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This is an archive version of 'Psychedelic Information Theory' Alpha chapters. The final version of this text can be found at:
This is Your Brain

James Kent

Chapter 09: Psychedelic Information Theory

Signals & Circuits: The Human Operating System

Everything you experience, know, think and feel is mediated by one very essential organ: the brain. The brain is made up of roughly one hundred billion neurons, and as we have seen, neurons are very complex structures. But it is the localized groupings of neurons (clusters) and the intricate ways these clusters interconnect (networks) that make us who we are. These task-specific clusters of networks are all crammed into a very tiny space in our skulls, but are vital to all the processing of sense, motor, and logic data we do at every second of every day. Each section of the brain is wired for its own specific task, and each section of the brain communicates with other sections of the brain in very specific ways. When these localized clusters are all functioning properly, we get the emergence of consciousness, with all of the waking activity, sleeping, happiness, sadness, excitement, boredom, passion, and anguish that goes along with it.

For the most part, the macrostructure of the brain is genetically determined; and at very basic levels our neural wiring is all the same. But every brain is different, and each region of your brain may have built-in advantages or disadvantages depending on heredity profiles, environmental factors, and your gender. All people are different; this is true. Men are different from women; this is obvious from both brain structure and behavior. Everyone experiences and makes meaning from the world a little bit differently, adapting to their weaknesses and playing to their strengths. That we can agree on anything — let alone all interact and co-exist for so long without complete mass choas — is a testament to flexible genetic design and the stubborn strength of human will. Like a muscle, the brain can adapt to the burden of the task before it, and when put to the right task it can thrive and grow. Building complex, industrialized, technological societies is not a human trait per se, but we developed thumbs and got a better grip on our tools before some other organism beat us to the idea, so civilization became a distinctly human domain.

And once the early hominids could manipulate tools, the brain took off, growing and learning new skills that tool-use made possible. And before long we were using the same tool-manipulating areas of our brains for manipulating abstract tools like symbols and concepts, tools that could allow us to think, plan, communicate, and eventually turn our abstract dreams into hard reality. All of this was made possible by the brain,its bottom-up awareness of reality coupled with the top-down control of the body to accomplish its will. And by flexing this logic-processing organ we have been rewarded with bigger and ever more complex brains, evolving over the millennia from crude sense processing networks into layered bundles of parallel, multi-threaded logic circuitry capable of all sorts of associative reasoning. Language, art, poetry, music, cities, technology... everything we produce exists in our brains first as concepts and then as symbols that can be transmitted from brain to brain, which is the basis of all communication, community, society, and civilization. And this is all made possible by complex logic processing circuits that not only allow us to envision the dream, but also allow us to manipulate tools — abstract and concrete — for turning our dreams into reality. Homo sapiens is a mind-manifesting organism: curious, creative, imaginative, adaptive, resourceful... We are all driven by the psychedelic impulse in one way or another.

But the psychedelic organism, the human being, did not erupt spontaneously. The human brain evolved over billions of years, bit by bit, little by little, and some areas of our brain are much older than others. We may be thinking and reasoning apes, but at the core of our brains we are still mostly apes with a few thin layers of human logic networking laid over the top. And as anyone who has fought in a war or been involved in a riot or other mass hysteria event can tell you, that tiny bit of rationality that separates us from the beasts can crumble away in a second with the proper stimulus. We pride ourselves on our civilized manners and keen reasoning abilities, but when our backs are to the wall, those higher parts of us are gone and the beast is let loose. Though we are capable of great feats of logic, it is still the ancient primal instincts that rule us all.

For nearly a century now, scientists have been arguing about how much of our behavior is ruled by primal instinct and how much is ruled by higher-level rational thinking, but only recently has the proper research been done to show how the different areas of our brain influence one another in our decision-making processes. While it would be nice to say that everyone behaves the same way, we now know that everyone responds to stimuli in slightly different ways, and these differences in response can be directly mapped to subtle differences in neural wiring. As I said earlier, everyone's brain is wired in basically the same way, but the extent to which specific synaptic pathways are strengthened between various brain organs is different for every individual, based on genetics and conditioning. Some people are very effective at overriding their primal instincts, and other people are impulsive; other people wilfully ignore their rational brains and live totally by their instincts. There are very simple neural correlates for all of these behavioral types, and understanding the ways in which our brains process reality will help us in developing a comprehensive model of psychedelic action on the senses, the psyche, and the self.

Brains Organs and Function: The Schematic

Figure 4: This is Your Brain

For all its mystery and majesty, the brain is really nothing more than an elaborate set of signal and logic processing circuits bundled together in our skulls. But this elaborate network of circuits makes us who we are; it defines everything about our personality from perception to intelligence to behavior. In addition to dutifully interpreting sense data, our brains also filter, modify, and fill-in missing sections of data needed to create a more holistically pleasing picture of reality that imparts some kind of relevant information — or meaning — about our surroundings. This construction of meaning from raw sense data and the execution of actions based on that meaning is what the brain is all about. Mediating organism input (sense data) and output (behavior) is what the brain is all about.

Despite the high level of detail we experience in the world we live in, the reality we perceive from moment to moment is not hard data; it is a filtered and smoothed holistic representation formed in our working memories from a merging of data passed upwards from a series of lower sense processing organs to our "conscious self", which analyzes data and manages tasks in the higher cortex. A great deal of the data we receive at any one time is simply shut out of our conscious minds because it is functionally irrelevant to our moment-to-moment doings, but that does not mean it is not there or that it doesn't register in our subconscious somewhere. And as you might imagine, any change or disruption in the process of filtering and reconstructing reality in the mind's eye could lead to profound perceptual results, including the profound enhancement of sub-perceptual reality and/or the profound obfuscation of anything even remotely resembling reality. So before we jump into the nitty-gritty of sense data processing and psychedelic action, let's take a moment to look at the major brain areas and functions to get a general map of the territory we will be discussing when we apply cognitive theory to the psychedelic model.

Notes on names of brain areas:

Most brain areas are named by where they are located or what they look like, but to make it sound cooler scientists do it in Latin. I mean, you don't want to go calling a specific area of the brain, "That part on the very front of the brain, towards the top, a little to one side," so instead they call it the dorsolateral prefrontal cortex, which is Latin for "To the back and side (dorso-lateral) of the very front part (prefrontal) of the outer layer (cortex) of the brain." I know they do this just to confuse you, so I have included this handy little reference to help you find your way around through the fog that descends whenever Latin is trotted out.

Formal & Functional Terms

Rostral — upwards, towards the head
Caudal — beneath or behind, towards the tail
Dorsal — on the back or upper surface
Ventral — towards the belly or lower surface
Medial — towards the middle or interior
Basal — at the base
Lateral — to the side
Ipsilateral — on or affecting the same side
Contralateral — on or affecting the opposite side
Anterior — towards the front
Posterior — towards the rear
Superior — on top of or above
Inferior — underneath
Interior — on the inside or in the middle
Afferent — carrying signal towards the brain
Efferent — carrying signal away from the brain

Anatomical terms:

Stria — Any nerve fiber or neural signal conduit
Gyrus — Any of the many folded layers of the cortex
Sulcus — Any large fissure or groove that separates the areas of the cortex
Encephalon — Inside the head

Other areas of the brain are named for the people who discovered them, and you'll just have to figure those out on your own, but I'll do my best to keep the science-speak to a minimum here, or to translate the Latin where it seems appropriate. So let's open the hood and take a look at the parts, shall we?

The Spinal Cord

The good old spinal cord, it carries somatic signals from the body to the brainstem and mediates signals essential to tactile feedback and motor behavior. No organ better demonstrates that signal flow is intimately connected with sensory awareness and consciousness. If you sever the spinal cord you lose signal from the body and it disappears from the brain altogether. Signal flow is awareness, remember that.

The Brainstem & Medulla

A very old part of the brain that houses our primal autonomic systems, responsible for heartbeat, respiration, hormonal response, and the basics of vertebrate life. Sometimes called the lower brain, the reptilian brain, or the animal brain, the brainstem represents a very crude form of consciousness that is pre-verbal, pre-cognitive, and pre-emotional. The brainstem is barely self-aware but is able to carry out essential survival behaviors in reaction to environmental stimuli.

From the junction where the spinal cord hits the brainstem, a variety of small task-specific organs emerge. First there is the medulla oblongata (middle round part), then the pons (literally a bridge), the midbrain (or mesencephalon), and at the top of the brainstem the diencephalon, which merges into the thalamus and the limbic system (also known as the emotional brain). Each of these brainstem areas has even smaller task-specifc organs, but if you see words like medullar or pontine or diencephalic when discussing various brain functions, you now know they mean various areas of the brainstem. All of these structures are vital to survival and the proper functioning of the brain, but I'll pick a couple of areas to discuss in a little more detail. First, the medulla oblongata is the most basic element of the working vertebrate brain, and is probably very similar in structure to the very first vertebrate brain that came into being so many millions of years ago. It controls the very essentials of life: heartbeat, respiration, circulation; it routes primal sensory signals from the brain to spinal cord; it detects motion and position of the body and keeps us oriented; it mediates some very basic involuntary responses to stimuli, such as pre-cognitive avoidance reactions in response to pain, loud noise, and danger; and pre-cognitive seeking actions in response to hunger and food. The medulla is also where sense data from the ear and tongue first hit the brain for further routing and processing, illustrating the point that sound and taste (like touch) can have a very primal, instinctual, pre-cognitive influence on us.

Pons and Midbrain

The pons and midbrain are still part of the brainstem and sit above the medulla and contain a variety of smaller organs — neuronal nuclei — essential to mediating brain function. Most interesting for our purposes are the areas that produce the endogenous amines, such as dopamine, serotonin, and norepinephrine. Serotonin is projected upward from neural clusters in the pons known as the raphe nuclei in the reticular formation. The neuronal clusters that send dopamine up into the brain are located in the ventral tegmentum (on the lower part of the midbrain) and the substantia nigra (black substance, so-called since it contains the dark pigment melanin, which literally contains bundles of indoleamine and catecholamine precursors all linked together). Norepinephrine (noradrenaline), which is released as a motivator in response to stress on the body, is also produced in an area of the pons called the locus coeruleus. Acetylcholine is produced in the pons as well, in the cholinergic nuclei, and generated upward into the brain, but it is also produced in an area called the basal forebrain, which is the base (of course) of the front part of the brain at the top of the brainstem. As you can see, this area of the brain is essential to mediating mood response, and is heavily networked with connections from both sensory pathways and neuronal feedback from other parts of the brain, and manages most of the involuntary responses our bodies have to both danger (fight or flight) and pleasure (mating and reproduction).

Diencephalon, Thalamus, Hypothalamus, & Pineal Gland

The diencephalon sits at the top of the brainstem and is the focal point of a lot of signal action. The major component of this area is the thalamus, which is like the grand central switching station for the brain, screening and routing sensory signals from the body, eyes, ears, and tongue up to the higher cortical areas for processing, as well as receiving feedback from the cortex to mediate pre-cognitive sensory screening. The hypothalamus hangs off the front of the thalamus and is another major player in the emotional brain, controlling hunger, thirst, body temperature, waking and sleeping activity, hormonal response, sex drive, and anger, as well as pleasure and reward pathways. Since it controls the circadian rhythms of the body (hunger cycles, sleep cycles, mating cycles, etc.) the hypothalamus is sometimes referred to as the "internal clock" for the body. Also instrumental in keeping the body's rhythms in check is the pineal gland. Sitting right in the middle of the brain — between the rear lobes of either side of the thalamus — the pineal gland is sometimes called the "third eye." Once thought to be a vestigial light sensor and sometimes considered to be the "seat of the soul," the pineal gland is responsive to light stimulation from the retina and influences the circadian rhythms of the hypothalamus via melatonin secretion. All of these areas are central to the functioning of the emotional brain, and have been widely implicated in the actions of psychedelic drugs.

Limbic System, Hippocampus, & Amygdala

Sometimes called the "emotional brain," the limbic system comprises a layer of organs and neuronal nuclei that sit roughly between the higher levels of the brainstem and the lower levels of the cortex. In addition to the thalamus, hypothalamus, and pineal gland, the limbic system also includes the cingulate gyrus, the hippocampus, and the amygdala. The cingulate gyrus is a primitive layer of cortical folds that receives sensory input from the anterior nucleus (front part) of the thalamus and is thought to influence emotional response to sensory stimuli within the limbic system. The hippocampus (Latin for "sea-horse") is located deep in the temporal lobe and is considered to play an important role in contextualizing emotional information in response to pleasure and aversion stimulus and the coding of long-term memory. The amygdala (Latin for "almond shaped") is also located deep in the temporal lobe and is instrumental in processing fear and aggression as well as pleasurable response to stimulus. The olfactory cortex (which integrates sense data from the nose) is also tied intricately into the limbic system, which we will look at in more detail when discussing the sense of smell. Of course, organs in the limbic system, which plays a major role in emotion and memory, are highly implicated in the action of psychedelic drugs.

The Cortical Hemispheres, Lobes, and Specialized Areas

The cortex is the primary logic processing circuitry of our brains, and consists of a wide membrane of stacked neural cells that is folded and convoluted to maximize surface area within the tiny space that is the cranial cavity. These folded and crumpled cortical layers make up the hardware of our entire conscious interaction with the world. All cognitive sensory awareness occurs in the cortex; all "thinking" occurs in the cortex; all language and visual imagination occur in the cortex. The cortex is the playground of the mind, the very map of who we are, and each tiny fold and surface area of the cortex has its own specialized processes to handle in the emergent gestalt that is consciousness. So let's cut this sucker up and see how it works.

The Hemispheres: Left Brain vs. Right Brain

The majority of sense data is passed to the cortex via thalamocortical projections that ascend from (you guessed it) the thalamus to corresponding processing areas in the higher cortex. The main mass of the cerebral cortex is split into two hemispheres (left and right), and like most areas of the body, these two halves are roughly mirror opposites of each other. It is widely believed that left and right brain differ fundamentally in the types of information they process, the left brain being associated with parsing logical, sequential data while the right brain is more adept at synthesizing intuitive, holistic patterns within the entire body of data. In truth it is not that simple, and the two hemispheres interact in a wide number of ways both specialized and complimentary. There are also massive numbers of neural connections running between corresponding sites on either side of the cortex, making it more of a stereo parallel processing circuit as opposed to the specialized dual-threaded process that a Left Brain vs. Right Brain model implies. However, lesion studies have shown the Left Brain vs. Right Brain metaphor is accurate to a point, especially when fine attention to detail (Left Brain) and wide associative leaps (Right Brain) are needed in language processing.

The surface of the cerebral hemispheres are generally separated into four different areas, or lobes, and each lobe is responsible for specific tasks related to consciousness. Let's take a look at the frontal lobes first, since they comprise much of the networking that makes us unique individuals.

Frontal Lobes

The frontal lobes of the cerebral cortex, and more particularly the prefrontal cortex (PFC, or "front part" of the frontal lobes) are associated with conscious identity, working memory, learning, long-term planning, and the executive self, which is the part of the brain responsible for aggregating sense data and making voluntary behavioral decisions based on logical processing of those data. While the prefrontal lobes store short term memory, the inferior frontal region known as Broca's area is where speech originates — both when we speak to others and when we speak to ourselves (as in internal dialogue or thinking, which uses the same pathways as speech but without the activation of the motor cortex to make the mouth move). The frontal lobes aggregate and contextualize sense data to create our moment-to-moment picture of reality, and communicate via feedback loops with other areas of the brain to control both voluntary and involuntary activity. Conscious ideation, visualization, planning, thinking, and contextualization of self are all frontal lobe activities. It would be a gross oversimplification to call this area the "mind," but it would not be a stretch to call it "ego." We will be examining more of the specialized functions of the frontal lobes and their feedback pathways with other circuits a bit later in this section.

Temporal Lobes

Of all the brain areas, the temporal lobes are most associated with the strange and bizarre. These lobes rest along the underside of either side of the cortex like headphones, and are responsible for primary audio processing, primary olfactory processing, pattern recognition, emotional processing (along with the limbic system), and long-term memory processing (along with the hippocampus). In addition to being the primary area of interest for audio hallucinations and many synesthetic components of the psychedelic state, the temporal lobes have also been implicated in the eruption of spontaneous mystical states via temporal lobe seizures or artificial temporal lobe stimulation with electrical probes. This unique trait led to the temporal lobes being dubbed the "God Module" in the mainstream press around 1997, and popular speculation about religion being hard-wired into this area of the brain have persisted ever since. Temporal lobe epilepsy can cause overly religious, mystical, and messianic behaviors that affect a person for life. No other area of the brain seems to produce such profound effects. Of course, when we talk about drug-induced mystical experiences it is important to keep the temporal lobes in mind. These lobes are implicated as one of the (if not the) key players in mediating the most sought-after affects of the entheogenic experience. We will be coming back to the temporal cortex many times when discussing sound processing, audio hallucinations, and mystical experiences in greater detail.

Occipital Lobes

Sitting on the very back of the cerebral cortex are the occipital lobes, and what is interesting about the occipital lobes is that they are the primary visual cortex of the brain. That's right, this area in the very back of the brain is where sight is processed, much like a movie projector shining light through the cornea and projecting it from the retina to the back wall of the cranial cavity. Everything we "see", we see because signal makes it to this area of the brain; and if electrical activity happens in this area of the brain, we see it. Of course, this area is primarily implicated in visual perceptual distortions and visual hallucinations under the influence of psychedelics, so we will be examining the processes of the visual cortex in detail later.

Parietal Lobes

The parietal lobes are famous for being both the primary area for processing the sensation of touch as well processing all outgoing motor commands. The parietal lobes essentially are the awareness of the body in the cortical mind, receiving sensation, sending motor commands, and processing spatial awareness data. This area of the brain also specializes in the logical manipulation of abstract concepts — such as the numbers and symbols of mathematics — which are basically internalized representations of our physical world, and thus very much like our spatial reasoning activities. The occurrence of somatic sensation and tactile hallucinations in the psychedelic state would certainly implicate the stimulation of the parietal lobes in some sense, though if that were true one would assume that psychedelics might also have a corresponding effect on spontaneous motor activity as well. The reporting on spontaneous motor activity under the influence of psychedelics is spotty — surely far less than those reporting tactile hallucinations — so we will look at this dichotomy a little later when discussing tactile hallucinations and other somatic phenomena.

Is that all?

Believe it or not, we now have our functional schematic of the brain. Sense data enters through the brainstem, is processed for emotional and involuntary response in the higher brainstem and limbic system, and is then passed to the corresponding area of the cortex for final processing and holistic integration in the PFC. And that's it! Hard to believe such a complex organism can be deconstructed so completely, but we've covered almost the entire brain with the exception of the cerebellum, which is at the back of the brain, behind the pons and under the occipital lobes (visual cortex), and is primarily responsible for coordinated movement and fine motor control. We will not be discussing the cerebellum in much detail in this text, but be happy it is there to record and play back little things (like brushing your teeth) so you don't have to consciously think of each step of every task every time you want to do something. Of course there are important little bits and pieces of the brain I have left out, but I can't cover them all within this brief introduction. But by the time we are done with this section we will be very familiar with all the essential bits of the brain implicated in psychedelic action.

But Where is Mind?

While we have identified the specialized functions of each of the major brain areas, we have still not identified specifically where "Mind" emerges. It is tempting to say that Mind is in the prefrontal cortex (or PFC), the working brain that manages moment-to-moment task processing and awareness, but the PFC is just the one part of mind, the analytical actor of self and ego, the "logical homunculus" in the control tower that dictates conscious behavior. But there is more to mind than that, and our emotions sway us just as heavily as our logical rationales. The logical mind and the emotional mind are not two separate things, but they are both part of the same multi-threaded cascading parallel feedback circuit, which means that mind is the emergent gestalt of all these networks performing specialized threaded processes in concert. If you damage one of these areas, the mind is also diminished in some way. Conversely, if you artificially stimulate one of these areas, the mind is fundamentally altered in some way. All of these process interact seamlessly with one another, and they are all responsible for giving us our "consciousness": both the pre-cognitive and cognitive awareness of the self interacting in the "now." When these areas are awake, manipulating signal, and running their processes, Mind is active and alive.

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Tags : psychedelic
Rating : Teen - Drugs
Posted on: 2005-04-13 00:00:00