Critical phenomena arise at transitions when a system is at the edge of order and disorder, leading to interesting complex dynamics. Critical phenomena appears in many phenomena, from the evolution of the universe to the properties of superconductors and social interactions among humans. In physical systems, critical points occur when going through phase transitions, characterized by exotic emergent properties that have long intrigued scientists. Critical dynamics are best demonstrated in a simplified system known as the Ising model, with small changes in some critical environmental variable leading to drastic changes in the function. Self-organized criticality suggests that many natural systems fall into the category of tuning to critical points. Neuroscientists have investigated whether brains might exhibit self-organized criticality and if operating at the critical point could optimize information transmission. However, scientists have found it difficult to simulate true criticality in such a complex biological system with many variables interacting at once. The big question that remains is what the homeostatic mechanism is for tuning brains to the quasi-criticality region. Despite the hesitation to agree on a theoretical idea such as criticality, the hope is that there might be some general principles that explain how intelligence functions in the world we live in.
1. Critical phenomena arise at transitions.
2. Interesting complex dynamics can arise when a system is at the edge of order and disorder.
3. Critical phenomena appear in many phenomena such as the evolution of the universe, properties of superconductors, flocks of starlings, networks of brain cells, tectonic plates, and social interactions among humans.
4. Small changes in critical environmental variables lead to drastic changes in the function of critical systems.
5. Critical dynamics are best demonstrated in a simplified system known as the Ising model.
6. When a system reaches the critical point, it displays a telltale peak in what is known as the correlation length.
7. Networks of neurons would be optimized for information transmission when they hover near the critical point.
8. The big question that is unanswered so far is what is the homeostatic mechanism bringing back the brain to this quasi-criticality region.
9. Most neuroscientists are very hard-nosed empiricists who don't believe that there is an overarching theory that explains all of what the brain is doing in one handy concept.
10. The technological advance in neuroscience to record the individual spiking activity for many thousands of neurons is a precision tool needed to test new ideas on criticality.