Do people with dementia have a specific part of their mind actually formulating an intention to shut down memory and awareness? If so, can that part of their mind be targeted via subconscious channeling to do trauma resolution and encouragement?

This can be done and is akin to doing Parts Work in hypnotherapy. There is a quite deliberate decision-making part of the self that devises a strategy to escape. It is a willful and, in a sense, conscious part of the self in its deliberate decision making. Even though it is in a deep subconscious level of the mind where this takes place, it is very akin to having subparts of the being, each with their own set of beliefs to some extent, that differentiate their history and their current state of being and priorities as well as their agenda for living primarily with respect to survival, as that is the primary role of subconscious—to keep the self safe and be watching for harm in standing a vigil. So you can explore this for yourself by asking to speak with the part of the subconscious wanting most to escape from the threats that are mounting, and you will be able to zero in on that level of the subconscious most responsible for producing the symptoms of dementia. This will greatly speed progress as that part of the mind may or may not be on the surface when you go in to begin questioning the subconscious during a channeling session.