We propose that cerebral dynamics can be considered as a non-Hermitian quantum system which during a short interval of the cardiac cycle has real eigenvalues. We show that driving the system into PT symmetry is only possible with the help of the active matter changing from a laminar flow into a Ceilidh dance-like flow. During this change, the flow experiences  a transition from broken to unbroken PT symmetries which results in a topological phase. The topological phase is then imparted onto the topological defects which are an essential part of this Ceilidh dance flow. This so-called topological braid could be the basis of topological computing in the brain. Our recent experimental findings in conscious humans have shown that the predicted PT symmetry changes may exist. This is important because it is also related to consciousness underpinning  the computational aspect of the phenomenon. 

For many years, it has been speculated that consciousness and cognition could be based on quantum information  \cite{sep-qt-consciousness} which opposes the view that quantum coherence, the primary basis of quantum computing \cite{nielsen_chuang_2010}, cannot survive in complex biological systems \cite{Koch_2006,Tegmark_2000}. However, recent findings in photosynthesis \cite{Engel_2007,Collini_2010,Scholes_2017} have challenged this view suggesting that only long-range quantum coherence between molecules can account for its efficiency in light-harvesting. Here, we investigated if long-range quantum coherence may also play a decisive role in brain function. We found, surprisingly, that the cardiac pressure pulse evoked zero-quantum coherence (iZQC) \cite{Warren_1998} which were by a magnitude higher than theoretically expected. From this finding, we concluded that the underlying physiological process is - cautiously speaking - of an unknown macroscopic non-classical kind. The process reveals its importance by its temporal appearance; during consciousness it is highly synchronized with the cardiac pulse, while during sleep, no or only sporadic iZQC could be detected. These findings suggest that this non-classical phenomenon is most likely a necessity for consciousness.