Addiction

Addiction is a compulsion to repeat a behaviour regardless of its consequences. A person who is addicted is sometimes called an addict.

There is a lack of consensus as to what may properly be termed 'addiction.' Some within the medical community maintain a rigid definition of addiction and contend that the term is only applicable to a process of escalating drug or alcohol use as a result of repeated exposure. However, addiction is often applied to compulsive behaviors other than drug use, such as overeating or gambling. In all cases, the term addiction describes a chronic pattern of behaviour that continues despite the direct or indirect adverse consequences that result from engaging in the behavior. It is quite common for an addict to express the desire to stop the behaviour, but find himself or herself unable to cease.

Addiction is often characterized by a craving for more of the drug or behavior, increased physiological tolerance to exposure, and withdrawal symptoms in the absence of the stimulus. Many drugs and behaviours that provide either pleasure or relief from pain pose a risk of addiction or dependency.

Terminology and usage
The medical community now makes a careful theoretical distinction between physical dependence (characterized by symptoms of withdrawal) and psychological addiction (or simply addiction). Addiction is now narrowly defined as "uncontrolled, compulsive use despite harm"; if there is no harm being suffered by, or damage done to, the patient or another party, then clinically it may be considered compulsive, but within this narrow definition it is not categorized as "addiction". In practice, however, the two kinds of addiction are not always easy to distinguish. Addictions often have both physical and psychological components.

There is also a lesser known situation called pseudo-addiction, where a patient will exhibit drug-seeking behaviour reminiscent of psychological addiction, however in this case, the patients tend to have genuine pain or other symptoms that have been undertreated. Unlike true psychological addiction, however, these behaviours tend to stop as soon as their pain is adequately treated. The term "dry drunk" is sometimes attached to patterns of behavior that persist after an object of dependence and/or misuse has been removed from daily living routines. This type of behaviour is fairly common in early recovery for those recovering from substance misuse.

The obsolete term physical addiction is deprecated, because of its connotations. In modern pain management with opioids: physical dependence is nearly universal but addiction is rare. Some of the highly addictive drugs (hard drugs), such as cocaine, induce relatively little physical dependence.

Not all doctors do agree on what addiction or dependency is*, particularly because traditionally, addiction has been defined as being possible only to a psychoactive substance (for example alcohol, tobacco, or drugs), which is ingested, crosses the blood-brain barrier, and alters the natural chemical behaviour of the brain temporarily. Many people, both psychology professionals and laypersons, now feel that there should be accommodation made to include psychological dependency on such things as gambling, food, sex, pornography, computers, work, and shopping / spending. However, these are things or tasks which, when used or performed, cannot cross the blood-brain barrier and hence, do not fit into the traditional view of addiction. Symptoms mimicking withdrawal may occur with abatement of such behaviours; however, it is said by those who adhere to a traditionalist view that these withdrawal-like symptoms are not strictly reflective of an addiction, but rather of a behavioural disorder. In spite of traditionalist protests and warnings that overextension of definitions may cause the wrong treatment to be used (thus failing the person with the behavioural problem), popular media, and some members of the field, do represent the aforementioned behavioural examples as addictions.
 * note: the Diagnostic Statistical Manual (DSM IVR) specifically spells out criteria to define abuse and dependence conditions.

Physical dependency
Physical dependency on a substance is defined by the appearance of characteristic withdrawal symptoms when the drug is suddenly discontinued. While opioids, benzodiazepines, barbiturates, alcohol and nicotine are all well known for their ability to induce physical dependence, other drugs share this property that are not considered addictive: cortisone, beta-blockers and most antidepressants are examples. So while physical dependency can be a major factor in the psychology of addiction, the primary attribute of an addictive drug is its ability to induce euphoria while causing harm.

Some drugs induce physical dependence or physiological tolerance - but not addiction - for example many laxatives, which are not psychoactive; nasal decongestants, which can cause rebound congestion if used for more than a few days in a row; and some antidepressants, most notably Effexor and Paxil, as they have quite short half-lives, so stopping them abruptly causes a more rapid change in the neurotransmitter balance in the brain than many other antidepressants. Many non-addictive prescription drugs should not be suddenly stopped, so a doctor should be consulted before abruptly discontinuing them.

The speed with which a given individual becomes addicted to various substances varies with the substance, the frequency of use, the means of ingestion, and the individual. Some alcoholics report they exhibited alcoholic tendencies from the moment of first intoxication, while most people can drink socially without ever becoming addicted. Because of this variation, some people hypothesise that physical dependency and addiction are in large part genetically moderated. Nicotine is one of the most addictive psychoactive substances: although 35 million smokers make an attempt to quit every year, less than 7% achieve even one year of abstinence.*

While eating disorders, like other behavioral addictions, are usually considered primarily psychological disorders, they are sometimes treated as addictions, especially if they include elements of addictive behavior. Sufferers may experience withdrawal or withdrawal-like symptoms if they alter their diet suddenly. This suggests that some common food substances, especially chocolate, sugar, salt and white flour may have the potential for addiction. In addition, frequent overeating can also be considered an addiction.


 * From the NIDA research report on nicotine addiction.

Psychological addiction
Psychological addictions are a dependency of the mind, and lead to psychological withdrawal symptoms. Addictions can theoretically form for any rewarding behavior, or as a habitual means to avoid undesired activity, but typically they only do so to a clinical level in individuals who have emotional, social, or psychological dysfunctions, taking the place of normal positive stimuli not otherwise attained (see Rat Park).

Addiction and drug control legislation
Most countries have legislation which brings various drugs and drug-like substances under the control of licensing systems. Typically this legislation covers any or all of the opiates, cannabinoids, cocaine, barbiturates, hallucinogens and a variety of more modern synthetic drugs, and unlicensed production, supply or possession is a criminal offence.

Usually, however, drug classification under such legislation is not related simply to addictiveness. The substances covered often have very different addictive properties. Some are highly prone to cause physical dependency, whilst others rarely cause any form of compulsive need whatsoever.

Also, although the legislation may be justifiable on moral or public health grounds, it can make addiction or dependency a much more serious issue for the individual: reliable supplies of a drug become difficult to secure, and the individual becomes vulnerable to both criminal abuse and legal punishment.

Methods of care
Early editions of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM) described addiction as a physical dependency to a substance that resulted in withdrawal symptoms in its absence. Recent editions, including DSM-IV, have moved toward a diagnostic instrument that classifies such conditions as dependency, rather than addiction. The American Society of Addiction Medicine recommends treatment for people with chemical dependency based on patient placement criteria (currently listed in PPC-2), which attempt to match levels of care according to clinical assessments in six areas, including:
 * Acute intoxication and/or withdrawal potential
 * Biomedical conditions or complications
 * Emotional/behavioral conditions or complications
 * Treatment acceptance/resistance
 * Relapse potential
 * Recovery environment

Some medical systems, including those of at least 15 states of the United States, refer to an Addiction Severity Index to assess the severity of problems related to substance use. The index assesses problems in six areas: medical, employment/support, alcohol and other drug use, legal, family/social, and psychiatric.

While addiction or dependency is related to seemingly uncontrollable urges, and may have roots in genetic predisposition, treatment of dependency is always classified as behavioral medicine. Early treatment of acute withdrawal often includes medical detoxification, which can include doses of anxiolytics to reduce symptoms of withdrawal. In chronic opiate addiction, a surrogate drug such as methadone is sometimes offered as a form of opiate replacement therapy. But treatment approaches universally focus on the individual's ultimate choice to pursue an alternate course of action.

Therapists often classify patients with chemical dependencies as either interested or not interested in changing. Treatments usually involve planning for specific ways to avoid the addictive stimulus, and therapeutic interventions intended to help a client learn healthier ways to find satisfaction. Clinical leaders in recent years have attempted to tailor intervention approaches to specific influences that effect addictive behavior, using therapeutic interviews in an effort to discover factors that led a person to embrace unhealthy, addictive sources of pleasure or relief from pain.

Diverse explanations
Several explanations (or "models") have been presented to explain addiction:


 * The moral model states that addictions are the result of human weakness, and are defects of character. Those who advance this model do not accept that there is any biological basis for addiction. They often have scant sympathy for people with serious addictions, believing either that a person with greater moral strength could have the force of will to break an addiction, or that the addict demonstrated a great moral failure in the first place by starting the addiction. The moral model is widely applied to dependency on illegal substances, perhaps purely for social or political reasons, but is no longer widely considered to have any therapeutic value. Elements of the moral model, especially a focus on individual choices, have found enduring roles in other approaches to the treatment of dependencies.


 * The opponent-process model generated by Richard Soloman states that for every psychological event A will be followed by its opposite psychological event B. For example, the pleasure one experiences from heroin is followed by an opponent process of withdrawal, or the terror of jumping out of an airplane is rewarded with intense pleasure when the parachute opens. This model is related to the opponent process color theory.  If you look at the color red then quickly look at a gray area you will see green.  There are many examples of opponent processes in the nervous system including taste, motor movement, touch, vision, and hearing. Opponent-processes occurring at the sensory level may translate "down-stream" into addictive or habit-forming behavior.


 * The disease model holds that addiction is an illness, and comes about as a result of the impairment of healthy neurochemical or behavioral processes. While there is some dispute among clinicians as to the reliability of this model, it is widely employed in therapeutic settings. Most treatment approaches involve recognition that dependencies are behavioral dysfunctions, and thus involve some element of physical or mental disease.


 * The genetic model posits a genetic predisposition to certain behaviors. It is frequently noted that certain addictions "run in the family," and while researchers continue to explore the extent of genetic influence, there is strong evidence that genetic predisposition is often a factor in dependency. Researchers have had difficulty assessing differences, however, between social causes of dependency learned in family settings and genetic factors related to heredity.


 * The cultural model recognizes that the influence of culture is a strong determinant of whether or not individuals fall prey to certain addictions. For example, alcoholism is rare among Saudi Arabians, where obtaining alcohol is difficult and using alcohol is prohibited. In North America, on the other hand, the incidence of gambling addictions soared in the last two decades of the 20th century, mirroring the growth of the gaming industry. Half of all patients diagnosed as alcoholic are born into families where alcohol is used heavily, suggesting that familiar influence, genetic factors, or more likely both, play a role in the development of addiction.


 * The blended model attempts to consider elements of all other models in developing a therapeutic approach to dependency. It holds that the mechanism of dependency is different for different individuals, and that each case must be considered on its own merits.


 * The habit model proposed by Thomas Szasz questions the very concept of "addiction." He argues that addiction is a metaphor, and that the only reason to make the distinction between habit and addiction "is to persecute somebody." (Szasz, 1973)


 * The genetic neurobiological model called Hypoism. Read about the science behind this and its implications at http://www.nvo.com/hypoism. The scientific argument is at: http://www.nvo.com/hypoism/hypoismhypothesis/

Neurobiological basis
The development of addiction is thought to involve a simultaneous process of 1) increased focus on and engagement in a particular behavior and 2) the attenuation or "shutting down" of other behaviors. For example, animals allowed the unlimited ability to self-administer psychoactive drugs will show such a strong preference that they will forgo food, sleep, and sex for continued access. The neuro-anatomical correlate of this that the brain regions involved in driving goal-directed behavior grow increasingly selective for particular motivating stimuli and rewards, to the point that the brain regions involved in the inhibition of behavior can no longer effectively send "stop" signals. A good analogy is to imagine flooring the gas pedal in a car with very bad brakes. In this case, the limbic system is thought to be the major "driving force" and the orbitofrontal cortex is the substrate of the top-down inhibition.

A specific portion of the limbic circuit known as the mesolimbic dopaminergic system is hypothesized to play an important role in translation of motivation to motor behavior- and reward-related learning in particular. It is typically defined as the ventral tegmental area (VTA), the nucleus accumbens, and the bundle of dopamine-containing fibres that connecting them. This system is commonly implicated in the seeking out and consumption of rewarding stimuli or events, such as sweet-tasting foods or sexual interaction. However, ita importance to addiction research goes beyond its role in "natural" motivation: while the specific site or mechanism of action may differ, all known drugs of abuse have the common effect in that they elevate the level of dopamine in the nucleus accumbens. This may happen directly, such as through blockade of the dopamine re-uptake mechanism (see cocaine). It may also happen indirectly, such as through stimulation of the dopamine-containing neurons of the VTA that synapse onto neurons in the accumbens (see opiates). The euphoric effects of drugs of abuse are thought to be a direct result of the acute increase in accumbal dopamine.

The human body has a natural tendency to maintain homeostasis, and the central nervous system is no exception. Chronic elevation of dopamine will result in a decrease in the number of dopamine receptors available in a process known as downregulation. The decreased number of receptors changes the permeability of the cell membrane located post-synaptically, such that the post-synaptic neuron is less excitable- ie, less able to respond to chemical signalling with an electrical impulse, or action potential. It is hypothesized that this dulling of the responsiveness of the brain's reward pathways contributes to the inability to feel pleasure, known as anhedonia, often observed in addicts. The increased requirement for dopamine to maintain the same electrical activity is the basis of both physiological tolerance and withdrawal associated with addiction.

Downregulation can be classically conditioned. If a behavior consistently occurs in the same environment or contigently with a particular cue, the brain will adjust to the presence of the conditioned cues by decreasing the number of available receptors in the absence of the behavior. It is thought that many drug overdoses are not the result of a user taking a higher dose than is typical, but rather that the user is administering the same dose in a new environment.

In cases of physical dependency on depressants of the central nervous system such as opioids, barbiturates, or alcohol, the absence of the substance can lead to symptoms of severe physical discomfort. Withdrawal from alcohol or sedatives such as barbiturates or benzodiazepines (valium-family) can result in seizures and even death. By contrast, withdrawal from opioids, which can be extremely uncomfortable, is rarely if ever life-threatening. In cases of dependence and withdrawal, the body has become so dependent on high concentrations of the particular chemical that it has stopped producing its own natural versions (endogenous ligands) and instead produces opposing chemicals. When the addictive substance is withdrawn, the effects of the opposing chemicals can become overwhelming. For example, chronic use of sedatives (alcohol, barbiturates, or benzodiazepines) results in higher chronic levels of stimulating neurotransmitters such as glutamate. Very high levels of glutamate kill nerve cells (called excitatory neurotoxicity).

Criticism
Levi Bryant has criticized the term and concept of addiction as counterproductive in psychotherapy as it defines a patient's identity and makes it harder to become a non-addict. "The signifier 'addict' doesn't simply describe what I am, but initiates a way of relating to myself that informs how I relate to others."

A stronger form or criticism comes from Thomas Szasz, who denies that addiction is a psychiatric problem. In many of his works, he argues that addiction is a choice, and that a drug addict is one who simply prefers a socially taboo substance rather than, say, a low risk lifestyle. In 'Our Right to Drugs', Szasz cites the biography of Malcolm X to corroborate his economic views towards addiction: Malcolm claimed that quitting cigarettes was harder than shaking his heroine addiction. Szasz postulates that humans always have a choice, and it is foolish to call someone an 'addict' just becuase they prefer a drug induced euphoria to a more popular and socially welcome lifestyle.

A similar conclusion to that of Thomas Szasz may also be reached through very different reasoning. This is the somewhat extreme, yet tenable, view that humans do not have free will. From this perspective, being 'addicted' to a substance is no different than being 'addicted' to a job that you work everyday. Without the assumption of free will, every human action is the result of the naturally occuring reactions of particle matter in the physical brain, and so there is no longer room for the concept of 'addiction', since, in this view, choice is an illusion of the human experience.

Casual addiction
The word addiction is also sometimes used colloquially to refer to something a person has a passion for. Such "addicts" include:


 * Biblioholics
 * Chocoholics
 * Workaholics