What is a Focus of Mind?
A functional part of the mind focussing on a major aspect of human life that promotes behaviour supporting evolutionary benefit.
Notes
A focus of mind supports behaviour and/or particular types of thinking that, when combined together with other focuses, provide evolutionary benefits of specific behaviour balanced by adaptive behaviour.
The HI Mind Model describes four main semi-conscious focuses:

A focus to promote basic family behaviour.

A focus to promote creativity and imagination, including play for social-learning and exploration for personal advantage.

A focus to promote language and hence enable large-group activities beyond the family/tribe.

A focus to promote appreciation of the significance of life beyond self-interest.
Our core consciousness can also be considered as a focus of mind with the function of managing the four main focuses.
The HI Mind Model defines these focuses through consideration of evolutionary selection but a loose mapping of these focuses to the brain can be inferred from the basic observed characteristics of the left and right brain hemispheres. However, it is not safe to assume that there is a direct relationship between particular activity in the brain and any of the focuses of mind.
Each focus of mind has particular qualities, such as speed of action and focus of interest, and characteristics including compulsions, emotions, imperatives, type of intellect.