Explaining the negative consequences of Negative Urgency.
In various blogs we have suggested that one of the main aspects of addictive behaviours is to act as the result of distress-based impulsivity or negative urgency. Here we explore in more details what we mean by that term negative urgency. Here we borrow from one article (1) which has an excellent review of negative urgency (1). The experience of emotion facilitates action. It has long been recognized that emotional processing appears to prepare the body for action (Frijda, 1986; Lang, 1993; Saami, Mumme, & Campos, 1998). In fact, to emote means, literally, to prepare for action (Maxwell & Davidson, 2007). Researchers have theorized that the relationship between emotional experiences and actions involve activation of the motor cortex by limbic structures (Morgenson, Jones, & Yim, 1980). Some investigations have used neuroimaging techniques to document increased activity in motor areas of the brain during emotional processing (Bremner et al., 1999; Rauch et al., 1996), and nonhuman studies suggest the emotion-action interface may involve connections between the amygdala and the anterior cingulate cortex (ACC: Devinsky, Morrel, & Vogt, 1995). Hajcak et al. (2007) found that emotionally arousing stimuli increase motor cortex excitability. The authors theorized that there may be individual difference in emotional reactivity that may relate to differences in the amount of activation of the motor cortex areas. One takes action to meet the need identified by the emotion.Pinker (1997) makes this point by noting that “Most artificial intelligence researchers believe that freely behaving robots . . . will have to be programmed with something like emotions merely for them to know at every moment what to do next” (p. 374). Intense emotions can undermine rational, advantageous decision making (Bechara, 2004, 2005;Dolan, 2007; Driesbach, 2006; Shiv et al., 2005). It also appears to be true that attempts to regulate negative emotions can impair one’s ability to continue self-control behaviors (Muraven & Baumeister, 2000; Tice & Bratslavsky, 2000; Tice,Bratslavsky, & Baumeister, 2001). Thus, it is not surprising that individuals engage in other strategies to manage intense emotions that are ill-considered and maladaptive, in that they work against one’s long-term interests. For example, heavy alcohol use may be used to manage emotion. Daily diary studies of alcohol use indicate that individuals drink more on days when they experience anxiety and stress (Swendson et al., 2000). Indeed, negative affect states have been shown to correlate with a greater frequency of many maladaptive, addictive behaviors, including alcohol and drug abuse (Colder & Chassin, 1997;Cooper, 1994; Cooper et al., 2000; Martin & Sher, 1994;Peveler & Fairburn, 1990). This pattern also is true of bulimic behaviors; individuals tend to participate in more binge eating and purging behaviors on days during which they experienced negative emotions (Agras & Telch, 1998; Smyth et al., 2007). Emotions such as shame, guilt, anger, depression, loneliness, stress, anxiety, boredom, and rejection are often cited as triggers for binge and purge episodes (Jeppson, Richards, Hardman, & Granley, 2003). For bulimic women, engaging in binge eating produces a decline in the earlier negative emotion (Smyth et al., 2007). Because actions like these do appear to reduce negative affect, they are reinforced. Brain Pathways Related to Emotion-Based Action Brain system involved in emotion and action -the amygdala, the orbitofrontal cortex (OFC) and its medial sector (the ventromedial prefrontal cortex, or VM PFC:Bechara, 2005), and other areas of the prefrontal cortex (PFC:Barbas, 2007). The amygdala appears to be heavily involved in the experience of negative affect; more broadly, it is thought to play a role in directing attention to emotionally salient stimuli, particularly stressful or disturbing stimuli (Davidson, 2003). The OFC appears to be involved in the modulation of emotion-based reactivity (Davidson, 2003). OFC activity overrides emotional responses, apparently by providing information and a bias toward long-term, goal-directed behavior (Lewis & Todd, 2007). Davidson and his colleagues (Davidson, 1998, 2000,2003;Davidson & Irwin, 1999; Davidson, Putnam, & Larson, 2000) suggest the experience of intense emotion, and its accompanying potential actions, is inconsistent with one’s long-term goals. The OFC, perhaps particularly the left VM PFC, provides a biasing signal to avoid immediate reward, and thus maintain one’s pursuit of one’s longer-term goals. Davidson (2003) refers to this process as affect-guided planning and anticipation: with healthy left VMPFC functioning, one gains access to the emotion associated with anticipated outcomes consistent with one’s long-term goals. The ability to do so is, Davidson argues, the hallmark of adaptive, emotion-based decision making. At times, long-term affect-guided planning is difficult: the experience of intense emotions unrelated to one’s long-term interests may disrupt processing with regard to those interests (Gray, 1999; Preston, Buchanan, Stansfield, & Bechara, 2007). But healthy functioning of the left VM PFC helps one maintain an affective connection to one’s longer-term goals, and thus plan accordingly. Damage to the OFC, and perhaps damage specifically to the VM PFC, results in affective lability and rash action particularly in inhibiting the action of amygdaloid reactivity.
————————————————- The authors of this study put forward various reasons why OFC and VM PFC damage can cause rash action – we consider these before forwarding our own ideas of why OFC/ VM PFC damage may prompt distress based impulsivity. The OFC, perhaps particularly the left VM PFC, provides a biasing signal to avoid immediate reward, and thus maintain one’s pursuit of one’s longer-term goals. Davidson (2003) refers to this process as affect-guided planning and anticipation: with healthy left VM PFC functioning, one gains access to the emotion associated with anticipated outcomes consistent with one’s long-term goals. Activation of the left VM PFC also appears to inhibit amygdalar activity (Davidson, 1998), thus shortening the time course of the experience of negative affect and attention to stressful stimuli. Because negative affect stimulates autonomic nervous system (ANS) activity, which provides support for action in response to distress, prolonged negative affect leads to prolonged ANS arousal (Davidson, 2000). Perhaps a greater duration of ANS arousal increases the likelihood of affect-triggered action. Activity in the amygdala appears to facilitate this process. Damage to the OFC, and perhaps damage specifically to the VM PFC, results in affective lability and rash action. Individuals with PFC damage, and with OFC damage in particular, do not; they do not appear to have the normal anticipatory affective response to potential punishment (Bechara, 2004; Bechara, Tranel, Damasio, & Damasio, 1996; Cardinal et al., 2002). Thus, OFC damage appears to impair affective anticipation of potential risk to one’s actions. Bechara, Damasio, Damasio, and Anderson (1994) described OFC-damaged individuals as oblivious to the future consequences of their actions, but sensitive to immediate reinforcement and punishment. Thus, their actions tend to be guided by immediate consequences only. These patients had otherwise retained their intellectual capacities, including abstract reasoning skills. They could even describe possible future consequences in realistic language. They appeared simply to lack the anticipatory affect that others have; thus perhaps lacking the affect-guided anticipation described byDavidson (2003). The authors then suggest that associations between the OFC/VM PFC-amygdala system and psychopathy are consistent with their claim of an association between this system and the urgency traits. In other words, individuals high in psychopathy have reduced VM PFC functioning, and hence lack an affective connection to the consequences of their actions. Other studies have also documented similar OFC functioning deficits among psychopaths (Blair et al., 2006; Mitchell, Colledge, Leonard, & Blair, 2002). This model is interesting but there is not mention of stress systems in this model although the authors mention distress and negative affect but not the stress chemicals underpinning these affective manifestations. The authors also do no mention two hugely important points we believe; a. that this amgydaloid (hyper) activity, caused by PFC dysfunction can also “offline” PFC activity (fig.1) b. in favour of the compulsive, emotive-motoric behaviour of the dorsal striatum which drives rash action, distress-based impulsivity or compulsivity rendering the individual remote to negative consequence of actions, although he/she may be able to explain clearly these consequences. prior to or after seeming to not consider them. It is chronic stress dysregulation in addiction that “cuts off” access to action-outcome or goal-directed parts of the brain and recruits stimulus response, implicit, “must do” action instead. fig 1. This we believe is the mechanism of negative urgency rather than as the authors suggest in this article, but not included, that VMPFC damage renders individuals unknowing of consequence, when rather, consequence, negative or otherwise, has been cut off by this amygdaolid activity rendering action outcome associations remote to consciousness. The brain acts implicitly, procedurally or in a stimulus response way to distress we believe in addictive disorders when heightened amgydaloid reactivity is in charge of behaviour with VMPFC deficit contributing to this amgydaloid dysfunction. An argument against simply seeing rash behaviour as the result of OFC or VMPFC damage which leads to lack of knowledge of consequence is that it does not really consider the chronic stress that accompanies addictive behaviours and which creates a near constant distress which acts in the way we describe above. This does not mean that there is a lack of emotionally guided behaviour or action on the part of addicts. It would appear, as discussed in previous blogs, that emotional processing deficits are common in addiction and may not recruit the goal-directed parts of the brain as the authors suggest. They do not guided action or choices effectively. As a result they manifest in perhaps crude, undifferentiated or processed forms as distress signals instead and recruit more limbic, motoric regions of the brain. Hence they are not use to anticipate future, long term consequence. We are simply adding that as addiction becomes more chronic, so does stress and emotional distress and this appears to lead to a distress-based “fight or flight” responding to decision making that the authors have mentioned in this article but not elucidated as above. Addicts increasing appear to recruit sub-cortical or limbic areas in decision making and this is prevalent in abstinence as in active using. it is the consequence of chronic and stress dysregulation. We suggest that this chronic stress prompts negative urgency via an hypofunctioning ACC (2) and by a “emotional arousal habit bias” as seen in post traumatic stress disorder (3) whereby chronic emotional distress increasingly during the addiction cycle comes to implicitly activate dorsal striatal responding “offlining” the PFC in a similar manner to fig. 1. References 1. Cyders, M. A., & Smith, G. T. (2008). Emotion-based dispositions to rash action: positive and negative urgency. Psychological bulletin, 134(6), 807. 2. Li, C. S. R., & Sinha, R. (2008). Inhibitory control and emotional stress regulation: neuroimaging evidence for frontal–limbic dysfunction in psycho-stimulant addiction. Neuroscience & Biobehavioral Reviews,32(3), 581-597. 3. Goodman, J., Leong, K. C., & Packard, M. G. (2012). Emotional modulation of multiple memory systems: implications for the neurobiology of post-traumatic stress disorder.
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