With reference ot this ambiguous figure, I would like to clarify a further circumstance, which seems to be to be important in understanding the processes of consciousness. Even when several perspectives are possible, only one is ever realized at any given moment. We seethe cube either this way or that; we see the man or the mouse. We never see both perspective of the cube simultaneously, or a confusion of man-and-mouse, a “cognitive chimera.” This indicates that there is always only one object of consciousness. When this one thing occupies the center of attention, everything else including the other perspectives, withdraws into the background -- becomes the background. Implicitly, then, the single content of consciousness can persist only a few seconds, before giving way, to be replaced by another.

These ambiguous figures allow us an interesting insight into the dynamics of the processes of consciousness. A content of consciousness can apparently persist up to circa three seconds. If nothing new is presented requiring other events in the environment to be acknowledged, the alternative perspective thrusts itself automatically into the foreground of consciousness. If still nothing new occurs --if we are again, that is, not “diverted” -- then after a few seconds the first perspective returns to consciousness, and so on. After a few seconds, then, the capacity for integration is exhausted. The temporal frame for the given no longer suffices, and something new must assume its place in consciousness. 59/60