Whatever brings peace of mind is spiritual. Helping others, being ethical, finding purpose in life, all these are ways to develop one's spirituality. Just the opposite. Brain washing or the zombie state is one of complete loss of one's mental control. Someone else is controlling the mind.
Meditation frees the mind from stress and ideas that enslave it.
The mind has more clarity, awareness, and penetrative abilities. The student grows in peace and virtue. There are three main stages of samadhi. It is called Saibikalpa Samadhi. When the mind becomes habituated to this peacefulness it is then able to notice a still greater peace- the inner eternal peace.