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Quantum Collapse of Entangled Microtubules
François Roy

Abstract– It is almost inconceivable to think that the ordered
firing patterns in neurons are the result of mere chance. For
this reason, we propose that there is a higher order
organisation which dictates the function of neurons in the
brain. Recent evidence by Hameroff and Penrose [1] has
revealed that microtubules found throughout the cytoskeleton
are capable of information and memory processing. It is their
periodic structure that makes them particularly well-suited for
encoding information. Their ability to collapse a wavefunction (information) further reveals that microtubules may
support micro sites of consciousness, and may therefore;
provide the basement level of consciousness in the cognitive
hierarchy. Hence, the entire interaction of entangled
microtubules scattered throughout the brain may be
responsible for initiating the cascade of reactions leading to
the organized firing patterns in neurons. As a consequence, we
further propose that quantum mechanics, along side systems
biology, can be used to describe the biological interactions
within the network of microtubules throughout the brain.
Index Terms–Microtubules, quantum brain, entanglement,
information processing, wave-function collapse
I. INTRODUCTION
We propose that biology is entangled in a web of wavefunctions and information. Just as chemistry can be used to
describe interactions of enzymes and substrates, or membrane
channels and ligands, we put forward that quantum mechanics
can be used to explain biological interactions at the molecular
level. Although these biological interactions are clearly not
related through Aristotle’s idea of direct causality (stating that
if A→B and B→C, then A→C), these interactions still exist
through the phenomenon of entanglement.
At the given time, we can think of entanglement as an
interaction between elements that have at some time interacted
with each other. We can treat entanglement as a dynamic
relationship between different components of a system.
Although these relationships are often not clearly defined in
terms of direct causality, it is nonetheless important to keep
their relationships in mind. For example, we can think of
entanglement as the relationship between a boy and his dog. In
this case, the boy’s future actions and interactions with other
dogs, for example, are influenced by this relationship. I for one
have never been particularly fond of dogs, but perhaps this is a
Manuscript received October 21st, 2003. François Roy is with the
Rehabilitation Engineering Laboratory of the Institute of Biomaterials and
Biomedical Engineering at the University of Toronto, Toronto, ON,
CANADA (email: [email protected])
consequence of my past experience as a young child when I
was attacked by one. In essence, my current thoughts of dogs
are the result of the entanglement of feelings of discontent and
fear in the presence of dogs. Albeit this example may seem a
little trivial at this time, the connection to system dynamics
will become clearer as the central argument is developed.
We will now delve into scientific research. Recent
developments initially made by Hameroff and Penrose [1],
have revealed that microtubules (MT) too are entangled with
each other. In biological terms, microtubules are sub cellular
protein polymers found throughout the cytoskeleton which
participate in a wide variety of dynamic cellular processes.
More importantly, microtubules are responsible for cellular
architecture and modulate many dynamic functions throughout
the cell. Of special interest is that microtubules have been
found to participate in bioinformation processing such as
learning and memory [2]. In fact, both microtubules along with
DNA are unique cellular structures that exhibit a robust code
system which dictates the function of processes throughout a
cell [3]. Just as the arrangement of nucleotide bases on DNA
forms the very basis for RNA transcription, and hence, protein
synthesis throughout a cell, the periodic structure of
microtubules makes them particularly well-suited to support
the encoding of information [2].
More particularly, microtubules can be used for the
superposition of coherent quantum states [3]. What this means
is that microtubules can be used to extract information from
many different signals, called wave-functions. For example,
we can think of a MT as some type of measuring device
similar to a measuring ruler. When a stick, in this case the
wave-function, is presented to the microtubule, the
microtubule measures and records the length of the stick, say 1
meter. Hence, the microtubule can support and extract
information from the wave-function of the stick, and collapse
the stick into its appropriate quantum state, length. The
superposition of quantum states means that other properties of
the stick can be measured and extracted at the same time. For
example, we can measure the length, the diameter and
circumference of the stick and superimpose the results
simultaneously. However, if we try to use microtubules to
support the quantum state of water, for example, then the
microtubule would be a little perplexed at trying to measure
the length of water. Of course, in a strict sense, length is really
not a property of water! Hence, microtubules are not able to
support this quantum state for water, and therefore will not
encode any information. This analogy is of course the very
basis which determines what information can be encoded.
What is interesting about information and memory in
microtubules is that the microtubules’ code system is strongly
related to a “mental code” or quantum computing [3]. When a
BME1450 – BIOENGINEERING SCIENCE (2003)
state of an object, for example, the length of the stick, is
recorded, the wave-function of the stick is collapsed into its
quantum state, length, and yields a particular value of 1 meter.
Hence, the value of 1 meter can be encoded and retrieved by
the microtubules through the collapse of the wave-function.
Moreover, at the moment of collapse, an organised quantum
exocytosis occurs. i.e. the simultaneous emission of
neurotransmitter molecules at the synaptic junction in neurons
[4]. When the superposition of quantum states occurs, more
states (or quantum states) related to the initial signal are
collapsed and further enhance the probability of release of
neurotransmitters at the synaptic junction. Importantly,
according to Norwich [5], the increase in the firing rate of
neurons is described as an increase in information transfer. As
a consequence, this may be how a “mental order” may be
translated into a physical reality through means of
physiological action. This is certainly convenient, since Hebb
[6] also found that an increase in the activity at the synaptic
junction in neurons is responsible for improved neural
communication and the emergence of learning in cells.
We will now introduce the idea of non-locality to this
framework. Non-locality refers to the idea of entanglement;
which again was the simple analogy of the boy and his dog.
Here, the idea of non-locality refers to the spatial relationship
or better yet, the entangled relationship of different objects in
space.
At this time, we will use a more concrete example to
describe the ideas of non-locality and entanglement. The idea
of non-locality, debated by Einstein, Podolski, and Rosen
(EPR-Paradox) [7] can be described using two chess-pieces.
Suppose we were to place a black chess-piece in one hand and
a white chess-piece in the other. With both hands behind our
back, what if we were to ask someone to try to guess which
hand holds the black piece. Of course, we can infer that the
information in each hand is entangled with each other. Since
we know that if someone picks the black piece in the right
hand, we will be certain that the left hand contains the white
piece. Now suppose that each piece was hidden again in our
hands, and each of the hands was taken to different ends of the
Universe. Could we still say that the chess-pieces are
entangled? Of course we can, since we still don’t know where
the black or white pieces are located. Therefore, the states are
still completely entangled, and as a consequence, non-locality
emerges. Einstein found it very disturbing to consider that a
measurement of one of the entangled states in one location had
an instantaneous effect on the other distant state. However,
experiments in the 1980’s have confirmed that the non-local
property of quantum mechanics exists [8].
Once again, non-locality refers to the presence of entangled
states even in completely distant localities. This of course
forms the very basis of this argument. As a wave-function is
simultaneously collapsed by multiple microtubules, the
information content of the signal is encoded by the entangled
states of the microtubules, and hence, information can be
encoded non-locally by the microtubules. Since wavefunctions interpreted by our senses can be collapsed by
microtubules in many cells throughout the brain, we propose
that information can be encoded and decoded by means of this
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enormous biological network or system of microtubules.
Moreover, the interaction of entangled microtubules dictates
and governs the subsequent biological cascades in an
organism, and hence, the firing patterns in neurons throughout
the brain.
II. FINDINGS
A. Microtubule: structure and function
The dynamic rearrangements of cytoplasmic structures,
including the cytoskeleton, account for the changing shape,
interaction, and motility of various cells [9]. The cytoskeleton
composed of microtubules, actin filaments, and intermediate
filaments are of fundamental importance for cellular function
and survival. Parallel-arrayed microtubules are interconnected
by cross-bridging proteins called microtubule-associated
proteins (MAPs) [3]. Importantly, the MT-MAP complexes
are responsible for regulating many dynamic functions of cells
including mitosis, cell differentiation, and synaptic formation
and function. It is usually understood that microtubules are
ubiquitous throughout all of cellular biology [10]. Importantly,
as DNA is the genetic library for hereditary information,
microtubules are the real-time executives of the dynamic
activities within living cells [3].
Fig. 1. (A) Structure of a microtubule. The tubulin dimers arranged
throughout the the microtubule are comprised of α and β monomers [1]. (B)
Model of the two state configurations of the tubulin protein. The states|α>
(left) and |β> (right) are determined by the position of the electron on the
tubulin subunit [1].
Microtubules are hollow crystalline cylindrical structures
whose walls are made up of hexagonal lattices of tubulin
dimers (Fig.1). Moreover, microtubules self-assemble to
extend the axons and dendrites at synaptic connections of
neurons [11]. Of importance, each tubulin dimer found on the
microtubules can exist in one of two different geometrical
conformations |α> or |β> (Fig. 2), [12]. Each of the |α>
and |β> configurations corresponds to a different state of the
dimer’s electric polarization. This occurs since an electron
placed at the α-tubulin/β-tubulin junction may shift between
the two different positions. This of course embodies the
textbook case of a two-state quantum-mechanical system.
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More careful study of the microtubules’ structure by Koruga
[2] has revealed that microtubules possess a coding system.
Importantly, it was found that microtubules possess the best
known binary error-correcting codes called the 6-binary-dimer
K1[13,26,5] [13]. It was also found that the conformations of
the two microtubule states or code systems are strongly linked
to protein function [3]. Theoretical models further suggest that
conformational states of tubulin within microtubule lattices
may interact with the six neighbouring tubulins to process,
represent, and propagate information throughout the cells [14].
This mechanism has often been called a molecular computing
system.
B. Entanglement in single-celled organisms
We can infer that the phenomenon of quantum entanglement
of microtubules started thousands of years ago when
prokaryotic cells became entangled through spirochetes,
prokaryotes possessing a whip-like tail composed of
microtubules [15]. Today, single-celled eukaryotic organism,
like the amoeba and the paramecium appear to have adaptive
or almost cognitive abilities; amoeba can search for food
whereas paramecium can avoid obstacles [3]. If these singlecelled organisms completely lack a nervous system, then how
can these adaptive or so-called cognitive abilities be possible?
A logical explanation is that microtubules provide
communication and information processing through the cell.
According to experiments by Sherrington [16] almost half a
century ago, the cytoskeleton is used for coordinated action in
the form of metachronal waves, vibrations in the cytoskeleton.
This can clearly be seen through movement or beating of the
cilia (tail-like structure). Coincidently, this corresponds to a
signal transduction in sensory cilia due to the propagation of
changes in the conformations of microtubules [17].
C. Experiments on microtubules
Many other experiments have revealed that microtubules are
related to so-called cognitive function or information
processing in the brain. Experiments with trained goldfish
have revealed that the drug colchicine produces retrograde
amnesia, by interfering with microtubules at the synaptic
junctions [18]. Other experiments on baby chick brains have
revealed that peak information processing through memory,
learning, and experience occurs simultaneously with high
levels of tubulin production and, hence, microtubule activity
[19]. Similarly, baby rats have also shown a significant
increase in tubulin production in the visual cortex when they
first opened their eyes [20]. Furthermore, experiments on
humans with neurological disorders including Alzheimer’s
disease and schizophrenia have also revealed impaired
functions in the microtubules and their associated proteins
[21]. Together, these experiments are good indicators that
microtubules are important in information processing in the
brain.
D. Effect of Anaesthesia on microtubules
There also seems to be a connection between coherent
oscillations in the microtubule conformational states and the
emergence of consciousness [1]. It is a well-known
phenomenon that the EEG of patients under general
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anaesthesia persists despite that absence of consciousness.
Nonetheless, it is rather remarkable that general anaesthesia
can be induced by a number of different substances from
chloroform to ether to xenon [22]. Studies on the mechanisms
of anaesthetics have revealed that they act on the
conformational functions of proteins, thereby blocking the
changing states of microtubules from occurring [23]. The
anaesthetic molecules disrupt the Val der Waals’ forces and
prevent the normal configuration switching of tubulin from
occurring. Furthermore, as the concentration of anaesthetics is
decreased, the temporal Van der Waals forces blocking the
electron flow between the tubulin proteins are removed, and
the conformational changes within the microtubules are free to
occur. This simple explanation of the puzzling features of
anaesthetics further provides evidence that microtubules are
perhaps micro sites of consciousness [24]. There is of course a
cognitive hierarchy, and microtubules may provide the
basement level of consciousness.
III. DISCUSSION
We have proposed that the wave-functions interpreted by
the senses can be collapsed by non-local microtubules. The
collapse of the wave-functions in the entangled states of the
microtubules forms a so-called system of perceived
information.
By looking at the ElectroEncephaloGram (EEG), we would
certainly expect that the asynchronous firing of multiple
randomly distributed neurons would produce a zero net effect
on the scalp electrodes. Instead, it has been found that the
evoked potentials from the firing of particular non-local neural
groups are radically different from the results from
spontaneous random cortical activity [25]. This is certainly
quite interesting, since it seems that the temporal
rearrangement within neural groups can characterize the
evoked potentials. Amazingly enough, by imposing the phase
characteristics of the invoked potential on the spontaneous
waveform, it is possible to reproduce the characteristic shape
of the observed waveform i.e. regenerate the initial wavefunction [26]. As a consequence, it seems that the external
stimulus, interpreted by the senses, does not only add energy to
the brain, but yet it organises the signal in a coherent way.
Hence, it provides a coherent superposition of the quantum
states of the signal. This is certainly similar to the case of the
stick in which we were able to superimpose the quantum states
of length, radius, and circumference simultaneously.
MRI scans can localize the spontaneous firing of distant
neurons through the brain. It is intriguing to note that distant,
nonadjacent regions of the brain can be activated during
different types of thoughts. It is almost inconceivable to think
of this as a result of pure chance, since our thoughts clearly
make sense to us. For this reason, we propose that
entanglement of microtubules during the collapse of wavefunctions forms the very basis of conscious thought. Indeed,
conscious thought seems to correspond to temporal states in
the brain with particular patterns of neural excitations.
Conscious thoughts are integrated by the collapse of quantum
states, described by the entangled microtubule networks. This
of course is quite important since it would reveal that non-
BME1450 – BIOENGINEERING SCIENCE (2003)
local neural groups are in fact related and interact with each
other. Hence, the firing pattern may be the result of the
entangled states of the microtubules in the different neurons
throughout the brain.
It is, however, the entire interaction of the entangled
microtubules which may activate neuronal synapses and
initiate the cascade of reactions leading to consciousness [3].
The hierarchical structure is susceptible to quantum treatment,
since it can be used to describe the particular dynamics of
microtubule interactions. We may consider the two
conformation states |α> and |β> of the tubulin dimers in the
microtubules as the basic unit for this quantum biological
system. Perhaps, we can even consider the entire brain as a
single measuring device where all the cells and neurons are
intrinsically related and constantly interacting through their
entangled states. The collapse of a wave-function transmitted
through the senses into an observable quantity, for example,
the length of the stick, allows us to consciously “feel” that the
stick has a length of 1 meter.
It is an organized series of fluctuations in the conformations
of microtubules which dictate our conscious thoughts.
Microtubules provide the database or the storage of
information from our senses, whereas quantum mechanical
principles extract the information into an observable whole.
The selection process for conscious thought is still completely
unknown; nonetheless, we propose that the entangled states of
the microtubules are the very mechanisms responsible for
bookkeeping and storing information.
IV. PROBLEMS AND ISSUES
We must keep in mind that the physical evidence supporting
the quantum collapse in entangled microtubules may
sometimes look circumstantial. In theoretical applications, the
hydrogen atom or even the electron in a vacuum is as far as we
have been able to push the understanding of quantum
mechanics. As a consequence, the explanation of quantum
collapse in microtubules is a great leap from an isolated
simplistic system to a completely in vivo process. Nonetheless,
the manner in which evidence from completely disconnected
fields fits together in such a coherent fashion may be more
than simply mere chance.
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understand how cellular processes occur and how elements of
biology are related. Here, we propose that cellular
components, more precisely microtubules, are intrinsically
connected with each other through the presence of
entanglement. In this case, we can assume that their dynamic
relationships are beyond any classical or Newtonian dynamics.
Nonetheless, this is a realistic assumption since cellular
processes occur at the molecular level, and therefore, as these
classical or Newtonian mechanics breakdown, tools at the
atomic and subatomic levels must be introduced. Their
relationships, as we have described, are certainly not as clearly
defined as in more standard systems biology approaches.
Nevertheless, they are equally and fundamentally important for
understanding how biology truly works.
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V. CONCLUSION
We propose that wave-functions interpreted by the senses
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brain. Information or memory intrinsically links microtubules
with each other through the process of entanglement. The
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Systems biology is itself a framework for understanding and
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