We still don't know what long-term exposure to highly condensed, highly customized information does to our brains and social systems as a whole.
For example, there are signs that social network users are actually unhappy - in other words - are experiencing all kinds of mental health issues.
It is well known that programmers experience "burn outs", which, from personal experience, is a terrible and debilitating state sometimes even leading to suicide.
There is addiction to gaming, chat, porn, social networks.
Mobile phones have exposed everyone to the infinite stream of information/communication and I think this will lead to many more mental health issues.
I think we are not yet prepared for the kind of impact that current and future tech will have on our minds, so this would be a worthy field to invest in now.
The idea of people spending 10+ hours in VR per week scares me, but it's probably pretty similar to video game and smartphone usage. Maybe that would be a good place to start research.
A little over a month ago I started working on forming new habits, severely limiting use of network tools. I now only check email/sms/etc twice per day. At 6pm I put all technology away. I'm asleep by 9:30pm, awake at 5:30am, and try not to look at any network tools again until 10am. I'm considerably happier and more productive now. It's a tough habit to maintain and I'm pretty sure a few of my friends think I'm nuts.
A couple good, related reads: http://www.amazon.com/Deep-Work-Focused-Success-Distracted/d... http://www.newyorker.com/books/page-turner/the-useless-agony...
If YC or anyone else wants to fund me, I'd be fine with that.