Reactivity

&

Reductionism

Descartes &

reductionism

Descartes introduced

reductionism

,

the study of the world as an assemblage of physical parts that can be broken apart and analyzed separately

.

[Edward O. Wilson.

Consilience. The unity of knowledge

. A.A. Knoff. New York. 1998, p. 29]

REDUCTIONISM

 Since the 17 th century, the mechanistic associated with Descartes has dominated

reductionist

European

and world view

American

thought about nature and society.

 According to this view, the world is made up of things.

separate objects

,  These things are essentially passive ; they normally remain the way they are but can be set in motion by

external causes

.

 They can be properties examined in

measured isolation

. The resulting most important things about them.

from each other and their

quantitative

differences are the  Finally, once we have measured and described them, we can combine them into structures that will behave according to the properties analyzed

in isolation

.

Richard C. Lewontin & Richard Levins

, 1988

Stimulus - Reaction

Stimulus



Reaction Today

 A fundamental issue in neurobiology is how sensory stimuli guide motor behavior  A major component of this problem involves understanding how the brain represents sensory features (p. 487) Ranulfo Romo & Emilio Salinas. Sensing and deciding

in the somatosensory system// Current

Opinion in Neurobilogy

1999

, 9: 487-493

Reductionism & Fun

While Occam’s razor is a useful tool in the physical sciences, it can be a very dangerous implement in biology

Francis Crick ( … a vigorous habitual reducer …)

It is, of cause, always

more fun reducing than being reduced

.

… Crick finds the over-simplicity of the physicists’ view of his own subject much more obvious than his own over simplicity in approaching the social sciences and humanities.

[Mary Midgley.

The ethical primate. Humans, Freedom and Morality

. London & New York. Routledge. 1994, pg. 38.]

THE FRAGMENT OF THE RATIONALE OF THE SYMPOSIUM “PERILS AND PROSPECTS OF TNE NEW BRAIN SCIENCES” (Stockholm, September 15 – 19, 2001) The dominant tendency amongst

neurobiologists

is severely

reductionist

, whilst by contrast amongst

psychologists

there remain strong

anti-reductionist

predilections.

Reductionism

The Scientific Belief

Our minds behavior brains – of – can the our be explained by the interactions of nerve cells (and other cells) and the molecules associated with them.

[

F. Crick

.

The Astonishing Hypothesis

. New York: Charles Scribner’s Sons. 1994, p.7]

A Scientific Theory of the Mind

By “scientific” … I mean a description based on the neuronal and phenotypic organization of an individual and formulated

solely

in terms of physical and chemical mechanisms giving rise to that organization. [

G.M. Edelman

.

The remembered Present.

New York: Basic Books. 1989, pp. 8-9]

THE CARTESIAN THEATER

Descartes held that

for an event to reach consciousness, it had to pass through a special gateway

… which Descartes located in the pineal gland or epiphysis. But everybody knows that Descartes was wrong

(?!-Yu.I.A.).

Not only is the pineal gland not the fax machine to the soul; it is not the Oval Office of the brain. It is not the “place where it all comes together” for consciousness…

I call this mythic place in the brain where it all comes together … the CARTESIAN THEATER

.

Dennett D.C. Brainchildren. Essays on Designing minds . Penguin Books: London, 1998, p.132

THE NEURAL BASIS OF ROMANTIC LOVE • Nothing is known about

the neural substrates involved in evoking

one of the most overwhelming of all affective states, that

of romantic love

.

• • The activity in the brains of

17 subjects who were deeply in love

was scanned using fMRI, while they viewed pictures of their partners.

• The activity was restricted to foci in the medial insula and the anterior cingulate coretx and, subcortically, in the caudate nucleus and the putamen.

A unique network of areas is responsible for evoking this affective state

.

Bartels A. & Zeki S. Neuroreport. 2000, 11 (17): 3829-34

Localization of Intelligence

A recent study by Duncan et al. [7] has found evidence that

general intelligence is localized to regions of the lateral prefrontal cortex

.

M. Atherton et al.

Cognitive Brain Research

, 16 (

2003

) 26-31, pg. 27

THE CONNECTIONS

EXISTING

BETWEEN THE LIMBIC SYSTEM

AND

THE PREFRONTAL CORTEX

OFFER A MATERIAL BASIS FOR

RELATIONSHIPS

BETWEEN

THE EMOTIONAL

AND

COGNITIVE

SPHERES [Changeux J.-P. & Dehaene S. Neuronal models of cognitive functions.

Cognition

, 1989, 33, 63-109]

C- and U-neurons

“I divide the nervous system into two types of

neurons, those concerned with consciousness, “C” neurons

, and

those which take care of unconscious functions, “U” neurons

(the use of the word “neuron” in this context is shorthand for “otherwise unspecified subpart of the brain”). The goal of

anesthesia is to interfere temporarily with the function of C neurons

the U neurons.” without disturbing [John C. Kulli.

Is Searle conscious?

BBS, 1990, 13:4, 614]

Left: microtubule, a cylindrical lattice of tubulin proteins. Right: coupled to position of a pair of quantum coupled electrons in an internal hydrophobic pocket, each tubulin may occupy two classical conformations (top) or exist in quantum superposition of both conformational states (bottom). A tubulin may thus act as a classical bit (top) or as a quantum bit, or ‘qubit ’ Microtubule simulation in which classical computing (step 1) leads to emergence of quantum coherent superposition and quantum computing (steps 2, 3) in certain (gray) tubulins. Step 3 (in coherence with other microtubule tublins) meets critical threshold related to quantum gravity for selfcollapse (Orch OR). A conscious event (Orch OR) occurs in the step 3 to 4 transition. Tubulin states in step 4 are noncomputably chosen in the collapse, and evolve by classical computing to regulate neural function. (b) Schematic graph of proposed quantum coherence (number of tubulins) emerging versus time in microtubules ( MTs). Area under curve connects superposed mass energy

E

with collapse time

T

in accordance with

E

=

h

−bar/

T

.

E

may be expressed as

N

t, the number of tubulins whose mass separation (and separation of underlying space time) for time

T

will selfcollapse. For

T

=25 ms (e.g. 40 Hz oscillations),

N

t=2×1010 tubulins.

Conduction pathways in microtubules, biological quantum computation, and consciousness S. Hameroff , A. Nip, M. Porter, J. Tuszynski Byosystems,2002,64,149-168

FROM PREPARATION TO THE BEHAVIOR



Predictions are fallacious

Many results regarding

...

physiology and pharmacology during anesthesia cannot be extrapolated to behavioral conditions

[West M.R. Anesthetics eliminate somatosensory-evoked discharges of neurons in the somatotopically organized sensorimotor striatum of the rat.

The Journal of Neuroscience

, 1998,18, 9055 9068]

Reductionism and fundamental understanding

Continued reductionism and atomization will probably

not

, on its own, lead to fundamental understanding

.

[Koch Ch. & Laurent G. Complexity And The Nervous System.

Science

,

1999

, 284, 96-98]

REDUCTIONISM &

• Western science took the lead

$

largely because cultivated

reductionism

. it • The most productive scientists , installed in million-dollar laboratories, have

no time to think about the big picture and see little profit in it

.

•

The eyes of most leading scientists, alas, are fixed on the

GOLG.

• It is therefore not surprising to find

know what a gene is

, and

physicists who do not biologists who guess that string theory has something to do with violins.

[

Edward O. Wilson

.

Consilience. The unity of knowledge

. A.A. Knoff. New York. 1998, pp. 31, 39]

PRO :

Development of Western

science

is based on two

great achievements

: the invention of the formal logical system (in Euclidean geometry) by the Greek philosophers, and the discovery of

the possibility to find out causal relationships by systematic experiment

(during the Renaissance).

Albert Einstein

CONTRA :

“The prime aim

of the physical

sciences

is not the discovery of causes or causes chains

...

Causes

[medicine, engineering, etc].” are the concern of

the applied sciences

Stephen Toulmin

Causes are the concern of the applied sciences

“The prime aim

of the physical

sciences is not the discovery of causes or causes chains

... The study of the causes of this or that event is … always an application of physics. It is, then, still in case where our interest is in

how one might … produce or counteract some spot-lighted development, that we talk about causes

. … From this we can see why

the term “cause” is at home in the … applied sciences, such as medicine and engineering

,

rather than in the physical sciences

. For

the theories of the physical sciences differ from those of the diagnostic and applied sciences

much

us maps differ from itineraries

. In the physical sciences … the regularities we find … are represented in a way which is

application-neutral

. …Simple chain like prescriptions can be given only in restricted sets of circumstances: we can confidently match causes and effects only in a given context . So

once we shift from the diagnostic to the physical sciences the idea of a causal chain is of as little use as the term “cause” itself

.

” Stephen Toulmin The philosophy of science. Hutchinson’s university library, Hutchinson House,

London. 1958