There is No Empirical Data that proves reducibility
Both
sciences and the general public have come to accept the idea that the mind is
dependent upon the brain and that we can reduce mental activity to some
specific aspect of the brain upon which it is dependent and by which it is
produced. Within this assumption neuroimaging studies are given special
credence. These kinds of studies are given special credence probably because
the tangibility of their subject matter and the empirical data produced creates
the illusion of “proof.”[1]
Yet EEG and MRI both have resolution problems and can’t really pin point
exactly where neural activity is located.” In short, neuroimaging studies may
not be as objective as some would like to think. There are still large gaps
between observation and interpretation – gaps that are ‘filled’ by theoretical
or methodological assumptions.”[2]
Learning is not hard wired but is the result of “Plasticity.” This plasticity
is what allows us the flexibility to learn in new situations. This means that
most of our neocortex is involved in higher level psychological processes such
as learning from experiences.[3]
Our brains are developed by new experiences including skills acquisition.[4]
Exercise and mediation can change the brain.[5]
Classical
psychological reductionism assumes the mind is essentially the brain. Mental
behaviors are explained totally in terms of brain function. Mental states are
merely reduced to brain states.
But while it may be true that certain
psychological processes are contingent on some neurophysiological
activity, we cannot necessarily say that psychological processes reduce to
‘nothing but’ that activity. Why not? – Because much of the time we are not
dealing with cause and effect, as many neuroscientists seem to think, but
rather two different and non-equivalent kinds of description. One describes mechanism,
the other contains meaning. Understanding the physical mechanisms of a
clock, for example, tells us nothing about the culturally constructed
meaning of time. In a similar vein, understanding the physiological
mechanisms underlying the human blink, tells us nothing about the
meaning inherent in a human wink (Gergen, 2010). Human meaning
often transcends its underlying mechanisms. But how does it do this?[6]
Reducing mind to brain confuses mechanism with meaning.[7]
Raymond
Tallis was a professor of Geriatric medicine at University
of Manchester, and researcher, who
retired in 2006 to devote himself to philosophy and writing. Tallis denounces
what he calls “neurohype,” “the claims
made on behalf of neuroscience in areas outside those in which it has any kind
of explanatory power….”[8]
The fundamental assumption is that
we are our brains and this, I will argue presently, is not true. But this is
not the only reason why neuroscience does not tell us what human beings
“really” are: it does not even tell us how the brain works, how bits of the
brain work, or (even if you accept the dubious assumption that human living
could be parcelled up into a number of discrete functions) which bit of the
brain is responsible for which function. The rationale for thinking of the kind
– “This bit of the brain houses that bit of us...” – is mind-numbingly
simplistic.[9]
Specifically Tallis has refernce to experiments where the
brain is scanned while the subject does some activity and the differences are
attributed to some structure in that part of the brain. Tallis is highly
skeptical of this method.
Why is this fallacious? First, when it
is stated that a particular part of the brain lights up in response to a
particular stimulus, this is not the whole story. Much more of the brain is
already active or lit up; all that can be observed is the additional activity
associated with the stimulus. Minor changes noted diffusely are also
overlooked. Secondly, the additional activity can be identified only by a
process of averaging the results of subtractions after the stimulus has been
given repeatedly: variations in the response to successive stimuli are ironed
out. Finally, and most importantly, the experiments look at the response to
very simple stimuli – for example, a picture of the face of a loved one
compared with that of the face of one who is not loved. But, as I have pointed
out elsewhere (for the benefit of Martians), romantic love is not like a
response to a stimulus. It is not even a single enduring state, like being
cold. It encompasses many things, including not feeling in love at that moment;
hunger, indifference, delight; wanting to be kind, wanting to impress; worrying
over the logistics of meetings; lust, awe, surprise; imagining conversations,
events; speculating what the loved one is doing when one is not there; and so
on. (The most sophisticated neural imaging, by the way, cannot even distinguish
between physical pain and the pain of social rejection: they seem to “light up”
the same areas!)[10]
Hal Pashler’s study, University of California, San Diego is
discussed in an an editorial in New Scientist, he is quoted as
saying “In most of the studies that
linked brain regions to feelings including social rejection, neuroticism and
jealousy, researchers … used a method that inflates the strength of the link
between a brain region and the emotion of behaviour.”[11]
While no empirical data proves reducibility, some empirical data seems to support irreducibility. The mind cannot be reduced to the brain alone.
Some empirical data supports claim:
Irreducibility
There are,
however, empirical data that imply that brain is not necessary to mind. One
such datum is the humble amoeba. They swim; they find food they learn, they multiply,
all without brains or brain cell connections.[12] Various theories are proposed but none really
answer the issue. Stuart Mameroff (anesthetist from University
of Arizona) and Roger Penrose,
Mathematician form Cambridge, raise
the theory that small protein structures called microtubules found in cells
throughout the body. The problem is they don’t cause any problem with
consciousness when damaged.[13]
Nevertheless, the amoeba is a mystery in terms of how it works with no brain
cells. That leads to the recognition of a larger issue the irreducealbity
raises the question of consciousness as a basic property of nature. Like
electromagnetism, there was a time when scientists tried to explain that in
terms of other known phenomena, when they could not do so they concluded that
it was a basic property and opened up a branch of science and the
electromagnetic spectrum.[14]
David Chalmers and others have suggested the same solution for consciousness.
The late Sir John Eccles, a
neuroscientist who won the Nobel Prize for medicine in 1963 for his work on
brain cell connections (synapses) and was considered by many to be one of the
greatest neuroscientists of the twentieth century, was perhaps the most
distinguished scientist who argued in favor of such a separation between mind,
consciousness and the brain. He argued that the unity of conscious experience
was provided by the mind and not by the machinery of the brain. His view was
that the mind itself played an active role in selecting and integrating brain
cell activity and molded it into a unified whole. He considered it a mistake to
think that the brain did everything and that conscious experiences were simply
a reflection of brain activities, which he described as a common philosophical
view:
'If that were so, our conscious selves would be no more than passive spectators of the performances carried out by the neuronal machinery of the brain. Our beliefs that we can really make decisions and that we have some control over our actions would be nothing but illusions.[15]
'If that were so, our conscious selves would be no more than passive spectators of the performances carried out by the neuronal machinery of the brain. Our beliefs that we can really make decisions and that we have some control over our actions would be nothing but illusions.[15]
Top Down Causation
confirming irreducibility
Or downward
causation, as seen in last chapter: “Top-down causation refers to the effects
on components of organized systems that cannot be fully analyzed in terms of
component-level behavior but instead requires reference to the higher-level
system itself.” [16]
*problem of binding
There is a
problem with understanding what it is that binds together the unity of a
conscious experience. We have many different kinds of conscious faculty at work
in the process of being conscious, symbolic thinking, literal thinking, sense
of temporal, sense of reality, and physical perceptions. Somehow it all gets
brought together into one coherent sense of perceptions. How are the individual
aspects, such as color, form, the temporal, and united into a coherent whole
experience? Unification of experience is not achieved anatomically. There is
“no privileged places of structures in the brain where everything comes
together…either for the visual system by itself or for sensory system as a
whole ” [17]
McDougall took it as something that physicalilsm can’t explain.[18]
Dennett and Kinsbourne recognize the phenomena marking top down causation and
acknowledge it, they spin it as undermining unity.[19]
The old approach was to assume there must be an anatomical center for binding.
Without finding one the assumption was that it couldn’t be explained. Modern
explanations of unity are based upon a functional approach.
The essential concept common to all of
them is that oscillatory electrical activity in widely
distributed neural populations can be rapidly and reversibly synchronized in
the gamma band of frequencies (roughly 30-70 Hz) thereby providing a possible
mechanism for binding.” (von der Malsburg 1995). A great deal of sophisticated
experimental and theoretical work over the past 20 years demonstrates that
mechanisms do exist in the nervous system and they work in relation to the
normal perceptual synthesis. Indeed Searl’s doctrine of biological naturalism
has now crystallized neurophysiologically in the form of a family of global
workspace theories, all of which make the central claim that conscious
experience occurs specifically and only with large scale patters of gamma band
oscillatory activity linking widely separated areas of the brain. [20]
In other words if consciousness was reducible to brain
chemistry there should be an anatomical center in the brain that works to
produce the binding effect. Yet the evidence indicates that binding mechanisms
must be understood as functions of various areas outside either the brain
(nervous system) or in different parts of the brain which means
it can’t be reduced to just a physical apparatus but is systemic and that is
indicative of top down causation.
* Projective activity in perceptual process
Our
brains act as a sort of “word generating virtual reality system.”[21]
That is the brain is constantly projecting and updating a model of the
perceptual environment and our relation to it. Top down cross modal sensory
interactions have been recognized as the rule rather than the exception, in
perceptions, as several studies indicate (A.K. Engle et al, 2001; Shimojo and
Shams 2001). [22] Evidence indicates
that the ultimate source of projective activity may originate outside the
brain. A great deal of knowledge is put into action for use in understanding
language and in writing. Some researchers have advanced the view that the
fundamental form of projective activity is dreaming.[23]
*Semantic or intentional content; word meaning and other
form of representation.
This has been dealt with traditionally through reductionism.
Representations were said to work by resembling things they represent. This was
disproved by Goodman and Heil (1981). [24]
In cognitive psychology there is a rule of thumb that meanings are not to be
conceived as intrinsic to words, they are defined by the functional role they
play in a sentence. The major approach
to the problem used now is connectionism, from dynamic systems theory. The
meaning of a given response such as settling of a network into one of its
attracters or firing of a volley of spikes by a neuron in the visual cortex is
identified with the aspect in the environment that produces the response. This
account can’t deal with abstract things or non existent things. There’s nothing
in the environment to trigger it. Responses do not qualify as representations
nor signs as symbols. “That something,” as Searl so effectively argued (in
1992) “is precisely what matters.”[25]
*problem of Intentionality
Intentionality
is the ability of representational forms to be about things, to reflect meaning
and to be about events and states of affairs in the world. [26] The problem of intentionality has plagued
both psychologists and philosophers. Intentionality is inherently three ways,
involving the user, symbols, and things symbolized. Searl tells us that
intentionality of langue is secondary and derives from the intrinsic
intentionality of the mind. “Intentionality can’t be obtained from any kind of
physical system including brains.”[27]
*The Humunculus Problem
The
Homunculus was a medieval concept about human reproduction. The male was said
to have in him little men just like him with all the basic stuff that makes him
work that’s how new men get born. In this topic it’s the idea that we need in
the mind another mind or brain like structure to make the mind work. The
problem is it keeps requiring ever more little structures to make each one
before it work; in endless regression of systems. Kelly and Kelly et al site
Dennett’s attempt to solve the homunculus problem in the form of less and less
smart homunculi until the bottom level corresponding to heard ware level end
the recursion so it’s not infinite. (Dennett 1978)[28]
Searl (1992) responds that there has to be something outside the bottom level
that knows what lower level compositions mean. Cognitive models can’t function
without a homunculus because they lack minds, as Kelly tells us.[29]
No homunculus problem, however, is posed by the structure of our conscious experience itself. The efforts of Dennett and others to claim that there is such a problem, and to use that to ridicule any residue of dualism, rely upon the deeply flawed metaphor of the Cartesian theater a place where mental contents get displayed and I pop in separately to view them. Descartes himself, James, Searl and others all have this right: conscious experience comes to us whole and undivided, with the qualitative feels, phenomenological content, unity, and subjective point of view all built in, intrinsic features. I and my experience cannot be separated in this way. [30]
[1] Brad Peters, Modern
Psychologist, “the Mind Does not Reduce to the Brain.” On line resource, blog, 2/4/12
URL: http://modernpsychologist.ca/the-mind-does-not-reduce-to-the-brain/ visited 5/3/12
Brad Peters, M.Sc. Psychologist (Cand. Reg.) • Halifax,
Nova Scotia, Canada
[2] Ibid.
[3] ibid
[4]Schore, A. N. Affect
regulation and the origin of the self: The neurobiology of emotional
development. Hillsdale, NJ:
Lawrence Erlbaum Associates.
(1994).
See also: Siegel,
D. J. The developing mind: How relationships and the brain interact to
shape who we are. New York, NY:
Guilford Press. (1999).
[5] Peters, op cit.
[6] ibid.
[7] K. Gergen, The
accultured brain. Theory & Psychology, 20(6), (2010). 795-816.
[8] Raymond Tallis New
Haumanist.org.uk Ideas for Godless People (blog—online researche) volume 124
Issue 6 (Nov/Dec 2009) URL: http://newhumanist.org.uk/2172/neurotrash visited 5/9/12
[9] ibid
[10] ibid
[11] quoted by Tallis,
ibid.
[12] Science Research
Foundation, “Science at the horizon of life,” independent charitable
organization in UK 2007-2012. On-line resource, UFL: http://www.horizonresearch.org/main_page.php?cat_id=200 visisted 5/2/12
[13] ibid
[14] ibid
[15] ibid
[16] Mary Anne Meyers, “Top
Down Causation, an Integrating Theme…” Templeton Foundation Symposium, Op cit.
(no page number listed).
[17] Edward F. Kelley and
Emily Williams Kelley, et al, Irreducible Mind: Toward a Psychology for the
21st Century. Boulder, New
York, Toronto:
Rowman and Littlefield Publishing Inc, 2007/2010, 37.
[18] Ibid. 38, referring to
W.McDougall, Proceedings of scientific physical research 25, 11-29.
(1911/1961)..
[19] ibid. 38 refers to
Dennette and kinsbourne in Consciousness Explained. (op cit) 183-247
[20] ibid, sites C.Von der
Malsburg, “Binding In Models of Perception and Brain Function.” Current Opinion
in Neurobiology, 5, 520-526. also sited Crick 94; Dehaene and Naccache, 2001; Edelmon and Tononi, 2000; Engle, Fries
and Singer 2001; W.J. Freeman 2000, and others.
Engle, Fries, Singer cited in Pub Med: See comment in PubMed Commons below
Engle, Fries, Singer cited in Pub Med: See comment in PubMed Commons below
Nat Rev Neurosci. 2001 Oct;2(10):704-16.
Abstract
Classical theories of sensory processing view the brain as a passive, stimulus-driven device. By contrast, more recent approaches emphasize the constructive nature of perception, viewing it as an active and highly selective process. Indeed, there is ample evidence that the processing of stimuli is controlled by top-down influences that strongly shape the intrinsic dynamics of thalamocortical networks and constantly create predictions about forthcoming sensory events. We discuss recent experiments indicating that such predictions might be embodied in the temporal structure of both stimulus-evoked and ongoing activity, and that synchronous oscillations are particularly important in this process. Coherence among subthreshold membrane potential fluctuations could be exploited to express selective functional relationships during states of expectancy or attention, and these dynamic patterns could allow the grouping and selection of distributed neuronal responses for further processing.
[21] ibid
[22] ibid, 40, he sites
A.K. Engle et al, 2001; Shimojo and Shams 2001;
[23] ibid, 41-42 sites Rodolfo Llina’s and Pare’ 1996
Llina’s and Ribary, 1994.
[24] Ibid, 42 see Heil 1981
[25] ibid, 43 see Searl 1992
[26] ibid
[27] ibid, see also studies,
puccetti 1989; Dupuy 2000 discussion of issue form opposing points of view).
[28] Ibid see Dennett 1978
and Searl 1992)
[29] ibid
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