Coherent Energy Transfer and the Potential Implications for
J. Tory Toole1,2, P. Kurian3,4, T. J. A. Craddock2,5
College of Psychology, Nova Southeastern University, Ft. Lauderdale,
FL 33328, USA1
Clinical Systems Biology Group, Institute for Neuro-Immune Medicine,
Nova Southeastern University, Fort Lauderdale, FL 33328, USA2
Department of Medicine, Howard University College of Medicine,
Washington, DC 20059, USA3
Quantum Biology Laboratory, Howard University, Washington, DC
Departments of Psychology & Neuroscience, Computer Science, and
Clinical Immunology, Nova Southeastern University, Fort Lauderdale,
FL 33314, USA5
The argument that biological systems are too “warm and wet” to support
quantum effects is becoming increasingly antiquated as research in the field
of quantum biology progresses. In fact, not only is it becoming apparent that
quantum processes may regularly take place in biological systems, but these
processes may underlie the mechanisms of consciousness and propel our
models of conceptualizing the human brain into the next era of scientific
understanding. The phenomena of consciousness have allured scientists and
philosophers for thousands of years, while a precise technical understanding
has remained elusive. If possible, developing this understanding will likely
be one of humanity’s greatest achievements. Knowing the fundamental
processes that create conscious experience has far-reaching implications,
from the potential birth of true artificial intelligence to a better
Journal of Cognitive Science 19-2:115-124, 2018
ⓒ2018 Institute for Cognitive Science, Seoul National University
116 J. Tory Toole, P. Kurian, T. J. A. Craddock
understanding of mental health disorder etiologies and treatments. One
major challenge in the mental health professions, and, ultimately, in
empathy of any kind, is being able to see from and appreciate another
person’s unique, subjective experience. Discoveries in the field of
consciousness could help bridge this gap.
Keywords: Consciousness; Coherent energy transfer; Quantum biology
Consciousness has proven to be one of the most elusive ideas for scientists
and philosophers to fully understand. The primary reason for this lack of
understanding lies in the tension between the personalized and subjective
nature of consciousness, on the one hand, and the scientific belief that
observable phenomena constitute an objective external reality, on the other.
We may, for example, be able to agree on the number of people in a room,
but it is quite another matter to assess how the people in a room make one
feel. While consciousness can be described as the subjective experience of
any one person, the fundamental limit to knowing another person’s unique
first-person experience creates a gap in truly understanding the phenomena
of consciousness. This seemingly unbridgeable gap between first-person
subjective “qualitative” experience and third-person “objective” reality has
placed conscious awareness just beyond the reach of traditional quantitative
scientific observation. While some believe consciousness and subjective
experiences (i.e. qualia) to be human constructs to describe a series of
mental processes with physiological correlates, others believe this concept
transcends our classical understanding of the inner workings of the brain,
with notions suggesting that qualia are physically real but beyond physical
observation (Beshkar, 2018). However, since the creation of the computer,
the brain has been reduced to a machine of inputs and outputs, effectively a
biological computer that follows the deterministic rules of classical physics.
Certain aspects of the brain, however, have challenged this concept, with
consciousness chief among them.
As such, in the early 1990s Sir Roger Penrose, a mathematical physicist,
Coherent Energy Transfer and the Potential Implications for Consciousness
made the conjecture that consciousness may be related to quantum
phenomena, just beyond the reach of our current understanding and models
of the brain (Penrose 1991). This work, furthered by collaboration with the
anesthesiologist Stuart Hameroff (Penrose, 1994; Hameroff & Penrose,
1996; 2014), suggested that quantum processing may occur in the network
of protein structures maintaining the architecture of brain cells, namely
within neuronal microtubules. This idea that consciousness occurs on a
quantum level, while commonly attributed to Penrose and Hameroff, is not
an isolated discovery, beginning in germinal form with the founders of
quantum mechanics (Bohr, Schrödinger, Wigner, etc.) and continuing in the
recent past with Satinover (2001), Woolf et al. (2009), Reimers (2009),
Vaziri and Plenio (2010), Lowenstein (2013), Craddock et al. (2014),
Al-Khalili and McFadden (2014), Fisher (2015), and Jedlicka (2009; 2017)
and others theorizing in one way or another that quantum processes have
something to do with the workings of the mind.
The double-slit experiment informs us that a conscious observer can alter
the outcome of a quantum measurement. But what does “quantum” have to
do with the brain? The unique conjecture of Penrose rests on the idea that
human understanding, subjective experience, and conscious awareness are
in and of themselves non-algorithmic, and therefore they require a
biological substrate capable of supporting non-algorithmic processes.
Quantum mechanics describes such a set of laws that govern nature on the
microscopic scale. Trivially, these laws determine the energy levels of
electrons, the properties of atoms, and the behavior of photons, among other
things, and in this sense they apply in a straightforward manner to all matter,
including the brain. But these quantum laws also predict more “exotic”
properties of matter, which are observed to stem from coherent quantum
states formed from entanglement (multiple particles that cannot be
described independently even at large distances), superposition (a single
particle simultaneously existing in multiple states), and tunneling (a particle
passing through a classically insurmountable barrier). These properties of
quantum systems are directly responsible for much of the digital
technological growth of the last century, and they have led to the harnessing
and use of electricity, the creation of the computer, and the development of
cell phones. However, these same non-trivial quantum phenomena afford a
118 J. Tory Toole, P. Kurian, T. J. A. Craddock
biological system like the brain a degree of non-deterministic (i.e.
The connection between large-scale and small-scale physics has been
another elusive quest for modern physicists, manifesting most notably in the
irreconcilability between general relativity and quantum mechanics. Strides
have been made to use quantum understanding to better human life in a
myriad of ways, from the light bulb and the early computer to quantum
processing, imaging, and cryptography. Biology, the study of life and its
dizzying array of complex systems, has traditionally been described by
physicists as large-scale and without quantum effects, with proponents
arguing that biological systems are too “warm, wet, and noisy” for quantum
processes to take place. This mainly stems from the difficulty in setting up
and maintaining a system in a stable quantum state, which often requires
near-complete isolation from the environment at extremely cold
temperatures (~-273℃) and shielded from stray electromagnetic fields.
Recent research, however, is suggesting that this is not the case. Quantum
coherent transport in photosynthesis, magnetoreception in birds, olfaction
(Lambert et al., 2013), and single-photon effects in vision (Fleming et al.,
2011) are just a few examples of how quantum effects in biology are
possible. For example, in 2007, quantum oscillations attributed to electronic
coherence were observed in the Fenna-Matthews-Olsen (FMO)
photosynthetic light-harvesting complex (LHC) at the relatively warm
temperature of -196℃, challenging the idea that quantum phenomena and
biology do not mix (Engel et al., 2007). This experiment was then conducted
at 4℃, nearing physiological temperature, and observed not only in the
FMO complex but in LHCs in plants (LHCII), bacteria (LH2), and
phycobiliproteins (Chenu et al., 2007; Hildner et al., 2015).
Many quantum biological systems currently known seem to be comprised
of a pigment (or small, non-protein molecule such as a ligand, odorant, or
flavin) in a protein environment (Brookes, 2017). The theoretical basis of
the coherent energy transfer in photosynthesis involves the unique
light-capturing nature of chlorophyll and the elegant geometrical
arrangement of these pigments in the LHCs of plants and bacteria. Due to
these characteristics, light energy can be efficiently captured and funneled
from the environment to reaction centers within the cell. This light
Coherent Energy Transfer and the Potential Implications for Consciousness
harvesting depends on the quantum mechanism through which
light-induced excitations hop between pigments (also known as
chromophores). The structure of chlorophyll molecules allows energy to be
transferred from an excited group of atoms to a neighboring group of atoms
via the resonance between their energy levels. This is analagous to the
phenomenon that occurs when striking a tuning fork and placing it near a
second tuning fork. The sound waves from the struck tuning fork resonate
with the second fork, causing it to vibrate as well. This phenomenon,
however, is not unique to photosynthesis, and is simply attributable to the
specific structure and arrangement of chromophores within a protein.
One potential site of interest for understanding how quantum processes
may occur in the human brain is the microtubule, a hollow cylindrical
polymer of the protein tubulin. These structures are among the most
abundant in the cytoskeleton of the cell and are responsible for maintaining
cell morphology, trafficking cell cargo, cell motility, and possibly playing a
role in signal transduction. They are essential to maintaining the complex
architecture and inner workings of brain cells. Tubulin, the microtubule
constituent protein, possesses a network of chromophoric tryptophan (Trp)
amino acids. These aromatic chromophores, with their specific structure
and arrangement in tubulin, may also support coherent quantum effects.
Craddock et al. (2014) investigated the biological feasibility of this type of
coherent energy transfer in tubulin and found that it is theoretically possible
for energy to be transferred via this quantum process. This suggests that the
structure of microtubules in the brain can feasibly use coherent energy
transfer, similar to photosynthesis, as a mechanism for signaling and
The spatial distribution and orientation of the Trp amino acids in tubulin
are shown to be comparable to that of chromophores found in other
light-harvesting biological systems (e.g., cryptophyte marine algae), which
have also been shown to support quantum-coherent transfer of electronic
excitation. As mentioned, spatial distribution and orientation of
chromophores are key hallmarks of this quantum process. Craddock et al.
(2014), using modeling and simulations, found that the electronic
characteristics and spatial orientation of Trps within microtubules are
comparable to light-harvesting structures in plants and bacteria, and that it
120 J. Tory Toole, P. Kurian, T. J. A. Craddock
is very feasible that the quantum processes experimentally observed to
occur in these plant/bacteria structures may take place within the Trp
network in tubulin. This is indeed noteworthy, as it suggests that not only
can quantum-coherent energy transfer occur in photosynthetic systems, but
it may happen more generally in eukaryotic cells, including cells in the
The possibility of coherent energy transfer occurring in the human brain
carries with it many exciting implications. For one, these underlying
quantum phenomena could be an important clue in better understanding the
mechanisms of neurodegenerative tauopathic disorders such as
Alzheimer’s disease and Parkinson’s disease-related dementia. These
specific types of disorders are characterized by altered forms of the
microtubule-associated protein (MAP) tau, which is a key protein in
stabilizing the microtubule architecture that regulates neuron morphology
and synaptic strength. It is this uniquely elegant architecture that gives rise
to the possibility of coherent energy transfer. MAP tau is a very important
protein in neuronal axons. It acts to stabilize the microtubule cytoskeleton
and, when compromised, allows the cytoskeleton to disintegrate. This type
of neurodegeneration is the hallmark of these tauopathic diseases.
Understanding the mechanisms by which the microtubule cytoskeleton
becomes destabilized may lead to new diagnostics and therapies for these
One prominent early event in tauopathy, or the pathological aggregation
of the MAP tau protein, is oxidative stress. In a biological context, reactive
oxygen species (ROS) are chemically reactive chemical species containing
oxygen. They are the natural byproduct of oxygen metabolism and play
important roles in the functioning of the cell (Wilson et al., 2015). While the
production of ROS is a natural part of aerobic life, a surplus can be
detrimental. Oxidative stress occurs when there is an imbalance between the
amount of ROS being naturally produced and the bo dy ’s ab il ity to d etoxify
the reactive intermediates or repair resulting damage. While these ROS
reactions can interact in a variety of ways throughout the body, certain
chemical processes result in excited-state molecules that release photons
(particles of light) of specific energies ranging from the ultraviolet through
the visible to the infrared (Cifra and Pospisil, 2014; Van Wijk, 2014; Mei,
Coherent Energy Transfer and the Potential Implications for Consciousness
1994; Slawinska and Slawinski, 1983). Exposure to light in the
near-ultraviolet range causes absorption by proteins, primarily mediated by
the aromatic amino acids tryptophan, tyrosine, and to a lesser extent
phenylalanine. Therefore, it is possible that as ROS reactions cause the
emission of photons in the cell, these photons are absorbed and transferred
through the microtubules via amino acids such as tryptophan. The degree
and extent of this process, and whether or not this absorption and emission
involves coherent energy transfer, however, remains an open question. Yet,
as we have discussed, this process appears to be theoretically possible and
achievable under biological conditions, meaning that energy transfer within
cells could occur, at least in part, through quantum coherence. Furthermore,
because ROS reactions can be a catalyst for this energy transfer, oxidative
stress can cause destabilizing effects in tubulin and the microtubules of the
cell due to disruptions of such coherent energy transfer.
In very recent work, Kurian et al. (2017) modeled the effects of
ROS-induced excitonic propagation via coherent energy transfer in
aromatic networks of linear tubulin polymers. They found that this process
is significant on at least the micron scale, suggesting the physiological
relevance of such coherent dynamics. This finding also alludes to the
possibility that such excitations resulting from metabolic activities may
influence neural firings, which are dictated by rates of ion flow through
sodium, potassium, and other channels via changes in the microtubule
cytoskeleton. This coherent energy transfer in any one instant may be
inconsequential behaviorally. However, coherent energy transfer across
multiple microtubules in a neuron and across many brain cells via
synchronous neuron firing may have implications in brain activity,
behavior, and even consciousness.
Yet, while this mechanism in and of itself is not tied to a specific theory
of consciousness, it is consistent with propositions made by others regarding
the quantum nature of conscious processes. In regards to the study of
subjective consciousness, if such a system is capable of generating
physically real but physically unobservable properties (Beshkar, 2018), or if
it can be considered as an indefinite causal structure (Hardy, 2009), this may
provide room for a physical description of unmeasureable (i.e. subjective)
qualia, and therefore consciousness. Just as the discovery of quantum
122 J. Tory Toole, P. Kurian, T. J. A. Craddock
mechanics was a paradigm shift for our understanding of matter, the
possibility of quantum biology not only occurring in the brain, but being
responsible for the manifestation of consciousness, could be a major
paradigm shift in the way we conceptualize the mind, the brain, psychiatric
disorders, and neurodegenerative diseases. Furthermore, understanding the
connections between the mechanisms of the brain and the underlying
quantum phenomena could lead to new questions and answers about the
connections between macroscale phenomena and quantum physics. As we
further our understanding of the various roles quantum processes can play in
human experience, we take steps towards a potentially more complete
understanding of consciousness.
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