Consciousness operates beyond the timescale for discerning time intervals: implications for Q-mind theories and analysis of quantum decoherence in brain

This paper presents in details how the subjective time is constructed by the brain cortex via reading packets of information called "time labels", produced by the right basal ganglia that act as brain timekeeper. Psychophysiological experiments have measured the subjective "time quanta" to be 40 ms and show that consciousness operates beyond that scale - an important result having profound implications for the Q-mind theory. Although in most current mainstream biophysics research on cognitive processes, the brain is modelled as a neural network obeying classical physics, Penrose (1989, 1997) and others have argued that quantum mechanics may play an essential role, and that successful brain simulations can only be performed with a quantum computer. Tegmark (2000) showed that make-or-break issue for the quantum models of mind is whether the relevant degrees of freedom of the brain can be sufficiently isolated to retain their quantum coherence and tried to settle the issue with detailed calculations of the relevant decoherence rates. He concluded that the mind is classical rather than quantum system, however his reasoning is based on biological inconsistency. Here we present detailed exposition of molecular neurobiology and define the dynamical timescale of cognitive processes linked to consciousness to be 10-15 ps showing that macroscopic quantum coherent phenomena in brain are not ruled out, and even may provide insight in understanding life, information and consciousness

Revisiting the microtubule based quantum models of mind: tubulin bound GTP cannot pump microtubule coherence or provide energy for alpha <-> beta computation in stable microtubules

The current paper investigates the biological models of stable brain microtubules as quantum or classical computers whose function is based on electron hopping associated with kinking of the tubulin dimer. Hameroff (1998a, 1998b, 2003a, 2003b), Tuszynski et al. (1998), Hagan et al. (2000), Mershin et al. (1999); Mershin (2003) suppose that the energy needed could be somehow delivered via guanosine diphosphate (GDP) exchange for guanosine triphosphate (GTP) or via cycles of tubulin bound GTP hydrolysis. Here is presented biological and structural data from electron diffraction studies performed by Lowe et al. (2001) and computer simulation with MDL ® Chime Version 2.6 SP4, explaining and visualizing the inconsistency of the proposed tubulin bit (qubit) GTP energized alpha <-> beta computation and/or tubulin bound GTP pumped coherence in stable microtubules

Solving the binding problem: cellular adhesive molecules and their control of the cortical quantum entangled network

Quantum entanglement is shown to be the only acceptable physical solution to the binding problem. The biological basis of interneuronal entanglement is described in the frames of the beta-neurexin-neuroligin model developed by Georgiev (2002) and is proposed novel mechanism for control of the neurons that are temporarily entangled to produce every single conscious moment experienced as present. The model provides psychiatrists with ‘deeper’ understanding of the functioning of the psyche in normal and pathologic conditions

Remarks on the number of tubulin dimers per neuron and implications for Hameroff-Penrose Orch OR

Stuart Hameroff has wrongly estimated that a typical brain neuron has 10^7^ tubulin dimers and wrongly attributed this result to Yu and Baas, J. Neurosci. 1994; 14: 2818-2829. In this letter we show that Hameroff&#x2019;s estimate is based on misunderstanding of the results provided by Yu and Baas, who actually measured the total microtubule length in a single axonal projection with length of 56 &#x3bc;m in a differentiating in vitro stage 3 embryonic hippocampal neuron. In order to visualize how big Hameroff&#x2019;s error is, we have reconstructed two of the studied by Yu and Baas embryonic hippocampal neurons with Neuromantic v1.6.3 and compared them with previously published reconstructions of adult hippocampal neurons. Correct calculations show that an adult differentiated pyramidal neuron in vivo has approximately 1.3&#xd7;10^9^ tubulin dimers incorporated in cytoskeletal microtubules. This estimate has profound implications for the Hameroff-Penrose Orch OR model, because it sets limitations on the number of quantum coherent neurons and implies that if 100% of the neuronal microtubules are quantum coherent for 25 ms then Hameroff-Penrose Orch OR conscious events should involve only 15 pyramidal neurons

Inner privacy of conscious experiences and quantum information

The human mind is constituted by inner, subjective, private, first-person conscious experiences that cannot be measured with physical devices or observed from an external, objective, public, third-person perspective. The qualitative, phenomenal nature of conscious experiences also cannot be communicated to others in the form of a message composed of classical bits of information. Because in a classical world everything physical is observable and communicable, it is a daunting task to explain how an empirically unobservable, incommunicable consciousness could have any physical substrates such as neurons composed of biochemical molecules, water, and electrolytes. The challenges encountered by classical physics are exemplified by a number of thought experiments including the inverted qualia argument, the private language argument, the beetle in the box argument and the knowledge argument. These thought experiments, however, do not imply that our consciousness is nonphysical and our introspective conscious testimonies are untrustworthy. The principles of classical physics have been superseded by modern quantum physics, which contains two fundamentally different kinds of physical objects: unobservable quantum state vectors, which define what physically exists, and quantum operators (observables), which define what can physically be observed. Identifying consciousness with the unobservable quantum information contained by quantum physical brain states allows for application of quantum information theorems to resolve possible paradoxes created by the inner privacy of conscious experiences, and explains how the observable brain is constructed by accessible bits of classical information that are bound by Holevo's theorem and extracted from the physically existing quantum brain upon measurement with physical devices

Conformational Dynamics and Thermal Cones of C-terminal Tubulin Tails in Neuronal Microtubules

In this paper we present a model for estimation of the C-terminal tubulin tail (CTT) dynamics in cytoskeletal microtubules of nerve cells. We show that the screened Coulomb interaction between a target CTT and the negatively charged microtubule surface as well as its immediate CTT neighbours results in confinement of the CTT motion\ud within a restricted volume referred to as a thermal cone. Within the thermal cone the CTT motion is driven by the thermal fluctuations, while outside the thermal cone the CTT interaction energy with its environment is above the thermal energy solely due to repulsion from the negatively charged microtubule surface. Computations were performed for different CTT geometries and we have found that the CTT conformation with lowest energy is perpendicular to the microtubule surface. Since the coupling between a target CTT with its neighbour CTTs is 8 orders of magnitude below the thermal energy and considering the extremely short cytosolic Debye length of 0.79 nm, our results rule out generation\ud and propagation of CTT conformational waves along the protofilament as a result of local CTT perturbations. The results as presented support a model in which the cytosolic electric fields and ionic currents generated by the neuronal excitations are "projected" onto the CTTs of underlying microtubules thus affecting their regulatory function\ud upon kinesin motion and MAP attachment/detachment

A linkage of mind and brain: Sir John Eccles and modern dualistic interactionism

Our minds, constituted by conscious experiences, are both the most familiar and most mysterious aspect of our lives. Despite the large amount of clinical evidence suggesting an intimate relationship between the brain function and the mind, the nature of this relationship remains poorly understood. In this Commentary we discuss some of the problems faced by the classical mind-brain identity theory and explain how the quantum dualistic interactionism proposed by Sir John Eccles could resolve these problems.Biomedical Reviews 2011; 22: 81-84