A respected Swiss scientist, Conrad Gessner, might have been the first to raise the alarm about the effects of information overload. In a landmark book, he described how the modern world overwhelmed people with data and that this overabundance was both "confusing and harmful" to the mind. [...] It's worth noting that Gessner, for his part, never once used e-mail and was completely ignorant about computers. That's not because he was a technophobe but because he died in 1565. His warnings referred to the seemingly unmanageable flood of information unleashed by the printing press.

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To date, studies suggest there is no consistent evidence that the Internet causes mental problems. If anything, the data show that people who use social networking sites actually tend to have better offline social lives, while those who play computer games are better than nongamers at absorbing and reacting to information with no loss of accuracy or increased impulsiveness.