This is what usually comes to mind when people think of yogis. Sitting quietly in a seated position for hours removing themselves from this world. In it, but not of it. This was something thought to be attainable by the few and has long since been understood as easily within grasp of all.
Withdrawal of the senses can be done 1 at a time or in any combination. Beginning this practice can sometimes lead to anxiety as our lives are filled with so much noise we don’t know what to do when it’s gone. This is why many fall asleep with the TV on, the radio in the background or in giant cities with millions of people making noises constantly around them.