Tuesday, January 4, 2011

Deep Travel, Part 1: SEEKING System, Snipers, and Sensorimotor Rhythm

(the evocative cover of the 1982 Roxy Music album Avalon. In the legends of Arthurian Romance, Avalon is the mysterious island where Excalibur was forged and where King Arthur himself was taken after sustaining terrible wounds in his battle with Mordred)

The next two posts will highlight research by the prolific travel writer Tony Hiss into a phenomenon that Hiss refers to as "Deep Travel." Deep Travel is perhaps best described as a mental state of wide-angled awareness, one that seems to prepare the brain for generating insights and a kind of accelerated learning.

Deep Travel: Different from Focused Attention

The traditional description of heightened attention is one of laser-like focus on a particular task; the subject "loses himself" in this activity. Various sources will claim that there is a pleasurable, even narcotic effect as the subject becomes more skilled at the activity in question and is able to perform at a high level while ignoring extraneous information in the environment.

This type of rapt attention demands that the brain's working memory resources be concentrated on executing one immediate task (although the attention can switch from one task to another rapidly, as is the case in many athletic endeavors). Deep Travel as Hiss describes it is quite different: the intensity of the experience may be similar, but the subject feels like an observer who is removed from the current situation and able to view it holistically, often developing a more systematic view of interconnected elements in the world. With the "wide-angle" attentional lens comes the ability to perceive larger and larger patterns, patterns that might escape us if we are living life by careening between bursts of rumination and inner dialogue on the one hand and focused attention on specific, immediate tasks on the other.

The whole thing is quite difficult to describe, but the entry point is something like a loaded pause in the subjective experience of reality---the attention is sharp, as in focused attention, but there is no immediately pressing task to consume mental resources. As Hiss puts it, the experience of Deep Travel is akin to somehow "waking up while you are still awake."

Linking the SEEKING System with Sensorimotor Rhythm

I have had quite a bit of difficulty qualifying such a subjective experience in anything approximating precise terms. The post today will attempt to link the SEEKING emotional command system (a neural circuit within the brain which encourages exploration by creating a pleasurable sense of reward-anticipation, priming the brain for learning, and "organizing behaviors...that have proven adaptive in the face of life-changing circumstances during the evolutionary history of the species") with the onset of a mysterious brain-wave pattern that has been termed the sensorimotor rhythm, or SMR.

The post that follows this one will actually connect the sensorimotor rhythm with Deep Travel. Much of the second post will really be about paraphrasing Hiss. Hiss believes that in our modern environment the SMR is most frequently encountered when we are engaged in Deep Travel, a period when heightened alertness paradoxically combines slowly coiling physiological tension with a quiet mind and a relaxed body.

Revisiting the Seeking System

A previous post briefly discussed Jaak Panksepp's pioneering work on the emotional circuits underlying the brain's limbic system. When stimulated electrically, the circuits---Panksepp refers to them as the "emotional command system"---trigger distinct emotional reactions in study animals.

A brief recap: the emotional command system (ECS) appears to be organized broadly along an "approach-withdrawal" continuum: features of the environment that the brain should favor for survival or reproduction are granted "approach salience" and are attended to with positive emotions, encouraging the animal to pursue behavior in the beneficial direction, and, in the case of higher mammals, to employ reasoned strategies in support of them. On the other hand, features of the environment that are threats to the animal's ability to survive or reproduce are classified as "withdrawal salient" and are attended to with negative emotions, which of course encourage the animal to do something to get away from this bad stuff so that the negative emotions stop.

An unfortunate feature of the modern world is that this negative system, which really evolved to deal with short-term, very exciting problems like marsupial lions or equivalents, can become chronically overstimulated, which in turn can create a host of physical and psychological health issues.

For me, perhaps the most interesting aspects of the Panksepp work are found in the circuit that Jaak calls the SEEKING system. SEEKING employs dopamine pathways in the brain to reward learning and exploration. As noted in the previous blog entry, one form of aggression---so-called predatory aggression---appears to be deeply linked to this circuit. Predatory aggression is rewarded as fun---the SEEKING circuit has evolved to make the experience of hunting prey items to be quite pleasurable for mammalian predators (in other words, cats are not emotionally neutral about stalking and killing mice; their brains are wired to enjoy the experience).

In contrast, territorial aggression related to dominance hierarchies, self-defense, and status fights is mediated by an unpleasant RAGE circuit. Animals do not enjoy territorial aggression---it involves a feeling of being threatened and cornered; territorial aggression is an angry experience that is triggered in response to threats (in social situations, human can find threats in both physical form and in a toxic psychological form that was described previously using the acronym "SCARF"). Territorial aggression carries with it great risks of injury and loss of status---witness the extensive scars marring the bodies of extremely aggressive bull elephant seals---and thus this emotion is an expensive, necessary evil in limbic system terms.

*I placed a more technical and precise quote about the SEEKING system's function at the end of today's post.

Humans Hunting Humans

There are a number of very interesting research possibilities that stem from this contrast between aggression types and associated emotional rewards. Studies of psychopathic killers, for example, often reveal that they think of other people as members of a different species. If this was quite literal, it could help to explain why such vicious individuals actually take pleasure in hurting their victims; perhaps a SEEKER circuit meant to reward successful hunting behavior has become linked to same-species predation.

Viewing aggression types and their emotional correlates in a different context, the Army Special Forces Special Operations Target Interdiction Course (SOTIC)---a sniper program with few rivals---has distinguished between "no shoot" and "one shoot" snipers. A "no shoot" sniper ultimately finds that he is unable to shoot another human being in the cold, methodical manner in which a sniper must operate. A "one shoot" sniper can do it once, but then relives that experience again and again as a type of psychological trauma. He finds himself unable to perform the actions a second time (often this individual is able to self-diagnose the problem and remove himself from sniper duty).

The SOTIC staff estimates that a surprisingly large percentage of sniper-trained soldiers, most of whom would prove to be very able warriors in an infantry firefight environment, will fall into one of these categories (note that this applies to snipers placed in a military battlefield context and given a high degree of self-direction when it comes to target selection; the sniper-like "designated marksman" attached to a squad will probably be engaging targets who are firing upon or otherwise threatening his unit---this is very different in terms of imposed psychological demands).

Perhaps experienced snipers are able to continue to hone their fieldcraft and shooting skills and eliminate enemy personnel because they have successfully shifted to a predatory aggression model in which the enemy soldier or insurgent is dehumanized and viewed as a natural prey item. Such a sniper could well find the process of stalking, glassing, and "interdicting" an enemy to be a pleasurable emotional experience. On the other hand, the no-shoot and one-shoot snipers may be unable to make this switch; they may require the immediacy and emotional content of a pressing enemy threat in order to generate the controlled anger---the territorial aggression, in other words---to fight with lethal force.

Enjoyable Killing: Interspecies Predatory Aggression and SEEKING circuits

As stated previously, solitary apex predators like Siberian tigers are not configured for the Machiavellian social demands of dominance hierarchies and territorial types of aggression. They are not pack animals, so they don't have an "alpha" structure with an attendant leadership position.

With human beings, who are wired for both types of aggression, there is the potential for interesting shifts to take place. I recently attended a very well-done lecture by a mental health professional and serious acolyte of the fighting arts who had worked in hospital settings in New Orleans. He has had the opportunity to interview many predatory criminals. One fascinating piece of the lecture described how the criminals would refer to armed robbery, muggings, burglary, and so on simply as "getting paid." They viewed it as a basic vocational activity, something that was morally neutral, if not justified by unfair socio-economic conditions.

When their victims fought back, however, the criminals described the situation as having changed to one in which the predator who used violence against his target was simply acting in self defense: "I was there, just trying to get paid, when he challenged me and I had to put him down." The ability to see how the act of predation provoked a morally authorized counter from the victim had been lost. The predator saw himself as being challenged, a very dangerous position for someone who had lived in violent street and prison hierarchies and seen how signs of weakness led to all kinds of problems.

Thus we may find at some stage of clinical sophistication that the initial stages of a mugging---a period that Mike Tyson said he particularly enjoyed as a young Brooklyn thug because he felt that he was being crafty and "outsmarting" his targets---are associated with this pleasurable SEEKING-circuit experience of predatory aggression and stalking, while a challenge made by the victim causes a volatile flash of rage that is associated with the RAGE circuit and the territorial form of aggression. This is conjecture on my part, and hopefully future research will illuminate the changes in brain activity that occur during a criminal assault.

(raised by the Samurai to hunt wild boar and bear, Akitas are known for combining territorial and predatory aggression drives in one formidable canine package. Here we see that even legendary MMA fighters can be dominated by these animals---Randy looks like he is very close to tapping out in submission, while his young tormentor is already looking for his next target)

An interesting question has been one of what happens within the brain when the SEEKING system is being pleasurably deployed. What is the subjective experience of SEEKING meant to feel like? The reward for learning a skill or piece of information is associated with a dopamine wave and satisfaction. What happens on the way there? What keeps us on the journey?

One possible answer to these questions is that the brain has a special training mode wherein the laser of attention becomes a broad-beamed floodlight. In some cases, there is a pause or break between different states of consciousness that prepares the brain---perhaps the SEEKING system in particular---for finding those "approach" and "withdrawal" clues.

The pause in which the brain shifts to a different type of attention deployment could be associated with something called the sensorimotor rhythm, or mu rhythm.

(various Eastern disciplines attempt to use mind-body integration to eventually generate more positive brain states and feelings of contentment and harmony)

The Sensorimotor Rhythm (SMR)

In The Head Trip, his lively account of a personal study of consciousness, Jeff Warren describes the research history of the SMR (the description is very interesting, so I'll quote him at some length):

The discovery of the SMR wave is one of the main threads in the history of neurofeedback. In 1965, a sleep researcher named Maurice Sterman, now neurobiology professor emeritus at UCLA, was studying the reflex that caused some animals to fall asleep instantly when they were stressed, an unusual finding made by Pavlov some years before. After training thirty cats to press a lever and get their reward (a ladleful of chicken broth), he introduced another element: a tone. Cats who pressed the lever when the tone sounded wouldn't get any chicken broth; they had to wait until the tone had finished sounding. This tension, Sterman thought, might cause them to fall asleep, a la Pavlov. The cats were wired into an EEG; Sterman prepared to inspect their dozing brain waves for cues.

Except that cats didn't fall asleep. Instead, they stayed stock-still---expectant, alert---waiting for the tone to end...To Sterman's surprise, this state of expectancy was accompanied by an EEG signal he had never seen before in this context: a very specific rhythmic spindle that repeated twelve to twenty times a second, with a peak around 12 to 15 hertz. It was concentrated over the cat's sensory-motor cortex... "It was fascinating," recalls Sterman. "We had never encountered this EEG rhythm before, and it didn't exist in the literature." He named it sensorimotor rhythm, or SMR.

Swirling around the behaviorist world at the time was a groundbreaking set of findings by the Yale experimental psychologist and learning theorist Neil Miller. To appreciate their significance, it's important to know the basics of how the nervous system works. The nervous system can be broadly divided into the central nervous system (the brain and spinal cord) and the peripheral nervous system (the body and organs). Within the peripheral system, the set of nerves that branch out into the body's muscles are called the somatic system, and the set of nerves that branch out into the organs are called the autonomic system. The former are under voluntary control---we can move our arm when we feel like it. The latter, it has long been assumed, are not---we cannot will our stomachs, for example, to speed up digestion.

Miller took a group of laboratory rats and planted electrodes in the pleasure centers of their brains. When the rats did what he wanted---for example, pressed a lever---they were rewarded with a little jolt. This was Operant Conditioning 101, the training of voluntary responses in the somatic system, the bread and butter of behavioral psychology. But then Miller did something potentially revolutionary. He decided to see if he could train the involuntary responses of the autonomic nervous system. Could rats learn to change their heart rates in return for a reward? The answer turned out to be yes. Within ninety minutes he had trained his rats to either lower or raise their heart rates by 20 percent, and he subsequently trained cats and dogs to regulate blood pressure, body temperature, and stomach acidity. By the late 1960s Miller had gone on to teach humans to lower their heart rates on demand, a technique that was especially helpful with a group of tachycardiacs (people with abnormally fast heart beats). Operant conditioning, long used to modify external behavior, was suddenly being used to modify internal behavior.

Inspired by Miller's work, Sterman decided to find out whether the same thing could be done with brain waves. He put his cats in the experimental chamber, but instead of pressing a lever, they had to produce SMR to get their chicken broth reward. Robbins writes, "Over the course of about a year, Sterman and his assistants trained ten cats an hour a day, three or four times a week, and the cats learned to produce 12 to 15 hertz at will." Thus neurofeedback (or the animal kingdom version, anyway) was born.

DoD Supercats

Apparently Sterman was still looking for practical applications and a deeper meaning in the SMR results when he received a grant from the Department of Defense to study the effects of inhaling monomethylhydrazine, a component of rocket fuel. The research was important because the inhalation of rocket fuel fumes induces nausea, severe seizures, and worse in test subjects; DoD wanted more information on thresholds in order to better design selection and safety measures for astronauts (the study took place in the late 1960s). In an experiment that would no doubt draw huge criticism from animal rights activists today, Sterman injected cats with rocket fuel in order to induce grand mal seizures.

Curiously, a small group of cats proved to be exceptionally seizure resistant. Sterman found that these special felines were all graduates of his earlier SMR-training experiment. As Warren puts it, "By learning to produce SMR, the cats had boosted their seizure thresholds, apparently strengthening the neural pathways in their sensory-motor cortex enough to ward off creeping electrical storm seizures."

SMR and the SEEKING System: Priming the Brain for Learning?


What was actually happening in the brains of these animals has taken Sterman close to forty years to work out, but today he has it down. When I spoke to him, he told me that the SMR rhythm was like the alpha of the motor system. It was the electrical idling that happened when there was reduced traffic between the thalamus---the brain's relay station---and the sensorimotor strip (though apparently it all starts with a part of the brain called the striatum, which controls background muscle tone and movement intention). When sensory input and motor output are reduced, the neurons along those pathways undergo transformation: they depolarize and then repolarize, and start sounding off in a weird burst-firing pattern that shows up as SMR waves on the EEG. It's an inhibition wave, similar---if not identical---to the spindle waves seen at sleep onset, which also reflect a decrease in sensory input and motor output. What's more, the particular neurophysiological conditions of spindling neurons are such that they maximize the possibility of long-term cell-wiring happening. Thus Sterman calls the spindle a kind of "soldering iron"; when it appears in the brain, it means conditions are exactly right for the fusing together of new and more robust circuits. Whatever was going on in the brain to produce the spindle then has a greater chance of being repeated. We have another name for this: learning.

In other words, the SMR condition appears to combine an "in the moment" alertness with an openness to new information (via working memory resources being available). It seems to be particularly designed for learning or preparing to use (hone) motor skills, and it is associated with moments of great anticipation. Is this SMR pause also linked to the SEEKING circuit that has been explored by Panksepp?

I think the two are deeply linked. Panksepp, in his descriptions of the SEEKING circuit, refers to a system by which a creature learns to develop IF-THEN knowledge between a given action and a given reward. He notes an "anticipatory eagerness" in test animals and how the correlated mental state could be pleasurable for the animal in order to reward exploratory behaviors (and counter the natural disinclination to explore because of the perils involved in stepping from the familiar and safe to the unknown).

Discussing why a behavioral bias (in contrast to a focus on the inner world of the animal) in psychology may have caused researchers to be slow to recognize the role that the SEEKING system plays in the interaction between an animal and its environment, Panksepp writes that:

Investigators seemed loathe to suggest the obvious---that self-stimulating animals appeared to be in a state of anticipatory eagerness. It was not clearly recognized that such a state might have positive incentive properties of its own...perhaps an apt analogy would be male sexual behavior, which consists of three phases: the initial appetitive behavior (some have called it "cruising and courting"), the actual copulatory behavior, and ejaculation/orgasm, the climactic terminal component, which may contain the most pleasurable aspects of the behavior sequences.

Panksepp's core argument is that the early work, which focused on simple behaviors and responses to rewards, masked an underlying neural architecture that had evolved to find seeking behavior pleasurable in and of itself (i.e., even in the absence of clearly linked rewards). This exploratory or SEEKING system is in turn correlated with the pleasure of learning something for its own sake.


...Why was there no clear conception that animals needed a brain system to seek rewards? Because behavioral psychologists were loathe to discuss any "inner causes." ...Since nature did not always provide the necessary resources for survival immediately at hand, each animal has a spontaneous tendency to explore and learn about its environment. When an animal has established a knowledge of its local terrain (probably through the development of cognitive maps), it can move about flexibly and efficiently find the things it needs. It also begins to spontaneously anticipate occurrences that are important in its quest for survival by using informative temporal or environmental cues.

Unfortunately, serious research into the sensorimotor rhythm was frustrated for years because New Age quacks got their enthusiastic hands on SMR and began associating it with a range of superhuman abilities, occasionally including levitation, telepathy, and astral projection. Groups that were purportedly involved in testing remote viewing capabilities for national-level intelligence collection also took an interest in the SMR spindle. The result has been that SMR drifted towards the dead-end parapsychology phenomenon side of the house and became something akin to the search for Atlantis.

More recently SMR seems to have made a comeback, as functional imaging technologies have developed renewed interest in brain states and associated emotions. The next post will discuss some interesting observations about SMR and intense travel experiences, particularly our first 48-72 hours in a foreign country.

*For those who were left dissatisfied with my layman description of this emotional cicuit, here is the direct line to the man himself. Panksepp summarizes the function of the SEEKING system as follows:

Investigators have generally created diverse names for this system. Originally I called it the foraging/expectancy system, while Jeffrey Gray called it the behavioral activation system; more recently, Richard Depue chose to call it the behavioral facilitation system, and most investigators working in the field are beginning to agree that it is a general "incentive or appetitive motivational system" that mediates "wanting" as opposed to "liking."

...This harmoniously operating neuroemotional system drives and energizes many mental complexities that humans experience as persistent feelings of interest, curiosity, sensation seeking, and, in the presence of a sufficiently complex cortex, the search for higher meaning. Although this brain state, like all other basic emotional states, is initially without intrinsic cognitive content, it gradually helps cement the perception of causal connections in the world and thereby creates ideas. As we will see, it appears to translate correlations into perceptions of causality, and it may be a major source of "confirmation bias," the tendency to selectively seek evidence for our hypotheses. The mental effects of psychostimulants such as cocaine and amphetamines that arouse the DA (dopamine) system provide a direct porthole into the feelings evoked by this emotional system. The affective state does not resemble the pleasurable feelings we normally experience when we indulge in various consummatory behaviors. Instead, it resembles the energization organisms apparently feel when they are anticipating rewards.

Traditionally, all motivated behaviors have been divided into appetitive and consummatory components. This distinction is premised on the recognition that one must not only seek out and approach the material resources needed for survival (except for oxygen, of course) but also interact with them in specific ways once they have been found: One must eat, drink, copulate, or carry the desired items home. The SEEKING system appears to control appetitive activation---the search, foraging, and investigatory activities---that all animals must exhibit before they are in a position to emit consummatory behaviors.