Quantum cognition - Matthew Fisher

Putative quantum processing with nuclear spins in the wet environment of the brain would seemingly require fulfillment of many unrealizable conditions: for example, a common biological element with a long nuclear-spin coherence time to serve as a qubit, a mechanism for transporting this qubit throughout the brain, a molecular scale quantum memory for storing the qubits, a mechanism for quantum entangling multiple qubits, a chemical reaction that induces quantum measurements on the qubits which dictates subsequent neuron firing rates, among others. My strategy, guided by these requirements, is one of reverse engineering seeking to identify the bio-chemical substrate and mechanisms hosting such putative quantum processing. Remarkably, a specific neural qubit and a unique collection of ions, molecules, enzymes and neurotransmitters is identified, illuminating an apparently single path towards nuclear spin quantum processing in the brain.