The focal conditions and dominating conditions that give rise to the six types of cognition -- namely, the cognitive objects and cognitive sensors of each of the six cognitive faculties. In the case of the five sensory faculties, the objects and sensors are forms of physical phenomena, such as sights and photosensitive cells. In the case of the mental faculty, the objects may be any validly knowable phenomenon, while the sensors are the immediately preceding moments of mental cognition. Usually counted as the twelve stimulators of cognition, but in the list of the twelve links of dependent arising, referred to as the six stimulators of cognition, in which case the two cognitive stimulators of each cognitive faculty are counted as one.
J. Hopkins: Sense-sphere,sphere.