"Multitasking erodes cognitive control. We lose our ability to say that this is important, this is unimportant. All we want is new information."
In contrast, when readers open a printed book, "there's nothing else going on except words on a page, no distractions. It helps train us to be deep thinkers."
Carr, 52, told AFP he's not optimistic society will switch off en masse but it's important to look clearly at what it might be losing.
And he doesn't feel quite so lonely now that some other authors and TV programme-makers have tackled the same subject. "There are signs, still sporadic and small, that people are beginning to question the effects of technology."
But Carr said there is little evidence so far of pressure for change.
"I think as a society we're choosing information overload: we're choosing to sacrifice the more meditative and contemplative aspects of our minds."
- with AFP
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