All posts by Genevieve Miller

A Perspective on Craving

I found the article written by J. A. Brewer, “Craving to quit: Psychological models and neurobiological mechanisms of mindfulness training as treatments for addictions,” to contain a useful description of addiction and craving.

One of the contributing factors to addiction is the formation of associative memories between the addiction and positive and negative affective states.  A smoker remembers that smoking when stressed helps him to relax, and that when he doesn’t smoke he feels stressed, so he is likely to keep smoking.  This in turn forms an addictive loop in which the smoker becomes stuck.

Craving is the urge to act on the desire for the addiction.  When a smoker hasn’t smoked in a while, he will begin to actively seek out a cigarette and will not feel like himself until after he has smoked.  However, it is important to note that craving is not a response to the object of addiction; rather, it is a response to the affective tone that accompanies the perceptual representation of the sensory object.  Craving is not about the actual cigarettes, it is about the feelings that accompany the cigarettes.

Stick to the Familiar

I recently read “Self-regulatory deficits associated with unpracticed mindfulness strategies for coping with acute pain” by D. R. Evans.  While mindfulness meditation has been shown to decrease pain perception, it turns out that it can actually be harmful in the short run.  Using this strategy of self regulation is unfamiliar and strange to most people, and can deplete the will-power to resist temptation.  For this reason, I think a more familiar pain-coping strategy might be better suited to addicts who are already struggling with self-regulation.  This is why I am interested to find out if the addict’s addiction can become a mantra that will help addicts tolerate pain.

Don’t Give Opium to Addicts

While reading “Addiction and the Treatment of Pain” written by P. Ziegler, I realized one potential my experiment could have to help addicts.  Most pain medications are opiate based, and these medications, while useful, can trigger relapse or new addictions in addicts.  For this reason it is important to find alternatives to treat pain in addicts.  I hypothesize that addicts might be able to harness the focus they use on their addiction to become less sensitive to pain.

Focus, Focus, Focus

I recently read the article “NEUROPHYSIOLOGICAL, PSYCHOLOGICAL, SPORT AND HEALTH DIMENSIONS OF THREE MEDITATION TECHNIQUES” written by Richard M. Buscombe.

The main thing that I found useful from this article was the description of several types of meditation.  There was breath based meditation, concentrative meditation, and mindfulness meditation.  I was particularly interested in the concentrative meditation, which involves developing a focus using a mental device, such as a mantra, body sensation, breath, or specific image.  Specifically, I was intrigued by Transcendental Meditation, which utilizes a mantra, which is a word or saying that is repeated in a rhythmic cycle.  I hypothesize that there could be a similarity between this form of meditation and addiction seeking behavior.  Addicts focus on one thing, which is their addiction.  Is it possible that this focus is similar to the focus on a mantra in meditation?

Additionally, there were some data collection techniques that might be useful.  Infiniti Thought Technology was a biofeedback system that could be used to measure blood volume, respiration rate, different brain waves, and muscle relaxation/tension.  I also liked how phenomenological data was analyzed using summaries that the participants had written.  I can do something similar to get an understanding of the addicts background and the reasoning behind the craving.

Gambling is not just a game

While reading the article “Compulsive features in behavioral addictions: the case of pathological gambling” written by Nadyel-Guebaly, I had several ideas for my research proposal, the biggest of which was to include gamblers as well as alcoholics.

Even though gambling is a behavioral addiction and alcoholism is a substance use disorder, they have many similarities.  I think it would be interesting to compare a behavioral addiction to a biologically based addiction because they are both addictions, just with different bases.  However, it might be hard to isolate gamblers from alcoholics because gambling often occurs with alcoholism.

One of the primary features of substance dependence is that “use is continued despite knowledge of having a persistent or recurrent physical or psychological problem.” Addicts compulsively use drugs without any thought of the consequences.  This is similar to pathological gamblers, who can have a hard time quitting gambling despite negative consequences such as losing all of their money.  These compulsive behaviors are associated with obsessive thoughts over the behaviors.  Both of these addictions are ego-syntonic, meaning they feel pleasure, gratification, or relief when they commit the act.  They cannot stop their addiction, because when they are in withdrawal they feel stress and anxiety which they want to get rid of.  The easiest way to not feel withdrawal symptoms is to not be in withdrawal anymore by taking the addictive substance or doing the addictive behavior.  Gamblers feels craving and withdrawal just like alcoholics do.

There are, according to Koob and Volkow, three stages of the addiction cycle: binge/intoxication, withdrawal/negative effect, preoccupation/anticipation (craving).  There are specific brain regions associated with each of these stages.  Binge/intoxication is associated with the ventral tegmental and ventral striatum.  Withdrawal/negative affect is associated with the extended amygdala.  Preoccupation/anticipation is associated with the orbitofrontal cortexdorsal striatum, prefrontal cortex, basolater amygdala, hippocampus, and insula.  It is this stage that I am particularly interested in.  I hypothesize that the preoccupation and anticipation of the addiction might be similar to having a mantra in meditation, which is related to increased pain tolerance.

For even more biology, there are different neurotransmitter systems that contribute to substance addiction and gambling.  Serotonin contributes to behavioral inhibition, and when it is suppressed the addicts feel a euphoric high.  Dopamine is related to learning, motivation, and salience of stimuli, including pleasureful rewards for enacting the addictive behavior.  Even though gambling is a behavioral addition and alcoholism is a substance use addiction, both of them effect the brain is a similar manner.

Loving the Pain

The article “What Imaging Teaches Us About Pain” by Elizabeth Church was very informative to me.

First, it describes pain.  As much as we may hate pain and avoid it at all costs, pain is actually a good thing.  It is “an alarm system that protects individual organisms from potential or actual physical threats.”  It is a complex sensory and emotional experience that warns us if there is potential or actual damage to us, or if something is just wrong.  One type of pain described is nociception, which is the activation of nerve endings that respond differently to tissue-damaging stimuli.  The activation of these nerve endings may or may not be perceived as pain.  Pain is actually a very subjective experience.  Our experience of pain is completely dependent on our interpretation of it.  It is colored by our belief about the pain, our expectations, and our mood.  Our perceptions may or may not match with the nociceptive input.  Basically, our pain is fueled by our mind.

However, biology comes into play as well with genetic factors that influence the experience of pain.  There are even specific neurotransmitters in the forebrain that are involved with the reduction of the intensity of the pain experience.  The pain matrix is a large network that becomes activated during the nociceptive processing.  What is interesting is that individuals have different portions of the central nervous system that play different roles in pain processing in this pain network.  To get into some hard biology, there are common regions of the brain that are involved in pain processing.  These include the sensory-discriminatory areas of the central nervous system, which are the parietal lobe of the cerebral cortex, including the primary somatosensory (sense of touch), secondary somatosensory, thalamus (relays sensory information), and posterior portions of the insula (linked to regulation of emotion and homeostasis, perception, motor control, self awareness, and cognitive functioning).  Also, areas of the brain associated with cognition and affect (anterior portions of the insula, the anterior cingulated cortex, and the prefrontal cortex) help regulate pain.

As far as I can see, a lot of pain processing is located in the brain.  This means that neural imaging can be used to show pain intensity in an objective manner versus the normal participant evaluations that are subjective to their experiences.  While an fMRI would be nice to use to an imaging tool, it seems a little bulky for my experimental design, so I think DOT diffuse optical tomography might work better.  The participant wears a helmet with lights sources and detectors that absorb and respond to light, and by some scientific magic  this detects changes in cerebral blood flow, which show areas of brain activity.  I think that this method will be a nice addition to the subjective VAS scale I intend to include in my experimental design.

Another interesting point of this article was that the best alternative (non-medication) treatment of pain is meditation.  Meditation overall can improve attention, relieve anxiety and depression, reduce anger and cortisol levels, and strengthen immune responses and gray matter density.  While the benefits of meditation are numerous, I could never get past the boring part myself.  Also, meditators had a lower pain sensitivity than control subjects.  When faced with heat, it took higher temperatures before they felt any pain!  The strength of this pain regulation depends on the amount of meditation experience, and unfortunately 2000 plus hours are needed for significant control of pain.  Short term meditation does have some effect, though.  I would love to contrast a meditator with a drug addict, because in a way addicts adhere to their own inner mantra.

Bells and Drool: A Way to Classically Relieve Pain

I think that the article “Classical conditioning and pain: Conditioned analgesia and hyperalgesia” written by G.Miguez might be useful for my research proposal.

This article describes how reaction to pain can actually be conditioned, or trained.  It uses the theory of classical conditioning, which was first described by Pavlov in his famous dog and bell experiment.  An unconditioned stimulus, such as food, causes an unconditioned response, such as drooling in dogs.  If a conditioned stimulus, such as the ringing of a bell, is paired with an unconditioned stimulus, then eventually the conditioned stimulus on its own will cause a conditioned response.  In this case, the ringing of a bell will cause the dog to drool even though there is no biological reason for a dog to drool at the ringing of a bell.

This is important for the regulation of pain sensitivity.  In humans, several types of stressors (unconditioned stimulus) result in an increased tolerance to pain (unconditioned response).  These stressors include, well, stress.  One example is intense physical activity (think of marathon runners who continue to run and soldiers who do not realize that they are wounded).  In animals, even a novel situation can cause a reduction in pain levels.  In humans, other stressors that result in reduced pain are loud noises, thermal stimulation, footshocks, and solving mental arithmetic problems and challenging memory tests.  So math is good for something at least.

If an initially neutral stimulus is paired with one of these stressors, it could reduce pain by acting as a conditioned stimulus.  The conditioned stimulus can be something in the environment.  However, it is important to note that not all stressors make changes in pain sensitivity in the same direction.  Some will cause less pain to be felt, others more.

As a way to relieve stress and escape from the struggles of everyday life, it is very possible that the substances of addiction are conditioned stimulus that have analgesic (pain relieving) properties.  Withdrawal comes with very negative side effects and makes those trying to quit feel miserable.  If an alcoholic who is craving a drink gives in to the temptation, he will be blissfully relieved of his withdrawal symptoms, even if it is only for a short time.  Therefore, I think it is reasonable to hypothesize that the substance becomes associated with feeling good and pain-free, and becomes a conditioned stimulus.  Maybe even the thought of the conditioned stimulus might have analgesic properties.

A Cold, Painful Task

I recently read “Effect of Brief Mindfulness Intervention on Tolerance and Distress of Pain Induced by Cold-Pressor Task” written by Xinghua Liu.

This article tested short term mindfulness meditation against distraction intervention on pain tolerance and pain intensity.  The mindfulness intervention included increasing awareness to bodily sensations and objectively accepting these experiences.  Mindfulness is accepting the pain rather than avoiding or fighting it.  The distraction intervention, which in most studies is completing hard math problems, was imagining a happy scene.  A distraction from the pain can lessen it.  Surprisingly, there was no significant difference in pain tolerance and intensity between subjects who used the mindfulness method and those who used the distraction method.  I was worried that, because mindfulness is negatively correlated with cravings and addiction and it is positively correlated with increased pain tolerance, addicts, who are not naturally mindful, will have a decreased pain tolerance.  This article shows, however, that there are different ways to tolerate pain, distraction being just as effective as mindfulness.  Even if the guided imaginings of the addicts are nothing like the process of meditation, I am interested to see if the repeated thought process involving addictions is similar to the distraction technique.  It might be good to have a control group that uses the distraction technique in my project.

Additionally, I think I will use the Cold pressor test mentioned in this article to measure pain.  The equipment is two plastic containers.  One is filled with warm water that is 37 degrees Celsius and the other with cold water and ice that is kept around 2 degrees Celsius.  To prevent the participants’ hands from touching the ice directly, the ice is wrapped in plastic and tucked away in a bottom corner of the container.  First, the participants place one of their hands in the warm container for two minutes to establish a baseline temperature.  Next, the participants move that same hand to the container that is cold.  They simply keep their hand in the water until they cannot handle the pain anymore, in which case they remove their hand from the water.  To prevent any damage to the hand, the maximum time limit is 5 minutes, but the participants are not told this.  Immediately after the procedure, the participants rate their pain experience.  This seems like a simple and effective design, and an overall good way to test what I am trying to measure.

Craving a Fix

I recently read the article “Cognitive and affective mechanisms linking trait mindfulness to craving among individuals in addiction recovery”  by E.L. Garland that I think I can use in my research proposal.

The article is about how mindfulness is related to craving.  Craving is the subjective experience of physical data related to the withdrawal from the cue (alcohol, drugs, etc.).  More than just the physiological experiences, craving is the inner interpretation of those experiences.  It is the constant thought of the craved substance, the anticipation of how good it will feel when the addict finally gets the substance, and all of the thoughts and behaviors that drive individuals to acquire the substance no matter what the cost.  I want to utilize this behavior in addicts to see if they are so focused in their cravings that they ignore reality, in the form of ignoring pain.  I wonder if their need for a fix is so great that other perceptions do not even register in their minds.  I feel like this repetitive, central goal might be somewhat similar to meditation that involves repeating a mantra, so I will have to read more on meditation.  Meditation could be a good contrast against addictions, since it is viewed in a positive light rather than a negative one and has already been shown to increase pain tolerance.

In this study, craving was measured using the Penn Alcohol Craving Scale.  It measures the duration, frequency, and intensity of craving for alcohol on a 7 point scale  with questions such as “How often have you thought about drinking or how good a drink would make you feel.”  This is perfectly designed to test the craving levels of the alcoholics in my proposal.  Since the scale was modified in the article to also measure cravings for drugs, I think it would be reasonable for me to modify the scale to measure the cravings of pathological gamblers.  This way, I would be able to compare the levels of craving of the addicted participants to their performance in the pain test.

 

A Guided Path Through Pain

The most important piece of information I gleamed from HC Fox’s article “Frequency of recent cocaine and alcohol use affects drug craving and associated responses to stress and drug-related cues” was the use of guided imagery.  Guided imagery involves “re-living” a recent stressful or drug-related personal event through guided imagery and recall.  I feel like this would be a good way to have the addicts in my study focus on their addiction before the pain test.  Instead of just telling the addicts to think of their addiction, this method would be standardized and repeatable, meaning the participants would all be told to imagine the same scenario.  It might be how they felt when they last indulged in their addiction, or imagining a scenario where they can indulge in their addiction all they want with no consequences.  I want to try and mimic the obsession that comes with intense addiction, and focusing in this manner might work.

Also, I liked the statistic analyses that were performed.  A linear mixed effect model is good when there are repeated measurements from the same individual.  This could be good if I have the participants do the pain test with and without the independent variable.  A T-test was performed, which is good to determine demographic and baseline drug differences.  Both of these statistical models could be used in my study.