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Henry Stapp 2
Mind, Matter and Quantum Mechanics
Henry Stapp - Springer Verlag
Stapp
starts by asking what sort of brain action corresponds to a conscious thought. He
criticises the mainstream for assuming that Newtonian physics can be applied
directly to the brain, and claims that a quantum framework is needed to
understand the brain. The Copenhagen interpretation of quantum theory was the
first mainstream version, and was pragmatic in recommending the theory as a
system of rules that allowed the calculation of empirically verifiable
relationships between observations. Stapp favours Heisenberg’s refinement of
the original Copenhagen
position. Heisenberg thought that the probability distribution of quantum
theory really existed in nature, and that the evolution of this probability was
punctuated by uncontrolled events, which are the events that actually occur in
nature, and which at the same time eliminate the other probabilities.
The
development of computing during the second half of the 20th century
demonstrated that thought-like or cognitive processes required internal
representations not allowed for in the then prevailing behaviourist concept.
However, this still did not account for conscious experience, and in this
period thinking or cognition came to be seen as something separate from
consciousness.
Both Bohr and Heisenberg viewed quantum theory as a set of
rules for making predictions about observations under experimental conditions.
These predictions are incompatible with classical physics in respect of the
prediction of non-locality. Heisenberg did not view the quanta as actual things,
but as tendencies for certain types of events to occur. The orderly evolution
of the system is deterministic, but this controls only the tendencies for
things or propensity for events, and not the actual things or events
themselves. The things are controlled by quantum jumps that do not individually
conform to any natural law, but collectively conform to statistical rules.
Stapp
bases his proposal for quantum consciousness on three observations. 1.) The
brain’s representation of the body or body schema must be represented by some
form of physical structure in the brain. 2.) Some brain processes such as the
behaviour of calcium ions involved in synaptic transmission need to be treated
quantum mechanically. Stapp also thinks that the sensitivity and non-linearity
of the synaptic system, the involvement of calcium ions and the large number of
metastable states into which the brain could evolve all point to a quantum
mechanical system. 3.) Stapp suggests that the brain could evolve into a state
analogous to the deterministic evolution of the quantum state from which an
actual state must be selected.
Although Stapp pays a lot of attention to the
synapses his is not actually a neuron based theory. Rather the event could be
selected from the large scale excitation of the brain. The selection of events
from a wide range of probabilities is seen as being particular adaptive where
an organism needs to select from a range of future probabilities. Stapp
wishes to establish the relationship between mind and matter, the relationship
between reality and quantum theory, and also how relativity is reconciled with
both experience and non-locality. The solution is suggested to be a series of
creative events bringing into being one of a range of possibilities created by
prior events. He suggests that consciousness exercises top-level control over
neural excitations in the brain. The neural excitations are regarded as a code,
and each human experience is regarded as a selection from this code. He sees
the physical world as a structure of tendencies in the world of the mind. He
finds it as unacceptable that there is an irreducible element of chance in
nature as described by quantum theory, which is the most usual conclusion to be
drawn from the randomness of the wave function collapse. The element of
conscious choice is seen as removing chance from nature. He distinguishes
between systems where an external representation and knowledge of the laws of
physics can accurately predict how the system develops, and his own idea of a system
that is internally determined in a way that cannot be represented outside the
system.
The brain is viewed as a self-programming computer with
self-sustaining neural patterns as the codes. It is necessary to integrate the
code from sensory input, with the code from previous experience. This creates a
number of probabilities, from which consciousness has to select. The conscious
act is the selection of a piece of top-level code, which then exercises control
over the flow of neural excitation. The unity of conscious thought comes from a
unifying force in the conscious act itself. It selects a single code from
amongst a multitude on offer in the brain. Raising an arm involves a conscious
act selecting the top-level code that raises the arm. This is suggested to
close the traditional explanatory gap between thought and classical physics,
because here the conscious thought is the selection of the code that allows the
physical act. P. Stapp goes on to discuss the conscious process of looking at pictures.
According to him top-level codes instruct lower-level codes to produce new top
level codes and to initiate their storage in memory. The experience of noticing
something is deemed to be the process of initiation into memory. There are
close connections between the top-level code and the memory structure. The
lower level codes have to be functioning correctly i.e. not damaged, and to be
focused on the incoming stimuli in order for it to be put into higher level
code and to be registered in memory.
Stapp discusses what neural research
would need to reveal if it were to support his theory. It would need to reveal
the neural connections needed to support self-sustaining patterns of neural
excitation. It is necessary to find the neurons providing the top level coding,
then the mechanism for storing memory traces of this, and finally the mechanism
by which these memories are involved in the production of new top-level codes. P.
Each conscious experience is seen as a creative act represented in the physical
world by the selection of a top level code from among the many generated by the
laws of quantum theory. The conscious experiences are the initiation of
processes that produce changes in the body schema and the external and internal
reality schema. The conscious act is functionally equivalent to changes in the
physical world as represented in quantum theory. In the Heisenberg version of
quantum theory physical things are events and quantum theory gives the
propensity for particular events to occur. This is seen as providing a link
between conscious processes and brain processes. In the Heisenberg version it
is the act of observation which leads to the selection of a particular
propensity.
Stapp attaches great importance to the idea of the formation of
a record. This is seen as analogous to the Geiger counter that registers a
record of a quantum event. Every conscious experience is seen as recordable,
because it is evidence of some form of brain process. The later retrievability
of the experience is evidence of a record in the brain. A key process in brain
dynamics is seen as persisting patterns of neural excitation producing physical
changes in neurons that enable a particular pattern to be re-excited, and allow
re-excited pattern to connect with new stimuli. This is seen as the basis of
the brain’s associative memory.
The top-level brain process is viewed as a
process of actualising symbols, composed of earlier symbols connected into a
whole by neural links. The top-level process is seen as directing information
gathering, planning and choice of particular plans, monitoring the execution of
plans. This can be understood in terms of top-level direction of multiple
neural processes. Because of the top-level directive role, its connection to
associative memory and the multiple structure of the symbols involved it is
suggested that each top-level event corresponds to a psychological event, and
this in turn connects psychological events to the quantum level. Both the top-level
brain event and the psychological event act as choosers of a possibility, or
converters of potentialities into actualities. Each human conscious
experience is seen as the feel of an event in the top-level of processing in
the human brain, a sequence of Heisenberg actual events, actualising a
quasi-stable pattern of neural activity. Activation of particular symbols
creates a tendency for the activation of other related symbols. The body schema
is the product of actualised events accumulated over the life of the body. The
top-level symbols have compositional structure formed from other symbols. The
Heisenberg events are seen as being capable of grasping a whole a pattern of
activity, and this is seen as accounting for the unity of consciousness. The
continuity or flow of time is explained by an overlap of symbols with the preceding
mental event.
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