Ever bought a new car and then seen the same make and model everywhere? But you never noticed it before?

That is your Reticular Activating System (RAS).

With over 2 billion pieces of data coming at you every second you need a filter to sort the information and only allows through what you need.

The RAS only allows through information that fulfils at least one of the following criteria:

Survival: The RAS notices things it perceives are imminent threats and makes you pay attention. Ever been woken up in the middle of your night because there was an odd (but not necessarily loud) sound?

Difference/Novelty: This ties directly into the first criteria, as things that stay the same often are not perceived a threat, but if something changes then it might…

Like when you get a new piece of clothing or new car, for a few weeks you really admire it, but after then the novelty starts to wear off and you no longer really pay that much attention.

Emotional content: This includes things you like and enjoy as well as friends and family members.

You might catch a snippet of a song you particularly like over the hum of a crowd, or see a friend on a crowded street.