So there's a great phrase that we in cognitive neuroscience like to use, which is "chasing the homunculus". If you're not familiar with the term "homunculus", it literally means "little man", and it's used semi-pejoratively to refer to the notion you're talking about here. For example, neurologically (simplified, of course):

our behavior most obviously manifests by our actions
actions are motor responses
motor responses are made active by muscle contractions
muscle contractions are caused by neurons exciting muscle tissue
those neurons are excited by neurons in the spinal cord
the spinal cord receives input from the motor cortex
the motor cortex is excited by the premotor cortex
the premotor cortex translates intention to action
the premotor cortex receives input from various subregions of the prefrontal cortex (that may or mot be meaningful designations)
the prefrontal cortex is important for attention and decision-making

What is attending? What is making the decisions? We can keep chasing this all the way, but we're running out of a "top". Or, as my friend put as the title in his review in the journal Neuron, we're, "Searching for the 'top' in top-down control".

Personally, I don't think there's a "top". We're a complex feedback system of perception and action with updating and memory.

This isn't an excellent answer, maybe... but it's the best this neuroscientist can do. Please let me know if this makes sense.

Author's Bio: 

I have been working as a Growth Hacker for WPBeginner for an year now. This has always been my dream job, but I didn't get to this point overnight. I had to struggle for 9 years working for two other companies with which I wasn't happy working for. I had a lot stress and anxiety issues, in my blogs at SelfGrowth, I intend to share my experience and help them how to deal with workplace stress.