The over-stimulation of the modern world can create a detachment from the present moment, causing you to be sucked into the chaos. Positivity is a choice that can only happen if you create space between the input of stimulation and your reaction to it. Cultivating quiet in your life and your mind can create this space.
The brain is capable of on-going myelination (the official word for creating new neural pathways). It is possible to create new connections, and subsequent thoughts and experiences. Coaching is one of the ways to consciously create these new pathways, and therefore, literally change our minds.