Conjectures on Consciousness F. Eugene Yates M.D. Scientific Advisor

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Conjectures on
Consciousness
F. Eugene Yates M.D.
Scientific Advisor
The John Douglas French Alzheimer’s
Foundation
February 26, 2010
The Phenomenon of
Emergence
Does it make technical sense to say that:
The mind emerges from the brain
and
Consciousness emerges from the mind?
NO!
Three Kinds of Emergence
1. A material thing “emerging” from a
material thing ( Bénard cells –not yet fully
analyzed!)
2. An immaterial quality associated with a
material thing (qualia , e.g., the perceived
color RED)
3. An immaterial illusion emerging from
another immaterial illusion (conscious
awareness “emerging” from a mind state)
A Criterion for Consciousness
Animals - with brains having highly
connected networks allowing a large
repertoire of goal-directed behaviors
under their normal conditions. (i.e., A
minimal complexity threshold is reached .)
No Invertebrates pass. (Social bees and ants
use non-conscious, limited – repertoire
instincts. Instincts ≠ consciousness.)
Norelco
Reporter
(cover)
Vol 27
Dec. 1980
Photo by Jack
Leonard
Three tests for “advanced” consciousness
1. Mirror test: patch on head (self- recognition
in mirror – human babies, elephants, chimps,
dolphins, magpies)
2. Tools and use of abstract symbols
( humans, some other primates, dolphins, a
few birds)
3. Following a pointer (i.e., Reading another’s
mind – human babies and domestic dogs!)
Who is conscious and when did it
appear?
All mammals (Terrestrial consciousness
first appeared here 200 million years ago)
with increasing complexity → Primates:
chimpanzees, gorillas (60 mya), Hominids
(7 mya), Hominins (Genus Homo 3 mya)
Some birds (parrots, corvids) (54 mya)
(feathered dinosaurs 150 mya –not conscious)
Trends in Brain Sizes
Hominids (10 to 7 mya)
• Ardipithecus ramidus (“Ardi”) 4.6 mya,
420 cc ( slightly larger than a chimp’s brain
then and now 400 cc)
• Australopithecus afarenses (“Lucy”) 3.2
mya, 450-550 cc (now ahead of chimp’s
brains – unchanged for last 6 million years)
Starting 2.5 mya, brain size slowly doubled
next million years: transition Au→H
Brain trends: Hominins ( 2.3 mya )
(Diet (?):brain size nearly doubles again!)
• Homo habilis 2.3 mya 800 cc (Tools!)
• H. erectus (Turkana Boy) 1.8 mya 900 cc
• H. heidelbergensis 0.5 mya years ago
(Common ancestor to Neanderthals and
us; controlled use of fire; brains ↑ ↑)
• H. neanderthalensis 0.25 mya
• 1400 cc (larger than ours!) No inbreeding
• H. sapiens 0.2 mya 1300 cc ( decrease!)
Power consumption
is ~ 20 Watts
It’s a
dim
bulb!
What drove the trend to bigger
Hominid/ Hominin brains?
Answer: (Diet and mutations → Bipedalism
- walking upright - not to see farther, but to
save calories. Upright walking is much
more energetically efficient than climbing
and swinging in trees, or knuckle-walking.
We are uniquely designed to RUN!! And, as
brains enlarged, so did the scope of
consciousness: migration ranges, tools,
ornaments, symbols, hearths, speech.
Who had speech?
Possibly all hominins since H. habilis (2.3 mya).
Definitely H. neanderthalensis as well as H.
sapiens - for the last 200,000 years.
All animals seem to have the FOXP2 gene necessary (but not sufficient) for speech. The
protein product of that gene in us, who have
speech, differs from that in chimps, who don’t,
by only two amino acids out of 740!
Mystery about Hominin Survivors
About 100,000 years ago- maybe just 50,000
five hominins were simultaneously alive:
Homo: habilis, erectus,heidelbergensis,
neanderthalensis and sapiens.
Question: Since 25,000 years ago, we are
the only survivors! WHY??
Answer: Because we have a special brain
supporting the widest range of diets and
adaptations to severe climate changes.
Varieties of the Special Human
Consciousness
• Awake and alert awareness of “now”
(Wm James “The specious present”.) It has
constancy of perception. (Hand-eye test).
• REM sleep dreaming (if “lucid” -“Avatars”)
• Daydreaming; reveries (default” brain
state, potentially creative)
NOTE: “States” in physics can be either static or
dynamic – (“states of motion…”)
Elements of Alert Consciousness
Alert consciousness has three components:
1. Awareness of “now” (sensory inputs from
body + environment→ RAS, pons, mesen.
tegmentum, subthal, hypothal, int
cap.→neocortex →consciousness)
2. Attention (focused awareness)
3. Memories
Two Essesntial Sources
• Christof Koch (with Francis Crick) (2004)
The Quest for Consciousness: a
Neurobiological Approach
(Outstanding documentation)
• Gerald Edelman (2004) Wider than the Sky:
the Phenomenal Gift of Consciousness
(Detailed ideas based on particular, recurrent
networks – especially thalamocortical with
re-entry.)
PROBLEM
Consciousness seems as mysterious
as ever.
Why?
Three “missing” perspectives?
1. A quantum physical model? (Caution!)
2. The arts? ( the qualia problem)
3. A compelling metaphor? (Metaphors are
powerfully evocative: e.g., Highwayman
poem.)
Metaphors and Science
When great scientists encounter the ineffable
they often resort to metaphor:
• Einstein: moving trains (relativity)
• Maxwell: vortices (magnetic fields)
• Eddington: expanding balloons (cosmos)
• Schrödinger: live- and-dead cat (QM states)
• Gamov: cosmic firecracker (Big Bang)
DESPERATELY SEEKING
CONSCIOUSNESS OUT OF QUANTUM
PHYSICS
Who has tried a QM approach?
SAMPLES
• Max Delbrück (1986) Mind from Matter
• Roger Penrose (1994) Shadows of the Mind
Rick Grush and Patricia Churchland have
written a superb criticism of Penrose and
QM approaches:
http://mind.ucsd.edu/papers/penrose/penrose
html/ penrose-text.html
• Giuseppe Vitiello (2001) My Double
Unveiled
► SymmetryThe dissipative quantum
model of brain
breaking→
ordering→
information
► QFT resolves
conflict between
reductionism and
holism!
2001
(Search in Classical QM, QFT or QED?)
Six Profound Quantum Physical Principles
Superposition of (quantum) states
Bohr Complementarity ( views not states)
----------------------------------------------Heisenberg Indeterminancy (uncertainty)
Correspondence (Bohr)
Quantum Coherence
Entanglement (strange entailments)
A Metaphor: The Omega “entailer”
Fact: Brain stateα ↔ Brain state β ↔ Brain stateγ
(Brain states in red are special.)
Brain states are material;mental states are not.
----------------------------------------------------------Hypothesis: Brain state β
Ω
Mental state β
Ω asserts the influence of a “quantum-like
conjugate” -a non-causal, immaterial
companion (an entailment).
What is Omega Ω?
An entailment, indicating a non-causal
association involving a complementary
pair (a “brain state” and a “mind state”)
that require a different descriptive language
for each. Both
are
there
together,
superimposed as if
quantum states.
Awareness occurs when the brain
measures itself. One set of neurons checks
on the state of another set, and in doing so
“collapses” the probabilities
of the
observed state to a perceived image.
First Consequence of Ω
• The immaterial mind becomes (in visual
metaphor) an “image” of a material brain
state – a very close “reflection” of the
ongoing processing of material neurons and
neural networks. It is a “picture” the brain
takes of itself.
• “Mind” has no actions of its own in the
material world. Visually, it is like your
reflection in a mirror - that doesn’t emerge
from you, can’t interact with you, or move
your material chair.
Second Consequence of Ω
There are no efficacious interactions
between “mind” and “brain” states!
The mind is an impotent image- in
visual terms a reflection - of an
efficacious brain state.
(All other senses, besides vision,
also have Ω entailments).
SUMMARY →
SUMMARY-1
• Only living animals can be conscious.
• Not all living animals are conscious some are “instinctive”.
• Goal-directed (teleonomic) behavior
is a common feature of both conscious
and instinctive behaviors.
SUMMARY- 2
Only mammals and a few birds have
known consciousness potential. (They
are all warm-blooded !)
Question:
Should
my
“consciousness detector”
body temperature”?
proposed
measure
SUMMARY 3
Everything that happens in mind or body
arises from dynamics of brain states.
All “interactions” are among brain states,
not between brain & “mind”.
SUMMARY 4
• As brains have evolved and enlarged,
so has the range of their possible states.
• Brain states with Ω- entailed mental
states have supported an increasingly
rich repertoire and content of behavior
and consciousness. A manifestation of
that richness is enhanced creativity.
SUMMARY 5
The big problem always has been to
describe mechanistically the
associations between objective
physical situations and our subjective
(conscious) experiences of them.
It can be done without invoking the
concepts of “emergence” or of
physical, mechanistic “causalities”.
Summary 6. (final)
Qualia, Arts, and the Limitations of
Normal Science
-------------------------------------------Newton and Galileo launched science on a
causal, mechanistic course that, even when
updated, utterly fails to account for our
conscious experience. It is too incomplete.
To illuminate consciousness we require the
arts. Science alone can’t do it. Example:
Proust’s joy from his madeleine and tea.
A Thoughtful Opinion
“It is quite possible – overwhelmingly
probable, one might guess – that we
will always learn more about human
life and personality from novels than
from scientific psychology.”
(Noam Chomsky)
Now, let the poet speak →
The Secret
We dance round in a ring and suppose,
But the Secret sits in the middle and
knows.
Robert Frost
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