Filtering The Mind

As a kid growing up I lived at the most 50 feet from the railroad tracks.

Trains came by my house all hours of the day and night at various speeds, some crawling to a stop, others actually reached 70 miles per hour.

This was normal to me, however when we had visitors they all would comment on the noise the trains created and wonder how we dealt with it.

Some of our visitors, who would spend the night, would complain that they awakened during the night fearing an earthquake only to realize the noise was from one of the trains passing in front of our house.

The next morning at breakfast they would say "We didn't sleep much because you had three trains come through last night and we don't know how you stand it," to which our response was "Three, really, we didn't hear any of them."

Now some 45 years after moving away, I just learned why the trains never bothered my sleep.

My wife is reading a book and she shared a passage she came across referring to the exact same thing about living next to the railroad tracks and sleeping through the noise.

What I learned is our brains possess a fascinating function known as the "Reticular Activating System."

It's a function through which our minds eliminate the thoughts and the impulses deemed unnecessary.

The reticular activating system in my mind processed the sounds of the trains going by and allowed me to sleep through it.

Another example of how the Reticular Activating System, or RAS, works:

Imagine that you're walking through a busy noisy airport passenger terminal. Think of all the noise - hundreds of people talking, music, announcements, luggage carriers.

How much of this noise is brought to your attention? Not a lot.

True, you can hear a general background noise, but not many of us bother to listen to each individual sound.

But then a new announcement comes over the public address system, saying your name or maybe your flight. Suddenly your attention is full on.

Your RAS is the automatic mechanism inside your brain that brings relevant information to your attention.

Your reticular activating system is like a filter between your conscious mind and your subconscious mind.

It takes instructions from your conscious mind and passes them on to your subconscious.

For example, the instruction might be, "listen out for anyone saying my name."

I always wondered why I could sleep through the deafening sounds of the trains rumbling through the silence of the night and now I know.