One way to look at the brain is that it continually expresses the mind. Mind and brain are two sides of the same coin. From a subjective view perception, thought, intention, attention etc. is felt and experienced. At the same time a corresponding (set of) functional neural networks activate.
A state of mind, such as “move my hand left – now,” will have a corresponding brain signal. Similar states of mind, as they are repeated, form a state of mind “signature,” and corresponding brain signal signature.
A given brain signal signature reflects a type of mind expression (ex: the intention “move my hand left”). Mind/brain signatures are also “targets” in that the user tries to repeat — i.e. hit — them with each movement.
The content of the mind = perception, recognition, thought, goals, imagery, intention, attention, and the rest of one’s strongest and most powerful experience. More precisely, the mind is made of the activation of a set of memories, based on past experience (ex: “reach,” “my right hand,” “coffee cup,” “coffee,” “desire,” “take a sip” etc.).
Overall the mind = a set of (active) general memories = the set of (active) functional neural network ranges.
To the extent the user’s state of mind is accurately defined, her brain signal signatures – and targets for designer/tester/trainer/user to shoot for — will be better-defined as well.