Recent quotes:

Self-generated vision inputs suppressed

That's because the brain can tell if visual motion is self-generated, canceling out information that would otherwise make us feel -- and act -- as if the world was whirling around us. It's an astonishing bit of neural computation -- one that Maimon and his team are attempting to decode in fruit flies. And the results of their most recent investigations, published in Cell on January 5, provide fresh insights into how the brain processes visual information to control behavior. Each time you shift your gaze (and you do so several times a second), the brain sends a command to the eyes to move. But a copy of that command is issued internally to the brain's own visual system, as well. This allows the brain to predict that it is about to receive a flood of visual information resulting from the body's own movement -- and to compensate for it by suppressing or enhancing the activity of particular neurons.

Twitter is polluted and getting worse

Even though I follow people I like and respect, there’s no way around seeing some of the crap that happens on Twitter. Even if you don’t use Twitter at all, you will have seen articles about people being harrassed and threatened. You will have noticed the pure toxic sludge that pours through the service. (A hypothetical “Dawn of the Idiocracy” prequel would feature Twitter prominently.) And it’s worse than any blog comments system, because if you use it, anybody can put something in front of your face whether you want it or not. Twitter is also wonderful, and I get so much value out of it. But it’s like 51% good and 49% bad. I don’t see it getting any better. Hopefully it can hold the line at just-barely-worth-it. (But the recent changes to the timeline make that a little less likely.)

Even smart people start shouting amid Twitter's noise.

My feed (full of people I admire) is mostly just a loud, stupid, sad place. Basically: a mirror to the world we made that I don’t want to look into. The common way to refute my complaint is to say that I’m following the wrong people. I think I’m following the right people, I’m just seeing the worst side of them while they’re stuck in an inhospitable environment. It’s exasperating to be stuck in a stream.

Twitter too noisy

But what I’ve come to call Big Twitter is simply not a place for conversation any more. I don’t like this change. I made friends — real friends — on Twitter when it was a place for conversation. I reconnected with people I had lost touch with. Whole new realms of knowledge were opened to me. I don’t want to foreclose on the possibility of further discovery, but the signal-to-noise ration is so bad now that I don’t think I could pick out the constructive and interesting voices from all the mean-spiritedness and incomprehension; and so few smart people now dare to use Twitter in the old open way. Big Twitter was great — for a while. But now it’s over, and it’s time to move on. I’m just hoping that some smart people out there are learning from what went wrong and developing social networks that can strengthen the signal and silence the noise.