 Most images can only be perceived in a single way. However, some images can be perceived in multiple ways, requiring the brain to choose from among the possible interpretations. This phenomenon is called by stable perception. Intuition would imply that the higher order regions of the brain, responsible for more traditional choices, would also be responsible for the perceptual decisions of by stable perception. But some evidence suggests that brain regions primarily involved in sensation may be in control. By combining a new kind of perceptually ambiguous stimulus with functional brain imaging, researchers recently showed that such higher order regions may actually not be required for this type of perceptual decision making. The researchers developed a by stable perceptual task in which human participants viewed sequences of moving dots while their brain activity was monitored using functional magnetic resonance imaging, or fMRI. Because the motion and position of the dots presented to each eye differed, the participants sometimes perceived the left eyes pattern of dot motion and sometimes the right eyes, but almost never a mixture of the two. Changes in neural activity caused these perceptual switches to occur. However, recognizing that such switches occur also changes neural activity. The problem is that the time scale of fMRI is too slow to distinguish the activity responsible for generating a switch from that related to recognizing the switch. The researchers therefore had to design the task so that perceptual switches would occur but would sometimes not be recognized by participants. The task had two conditions. One where the dots presented to each eye were different colors and one where the dot colors were the same. Participants easily recognized perceptual switches in the different color condition which meant that brain activity in this condition reflected both the cause and effect of switches. But they were much less likely to recognize switches in the same color condition demonstrating that this condition successfully minimized the effects of switches. Having established a way to isolate the brain activity related to the cause of perceptual switches, the researchers then evaluated the switch-related activity that occurred in three networks of higher-order brain regions thought to be involved in decision-making. They observed that the switch-related activity of these networks was much smaller in the same color condition indicating that these higher-order regions did not control perceptual switching. These results suggest that lower-order sensory areas of the brain rather than higher-order cognitive areas may be responsible for choosing what we perceive when we view ambiguous images. Future studies will need to more fully determine the role of higher-order brain regions in this process.