Friday, April 25, 2014

Neurodynamics and consciousness workshop 2-30 pm May 2 2014 Beach room 3rd floor Tolman Hall UC Berkeley

Neurodynamics and consciousness workshop
2-30 pm May 2 2014 Beach room 3rd floor Tolman Hall UC Berkeley

This workshop will have 2 parts; Walter Freeman will speak about the large and medium-scale (macro and mesoscopic) issues related to neural dynamics; Sean O Nuallain will speak about the microscale, individual neurons.

To familiarize attendees with the language used, an introduction to Walter's work is appended and papers summarizing the two approaches attached

Again, please note that this list in NOT the hotel California; you can check out AND leave FOM anytime, or simply mark this as spam and your server will do the rest

Introduction to Walter’s work

Over the past half-century, the Freeman laboratory has accumulated a
large volume of data and a correspondingly extensive interpretive
framework centered around an alternative perspective on  brain
function, that of dynamical systems. The contents of consciousness, by
contrast, are seen as an inevitably sparse sample of events in the
perception-action cycle. The paper proceeds to an attempt to elucidate
the contents of this sparse  sample.

 Freeman (2005a ) established  that local dynamics in rabbit and human
neocortex are scale-free, and that every skilled action involves all
cortex and basal ganglia in varying degree. Self-similarity from the
microscopic to the macroscopic levels of the cortex allows the cortex
to change state very quickly. Freeman (2002)  introduces the notion of
a wave packet, amplitude modulation of which constitutes the
expression of knowledge, which is stored in synaptic modifications and
expressed by phase  transitions.  Freeman (op.cit., 517) also makes
the radical contention that we do not need independent access to the
external world for communication to occur; it is sufficient that the
internal meanings in speaker and hearer  come transiently into

The felt experience of consciousness is constrained by the fact that
the cortex operates discontinuously, with “shutter” states
interspersed with the generation of wave packets (Freeman 2007).
Moreover, while eschewing the technical apparatus of decoherence,
recent work has adopted quantum field theory (Freeman et al, 2006c) to
explain the phenomenon of anomalous dispersion in the brain. Just as
the vibration induced by a blow will reach the other side of a solid
object at a different time to the sound thereof, wave packets show
properties of transmission independent of neural impulse itself. In
fact, the brain behaves in ways not dissimilar to a boson.

Freeman (2005b) introduces several other  leitmotiven.  Globally
coherent brain activity may be an objective correlate of consciousness
through preafference. Preafference, in turn, enters once the more
veridical notion of circular causality is substituted for the
stimulus-response act.Briefly, once an action is lined up, the brain
prepares the system for the sensory consequences of this action in the
preafference process. The consequences for consciousness qua process
are enormous.

Essentially, Hume was right; there is no conscious will, but there
does exist a conscious “won't”. Agency as a concept needs to be
correspondingly attenuated; when the intending of an act presents
itself to consciousness, it is experienced as a cause; consciousness
of the consequences thereof are experienced as effects.

 What is  asserted, then,  is that conscious states comprise a sparse
sample of the wave packets that embody motor commands, corollary
discharges, and pre-perceptions that we conceive as unconscious. Wave
packets embodying motor commands are the substratum for mathematical
and other abstract thought. Furthermore, focal consciousness samples
at far too slow a rate to give veridical access to  the contents of
our cortices, and nature has gifted us various mechanisms to get
around this.

Specifics of this paper

Walter states three precepts;

1.        The only evidence for consciousness other than introspective is the
existence of group behavious and goal-directed such, particularly when
both attributes are combined in hunting;
2.        Thus, it is speculated consciousness emerges around the Cambrian,
perhaps 500 million years ago;
3.        Neuropil, generically considered, is the organ for consciousness

He summaries his viewpoint thus;
“Consciousness is a biological process that is sustained by
coordination of activity in many parts of the brain of a subject who
is engaged in an action of searching for information that it needs to
cope with its environment………My hypothesis is that the summary action
is expressed in a global field of synchronized oscillation, which will
shape the next action. My conjecture is that we experience this wave
packet as consciousness”


Freeman WJ [2000] Neurodynamics: An Exploration of Mesoscopic Brain
Dynamics, London UK: Springer
Freeman, W. (2002) “How and why brains create meaning from sensory
information” International journal of bifurcation and chaos, Vol 14,
No 2 (2004), 515-530
Freeman WJ [2005a] A field-theoretic approach to understanding scale-free
neocortical dynamics
        Biological Cybernetics 2005, 92/6: 350-359
Freeman WJ [2005b] William James on Consciousness, revisited. Chaos and
Complexity letters, 1 (1) : 17-43
Freeman WJ [2006a ] Origin, structure, and role of background EEG
activity. Part 4. Neural frame simulation. Clin. Neurophysiol. 117:
Freeman WJ [2006b ] Scale-free neocortical dynamics. Encyc Comp Neurosci,
Izhikevich E [ed.].
Freeman WJ [2007] Proposed cortical ‘shutter’ in cinematographic
perception. Ch. In: Neurodynamics of Cognition and Consciousness. Kozma R
and Perlovsky L [eds.]. New York: Soringer.
Freeman WJ, Vitiello G [2006c] Nonlinear brain dynamics as macroscopic
manifestation of underlying many-body field dynamics. Physics of Life
Reviews 3: 93-118.

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