According to current theory, our perceptions are the results of brain states, with the brain being some kind of computing device, with states or configurations within the computer mapping to different perceptions.
Let's start of with the belief that the brain is some kind of computer. Consider a brain whose cells are made of stars, stars banded into and connected by energy chains which amount to the neurons, axons, synapses and what-nots which make up a brain. If this star-formed brain is to match the biological brain it will have to be the size of a galaxy, so we will call it the Galaxy Sized Brain, GSB for short. Imagine that this Galaxy Sized Brain has energetic connections whose activations mimic those of a biological brain exactly. We assume that a conscious intelligence forms around this Galaxy Sized Brain, just as a conscious intelligence forms around a biological brain.
Consider a state within the biological brain that results in a scene arising in the consciousness, such as the present state in which the observer is reading a text such as this, even identical to this - "My Galactic Brain". The observer has the sense of being confined in a small body, probably in a room, looking at this text on their mobile device or laptop. Were that state to arise within the biological brain, would the same scene arise in the consciousness of the Galaxy Sized Brain? The same sense of being confined in small body, probably in a room, looking at this text on the mobile device or laptop?
In spite of the Galaxy Sized Brain being millions of light years in size, if a particular biological brain state results in the sense of the person being only 6 feet tall, having a 48 inch chest and a 40 inch waist, does the same state in a Galaxy Sized Brain result in the same perception in the observer? Within that Galaxy Sized Brain could ruminations arise of the possibility of it being a Galaxy Sized Brain, yet having the semblance of a biological brain, and within that biological brain, ruminate that it was actually a Galaxy Sized Brain, a Galaxy Sized Mind?
Would it possible for the consciousness of the Galaxy Sized Brain never to realize that it was formed from a Galaxy Sized Brain and consider itself to be formed from a biological brain right from its very conception to its death, when all interactions between the star clusters ceased?
PS. Consider the case of a brain whose states are computed out of band and assembled to create the images, with some parts of the computations being hived of to far flung nodes, some of them being handed to processing nodes in the future and being returned back in time for the images to be assembled. That would be interesting wouldn't it?