The neocortex of the brain tends to shut down (downshift) under threat, and survival mechanisms are activated. The concept of downshifting appears to fit with both what is now known about the triune nature of the human brain and what is observed in instructional settings and activities of daily living. The neocortex functions fully only when one feels secure. (Hart, Leslie A. Human Brain and Human Learning. NY: Longman Inc, 1983, pp 108-110)