When ambient conditions shift from an "uncomfortable" zone to a "neutral" zone, psychological responses move from "hot" to ’comfortably cool" or from "cold" to "comfortably warm." In those cases, each movement of the psychological responses reverses on the ASHRAE scale. A new model that can explain those phenomena without contradiction is proposed in this paper. And it is mentioned that the terms "hot," "uncomfortably warm," "comfortably warm," "uncomfortably cool," and so on, can be shown on a plane composed of two dimensions, the ambient index and the
physiological index.

Units: SI