For hours, its sensory system had been tracking the strange sound above.

The sensory system is the way animals find out about their nearby environment.

A huge amount of data comes in from the sensory system.

But there is no reason why both these and other sensory systems should not be employed.

"These sensory systems operate all the time, without our being aware of them."

Your brain won't be able to tell that they're not coming in via the sensory system.

But why get involved with the primary sensory system at all?

Vision is an important sensory system for most species of fish.

In fact, the human body has seven sensory systems - not five.

Many of the brain's sensory systems may well be like this.