19 Interesting Facts
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Phone numbers are 7 digits because 7 is the brain’s 'magic number' for remembering items

Do you ever have a hard time remembering a list that contains more than a handful of items? Or…gasp…did you already forget that cute girl’s phone number because you didn’t write it down? Not to worry.

This isn’t a sign of early dementia, it’s your brain reacting to a very normal preset limit to it's remembering capabilities.

Much research has concluded that seven is the “magic number” where your brain is concerned. You probably have no problem remembering a phone number (for a few seconds, anyway) or a grocery list that has fewer than seven items.

But, if you go above the magic number of seven, you’re in trouble because only up to seven items can be stored in your brain’s working memory consistently.

The working memory is where your brain stores information it needs to use quickly. Phone numbers, items on a to-do list, or even geometry formulas for next period’s test get stored there. (In terms of studying, that’s why it’s important for your brain to cement the knowledge into short or long-term memory so the information can be called much later.)

If you want to store more than the seven items, try clustering. For example, if you want to recall that familiar song from 1982, remember 867 (1 item) and 5309 (1 item) instead of 8-6-7-5-3-0-9 all separately.


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