Consciousness ... must issue from some physical mechanism which
is far more primitive than the developed human brain, from a
mechanism that is available to the lowliest amoeba.
...nearly half a century ago, biophysicists working on the retina
discovered that nerve cells in the human brain are sufficiently
sensitive to register the absorption of a single photon ... and thus
sensitive enough to be influenced by the whole panoply of odd
quantum-level behaviour, including indeterminism and non-local
effects.
There is ... an eerie similarity between the way both the brain
and the hologram distribute information across the whole system...
But even as a metaphor it goes too far in some respects, being as
extreme in its own emphasis on the wave-like side of being as
mechanism and the computer model are in their emphasis on the
particle side... A really adequate model of the nature of
consciousness and its relationship to the brain must be able to
account for both. ... the rock against which all previous theories
have broken, is the problem of unity of consciousness, the
distinctive indivisibility of our thoughts, perceptions, feelings,
etc.
The orderliness of awareness - its apparent stability within time
- is what gives us the feeling that we live in a world rather than
within experiences conjured up by capricious senses
Within our brains alone some ten thousand million neurones
contribute to the rich tapestry of our mental life. Another ten
thousand million or so cells keep our hearts beating, the same
number again give us a liver, and so on. How, given all this
complexity are we, in sum total, one thing?
Consciousness, by its very nature as a quantum system, is a
thread of freedom running through our lives at every moment... If we
reflect gently on the contents of our conscious minds, at any
moment, we are aware of a dim array of multiple thoughts, of
'possible thoughts'... Their reality is fuzzy, and their future
indeterminate, awaiting some act of realisation... In quantum terms
however, this fuzzy, indeterminate margin of thought is the
necessary precondition of all thought.
Everything you're consciously intending to do is preceded by neural
events of which you're not conscious. We walk through life thinking
we're the conscious author of our thoughts, but you can't think a
thought before you think it.
Active role of consciousness experiment
People volunteer to have electrical signals recorded at a point
on their heads (EEG's). They were asked to flex their right index
finger suddenly at various times entirely of their own choosing.
What is found is that there is a gradual build-up of recorded
electric potential for a full second, or perhaps even up to a second
and a half, before the finger is actually flexed. This seems to
indicate that the conscious decision process takes over a second in
order to act! This may be in contrasted with the much shorter time
that it takes to respond to an external signal.
Passive role of consciousness experiment
Patients undergoing brain surgery consented to having electrodes
placed at points in their somatosensory cortex. When a stimulus was
applied to the skin of these patients, it took about half a second
before they were consciously aware of that stimulus, though the
patients were not aware of the delay. Touching the corresponding
point in the cortex only revealed sensation if touched for more than
half a second. Now suppose that the skin is first touched, and then
the point in the somatosensory cortex is electrically stimulated
about a quarter second after the touching of the skin. The skin
touching will not be felt at all. This is backwards masking... The
conscious perception can be prevented by a later event, provided
that the event occurs within about half a second. This tells us that
the conscious awareness of such a sensation occurs at something like
half a second after the actual event producing that sensation. It
would appear that half a second must elapse before consciousness is
called in to play; and then well over a second before one's 'willed'
response can take effect. ... Perhaps consciousness is, after all,
merely a spectator who experiences nothing but an 'action replay' of
the whole drama.
Consciousness is, after all, the one phenomenon that we know of,
according to which time needs to flow at all! The way in which time
is treated in modern physics is not essentially different from the
way in which space is treated. Yet, according to our perceptions,
time does flow...
Bohm believes that consciousness is a more subtle form of matter,
and the basis for any relationship between the two lies not in our
own level of reality, but deep in the implicate order. Consciousness
is present in various degrees of enfoldment and unfoldment in all
matter, which is perhaps why plasmas possess some of the traits of
living things.
There's no theatre; there's no Cartesian theatre where everything
comes together for consciousness. There's this great competition
going on, all the time, between information, sensory information and
the different sense modalities, and lots of this is being put
together and analysed by what we might as well call for the moment
'sub-conscious' mechanisms, and it's all vying for influence in the
brain. And the stuff that succeeds in gaining and holding influence
for some time, long enough so that you can talk about it later,
that's what we're conscious of. It's only retrospectively that we
can identify what we were conscious of.
For billions of years there was no free will on this planet. Now
there is. What has changed is that evolution has created nervous
systems that have more and more power. And that access of power,
that capacity to look ahead, that capacity to reflect, that capacity
to respond to reasons, to give and respond to reasons, those
capacities are the core of moral responsibility. And we're the only
creatures that have them. And it evolved, and once it
evolved-ta-da!-we have entities that have tremendous power,
cognitive power, and that's what free will is. So it's sort of
noblesse oblige: Those of us who have the powers are obliged to use
them wisely.
See also consciousness
and awareness
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