Though i'm no scientist - and i'd certainly word it a bit differently - i share these sentiments about twitter. To be clear, I think there are many positive aspects of twitter too, but this is certainly one of my criticisms/concerns.

I recommend reading the rest of this article...it's thought provoking and insightful about how different sources of entertainment and communication affect us (Twitter, Facebook, video games, etc.)

It's just like a newspaper at hyper-speed. You can just read the headlines if you want or you can dig deeper and click through for the rest. The negative is more likely a symptom of laziness in an anti-thinking society.