why neuroscience?

In preparation for meeting with the future of my academic career next week, I set about answering some silly interview questions. The first of these was, naturally, "why do you want to do research in neuroscience?" So I thought I'd share it, as this is the first time I think I've even put it coherently to myself...

Behavioral evolution. The field of neuroscience contains the tools that most interest me in terms of searching for patterns in the evolution of behavior. The nervous system – central and peripheral – guides all the other systems of the body through interaction with the world. From the primitive neural web of the cnidarian to the ganglia of the higher animal, it is interaction with the world that makes us what we are. I love neuroscience for attempting to associate corporeal and ethereal phenomena. I love seeking out the physiological correlates of consciousness, and the pathological correlates of behavioral dysfunction. I crave the abstraction of physiology into a medium for mind and consciousness. My own autonomic system excites when connections are made between the evolution of that medium and the evolution of the intelligence it propagates.

penrose + consciousness

Sir Roger Penrose is one of my favorite fellows. He's a mathematician who uses his intelligence to design obscure puzzle patterns simultaneously denying the emergence of consciousness from a pattern for god's sake - what more could you want in a man?

He uses an entire book - Shadows of the Mind (the "sequel" to The Emperor's New Mind) - to discuss how consciousness can't arise from a consistent mathematical system. He begins, essentially, with E=mc2: a number of superposed quantum states in the brain "work" until there is a gravitational difference between their energy and mass. The gravitational significance of this difference causes the states to collapse - or unfold - into one. This single conglomerate state then becomes one observable in the gross physical world - as an action potential in a neuron, perhaps.

At this point, Penrose would seem to agree with David Bohm's implicate order: actuality is the result of probabilistic collapses/unfolding of quantum and subquantum states. We observe light similarly. When medium of a laser absorbs particular wavelenths of light, the electrons of its atoms elevate to their highest state of energy. When so many electrons are excited to this high energy state (population inversion), they collapse together to a lower energy level which results in the emission of light, an observable condition created from a quantum conglomeration.

I have always been somewhat fearful of humanity's discovering the substrate of consciousness and applying it to artificial intelligence. It is comforting that Penrose agrees with me (!) that we will not be able to design A.I. with consciousness in the foreseeable future because it's something we are not nearly close enough to understaning, not to mention being able to coalesce and manipulate.

It is possible to suggest, then, that the connect between consciousness and brain is a physiological exploitation of the vast magnitude of activity in collapsed quantum states. This "non-algorithmic ingredient", as Penrose coins it, also jives with Bohm's suggestions of probability's role in the playing-out of the quantum universe in the gross or actual universe. Could we give our fatty brains such credit as to be the medium by which quantum states become consciousness? This is a question Penrose explores in The Emperor's New Mind, and which I will not dare attempt to disect.

Not at the moment, anyway.

More to come, then.

piaget + bohm

When we are infantile, we perceive the world in terms of transformations and continuity. When someone's head disappears behind the playpen wall, it no longer exists. And when someone's arms extend from behind a tree trunk, they are part of that tree trunk. And when that tree appears fairy-sized beside our hand, it is not because the tree is far away, but because you have discovered its untouchable miniature right in our presence. A thing happens to us between this time and adulthood that morphs that cononical perception into an interspersed mass of objects and interactions. Language.

Particularly Indo-European languages (English, French, German, etc.) are primarily based on nouns. We think, communicate and perceive based on what language has done to our interaction with the world. We fragment its natural cohesion just by the way we behold it.

Language was once verb-based... transformation-based. Native American languages, Bengali and other endangered linguistics. These were also peoples who interacted with reality as if it were all actualized in the same condition, and from the same piece of cloth and ultimately still cohesive.

inexhaustible matter

descartes. the man. cogito ergo sum, etc... the dualist.

the nature of matter, he thought, is to expand itself to occupy space and thus be susceptible to physical examination. the nature of the mind is to think. the defining characteristics of these actualities being so isolated, he surmised, they must function entirely individually. and hence consecrated was the mind-body problem.

and if matter and mind are monistic content of the larger whole?

if matter is infinite such that on many levels it is strongly influenced by consciousness, does it not follow that matter and mind may be more highly interactive than our intellectual paradigm allows?

alright. so i blogged eons ago about what it might mean if microtubules were the carriers of consciousness, and communicated by replicative and epigenetic phenomena with DNA. this remains a feasible possibility to me, but i no longer have reason to believe that microtubules and DNA would be the only instance of this mind-matter causality.

if we one day exhume that matter is inexhaustible, then it becomes plausible that mind intervenes its manifestation and directs it. which is not to say that a cup of jello might appear in the hand of a mind that desires it, or that any massive physicality would arise instantaneously. rather, i think it stands to reason that such a relationship would suggest dialectical movement's role in evolution. of everything.

of electromagnetic fields, of life, of geological shifts, of societal constructions and destructions.

societal thought invades a level of materialism that begets a communal EM field which allows the society to move harmoniously while maintaining the presence of its individuals. like plasma.

universal thought invades a level of materialism that commands a shift in organelle function in a species that causes its evolution and simultaneously the subtle evolution of everything with which it interacts.

humanity builds itself on the "shoulders of giants", or rather, their mistakes. have we not always done so at the command of collective consciousness? do inventors not materialize thoughts in response to communal misgivings? do physicists not seek to explain the existence of the world based on the way that our societies now function (or flounder, rather)? and the problems we seek to eliminate in finding the rational answer to the biggest question of them all? if we one day understand the rational of matter, will we not also comprehend our own existence and, in so doing, realize the key to our own harmonious existence?

here is my confound. i do not believe in god, and i do not believe that the universe exists at the will of humanity or its delusioned elitism. without human directive, what is universal thought explained by if not god? where does it come from? the collective minds of every eletron in existence? the Higgs boson?

the only way i can fix this dissonance is by imagining that mind and consciousness it itself something infinite that we as of yet have no means to address. and by that i am comforted enough to sleep at night. killer.

empty thoughts IX

incidentally, all this time that i've been drooling over the products of the gods of neurophilosophy, i've never really condoned or disputed any of their arguments. rather, i more or less take them in stride and create something new out of them. sometimes, arguments are that badass, what can you do? at the moment, however, i say "incidentally" because i happen to have come upon a precarious internal consensus about individuality.

i like the way Lewis Thomas puts it: multiple personalities is not a pathology - it's when they all clamor for conscious attention at once that they become a problematic condition.

nice, right? here's where it gets tricky for me. it is conceivable to me to believe in the capacity of a body to merge multiple selves, but i also favor the holism in collective consciousness of the universe. so what is it? are we all of the same energy using not only various bodies differently, but various circuits of each body differently? or are we denying the strength of fragmentation in assuming holism is the healthier, safer and more sane alternative?

speech, autism and collective consciousness

“…a creature cannot have thoughts unless it is the interpreter of the speech of another.” -Donald Davidson (1975, p. 9)

Initial response: ...what?!

Secondary response:

The man is suggesting that communication through speech is the only means by which a creature is able to generate thought, implying that language is the primary vehicle of thought, rather than vice versa. I think that's dumb. The primary vehicle of thought need not be speech; it could more than conceivably be entirely driven by behaviour.

Follow me for a minute here.

A thought can be a belief. A belief is based on the way things are in the actual world. The way things are in the actual world can be interpreted through the behaviour of creatures in the world. Even if it were true that belief emerged only in those organisms capable of interpreting the behaviour of others, it doesn’t follow that that interpretation need be of speech. Thought could be generated merely on the basis of interpretation of behaviour for which speech is not necessary.

[note: the necessity of internal language is an entirely separate issue...]

Translating this into an example - as my philosophy professors would demand is crucial to my train of thought - say two primitive children witness an avalanche of boulders cascading down a nearby mountain. They may be standing close enough to the avalanche to feel the ground shake, and that a small stone may ricochet from it’s main course and hit one child in the arm. The child, having felt the sting of the stone, generates a thought correlating bounding stones with pain, and that if such a small stone inflicts pain then standing beneath the whole cascade will deliver far worse. The child can then infer that it is a good idea to avoid being in close proximity to avalanches. And... run. The second child, having witnessed the discomfort expressed by and the fleeing of the first, may infer from his behaviour that it is wise to avoid avalanches. The first child generated a thought about avalanches based on the behaviour of the cascading boulders, and the second child generated the same thought based on the behaviour of the first child... with speech being a component of neither scenario.

Yes, it can also be provoked by speech alone if a creature were to be told by another that an approaching avalanche was potentially very harmful. However, provocation of thought about the avalanche through the latter scenario would require that the creature, in order to recognize the implication of an avalanche from only the speech of another creature, must have seen it inflict harm before in the content of the phrase “approaching avalanche” could have any meaning. This doesn't make it less likely that the creature could have a belief about the avalanche as solely regarded through speech. Rather, it suggests that witnessing an avalanche harming someone does not require speech to communicate that one might want to avoid cascading boulders...

The other confound of the "no thought without speech" theory is that it can be used to argue against thought in higher animal organisms, as people actually do make the argument that non-human animals can't communicate through speech [this is another assumption with which I have extensive arguments]. And while I'm a proponent of learning and memory being entirely biochemically and anatomically structured in some processes, there is also a component of consciousness that becomes necessary to explain the acquisition of the kind of behaviour learned in higher animals. There's a communication that occurs between human and animal in instances of learning that are not classical conditioning, which suggests thought in the mind of the animal as it interprets the behaviour of its trainer or owner, or what have you.

And then we have the instance of Davidson's awkward collision with cases of Autism. Since he purports that to be a thinker you must be a speaker interpreting other speakers, it then follows that Davidson must believe that Autistic people - who have monstrous trouble interpreting the minds of others but who can put together their own coherent thoughts (Baron-Cohen 1995; Harris 1991)- are not capable of thought. Which, as you might imagine, perplexes me. Thought, as I categorize its nature, can exist irrespective of lingual communication, and as such, does exist in the minds of autistic beings despite their inability to interpret the mental states of others through their speech. Since Davidson's original argument was way back in 1975, it's a struggle to get my hands on - but am still trying to locate - his response to this more recent confound to speech being the primary vehicle of thought, and thought being nonexistent without interpretation of speech. I imagine him saying something to the like of, "autistic beings do indeed interpret speech, they simply do so incorrectly and so they are able to have thought, but only based on fallacious interpretation." [and yes, he would use the word, fallacious]. Then again, responding as such negates Davidson's other stipulation which is that to be translated into a thought, the speech of another person must be interpreted as the speaker intended.

What I maintain is that when Davidson originally proposed this theory, it was meant to be applied to a confined arena of communication and interpretation... in that one might not be able to have correctly designed thought unless in response to the speech of others.

Here is where I skid off the rail, but where my train gets interesting.

In terms of collective consciousness... it would seem that interpretation of speech were completely devoid of purpose, and that Davidson's theory would be completely null. If we are all linked by consciousness (and that includes non-human animals on the level at which they exhibit it) then interpretation of speech is a useless tool except to distance us from being aware that collective consciousness might exist. So there we have the collective conscious arguing against the utility of speech. Then again, if collective consciousness were a fully functional medium, we would never misinterpret one another's speech... or letters... or online chatter... would we. But by the same token, would autistic beings - under the condition that they might even be able to participate in collective consciousness - cease to have this symptom of not quite being able to grasp the mental states of others as portrayed by their speech or any other means?

So perhaps, if we were, as a species - or as a kingdom of organisms, for that matter - to become aware of our collective conscious, would our interpretation of one another improve? Would we disable the function of war? Wouldn't we have a more comprehensive understanding of the international economic dynamics such that "globalization" and recession could be side-stepped entirely? Would sociology even be necessary?

And there you have it. Thought as independent of interpreting speech. Davidson, I like you. Don't say dumb shit.

dimethyltryptamine

this is a drug synthesized by the pineal gland during REM stages of sleep. it's said to have something to do with the vivid and sometimes euphoric contents of dreams, which also occur during REM. due to its otherwise elusive function in the brain/body and association with the oddball region (pineal) it has, therefore, been postulated as the chemical substance of consciousness.

"Hallucinogenic effects were seen after 0.2 and 0.4 mg/kg of dimethyltryptamine fumarate, and included a rapidly moving, brightly colored visual display of images. Auditory effects were less common. "Loss of control," associated with a brief, but overwhelming "rush," led to a dissociated state, where euphoria alternated or coexisted with anxiety. These effects completely replaced subjects' previously ongoing mental experience and were more vivid and compelling than dreams or waking awareness." (Strassman et al. 2003)

Strassman, a psychopharmacologist at U. New Mexico is one of the first to postulate that DMT is in fact synthesized in the pineal gland. although it seems to be produced in other regions of the body as well, as it has been found in urine, blood and cerebrospinal fluid (Jacob and Presti 2004), although thought to be an insignificant metabolic byproduct. i guess because DMT is synthesized from a serotonin intermediate it followed, for Strassman, that this particular tryptamine could be produced by and secreted from the pineal gland. but nobody really knows where endogenous DMT comes from, suffice if to say, the body uses a pretty wide array of tryptamines (these are primarily monoamine neurotransmitters and hallucinogens), including the melatonin and serotonin produced in the pineal.

serotonin is supposedly converted into DMT by the pineal during REM sleep, playing a role in dream activation (Callaway 1988). Strassman thinks that when these levels get too high persons experience "mystical/spiritual consciousness." he thinks - and as of yet he has no chromatographic/spectrophotometric data to suggest this - that DMT over-synthesis occurs during birth, before death, near-death experiences and deep meditation. in the 1970's, it was speculated that DMT levels might have something to do with Schizophrenia... but the results of these studies were inconclusive (Angrist et al. 1975, and others which escape me...). what i would like to see is a correlational study comparing systemic and cerebrospinal DMT in healthy control subjects to those exercising deep meditation.

in the Strassman study cited above (2003), it becomes suggested that endogenous DMT may function as did trace amounts of DMT; namely, the chemical would be a non-hallucinogenic. returning to the Calloway proposal that DMT participates in dream activation, it would seem like the job of endogenous DMT would be to do activate hallucination, not suppress it. but that's only if you're of the opinion that dreams are hallucinations...

okay, so we have an idea of how DMT acts in the brain... sort of. both DMT and it's precursor, tryptamine act through a recently identified trace amine receptor (TA, localization unidentified but interacting with the dopamine reward pathway). but since i'm mostly curious about it's production in the brain as relevant to the pineal gland and consciousness, we're going to move in that direction instead...

as noted in the Schizophrenic studies, DMT can also be found in the peripheral nervous system and systemically. this would imply that it can be synthesized outside of the brain, and this idea is supported by the systemic localization of indolethylamine-N-transferase (IMNT). IMNT is the enzyme that tryptophan to make methyltryptamine, which is methylated again to yield dimethyltryptamine. this implies two things:

1) DMT can be synthesized in peripheral tissue, and subsequently cross the blood brain barrier... which is uncharacteristic of most neurotransmitters.
2) since during the stress response the body produces excessive amounts of tryptophan, DMT has implications as a non-hallucinogenic, as proposed by Calloway...

so why does Strassman insist that endogenous DMT is produced in the pineal gland, and is a propagator of the hallucinations that deem it worth of sustaining the weight of consciousness? let's explore...

well... so aside from IMNT being part of the peripheral system, the pineal gland is home to quite a few other methyltransferases.

...that's it.

there's also the theory that DMT must be produced in the pineal because it has something to do with calcification of the gland, but that is not Strassman's theory, and even if DMT does play a role in calcification, that isn't sufficient to conclude that the tryptamine is produced there.

so you've got your aging pathology studies that note pineal calcification in response to abnormal secretion of melatonin (Sandyk and Awerbuch 1992), and your pineal calcification in response to excessive calcium influx and significantly decreased metabolic activity that would otherwise regulate calcium levels - characteristic of aging and essentially all aging pathologies (Krstic 1986).

link between calcification and melatonin? fine, i'll take it. link to dimethyltryptamine.................... come on, really? there's nothing? there gots to be something...

autonoetic awareness and episodic memory

Much of the human experience – the way we characterize ourselves as persons – can be attributed to our episodic memory. This is the ability to travel through time, in the form of recollection, to past experiences in order to know how and why we acquired certain knowledge. Episodic memory is characterized by Endel Tulving by three qualities: sense of time, self, and autonoetic awareness. He describes it as a phenomenological quality distinct to humans, and not experienced by non-human animals. But here's where it gets hazy... it is difficult to assess whether non-human animals exercise episodic memory because they can't linguistically report their personal experiences. As such, our best shot at at studying episodic memory in non-human animal models is to assess the animal’s memory of what happened, where it happened and when it happened. Because such tests do not require a consciously directed inference to memory, they are said to assess episodic-like memory.

This consciously directed inference is what Tulving called autonoetic awareness... being the directed retrieval of a specific object of memory. This is distinct from autonoetic consciousness, which Tulving does not reference in describing episodic memory, but which is important to defining the phenomenon in non-human animals. Autonoetic consciousness has no object; rather, it is the fluid link throughout one’s past memories, present, and future projections.

Autonoetic awareness requires the use of mental time travel: reliving a targeted event of the past and using it to consider possible future scenarios. Autonoetic consciousness, because it does not require identifying the context of a specific event, does not imply mental time travel. One can conceivably travel back in time along a conscious continuum without targeting a specific time and place for an event, but knowing that it occurred somewhere in the past. For example, a person knows when and where they were born without remembering the experience. It becomes difficult to assess which of the two phenomena occurs in non-human animals because they can't declare thoughts about specific events of the past. We can't assume that because non-human animals can’t verbalize mental time travel that they do not have it, and therefore do not have autonoetic awareness. This confound requires the development of tests that allow non-human animals to declare their thoughts not with verbalization, but gesture or other physical expression.

Rhesus monkeys can appropriately refuse to submit to a visual image test when they do not think they will choose the correct answers. This test design successfully demonstrates that monkeys know when they remember a learning event or not. However, it does not directly implicate mental time travel, or presume autonoetic awareness. More likely, it suggests autonoetic consciousness - knowing that a particular piece of information is lodged somewhere in memory, but not necessarily targeting it on the streamline of consciousness. Because studies like this one more closely imply autonoetic consciousness, they support the theory of episodic-like memory, and not human-like episodic memory.

Clayton and Dickinson are pretty famous for their studies on Scrub jays argue, again, that non-human animals exhibit episodic-like memory based on an experimental design which targeted two of the three qualities of episodic memory: sense of time, and self. Clayton and Dickinson designed a caching apparatus in which scrub jays could store both preferred perishable (worms), and less preferred non-perishable (peanuts) foods. After a short period away from the caching apparatus, Scrub jays preferred to recover the worms. But... after a longer delay, they chose to recover the non-perishable although less preferred food. This fairly ingeniusly exemplifies the use of autonoetic consciousness in the birds... but in spite of its brilliant layout does not speak to autonoetic awareness.

It's worth noting that an argument could be made for the presence of autonoetic awareness in scrub jays based on their ability to distinguish between a 4hr and 124hr time period. This observation (part of the Clayton/Dickinson study) suggests that the jays were able to target a general place in time when they cached both foods so as to be able to discern that the preferred food (worm) had likely decayed since. Inferring this kind of targeting argues for autonoetic awareness... However!, it may also be the case that as with the Rhesus monkeys, the 124hr delay may have allowed scrub jays simply to forget when they cached an item. It has been shown to be the case in both rat and primates modeled in similar tasks that the memory of “when” was poorer than “what,” and “where." So... if this was the case with the scrub jays, then not being able to recall exactly when they cached the food stuff, they may have recovered the less-perishable but less preferable food simply to avoid the risk that the preferred food may have decayed. The propensity of risk averse behavior in scrub jays may give stronger baring to the argument for autonoetic consciousness than autonoetic awareness... eh?


So my last blip of this rant is this: there has been insight into the anatomical component of episodic memory in humans that may provide a link between behavioral demonstrations in humans and non-human animals. In humans, the right prefrontal cortex has been identified as a key brain region in the recall of episodic memories. Given that Clayton/Dickinson claim that their experimental design targets episodic-like memory retrieval, it would be a valuable experiment to investigate the prefrontal cortex activity in these birds as they are retrieving cached food. If the same region of the prefrontal cortex is activated during this activity, it suggests the biochemical validity of the Scrub jay findings. However, the Scrub jay is evolutionarily several orders of phylogeny removed from humans... this presents the confound of their significantly less developed prefrontal cortex. In the primate and rat models of episodic-like memory, it would be invaluable to compare a PET assessment of right prefrontal cortex activity during memory tasks. If, in the primate model, there were both a behavioral correlate in episodic-like memory tasks and activity in the right prefrontal cortex, we might be able to definitively say that animals experience episodic memory in the same way that humans do. That is, that they exercise sense of self, time and autonoetic awareness.

For now, we are only able to infer that non-human animals exhibit episodic-like memory. It remains to be concluded whether non-human animals exercise autonoetic consciousness or awareness. Determining which phenomenon is occuring will give greater insight into the behavior of non-human animals, and better address the question of whether episodic-like memory is as close to episodic memory as non-human animals get. It is entirely possible that non-human animals have only episodic-like memory because they have autonoetic consciousness, and not autonoetic awareness. However, it may also be the case that we have not found a way to enable non-human animals to declare their past experiences in a suitable way...

supervenience of subconsciousness

“It is clear that there is no more of a conceptual entailment from biochemistry to consciousness than there is from silicon of from a group of homunculi…. So consciousness fails to logically supervene on the physical.”

Chalmers is suggesting that consciousness can't be reduced to a physical structure or property because the silicon model of neural circuitry is functionally identical to biochemical neural circuitry, yet the silicon model can't exhibit consciousness. This is an assumption that silicon and neural circuits are identical... but I would contend that there is a “conceptual entailment from biochemistry” that provides a physical property on which consciousness may very well supervene.

The difference between a silicon and neural circuit is plainly that the former is closed and the latter is open... such that the electrical flow of messages through each respective circuit may occur in the same phenomenological fashion, but not the same physical fashion. Namely, when circulating an electrical signal, a closed circuit releases energy only in the form of heat, whereas an open circuit releases energy as mostly Gibbs free energy with the ability to do work, and very little heat. A silicon circuit is not self propagating, namely, through its path it meets only with resistors and inductors which cause it to dissipate heat. However, a neuronal signal is self propagating, and free energy in its environment is both consumed and produced by that process. This, of course, is assuming that energy and heat are physical properties on which consciousness might supervene. Since the free energy has the capacity to perform work, and heat does not, the neural circuit is the one with the ability to support consciousness.
Because free energy is undefined aside from its ability to do work, it is possible that this particular physical property is the medium through which neural structure and consciousness are connected. Therefore, I propose that the changes in free energy that occur during electrical signal propagation in a neural circuit may be the physical cause of consciousness. Free energy, being the physical difference between a neural and silicon circuit, would explain consciousness arising in one and not the other, and provide a physical property to which consciousness might be reduced.

But all this... is written out of fear. If humans manage during my lifetime to find the physical matter of consciousness such that we can replicate it... my soul will crumble, and my fascination with the human condition will suffer a dreadful, murderous demise. As a neurochemist, I need for there to be some manner of correlation between biochemistry and consciousness. As a mind, I need for that matter to be untouchable, and irreplicable.