
See below.
"Lots of activities can boost the size of various parts of the pre-frontal cortex – video games, for example – but it’s the disconnection of our mind from its “stress center” that seems to give rise to a range of physical as well as mental health benefits, says Taren."
"Lots of activities can boost the size of various parts of the pre-frontal cortex – video games, for example"
This doesn't mean that:
1. Any activity that requires focus has the same effect on the prefrontal cortex of meditation.
2. Video games have the same effect on the prefrontal cortex as meditation.
Also, using this article to support your position is an interesting choice, given that you have previously said that "There are no proven benefits to meditation" and this article discusses proven benefits of meditation.
Actually, the very quote you provided mentions "range of physical as well as mental health benefits", presumably referring to meditation (or "mindfulness practice").
Then there is the reflection/insight practice, in which your mind pays deliberate attention to its own internal machinations. With the right touch--neither too tight, nor too loose--you can maintain an appropriate distance so that you can see what's going on, but not get pulled under. I find it difficult to believe that any activity other than mental reflection, no matter how focused, would be an effective substitute.