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You've put your keys somewhere and now they appear to be nowhere, certainly not in the basket by the door they're supposed to go in and now you're 20 minutes late for work. Kitchen counter, night stand, book shelf, work bag: Wait, finally, there they are under the mail you brought in last night.

Losing things is irritating and yet we are a forgetful people. The average person misplaces up to nine items a day, and one-third of respondents in a poll said they spend an average of 15 minutes each day searching for items—cellphones, keys and paperwork top the list, according to an online survey of 3,000 people published in 2012 by a British insurance company.

Everyday forgetfulness isn't a sign of a more serious medical condition like Alzheimer's or dementia. And while it can worsen with age, minor memory lapses are the norm for all ages, researchers say.

Our genes are at least partially to blame, experts say. Stress, fatigue, and multitasking can exacerbate our propensity to make such errors. Such lapses can also be linked to more serious conditions like depression and attention-deficit hyperactivity disorders.

"It's the breakdown at the interface of attention and memory," says Daniel L. Schacter, a psychology professor at Harvard University and author of "The Seven Sins of Memory."

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