Yeah, good point. It annoys me any time this topic comes up (which is fairly often in my life, since I recently had kids) that I don't have a better set of references to back me up.

It was decades ago that I studied journalism in college, and I can't find links to a lot of what I learned, including the deleterious influence of television on human development (especially children).

Today, the American Academy of Pediatrics recommends[1], "Television and other entertainment media should be avoided for infants and children under age 2." We have pediatric doctors like Dr. Dimitri Christakis doing interesting research to help demonstrate the harms[2].

But I don't have much time to really follow it these days (aforementioned young kids and all...). At the same time, when I hear "show me the evidence! there's no proof TV is harmful to 2-year olds!" it really bugs me. (Not implying that's what you are saying, it's jut something I hear a lot.)

It's like one of those "there's no proof dogs have emotions!" things. It's obvious when you watch little kids with TV and heavy and mostly-unrestricted iPad/Nintendo. It's obvious that is not how you should do it (very much). I can't prove it, but I am certainly going to act on that conclusion with my own kids.

So, to answer your question, the reason I deny my 2-year-old TV and unsupervised iPad use is because I have observed it in him, and observed it in his peers, and it's just my best judgement that it is better off waiting until later.

Example 1: One morning I came downstairs and he was watching TV. He had turned it on by himself; it was an unusual morning in that my wife and I both slept in. He was just sitting there, in a kind of stupor, staring motionless at the TV with a kind of slack jawed empty expression (like my own, probably, when I drink beer and watch True Detective after everybody is in bed). I walked in and he didn't even respond. (The show was roughly the Japanese equivalent of Sesame Street.) I cleared my throat. No response. I grabbed the remote, and jokingly pointed it him from behind (the joke was for my wife, who had just walked in also). With the click! of the TV going off, my son immediately stood up, looked around, and busied himself with his Brio train set (which is what he usually did in the morning at that age (right around 2)). It appeared as if I had used the remote to turn him on.

Example 2: We experimented with letting him have limited access to Mom's iPhone, especially she started nursing our second child. For the usual reason -- it made him a lot easier to deal with while Mom did an unrelated but important task. He did these little 'educational' games where you build a train track and then the trains run on it, and you have to build around obstacles, etc. But we soon noticed that when we would take the iPhone back, he would have a very violent negative reaction -- really unlike him, we felt. All kids have tantrums and taking away a toy is always a risk of creating a situation, but we both felt that his behavior seemed unhealthy in some way; to exaggerate a little, it seemed like he was addicted to the little game. In that same vein, when we let him do it for as long as he liked, he would keep doing it over and over until he worked himself into a similar state. E.g., after an hour of doing it he would get so frustrated by the train track building not going well that he would have a similar tantrum of screaming and being very upset. He had this same kind of frustration with the real laws of the physical world, too -- like the wooden block too big for the hole he was trying to fit it in -- but those moments seemed much more short-lived than the iPhone-related ones. (And it wasn't just games -- interacting with the OS itself (dragging apps around, opening things to see what they did) seemed fascinating to him, but also seemed like a laser-pointer-and-kitten thing where he would get too worked up and couldn't stop himself.)

Example 3: My friends who disagree with me about this and let their 3-year olds watch TV hours every day have more annoying and obnoxious kids than those who don't. ;-) Bad impulse control, lower ability to accept and move on when things don't go their way, etc.

Also, I should clarify that we don't blanket ban TV and iPad. It's not an absolute, just a general rule.

With iPad especially, there's a whole lot of potential good stuff there, too. We let him use the iPad when we are supervising, or just sitting with him if he is in one of the painting or music apps. He's pretty awesome at Garage Band, and incredible using EasyBeats. He does a lot of painting in Paper and apps like that. And although he is not allowed to, he is a small and clever homo sapiens and therefore predictably manages to sneak a substantial amount of screen time, whenever somebody leaves an table or phone around with an easily-guessed password.

With TV, we watch NHK news around him -- he doesn't tune in to it. We had to stop watching the news channels with commercials though; as soon as one would come on, you could see him stop building his Duplo block tower and swivel his head to focus on the TV.

I do let him sit down and watch UFC fights with me, though -- that is the hypocrisy that proves the earnestness of my intentions.

[1]: https://www.aap.org/en-us/advocacy-and-policy/aap-health-ini...

[2]: http://www.medicaldaily.com/interview-dr-dimitri-christakis-...