craving

What is craving – do neurobiological accounts explain relapse in recovering alcoholics? Pt 2

Posted on by alcoholicsguide

If you want to drink, you will. It you do not, and depending on your regulation of emotions and stress, you may still relapse, even if one never intended to drink again.

In our previous blog we looked at automatic physiological response to cues that alcoholics appear to experience. These habitual responses are well explained by reinforcement, conditioning or neurobiological models of addiction.

However, do these neurobiological models predict relapse in abstinent alcoholics and addicts? In other words, do recovering alcoholics act and react to cues and have the same attentional bias, i.e. are they lured siren-like to alcohol or drug cues like lemmings to a drink or a drug or are there more  cognitive-affective processes at work in the craving than these models suggest!?

Does the mind play a role in transmuting these physiological urges into “craving”.

When I have seen a new comer to recovery craving they do not seem to walk around like a robot, salivating and rubbing their sweaty hands together. I have seen that when I was in active drinking and was like that innumerable times myself while under the spell of this “fleshy hunger” called having a pathological urge for a drink.

I am not downplaying this urge state, it is quite horrendous, it is like craving a glass of water after days in the desert. It feels like your very life depends on it, in other words. It can be a life or death feeling.

 

PowerPoint Presentation

In recovery, this urge state becomes more complicated and various other brain regions may become involved in this “craving” and there may be a interplay between regions rather than regions simply acting in concert – we will explore this more in series 3 of this theme of “craving”.

For now we examine how well do neurobiological accounts (i.e. accounts which focus primarily on impairments in neurotransmitter and stress systems and brain function in areas which create a cascade of ‘knock on’ impairment and dysfunction in areas of the prefrontal cortex which deals with cognitive control of behaviour with resultant dysfunction in areas which deal with reward, motivation stress and emotional response and more motoric, habitualized action) predict behaviour in abstinent, treatment seeking individuals?

Here we simply consider how well aspects of these theories, such as the ideas relating to craving (urge) via cue reactivity (an attentional bias towards alcohol and drug associated cues in the environment)  and positive memory associations for previous alcohol or drug use, relate to, or are relevent to the experiential reality of everyday recovering alcoholics and addicts.

In simple terms, it is the duty of science to attempt to predict behaviour, so how well do these models, especially the positive reinforcement model, predict the behaviour of treatment seeking abstinent alcoholics and addicts. 

Factors in relapse

Cues, external especially, which is a central part of positive reinforcement models, seem to be only one of various factors in relapse. They are present in a relatively small minority of studies or interact with other variables such as stress and negative affect (NA). So how well does this then validate this theory of addiction, when it is only present in a minor way in relapse and usually alongside stress and NA. Does this mean it plays a role when interacting with these variables of stress/NA. Does it play a role on it’s own?

I forward this question because the looking at an alcohol cue by an alcoholic even in recovery/abstinence invokes stress reactions such as anxiety or negative emotions such as anger, sadness ( ). Can we say there is a non-stress influenced cue-reactivity? Is there a purely dopaminergic cue reactivity? It doesn’t appear so.

In fact moving on from noting this intrinsic stress response in cue reactivity, various studies show that the highest high-risk relapse situations are negative emotions, testing personal control, social pressure, and urge and temptations  (1), that 62 –73% of relapse episodes were due to negative emotion and social pressure. Heroin addicts relapse primarily because of NE and lack of social supports. Mood state, along with social isolation and family factors, was more likely to be related to relapse incidences with a positive correlation between NE and alcohol-seeking behaviour. Thus the most commonly cited reason for relapse was negative mood states, consistent with previous studies of relapse factors (2).  Also reasons for relapse did not differ in relation to the primary drug of dependence (alcohol, methamphetamine, heroin), reflecting the commonality of relapse processes across diverse types of substances.

Marlatt (3,4) , views relapse as an unfolding process in which resumption of substance use is the last event in a long sequence of maladaptive responses to internal or extemal stressors such as negative emotional states, interpersonal conflicts, and social pressures. In fact negative emotional states ….coping, self-efficacy and stressful life events appeared to be of greater import in determining relapse than ‘cues’.

It would appear that cue associated stimuli plays a minor role in relapse, with stress and NA appearing to be a more important determinant of relapse. So conditioning models do not appear to give a comprehensive account of relapse and this may be particularly the case in abstinent, treatment seeking alcoholics.

How does conditioning methodology adequately explain this group?

Attentional Bias

Do treatment seeking alcoholic have the same attentional bias as non treatment seeking active alcoholics?

In fact, studies seem to show a negative attentional bias in alcohol-dependent patients that may be interpreted as an avoidance of alcohol-related stimuli.

Townshend and Duka (2007) propose that treatment seeking individuals have established active avoiding strategies and  are able to disengage their attention from alcohol cues (5). In fact is suggested that a positive attentional bias towards alcohol cues occurs when stimuli were presented shortly (50 ms), followed by a disengagement from alcohol cues in the 500 ms interval of cue presentation. This corresponds with a cognitive model of craving of Tiffany (6) where the 50ms may represent automatic approach before this automatic bias is interfered with by cognitive control, perhaps resulting in ‘craving’.

Does this visual approach–disengagement pattern reflect an  attentional bias which is appetitive or threat based? If there is avoidance are cues similar as  seen as in those with trait anxiety who have attentional bias for threat-related cues (7). A large body of evidence indicates that aversive emotional states are associated with biases in cognitive processing and, specifically, with increased attentional processing of threat-related cues.Is this also how treatment seeking addicted individuals are responding to substance-related cues? It may that stress heightens the salience of attractiveness of the cues so that abstinent individual relapse because of stress based response which makes relapse via internal and external cues a solution to their chronic stress/emotional distress?

Or it may be that relapse is based on difficulties coping with the manifestation of chronic stress, emotional distress and that  relapse  is a more complicated process than simply being lured, siren-like, to relapse via cues.

In most of the relapses we have encountered it has been a ongoing build up to relapse. There has been a period of emotional dyregulation whereby individuals get more and more distressed, often in inter-personal relationships, and have a “to hell with it!” relapse to relieve escalating emotional distress and the distorted thinking that goes with it. It is not due to automatic or motoric proceses, it is mediated via affective-cognitive mechanisms and this is why the information processing model, with some modifications, appears to explain craving and relapse more satisfactorily.

If you want to drink, you will, it you do not, and depending on your regulation of emotions and stress, you may still relapse, even if one never intended to drink again, due to the torturous intrusive thoughts which accompany this cognitive and emotionally based “craving”, more akin to the “mental obsession ” of AA’s Big Book than purely physiological urges.

References

1. El, S., Salah El, G., & Bashir, T. Z. (2004). High-risk relapse situations and self-efficacy: Comparison between alcoholics and heroin addicts. Addictive behaviors, 29(4), 753-758.

2.  Hammerbacher, M., & Lyvers, M. (2006). Factors associated with relapse among clients in Australian substance disorder treatment facilities. Journal of substance use, 11(6), 387-394.

3. Marlatt, G.A. (1978) Craving for alcohol, loss of control and relapse: Cognitive behavioural analysis. In: Nathan, P.E., Marlatt, G.A., and Loberg, T. eds. Alcoholism: new directions in behavioural research and treatment. Plenum Press, New York, 271-314.

4. Marlatt, G.A., and Gordon, J.R. (1985). Relapse prevention: maintenance strategies in the treatment of addictive behaviors. Guilford  Press, New York.

5. Townshend JM, Duka T . Attentional bias associated with alcohol cues: differences between heavy and occasional social drinkers. Psychopharmacology (Berl)2001;157:67–74.

6. Tiffany, S. T. (1990). A cognitive model of drug urges and drug-use behavior: role of automatic and nonautomatic processes. Psychological review, 97(2), 147.

7.  Bar-Haim, Y., Lamy, D., Pergamin, L., Bakermans-Kranenburg, M. J., & van IJzendoorn, M. H. (2007). Threat-related attentional bias in anxious and nonanxious individuals: a meta-analytic study. Psychological bulletin, 133(1), 1.

8.  McCusker CG  Cognitive biases and addiction: an evolution in theory and method. Addiction 2001;96:47–56.

What is craving?

Posted on by alcoholicsguide

When I first came into recovery I used to get frightened by other abstinent  alcoholics proclaim that they were so glad they did not get the “wet tongue” when they saw alcohol or people drinking alcohol.  I used to feel ashamed as I did have an instantaneous “wet tongue” and still do  years later when I see people drinking alcohol. Is this a “craving” for alcohol, do I still want to drink? Do I still have an “alcoholic mind?“.

It used to churn me up, these so-called alcoholics who had no a  physiological response to alcohol-related “cues”.

What I have discovered is that I have an “alcoholic brain” and not a “alcoholic mind” and there is a huge difference. So if there are people out there relatively new to recovery, listen up. For chronic alcoholics there is an automatic physiological response when we see cues such as other people drinking. Automatic, habitual, it happens to us rather than us wanting or willing it to happen. It happens unconsciously without our say so!

Some researchers in science call this a craving. I disagree. I call this an physiological urge, distinct from craving. I think a craving is more akin to a “mental obsession” about alcohol.

It is hugely important for recovering persons that we distinguish between urges and craving, in a clear manner that science seems to have been unable to do! Lives can depend on this. We are so vulnerable in early recover that we need so sound direction on what is happening to us automatically and what we are encouraging to happen, consciously.

An urge for me is a physiological response to cues, external and internal (e.g. stress). A craving is different but interlinked.

If I have an urge and it becomes accompanied by automatic intrusive thoughts such as a drink would be nice, and maybe a suggestion on where to get this drink, this does not mean I want a drink. It is simply automatically prompted intrusive thoughts, the type of thought I used to get all the time and so became habitual, became stored away in an automatized addiction schema or addiction action plan.

If I realize this and simply  these thoughts go, i.e. do not react to them, then they lessen and dissipate altogether.

This is not a craving. I have not consciously and emotionally engaged with these intrusive thoughts.

So what I am saying is that there is no simple urge state that automatically leads to drink. We have to cognitively and emotionally react to it.

In my time in recovery, I have rarely heard of or witnessed  someone lured siren-like by a cue to a drink and when I have it is because he wanted to drink really, were testing their alcoholism, or that he was in huge emotional distress and went to “hell with it!”. As we will see below, stress and cues certainly do not mix but again there is still a cognitive-emotional reaction which mediates between an urge and a relapse!

In the first of a four part series of blogs we discuss “what is craving?” and consider whether the emotional dysregulation we consider to be at the heart of alcoholism and addiction also plays a role in both craving and relapse.

We start this series by considering the neurobiological accounts of craving and will then consider how well these accounts explain craving and relapse in abstinent, treatment seeking, or recovering alcoholics and addicts.

Part 1

What is craving?

Craving persists years into abstinence (1).

Precise definitions of craving have remained elusive (2-5). Two general categories are based on conditioning and cognitive mechanisms (6) but are not mutually exclusive.

A Neuroadaptive Model of Craving – Scientists believe that a gradual and, perhaps, permanent adaptation of brain function (i.e., neuroadaptation) to the presence of alcohol is a central feature in the development of alcohol dependence (7,8).

Conditioning Models – The “conditioning” models posit that cues elicit the same physiological and psychological response as drug consumption itself  with these ‘respondent’ conditioning theories predicting that responses to drug-related cues either reflect aversive abstinence symptoms or mimic drug effects  have dominated explanatory models in cue reactivity studies (9).

The definition of addiction by the American Society of Addiction Medicine (ASAM) includes the terms craving and persistent risk, and emphasises risk of relapse after periods of abstinence triggered by exposure to substance-related cues and emotional stressors (10).

This conceptualisation points to the role of substance-related cues, e.g., environmental stimuli that are strongly associated with the effects of the administration of substances and acquire incentive salience through Pavlovian conditioning, as well as stress (an internal cue), as major determinants of relapse.

The Incentive Sensitisation (IS) Model (11), addiction is the result of neural sensitisation of reward circuits (centred in the ventral striatum (VS)) by the neurotransmitter dopamine. Positive reinforcement mechanisms lead to a non-associative learning process, referred to as sensitization, in which repeated confrontation with a substance-related cue (which acts as a reinforcer) results in the progressive amplification of a response (substance seeking).

This ‘sensitisation’ or hypersensitivity may be independent of negative withdrawal symptoms or an individual’s general negative emotional state and leads to compulsive substance-seeking and substance-taking. These mechanisms of positive reinforcement leave addicts vulnerable to relapse when confronted with substance-related cues that trigger a pathological “wanting”. In short, IS produces a bias of attentional processing towards substance-associated stimuli and a pathological wanting of alcohol or substances. Sensitisation and attentional bias have been demonstrated in various studies (12,13).

Negative reinforcement model of addiction Basic negative reinforcement models pose that addictive behaviour is the consequence of persistent negative affect (NA). This NA is associated with maladaptive changes in the brain’s stress and reward circuits, which leave addicts vulnerable to cue-associated stimuli prompting a desire to relieve their negative emotional states (14).

One prominent stress-based negative reinforcement model, the Hedonic Dysregulation (HD) Model, mainly associated with Koob and le Moal (14), In sum, the HD model posits that, in substance dependent individuals,  an overactive stress  axis creates a progressive allostasis in the brain reward systems which underlies transition from substance use to addiction and creates a persistent state of NA (altered and excessive stress) and emotional reaction to “cues”. These changes continue to persist even when an addicted individual experiences a state of protracted abstinence.

Persistent NA increases their incentive salience and desire to use substances in an attempt to relieve this NA.

Evidence for the involvement of both the reward and the stress system of the brain  comes from imaging studies of addicted individuals during withdrawal or protracted abstinence, which have shown decreases in dopamine D2 receptor density (hypothesized to reflect hypodopaminergic function) (15) as well as alteration in brain stress systems, such as increase in CRF and glucocorticoids (16).

These models to me appear to be describing urges based on cues and the effect of cues with stress/emotional distress. This last one can impact on recovery and relapse mentioned in another blog.

The question remains however whether these neurobiological models predict relapse in abstinent alcoholics and addicts?

 

References 

1.  Anton, R. F. (1999). What is craving. Alcohol Research and Health, 23(3), 165-173.

2. LUDWIG, A.M., AND STARK, L.H. Alcohol craving: Subjective and situational aspects. Quarterly Journal of Studies on Alcohol 35:899–905, 1974.

3. KOZLOWSKI, L.T., AND WILKINSON, D.A. Use and misuse of the concept of craving by alcohol, tobacco, and drug researchers. British Journal of Medicine 82:31–45, 1987.

4.  KOZLOWSKI, L.T.; MANN, R.E.; WILKINSON, D.A.; AND POULOS, C.X. “Cravings” are ambiguous: Ask about urges and desires. Addictive Behaviors 14:443–445, 1989

5.  SITHARTHAN, T.; MCGRATH, D.; SITHARTHAN, G.; AND SAUNDERS, J.B. Meaning of craving in research on addiction. Psychological Reports 71:823–826, 1992.

6. SINGLETON, E.G., AND GORELICK, D.A. Mechanisms of alcohol craving and their clinical implications. In: Galanter, M., ed. Recent Developments in Alcoholism: Volume 14. The Consequences of Alcoholism. New
York: Plenum Press, 1998. pp. 177–195.

7. Robinson, T.E., & Berridge, K.C. (1993). The neural basis of drug craving: An incentive-sensitization theory of addiction. Brain Research, 18, 247-291

8. Koob GF, Le Moal M. Drug abuse: hedonic homeostatic dysregulation. Science. 1997;278:52–58

9.  Ingjaldsson, J. T., Laberg, J. C., & Thayer, J. F. (2003). Reduced heart rate variability in chronic alcohol abuse: relationship with negative mood, chronic thought suppression, and compulsive drinking. Biological Psychiatry, 54(12), 1427-1436.

10.  Morse RM, Flavin DK (1992). “The definition of alcoholism. The Joint Committee of the National Council on Alcoholism and Drug Dependence and the American Society of Addiction Medicine to Study the Definition and Criteria for the Diagnosis of Alcoholism“. JAMA 268 (8): 1012–4

11. Robinson, T. E., & Berridge, K. C. (2008). The incentive sensitization theory of addiction: some current issues. Philosophical Transactions of the Royal Society B: Biological Sciences, 363(1507), 3137-3146

12. Leyton M. Conditioned and sensitized responses to stimulant drugs in humans. Prog. Neuropsychopharmacol. Biol. Psychiatry. 2007;31:1601–1613.

13. Franken, I. H. (2003). Drug craving and addiction: integrating psychological and neuropsychopharmacological approaches. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 27(4), 563-579

14. Koob, G. F., & LeMoal, M. (2001). Drug addiction, dysregulation of reward, and allostasis. Neuropsychopharmacology, 24, 97–129.

15. Volkow ND, Wang GJ, Fowler JS, et al. Decreased striatal dopaminergic responsiveness in detoxified cocaine-dependent subjects. Nature. 1997;386:830–3.

16.. Koob GF, Le Moal M. Addiction and the brain antireward system. Annu Rev Psychol. 2008;59:29–53

An Emotional Disease?

Posted on by alcoholicsguide

Is Addiction an Emotional Disease!?

“Addiction”, is widely viewed as a chronic, relapsing, neurobiological disorder, characterized by compulsive use of alcohol or substances, despite serious negative consequences. It involves both physiological and psychological dependence and leads to the emergence of a negative emotional state.  The Diagnostic and Statistical Manual of Mental Disorders, DSM-5, combines DSM-IV categories of substance abuse and dependence into a single disorder, on a continuum from mild to severe.  The previous definition of addiction by the American Society of Addiction Medicine (ASAM) includes the terms, craving, persistent risk, and emphasizes risk of relapse after periods of abstinence triggered by exposure to substance-related cues and emotional stressors . This conceptualisation points to the role of substance-related cues, e.g., environmental stimuli that are strongly associated with the effects of the administration of substances and acquire incentive salience through Pavlovian conditioning, as well as stress (an internal cue), as major determinants of relapse.

For example in terms of the reasons for relapse implicated in much research, alcoholics relapse due to ‘cue-reactivity’ i.e. they see ‘people, places, or things’ associated with their drinking past and they are drawn to it and simply relapse.

 In some years of recovery, we have rarely heard of a committed abstinent alcoholic addict in recovery who relapsed simply because he/she was lured siren like to some cue associated stimuli. That is not to say cue reactivity is not a valid construct, it is obviously. Recovering alcoholics  exhibit an automatic, that is involuntary,  attentional bias towards drug and alcohol-related “cues”. This is a torturous aspect of early recovery thus most therapeutic regimes advise those in early abstinence and recovery to avoid “people, places and things” that act as  cue-associated stimuli. In fact, some in early recovery do challenge this only to learn painfully as the result by thinking they can spend time, like before, in drinking establishments,  only to find that it is “like sitting in a hairdressors  all day and not expecting to eventually get a haircut!”

A more recent  ASAM definition includes “Addiction is a primary, chronic disease of brain reward, motivation, memory and related circuitry. Dysfunction in these circuits leads to characteristic biological, psychological, social and spiritual manifestations. Addiction is characterized by inability to consistently abstain, impairment in behavioral control, craving, diminished recognition of significant problems with one’s behaviors and interpersonal relationships, and a dysfunctional emotional response.”

We appreciate the role now afforded to “dysfunctional emotional response” in this new definition as we believe it is dysfunctional emotional response which is at the heart of alcoholism and addiction.

Our own experience of recovery, coupled with our neuroscientific research over several years, has  made us curious as why the ways addicts and alcoholics talk about their condition or the explanations they forward all generally point to what they would call an “emotional disease” or “a parasite the feeds on their emotions”, an “emotional cancer” or a “fear based disease” yet these are rarely countenanced in any theory of addiction, whether neurobiological, psychological, psycho-analytical (although there have been very interesting ideas based on attachment within this methodology).

How could addicts and alcoholics be so wrong about themselves and what ails them? Especially when they see it also in hundreds of others with the same condition? We doubt that they are wrong, in fact, we have in recent years taken the opposite approach and started to explore, in terms of research, if addiction and alcoholism, especially, have their roots in emotional dysregulation and emotional processing deficits

In even more recent times, we have been encouraged that these difficulties also shape decision making difficulties, distress based impulsivity (leading to compulsivity) lack of inhibition across various psychological domains, as well as more revealingly the cognitive and executive dysfunctions and ‘flight or flight’ reactions which seem common to this group, over reacting in other words.

There appears to be a short term decision making profile which we suggest is distress based, which implicates more emotive-motoric “automatic,compulsive”regions of the brain rather than goal-directed. A more “let’s do it NOW!”way of making decisions.  This is also seen in children of alcoholics.

Could this be an important vulnerabilty to alcoholism? In order to get this debate going we will now consider whether there are possibilities for re-defining the DSM criterion in relation to the manifest difficulties observed in these clinical groups in relation to emotional dysregulation. The “official” nosology (e.g. DSM IV) is largely limited to physical manifestations of addiction although addicted individuals display additional psychiatric symptoms that affect their well-being and social functioning but which have been relegated to the domain of psychiatric “comorbidity.” 

Although the relationship of these psychiatric symptoms with addiction is very close, substance abuse may modify pre-existing psychic structures and lead to addiction as a specific mental disorder, inclusive of symptoms pertaining to mood/anxiety, or impulse control dimensions, decision making difficulties or, as we suggest, the various characteristics of emotional dysregulation. All of which suggests the current DSM based nosology of addiction-related mental comorbidity does not consider the overlap of the biological substrates and neurophysiology of addictive processes and psychiatric symptoms associated with addiction, so fails to include specific mood, anxiety, and impulse control dimensions and decision making difficulties in the psychopathology of addictive processes.

Addiction reaches beyond the mere result of drug-elicited effects on the brain and cannot be peremptorily equated only with the use of drugs despite the adverse consequences produced. Addiction is a relapsing chronic condition in which these psychiatric manifestations play a crucial role. Thus it may be that the aetiology of addiction cannot be severed from its psychopathological underpinning, it’s roots.  In may have been initiated by these mechanisms and also the addiction cycle may be continually perpetuated by them. Particularly in view of the undeniable presence of symptoms, of their manifest contribution to the way addicted patients feel and behave, and to the role they play in maintaining the continued use of substances.

In other words, the latter symptoms frequently precede the addictive process constituting a predisposing psychological background on which substance effects and addictive processes interact, leading to a full-fledged psychiatric disorder. Within the frame of the current DSM, numerous relevant psychiatric issues in substance abuse disorders may have been overlooked.   Even in the absence of psychiatric diagnosis, specific psychological vulnerabilities may constitute a background for the development of  disorders. The neural circuitry implicated in affective reactivity and regulation is closely related to the circuitry proposed to underlie addictive behaviours.  Affect is related to dysfunctional decision-making processes and risky behaviours,  In fact, we suggest these affective processing difficulties cause inherent decision making difficulties and constitute a premorbid vulnerability.

Substance dependence is associated with significant emotional dysregulation that influences cognition via numerous mechanisms. This dysregulation comes in the form of heightened reward sensitivity to drug-related stimuli, reduced sensitivity to natural reward stimuli, and heightened sensitivity of the brain’s stress systems that respond to threats. Such disturbances have the effect of biasing attentional processing toward drugs with powerful rewarding and/or anxiolytic effects. 

Emotional dysregulation can also result in impulsive actions and influence decision-making. It appears clear in addiction and alcoholism (substance dependence)  and that emotional processing significantly impairs cognition in substance dependence. Emotionally influenced cognitive impairments have serious negative effects with both the resultant attentional bias and decision-making deficits being predictive of drug relapse. 

The influence of emotion is clearly detrimental in substance dependence, and many of the detrimental effects observed are due to the ability of drugs of abuse to mimic the effects of stimuli or events that have survival significance. Drugs of abuse effectively trick the brain’s emotional systems into thinking that they have survival significance!

They trick the alcoholic into thinking he needs to drink to survive! 

It is important to note that the neural mechanisms implicated in neurobiological accounts of the transition to endpoint addiction from initial use are also experienced emotionally in human beings, in addicted individuals. That human beings, addicted individuals have to live with these profound alterations and impairments of various regions and neural networks in the brain. And that it is in treating these human manifestation of this neurobiological disease, i.e. one’s “dysfunctional emotional responses” in every day life that is required for long term recovery. We have to manage the emotional difficulties which perpetuate this disease, this “parasite on our emotions”, otherwise these dysfunctional overwhelming emotions manage us.   

It is through this emotional dysregulation that the addiction cycle is experienced and via emotional means perpetuated! It is through living “emotionally light” and spiritually aware lives which help manage our emotions that perpetuate our long term recovery.

Emotional distress is at the heart of addiction and alcoholism, and relief from it on a continually, daily basis is at the heart of recovery.    

References

American Psychiatric Association (2013). Diagnostic and Statistical Manual of Mental Disorders (Fifth ed.). Arlington, VA: American Psychiatric Publishing. pp. 5–25.

Pani, Pier Paolo, et al. “Delineating the psychic structure of substance abuse and addictions: Should anxiety, mood and impulse-control dysregulation be included?.” Journal of affective disorders 122.3 (2010): 185-197.

Murphy, A., Taylor, E., & Elliott, R. (2012). The detrimental effects of emotional process dysregulation on decision-making in substance dependence. Frontiers in integrative neuroscience, 6.

Cheetham, A., Allen, N. B., Yücel, M., & Lubman, D. I. (2010). The role of affective dysregulation. in drug addiction. Clinical Psychology Review, 30(6), 621-634.