In those split seconds when people witness others in distress, neural pathways in the brain support the drive to help through facets of imagination that allow people to see the episode as it unfolds and envision how to aid those in need, according to a team of Boston College researchers.
source https://www.lifetechnology.com/blogs/life-technology-news-blog/the-brains-pathways-to-imagination-may-hold-the-key-to-altruistic-behavior