Tag: consciousness

After Z

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The nights and days collide with violence. There is the nocturnal me and the dazed, daylight version squinting away from the glaring windows. There are the catnaps that lace with riotous algebras. I am addicted to caffeine, or run on it, until even it becomes unpersuasive, and I droop over at the keyboard. Then this pulse of creation pulls me out again, stunned for a few beats, and I grasp my mug and stumble back to the lab floor.

Z keeps changing, day by day, midnights into dawns, and reawakening in clanging novelty. Z is for “zombie,” for it is in the uncanny valley of both a physical and cogitating thing. It perceives, stands, jogs in place beside me on the laboratory floor, an ochre braid of wires bouncing in a dreadlock mass behind it. Z plays chess, folds towels (how hard that was!), argues politics (how insane is that one!), and constantly restructures nuances in its faces and gestures. Sometimes I’m tired and Z is an impertinent teenager. Often there are substitutions and semantic scrambling like a foreigner who mistakes a word for another, then carries on in a fugue of incoherence.

There is a half-acre of supercooled GPUs to the north of the lab where the hot churn of work is happening. It’s a spread of parallel dreamscapes, each funneled the new daily stimuli, stacking them into a training pool, then rerunning the simulations, splitting and recombining, then trying again to minimize the incoherency, the errors, and the size of the model. Of the ten thousand fermenting together, one becomes the new Z for a few hours, but then is gone again by morning, replaced by a child of sorts that harbors the successes but sheds the excesses and broken motifs.… Read the rest

We Are Weak Chaos

Mark Davis1 Comment

Recent work in deep learning networks has been largely driven by the capacity of modern computing systems to compute gradient descent over very large networks. We use gaming cards with GPUs that are great for parallel processing to perform the matrix multiplications and summations that are the primitive operations central to artificial neural network formalisms. Conceptually, another primary advance is the pre-training of networks as autocorrelators that helps with smoothing out later “fine tuning” training programs over other data. There are some additional contributions that are notable in impact and that reintroduce the rather old idea of recurrent neural networks, networks with outputs attached back to inputs that create resonant kinds of running states within the network. The original motivation of such architectures was to emulate the vast interconnectivity of real neural systems and to capture a more temporal appreciation of data where past states affect ongoing processing, rather than a pure feed-through architecture. Neural networks are already nonlinear systems, so adding recurrence just ups the complexity of trying to figure out how to train them. Treating them as black boxes and using evolutionary algorithms was fashionable for me in the 90s, though the computing capabilities just weren’t up for anything other than small systems, as I found out when chastised for overusing a Cray at Los Alamos.

But does any of this have anything to do with real brain systems? Perhaps. Here’s Toker, et. al. “Consciousness is supported by near-critical slow cortical electrodynamics,” in Proceedings of the National Academy of Sciences (with the unenviable acronym PNAS). The researchers and clinicians studied the electrical activity of macaque and human brains in a wide variety of states: epileptics undergoing seizures, macaque monkeys sleeping, people on LSD, those under the effects of anesthesia, and people with disorders of consciousness.… Read the rest

Contingency and Irreducibility

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JaredTarbell2Thomas Nagel returns to defend his doubt concerning the completeness—if not the efficacy—of materialism in the explanation of mental phenomena in the New York Times. He quickly lays out the possibilities:

  1. Consciousness is an easy product of neurophysiological processes
  2. Consciousness is an illusion
  3. Consciousness is a fluke side-effect of other processes
  4. Consciousness is a divine property supervened on the physical world

Nagel arrives at a conclusion that all four are incorrect and that a naturalistic explanation is possible that isn’t “merely” (1), but that is at least (1), yet something more. I previously commented on the argument, here, but the refinement of the specifications requires a more targeted response.

Let’s call Nagel’s new perspective Theory 1+ for simplicity. What form might 1+ take on? For Nagel, the notion seems to be a combination of Chalmers-style qualia combined with a deep appreciation for the contingencies that factor into the personal evolution of individual consciousness. The latter is certainly redundant in that individuality must be absolutely tied to personal experiences and narratives.

We might be able to get some traction on this concept by looking to biological evolution, though “ontogeny recapitulates phylogeny” is about as close as we can get to the topic because any kind of evolutionary psychology must be looking for patterns that reinforce the interpretation of basic aspects of cognitive evolution (sex, reproduction, etc.) rather than explore the more numinous aspects of conscious development. So we might instead look for parallel theories that focus on the uniqueness of outcomes, that reify the temporal evolution without reference to controlling biology, and we get to ideas like uncomputability as a backstop. More specifically, we can explore ideas like computational irreducibility to support the development of Nagel’s new theory; insofar as the environment lapses towards weak predictability, a consciousness that self-observes, regulates, and builds many complex models and metamodels is superior to those that do not.… Read the rest