As I understand it, consciousness-causes-collapse (CCC) theories, although not very popular among physicists, have not been falsified (e.g. https://arxiv.org/abs/1609.00614).
This confuses me because my understanding of wavefunction collapse is that, at least some of the time, it must happen without a conscious observer present. The quantum Zeno effect, for instance, involves frequently "measuring" a radioactive element and thus preventing it from decaying. Each of the "measurements" in a quantum Zeno experiment are done by the measurement device (pulses of UV light).
While it is the case that no observer will become aware of these measurements until someone is conscious of them, it is still the case that a whole succession of collapses have occurred between conscious observations. This succession of collapses have had a measureable effect on the time evolution of the radioactive element, and the system would look different depending on whether they occurred or not.
My question is then: how do you maintain CCC theories on light of this? Doesn't this mean a single conscious measurement must be able to collapse a whole chain of multiple dependent collapse events far into the past? Or can it still be maintained as a single collapse at the moment of "measurement"? Or am I completely off base?