The sky due to it's subtle nature doesn't mix with the air and the sun doesn't get affected by the things that is illuminated by sunlight. Similarly the spirit soul is distinct from the body and senses even though its consciousness is spread all over the body. 

An intelligent person situated in transcendental knowledge can see that the soul actually does nothing while eating, sleeping, evacuating, moving about, but only the modes in action whereas a foolish person cannot feel his own soul distinct from his body and the type of enjoyment or suffering that he is experiencing with the modes of nature that he comes in contact.

Conscious beings get attached to their support and the supporters. But I am not attached to anything in the material world even though I am situated in everyone- Sri Krishna in Bhagavad Gita.