Nicholas Carr on multitasking:

"The problem today is not that we multitask. We’ve always multitasked. The problem is that we’re always in multitasking mode. The natural busyness of our lives is being amplified by the networked gadgets that constantly send us messages and alerts, bombard us with other bits of important and trivial information, and generally interrupt the train of our thought. The data barrage never lets up. As a result, we devote ever less time to the calmer, more attentive modes of thinking that have always given richness to our intellectual lives and our culture—the modes of thinking that involve concentration, contemplation, reflection, introspection. The less we practice these habits of mind, the more we risk losing them altogether."

Alan Bloom on being distracted as an adult by many technological options:

"The philosopher William James famously wrote of the 'blooming, buzzing confusion' that constitutes sensuous experience for babies, who have not yet developed the filters necessary to organize that experience into discrete and meaningful units, but our daily technologies threaten to return us all to virtual baby-hood." (from "the Pleasures of Reading in an Age of Distraction")

Ken Robinson on ADHD-like distraction as over-stimulus:

“This is the modern epidemic, the plague of ADHD, and it’s fictitious. Don’t mistake me; I don’t mean to say there is no such thing as Attention-Deficit Disorder… What I do know for a fact is it’s not an epidemic. These kids are being medicated as routinely as we had our tonsils taken out, and on the same whimsical basis and for the same reason: medical fashion.

Our children are living in the most intensive stimulating period in the history of the earth. They’re being besieged with information and coerced for attention from every platform: computers, from iPhones, from advertising hoardings, from hundreds of television channels. And we’re penalizing them now for getting distracted. From what? Boring stuff."

Winifred Gallagher on how to staying focused for long periods of time:

“If you really want to focus on something, says Castellanos, the optimum amount of time to spend on it is ninety minutes. "Then change tasks. And watch out for interruptions once you're really concentrating, because it will take you twenty minutes to recover.”

Matt Richtel explains in his article "Attached to Technology and Paying a Price" how multi-tasking can make us less productive than we think:

"Scientists say juggling e-mail, phone calls and other incoming information can change how people think and behave. They say our ability to focus is being undermined by bursts of information.

These play to a primitive impulse to respond to immediate opportunities and threats. The stimulation provokes excitement — a dopamine squirt — that researchers say can be addictive. In its absence, people feel bored.

The resulting distractions can have deadly consequences, as when cellphone-wielding drivers and train engineers cause wrecks. And for millions of people like Mr. Campbell, these urges can inflict nicks and cuts on creativity and deep thought, interrupting work and family life. While many people say multitasking makes them more productive, research shows otherwise.
Heavy multitaskers actually have more trouble focusing and shutting out irrelevant information, scientists say, and they experience more stress."