If you are associating the 'I' as your body and mind you have just limited yourself to something finite and limited and rather chaotic!
Atma, translates as 'the Self is the truth'.
All else is false, unreal.
Therefore Atma kah is the reality beyond all falsehoods.
The moment you identify with something you drag the limitations of that something on your self.
To access the Atman, the Self within each of us we need to understand the nature of our false attachments to our thoughts, people and experiences.
To detach from these false attachments in order to gain the insight, simply begin to command the mind to return to your natural state of silence by choice when ever you choose.