The Hard(wire) Problem: V

As a continuation of my last post on the subject...



Their model of self-collapse focuses on tubulin, a microtubule subunit protein. They claim that quantum states develop in the tubulins and, upon reaching a mass-time-energy threshold, objective reduction promptly occurs (Hammeroff & Penrose, 1996). Each instance of self-collapse equates to a conscious event. If this is true, then the classically-held view of consciousness by a vast majority of today’s neuroscientists, that of materialism, proves to be a valid argument. Neuroscientists, when and if, discussing consciousness, tend to favor the idea that consciousness stems from s complex cortical pathway. And while this pathway has neither been determined or understood, this theory implies that consciousness emerges from a physical substrate, a series of biochemical reactions. Hammeroff and Penrose are not the only ones to look to neural substrates as a means for understanding the role of quantum physics in the emergence of consciousness. Gustav Bernroider, through observations from his work with the K+ channel, suggests that behavior of this channel can only be understood at the quantum level. He suggests that a system of computational mapping exists between the quantum-entangled systems of K+ channel and O2 atoms of the binding pockets (on the channels). The ions that are destined to be expelled from the channel are proposed to encode information about the state of the O2 atoms (Bernroider, 2005).


As mentioned briefly before, neuroscience is a field dominated by biological naturalists who believe that consciousness can only arise in completely biological systems. This is similar to Searle’s earlier view that was attacked by Boden. Neuroscientists look to certain studies for their evidence. PVS (persistant vegetative state) patients are a popular model to look at with regards to consciousness. PVS involves loss of higher cerebral powers in the brain. However, the individual maintains their sleep-wake cycle and remains autonomically functional. This poses unique ethical challenges, especially when making the decision whether or not to withdraw life support (Levy, 2006). This also brings up the question of whether or not the individual is indeed themselves. If they do not experience consciousness, yet remain alive, are they little more than a plant? As for neural correlations, studying PVS patients seems to be critical. They have lost their consciousness; so what is different. Well, researchers have determined that PVS patients experience an impaired connectivity between the brainstem and the cortical areas; their cortical activity is therefore lower than the average individual’s (Levy, 2006). Neuroscientists are also currently using sedatives (Reeves et al., 2004), anesthetics (Ghoneim & Block, 1992), and hypnosis (Rainville et al., 2002) to attempt to tease apart different aspects of consciousness. And drugs, both illicit and prescription have been known to have varying effects on consciousness, pointing toward the idea that consciousness is an emergent property of biochemical reactions. An interesting study by Rodolpho Llinas (Llinas et al., 1998), entitled “The neuronal basis for consciousness,” claims that consciousness is the result of resonance in the thalamocortical areas of the brain. And of course, blindsight studies have been very popular when discussing proof of some sort of natural depth of consciousness (Holt, 1999).


Computer scientists also tend to hold physicalist views on consciousness. Functionalists like to define mental states in terms of causal roles. Therefore, any system that can instantiate the same pattern of causal roles should be able to give rise to the same mental states, including consciousness. In other words, if you can write complex computer programs that copy the brain states associated and correlated with consciousness, then theoretically one should be able to elicit the emergence of consciousness in a machine. Chalmers believes this: in properly designed computers, consciousness can be realized. Computer scientists have come up with several sets of criteria used to define consciousness in computer systems. Namely, Bernard Baars (Baars, 1988) and Igor Aleksander (Aleksander, 1994) hold two of the most popular and widely-used definition criterion. Baars’ criteria for consciousness are as follows: definition and context setting, adaptation and learning, editing, flagging and debugging, recruiting and control, prioritizing and access-control, decision-making and executive function, analogy forming, metacognitive and self-monitoring function, autoprogramming and self-maintenance function, and definitional and context-setting function (Baars, 1988). Aleksander uses 12 principles for what he calls Artificial Consciousness: the brain is a state machine, inner neuron partitioning, conscious and unconscious states, perceptual learning and memory, prediction, awareness of self, representation of meaning, learning utterances, learning language, will, instinct, and emotion display.

All of these criteria and forms of evidence for consciousness seem like they should be comprehensive enough to understand consciousness, yet we still do not know much more about how it emerges than we did decades ago. As artificial intelligence continues to progress within the context of Moore’s Law, we can expect to see some amazing feats of engineering and machines that will undoubtedly pass the Turing Test with ease. But, I raise the question again: will they ever be fully conscious on the same level as a human? I apologize for ending this series of posts on a non-distinct ground, but my opinions on the matter accurately reflect the state of the field of artificial intelligence at this point in time. My answer to the question: I do not know. However, if I were to predict one way that consciousness would emerge from an artificial system, I would say the system would have to be the perfect combination of biochemical reactions and computer science, of neural networks and algorithms, and of quantum mechanics and “spooky forces.”

The Hard(wire) Problem: IV

Recall that, according to Chalmers in The Hard(wire) Problem: II, what we are missing is an “extra ingredient,” that novel property that will explain how consciousness proceeds.  One such theory, the theory of quantum mechanics, attempts to account for the unique features of consciousness.   Almost all of modern physics is based on the quantum theory. 

 However, very few people actually question its implications.  Einstein was one of the few, and he was profoundly bothered by what he called “spooky forces” involved in quantum theory.  If quantum theory is correct, in Einstein’s mind, then it denies the existence of the real world.  An atom is only in one place because you observe it to be there, not necessarily because it physically exists there.  It is your act of looking that makes it visible to you.  In fact, that atom could exist in two, three, or many more places at once, until you look.  Conscious observation is what allows it to be found in actuality at that particular place you saw it (Rosenblum & Kuttner, 2006). 

Chalmers recognized the potential for a crucial connection between quantum theory and consciousness, “When there are two mysteries, it is tempting to suppose that they have a common source.  This temptation is magnified by the fact that the problems of quantum mechanics seem to be deeply tied to the notion of observership, crucially involving the relation between a subject’s experience and the rest of the world” (Rosenblum & Kuttner, 2006).  These are the two mysteries: the mystery of out there versus the mystery of in here.  But, according to some quantum theorists, out there and in here are fundamentally tied to one another in a state of universal consciousness.  Everything exists as wave functions in a state of entanglement, until an object is observed.  Stuart Hammeroff and Roger Penrose proposed the theory of objective reduction, OR, to address this.  According to OR, they “consider that consciousness occurs if an appropriately organized system is able to develop and maintain quantum coherent superposition until a specific "objective" criterion is reached; the coherent system then self-reduces (OR) (Hammeroff & Penrose, 1996).  This self-collapse gives rise to non-computability (qualia), the fundamental aspect of consciousness.  They go on to propose that OR is occurring actively in the microtubules of neurons (Hammeroff & Penrose, 1996).  

The Hard(wire) Problem: III

Before exploring the theories related to emergent properties of consciousness, however, we must first define artificial intelligence and look at some of the issues commonly associated with it.  Mathematician and philosopher Alan Turing was the first to raise the question, “can machines think?”  

Two important questions were raised and examined: 1.) What does it mean to be a machine?  2.)  How can we determine whether something thinks?    To determine whether something can think, Turing devised an intelligence test, now referred to as the Turing Test.  In the Turing Test, an interrogator presents a series of questions, to which both a machine and a human being answer.  If the machine can effectively fool the interrogator into thinking that it is indeed the human, then, in Turing’s argument, we must conclude that the machine is intelligent.  “Thinking” in the case of the Turing Test seems to be nothing more than “passing the test.”  

So is behaving like an intelligent human really equivalent to being intelligent?  Turing recognizes the fact that we cannot prove that the machine can ever experience qualitative consciousness like a human, but that this is precisely the same situation as trying to prove that another human being experiences qualitative consciousness.   All we have to go by, in either situation, is behavior; it is the only information readily available to us as the observer.  We can therefore only be certain of our own intelligence.  This seems to line up well with Dennett’s argument in “Quining Qualia.” 

John Searle, in his paper, “Minds, Brains, and Programs,” attacks what he calls Strong AI, or the production of intelligent machines, with the theory that achieving intelligence is impossible in computer systems due to their very nature.  He rejects the idea that a computer that can pass the Turing Test has cognitive states and that programs can thereby explain human cognition.  He uses the Chinese Room imaginary machine to clarify his views. 

 The example consists of him sitting in a room and manipulating sets of Chinese symbols for someone outside the room.  He receives sets of instructions, in English, for manipulating the symbols, yet still has no real understanding of the Chinese.  After a while, he becomes so good at manipulating the symbols that the outsider can no longer distinguish him from a native Chinese speaker.  However, he still cannot “recognize Chinese writing as Chinese distinct from, say Japanese writing or meaningless squiggles” (Searle, 1980).  He does not understand Chinese.  This, Searle argues, describes the distinction between a Turing computer and a cognitive being.  Searle later claims that intentionality will only arise in biological systems, an implication that does not bode well for physicalist, strong AI computer scientists.  

Margaret Boden, however, argues that Searle’s claims are mistaken.  He does not have any real understanding, nor does anybody else, she says, how intentionality would derive from the brain, as Searle claims later in his paper.  Boden thinks that Searle’s claim that intentionality can only arise in a biological system is incomplete, precisely because we have so little understanding of intentionality at all.  What exactly do scientists think about intentionality and the emergent properties associated with consciousness?  

The Hard(wire) Problem: II

This next series of posts will be organized as follows: first, I will take a brief look into the views of consciousness held by prominent mind theorists and philosophers; I will next explore what it means to be artificially intelligent; then I’ll move onto what physics, neuroscience, and computer science have to tell us about the possibility of a conscious machine.  I will conclude with the important question: is it possible?

So what is it like to be a bat?  This question, asked by Thomas Nagel, helps frame our reference point.  In his paper of the same name, Nagel rejects reductionism, arguing that we can’t reduce our descriptions of the mental experience to pure neurological terms.  Mental states have a qualitative character, something it is like to be.  He refers to this as the subjective character of experience.  In terms of the bat, if we assume that the bat has conscious experiences, then we can put ourselves in the bat’s position and therefore assume what it must be like to be the bat.  However, we cannot possibly know what the exact same situation is like for the bat itself.  It may be completely different because, as Nagel argues, the central characteristic of the mind is consciousness, and we cannot possibly know exactly what any other conscious being is experiencing.  In Nagel’s view, we cannot rationally reduce conscious experience to physical properties or neural substrates or pathways in the brain. 

Nagel’s description of qualitative consciousness is vague at best.  To address this issue, Frank Jackson wrote the paper “Epiphenomenal Qualia.”  Qualia, as defined by Jackson, are “certain features of the bodily sensations especially, but also of certain perceptual experiences, which no amount of purely physical information includes," that is, qualia cannot be described in a purely physical vocabulary.  Examples of quale include sensations and perceptual experiences, things such as “the hurtfulness of pains, itchiness of itches … experience of smelling a rose."  If qualia exist, then, in Jackson’s view, materialism does not.  To put it bluntly, he states, “Nothing you could tell of a purely physical sort captures the smell of a rose, for instance.  Therefore, physicalism is false."  If Jackson is correct, this may present an important issue for consciousness in the machine.  As we will see, most neuroscientists and computer scientists are physicalists. 

But do qualia hold up under close examination?  Daniel Dennett doesn’t think so, and he uses his paper, “Quining Qualia,” to do just what the title implies, resolutely deny qualia’s testability, and therefore fundamentally question the utility of qualia in any argument.  The main issue Dennett takes with qualia is their nature: they are private, ineffable, incommunicable, irreducible.    In principal, it is impossible to know exactly what another conscious being experiences, and therefore the question of whether a certain experience exists is senseless.  The lack of verifiable criterion is important in understanding (or not understanding) qualia.  It is what makes two individuals’ definitions of the same thing different, and therefore meaningless.  In terms of neural activity, Dennett still holds the view that there is no evidence for, and will never be evidence, that can infallibly correlate a certain neural event or sequence of activity with a certain experience.  

David Chalmers, former Director of the Center for Consciousness Studies at the University of Arizona and degree holder in mathematics and computer science, begs to differ with Dennett.  He believes that the very ineffable qualitative experiences that Dennett rejects as fictions are of utmost importance in understanding consciousness.  He says, “It is widely agreed that experience arises from a physical basis, but we have no good explanation of why and how it arises.  Why should physical processing give rise to a rich inner life at all?  It seems objectively unreasonable that it should, and yet it does."  And yet it does.  This is a ray of hope for AI scientists.  Somehow, amidst the precisely controlled milieu of a computer system, consciousness, that indescribable and unpredictable property, may emerge.      

The Hard(wire) Problem

Conscious experience: the most difficult problem to address in the science of the mind.  As David Chalmers puts it, “There is nothing that we know more intimately than conscious experience, but there is nothing that is harder to explain.”  Philosophers have been taking stabs at an explanation of the “hard problem” of conscious experience for thousands of years, yet the problem persists.  

And now, at the dawn of the “age of intelligence,” we are faced with a new and exciting, but potentially troubling issue: as our machines get more and more intelligent, is there any chance that they may become conscious?  They can already do so many things at levels that are currently humanly impossible; could a conscious race of machines make human life inconsequential?  A favorite topic of SciFi authors and film directors for decades, AI takeover is now quickly transitioning from a distant fantasy to a very real, very tangible possibility. 

But will it ever be possible?  Is it conceivable for a machine to become a conscious being?  Some think it’s a laughable concept, one deserving of little attention or thought; others are devoting their lives to trying to make it happen.  Who’s right?  Will all efforts at AI consciousness be in vain?  I will be exploring these questions through a new lens, looking beyond philosophy.  If AI consciousness is ever to be, it will arrive as the sublime amalgamation of quantum and neural sciences, heavily-influenced by computer science: a biological computer.

Food as Drug: A Cultural & Medical History of Food Addiction & Compulsive Overeating PART III

The third post in this series is a continuation of the second, in that we will continue looking at the psychology and neuroscience behind food addiction.  Post IV will begin looking at the cultural aspects related to food addiction and compulsive overeating, so stay tuned.

Homeostatic and hedonic hungers, while fundamentally different in motivation, are both evolutionary important.  Both motivations would’ve helped drive an individual to eat plenty of calories in order to satisfy the body’s energy needs in times of food scarcity or uncertainty.  Thus, humans either learned, or innately possessed, the ability to eat past satiety.  Hypothetically, if a hunter-gatherer were to stop eating at the first sign of satiety then experience a prolonged period of time between their next meal, say the hunting was slow or they were traveling through an area with little vegetation, they would put their body at risk for usurping its energy stores.  To protect against this, they would use hedonic hunger to override homeostatic hunger.     We still possess this ability today.  Though because we live in a time of food abundance, developing the habit of continually eating past our homeostatic set-points has proven to be severely detrimental to health and the main cause of obesity.  The theory of ‘motivating operations’ (Tapper, 2005) focuses on explaining the motivations for food seeking.  However, they completely ignore any aspect of overeating.  They claim that food seeking will increase and hedonic enjoyment of food will be enhanced with deprivation.  The reverse implies that with satiety, seeking behaviors and enjoyment of food will decrease.  This does not account for the phenomenon that is binge eating.  However, ‘motivating operations’ remains somewhat in line with the incentive sensitization model in that they both involve a decrease in food liking during overeating.   When wanting increases due to sensitization, liking decreases. 

The µ-opioid system plays a key role in hedonics.  In a study using highly-palatable foods (high sugar and fat), opioid administration to sated rats resulted in a stronger desire for food than seen in rats who had been deprived of food (Hayward & Low, 2005).  Opioids are thought to increase the hedonic properties of food.  More evidence comes from a study where administration of opioids in the nucleus accumbens of rats induced episodes of binge eating on fat (Hayward & Low, 2005).  Taken alone, a pure fat foodstuff, such as Crisco, has very little rewarding taste properties unless it is mixed with another highly-palatable food such as sugar.  Therefore this study serves as a good indicator of the role of opioids in increasing a food’s hedonic qualities, suggesting that individuals with food addiction may be hypersensitive to opioids in the brain or have an overactive reward system.  Sugar is thought to act in the brain similarly to an opioid.  Referring back to the aforementioned Avena et al. (2008) study, recall that they found that rodents on a high sugar chow diet exhibit addictive-like behaviors as the researchers increased daily sugar intake over a period of 28 days.  The rats also exhibit opioid-like withdrawal symptoms when given the opioid antagonist naloxone (3 mg/kg).  Their symptoms included anxiety, teeth chattering, tremor, head shakes, and a drop in body temperature (Avena et al, 2008) suggesting that natural rewards such as sugar act on similar neural substrates as illicit drugs.   Hopefully now the correlation between compulsive overeating and other addiction disorders is becoming apparent.    

Individuals with food addiction undoubtedly exhibit certain behaviors and personality traits that are strikingly similar to those of drug addicts.   The main difference lies in the fact that food addiction is more accurately referred to as a ‘behavioral addiction:” one involving abuse of natural rewards (Davis et al, 2009).  Drugs of addiction also act directly on the brain.  Food acts indirectly, through the gut.  However, gut peptides have strong connections to the dopaminergic (DA) system (Dagher, 2009), a system closely-linked to liking and wanting of illicit drugs.  Eating, unlike drug-taking, is intrinsically required for human survival.  And just as higher doses of drugs result in higher potential for addiction, we can see that larger ‘meals,’ or more accurately, binges, can also result in high potential for addiction.  Grigson (2002) asserts that foods, like drugs, have the ability to alter brain mechanisms in ways that contribute to their increasingly compulsive use.  In their paper on the neurobiology of eating and drug abuse, Corwin & Hajnal (2005) outline four things that must be considered when operationally defining non-homeostatic appetitive behavior: quantity consumed, quality or type consumed, context in which the behavior occurs, and the specific kind of behavior that is directed toward obtaining and consuming the commodity of interest.  

These aspects are to be used in for defining all types of non-homeostatic behavior, including compulsive overeating, not just drug addiction behavior.  It is normal to overeat on occasion.  Such overeating can be effectively regulated by the body’s systems because they are prepared to work harder at certain times than others.  This type of overeating is referred to as compensatory.  However, when it becomes compulsive, it renders itself dysfunctional because the human body is maladapted to deal with chronic stress to the degree that excessive sugar and fat intake will induce.  Long-term health issues follow.  Parallels can be made to drug taking in this regard as well.  Recreational use, with adequate detoxification periods between use episodes, does not result in chronic negative effects on physical and mental health.  However, when use escalates to abuse, extremely negative effects follow. 

The neuro-anatomical substrates associated with compulsive overeating are the same as those implicated in all appetitive behaviors, including drug taking.  The main regions involved in appetitive behavior are the amygdala, hippocampus, orbitofrontal cortex, insula, and striatum (Dagher, 2009).  When considered as a pathway, one entity, these substrates are all implicated in the following: learning about (food) rewards, setting the incentive value of stimuli in the environment, budgeting attention and efforts toward (food) rewards, and integrating homeostatic information about energy stores and gut contents with information about the outside world (availability of food)(Dagher, 2009).  These substrates have been found to respond equally to food cues and drugs cues (Dagher, 2009) as well as contain prominent DA projections.  When a blockade was applied to this DA pathway, all rodent responding for drugs and food was abolished (Wise et al, 1978).  And lesions to these areas impair feeding behavior (Wise et al, 1978).  In order to fully understand eating behavior, one must understand the interaction between the gut (enteric nervous system) and the central nervous system.  The key players in these interactions are hormones, which project to the hypothalamus.  

Food as Drug: A Cultural & Medical History of Food Addiction & Compulsive Overeating PART II

In this second post of the series, I want to take a closer look at the neural and psychological causes and underpinnings of food addiction.  

Because the obese condition can be reached several ways, and because not all instances of excessive food intake can be regarded as dysfunctional, it would not be suitable to group these two entities into a subclass of addiction.  Addiction requires compulsive action and lasting changes on the neural level.  Therefore, as a distinct phenotype of obese individuals, compulsive overeaters may very well be classified as “addicts.” 

The dysfunctional behavior and neural maladaptations of compulsive overeaters adhere to DSM-IV criteria and parallel drug-addicted patients sufficiently enough to implicate substance addiction as playing the key role in their non-homeostatic physical and mental states. Food can be addictive.  Just as some individuals can recreationally use drugs, many people can casually/passively eat to meet their caloric requirements.  However, similar to the compulsive drug-taking and seeking behavior seen in addicts, food inspires compulsive behaviors in a distinct class of individuals, consciously and unconsciously driving their thoughts and actions to the point where homeostasis is no longer an issue: compulsive overeating is an addiction.   

               

The DSM-IV defines substance-dependence (addiction) as exhibiting three or more of the following in regards to a substance of abuse, which in this case, is food: tolerance, withdrawal, consuming large amounts over a long period of time, having unsuccessful efforts to stop use or to cut down, time spent in obtaining, thinking about, and consuming the substance replaces social, occupational, and recreational activities, and lastly, exhibiting continued use despite adverse consequences.  With this in mind, we can relatively easily classify compulsive overeating as a substance-dependence disorder, or addiction. 

In empirical research, compulsive overeaters display characteristics of developing tolerance; they’ve been found to progressively require more and more food to achieve the desired “drugged” effect (e.g. “the sugar high”) as time goes on (Davis & Carter, 2009).  Much of the human evidence of this comes from clinical anecdotes given by the patients themselves.  Picot and Linfield (2003) also found that higher body weight correlated with the frequency and severity of bingeing episodes.  This may indicate that as level of obesity increases, the disorder worsens.  More indirect evidence of tolerance can be found in animal studies.  Avena et al. (2008) found that rodents on a high sugar chow diet exhibit addictive-like behaviors, increasing daily sugar intake over a period of 28 days.  The rats also exhibit opioid-like withdrawal symptoms when given the opioid antagonist naloxone (3 mg/kg).  Symptoms include anxiety, teeth chattering, tremor, head shakes, and a drop in body temperature (Avena et al, 2008) suggesting that natural rewards such as sugar act on similar neural substrates as illicit drugs.   And with all of the warnings from medical practitioners as well as nutritional education in the public school systems from a young age, it would be absolutely inappropriate to assume that compulsive overeaters were not aware of their behaviors’ adverse affects on their health.  They continue compulsive overeating despite awareness of how detrimental it is. 

              

  Donald Hebb describes eating as being a learned behavior that is reinforcing because it reverses unpleasant bodily signals and comes to be associated with environmental cues which can trigger craving (Hebb, 1949).  Food is considered a natural reward.  Food, as a substance of abuse, becomes a rather complicated matter because, unlike illicit drugs, food is intrinsically necessary for survival.  However, in excess, it can have such adverse effects as to lead to diabetes, heart disease, and consequently, premature death.   When viewed through the scope of evolution, food cravings can be seen as a necessary biological mechanism for survival in unpredictable environments.  Early hunter-gatherer societies never knew how long it would be before they found their next meal.  It was not uncommon to go for days without food, or with very little food.  In these cases, the human body has developed in such a way that it will store fat for energy, especially after large meals.  When food enters the body and blood glucose levels rise, insulin is released and fat is no longer used as an energy source.  The body preserves it for later use.  It instead utilizes the energy from the incoming calories, carbohydrate being the most readily consumed.   This “fat-preservation” mechanism is what allowed our ancestors to survive for long periods of time between meals.  However, in our current nutritional condition, food is readily available.  Not only that, it is also calorically dense, with most processed varieties being high in sugar as well.  The steady influx of sugar into the human body keeps blood glucose levels high, never giving it the chance to use fat stores as fuel.  Instead, excess fat is stored and over time accumulates until the individual is in the obese state.  Many individuals also become insulin resistant, resulting in Type II Diabetes. 

                

So what is the difference between liking and wanting food?  And why can making such a distinction help develop a better understanding of compulsive overeating as an addiction disorder? First, to differentiate between the two, liking of food refers to the pleasure one gets from eating the food.  Wanting food refers to appetite.  Excessive wanting leads to compulsion.  There is no doubt that food addicts experience compulsive food-seeking/consuming behavior.  But why do they do so, when others don’t?  To answer this question, we look to Robinson and Berridge (2000) and their incentive-sensitization theory.  According to sensitization theory, the drug/food will have an increased effect on the reward system following repeated doses/eating.  Individuals with easily sensitized brains will therefore be more likely to develop an addiction.  The critical prediction made by incentive-sensitization is that the brains of addicted individuals will no doubt contain a region or pathway that has been sensitized by drugs, or in our case food.  To add to it, sensitization is dose dependent, meaning the higher the dose, the more pronounced the sensitization.  Unhealthy meals, such as a Super-Sized Value Meal, and binge episodes may constitute consuming thousands of calories, definitely a large amount of food.  Therefore, according to this theory, sensitization would be greatly increased in over eaters.  The main point here is that when sensitized, the food/drug ‘wanting’ produces compulsive                                                                                                             patterns of seeking-behavior.  Herein lies the critical connection.  Certain individuals are more easily sensitized than others; as the doses increase, sensitization increases, creating a heightened wanting for food; this wanting thus manifests in compulsive food-seeking behavior: addiction.  They outline two different types of wanting: implicit and explicit wanting (Finlayson et al, 2003).  These involve separate processes but they complement each other to contribute to food preference.  Implicit wanting is how hard an individual is willing to work for food.  This is the independent risk factor for overconsumption.  The harder someone is willing to work to get the food, the more likely they are to eat too much of it.  Food has a heightened value to them.  Explicit wanting refers to an individual’s desire to eat a specific kind of food.  Preference for high fat, high sugar foods would reflect explicit wanting.

Incentive-sensitization is one of several popular theories for why people compulsively over eat.  It is important to realize that the processes leading to food consumption are not all explicit.    Implicit processes play just as much of a role, if not more, in food seeking behavior.  With this in mind, is eating necessarily under voluntary control?  We usually see it as such because of utilization of musculature to obtain and consume food.   We can perceive our outstretched arm as our hand reaches for the food.  But knowing what we do about wanting, the importance of implicit wanting cannot be overlooked, because without it, explicit wanting would not matter.  If the individual is not willing to work to get food, say get off the coach, then of course they will not care about the type of food they eat.  So what drives implicit wanting?  On the surface, we might say hunger, because it does.  However, this doesn’t account for why someone will continue to eat past feeling ‘full.’  There must be a relationship between the hedonics of food and bodily homeostasis, with hedonics having the ability to override the innate desire for a homeostatic internal environment.  Our knowledge of liking and wanting in food-related behaviors is relatively limited.  So, in order to strengthen our understanding, it helps to draw upon separate theoretical models for guidance.  

Food as Drug: A Cultural & Medical History of Food Addiction & Compulsive Overeating PART I

Over the coming days, I will devote several posts to this topic.  I think it is incredibly important, with special regards to a large portion of the American population.  We are at a point where food addiction is arguably the most common, widespread cultural and medical problem this country has ever experienced.  Obesity numbers continue to climb through the roof.  I saw a statistic today that claimed the percent of American men with a BMI of 30 or above is a staggering 44.2%, while that of women is an even worse 48.3% (Click HERE to see the study).  We've got a problem on our hands, people.  And I want to argue that food addiction and the subsequent compulsive overeating are the main culprits in this debacle.

   Excessive food consumption is a relatively common phenomenon in Western society.  Much of it appears to occur seasonally, especially around traditional and festive holidays or family gatherings.  And with the ease-of-access to highly-processed, highly-palatable foods in the supermarket and on the street corner, excessive caloric intake has become habitual for many Westerners and has seemingly led to what many health professionals refer to as the “Obesity Epidemic.”  Some have made the arguments of high fat, sugary, or salty foods as being “addictive” (Cocores & Gold, 2009) or having “addictive qualities.”  However to make the blanket statement that obesity in general is an addiction would clearly be inappropriate.  Obesity is merely a symptom, the result of an addiction.  An addiction, as defined by Webster’s New World Medical Dictionary, is “a chronic relapsing condition characterized by compulsive drug-seeking and abuse and by long-lasting chemical changes in the brain.” 

The key word we want to focus on for now is compulsive.  Until recently, the word “addiction” has been solely used as a descriptor for drug-abuse.  In recent decades however, medical professionals and the general public alike have both begun questioning this and proposing theories regarding the addictive properties of food on a widespread level.  It is important to note that not every case of obesity involves compulsion.  Davis and Carter (2009) argue that overeating for many is a passive event, occurring “almost without awareness”.   It has become habitual, manifesting itself in the forms of snacking and frequent consumption of large portion sizes.  This near-lack –of- awareness is different than a compulsive drive.  These individuals eat large amounts out of habit.  Lack of proper nutritional education may also play a small role.  Overly large serving sizes are served at nearly every fast food restaurant and every diner in America.  The phrase “get more for your money” is hardwired into the consumer mindset, and has become the motivator for a cut-throat food-service industry, to the detriment of consumer health.

 However, for many, the consumption of certain foods does involve compulsion.  Cravings drive choice.  Very large populations of Americans are dissatisfied with their bodies and their nutritional choices on a day-to-day basis.  They make nutritional choices that they know are not optimal and frequently overeat.  The diet industry has exploded over recent decades as obesity numbers continue to climb.  Obese sufferers of food addiction have been shown to exhibit a compulsive drive to excessively overeat: most namely, eating even when uncomfortably full and even when doing so will harm them physically and/or psychologically.  For example, in a study done by Cassin and von Ranson (2007), 94% of their adult samples classified themselves as “food addicts” or “compulsive overeaters,” meeting DSM-IV substance-dependence disorder criteria.

 But why do food addicts consume more food, and poorer quality food, than their body requires to function at an optimal level?  Is there some inherent quality to modern food that stimulates pleasure-related cortical pathways in some people more than others?  Is food really addictive?  And how did we get here with regards to the Obesity Epidemic?  What cultural movements and modern historical developments caused such a drastic rise in American obesity in such a short period of time?

This and subsequent posts will lay out an exhaustive argument for why compulsive overeating is in fact an addiction, caused by a complex interplay of factors including cultural stressors, lack of nutritional quality in modern food, and human neural maladaptational responses to consumption of these foods.  My argument will draw upon myriad medical, historical, and cultural literature for support, and will hopefully shed some light onto the dire condition within which a large percentage of the American population now resides: a condition that, I argue, has contributed greatly to the drastic rise in obesity in the United States over the past few decades.  Food addiction and compulsive overeating are not the sole cause for obesity, but they are the major player.  

TechCrunch: Good Read

We're in a bubble and it's not the internet. It's higher education.

by Peter Thiel.  

Quotable

“I must create a system or be enslaved by another mans; I will not reason and compare: my business is to create.” - William Blake.